What Impact Have State-Level Laws Had on Marijuana Use?

MedicalResearch.com Interview with:

MedicalResearch.com Interview with: Christine Mauro PhD Assistant Professor Biostatistics Columbia University Medical Center   MedicalResearch.com: What is the background for this study? What are the main findings?  Response:  As of November 2016, 28 states have legalized medical marijuana. Several previous studies have found an increase in use for adults after legalization, but not for adolescents.  We wanted to examine whether these age-specific findings varied by gender.  Consistent with past findings, we found past-month marijuana use did not increase after enactment of medical marijuana laws in men or women ages 12-25. Among people 26+, past-month marijuana use increased for men from 7.0% before to 8.7% after enactment (+1.7%, p<0.001) and for women from 3.1% before to 4.3% after enactment (+1.1%, p=0.013). Daily marijuana use also increased after enactment in this age group for both genders (men: 16.3% to 19.1%, +2.8 %, p=0.014; women: 9.2% to 12.7%, +3.4%, p=0.003). There were no statistically significant increases in past-year Marijuana Use Disorder prevalence for any age or gender group after medical marijuana law enactment.    MedicalResearch.com: What should clinicians and patients take away from your report? Response:  The readers should take away several things.  First, despite men being more likely to use marijuana than women are in all age groups, there were relatively few gender differences in terms of the impact of medical marijuana on marijuana use. Second, we found no evidence of an effect of medical marijuana law enactment in any marijuana use outcome for both men and women aged 12-17.  Lastly, we did see an increase in both past-month use and daily use among past-year users in both men and women aged 26+ after enactment, but no changes in past year marijuana used disorder.    MedicalResearch.com: What recommendations do you have for future research as a result of this study?  Response: Because most states in our sample more recently passed medical marijuana laws, it is possible that not enough time has elapsed to observe meaningful and significant changes in Marijuana Use Disorder. Given the impact Marijuana Use Disorder may have on individuals, families, and society, the prevalence of Marijuana Use Disorder should continue to be monitored regularly.   Second, there is considerable variation across provisions included in different states’ medical marijuana laws; some aspects, such as allowances on home cultivation or dispensaries, might have a role in changes in several health outcome indicators.  In addition, eight states have now legalized recreational marijuana, which may also have an impact on marijuana use outcomes over time. Future analyses should account for this variability in marijuana related policies.   MedicalResearch.com: Is there anything else you would like to add? Response: As marijuana use becomes more prevalent, monitoring state-wide trends in marijuana use by age and gender is important for public health planning. In particular, efforts to prevent and limit injury that may be associated with specific activities, such as driving, may be needed as daily marijuana use increases among adults. Downstream effects, either positive or negative, of a growing proportion of the adult population reporting daily marijuana use in states with medical marijuana laws warrants further attention. Disclosure: This work was supported by the National Institutes of Health, National Institute on Drug Abuse (grant R01 DA037866 to S. S. Martins).   MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.  Citation: Christine M. Mauro, Paul Newswanger, Julian Santaella-Tenorio, Pia M. Mauro, Hannah Carliner, Silvia S. Martins. Impact of Medical Marijuana Laws on State-Level Marijuana Use by Age and Gender, 2004–2013. Prevention Science, 2017; DOI: 10.1007/s11121-017-0848-3   Note:  Content is Not intended as medical advice.  Please consult your health care provider regarding your specific medical condition and questions.

Dr. Mauro

Christine Mauro PhD
Assistant Professor Biostatistics
Columbia University Medical Center 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: As of November 2016, 28 states have legalized medical marijuana. Several previous studies have found an increase in use for adults after legalization, but not for adolescents.

We wanted to examine whether these age-specific findings varied by gender.  Consistent with past findings, we found past-month marijuana use did not increase after enactment of medical marijuana laws in men or women ages 12-25. Among people 26+, past-month marijuana use increased for men from 7.0% before to 8.7% after enactment (+1.7%, p<0.001) and for women from 3.1% before to 4.3% after enactment (+1.1%, p=0.013). Daily marijuana use also increased after enactment in this age group for both genders (men: 16.3% to 19.1%, +2.8 %, p=0.014; women: 9.2% to 12.7%, +3.4%, p=0.003).

There were no statistically significant increases in past-year Marijuana Use Disorder prevalence for any age or gender group after medical marijuana law enactment.

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Labels of Majority of Online Cannabidiol Extracts Contain Inaccuracies

MedicalResearch.com Interview with:

Dr. Italia V. Rolle, PhD and Dr. Tim McAfee, MD Office on Smoking and Health National Center for Chronic Disease Prevention and Health Promotion CDC

Marijuana plant (Cannabis sativa)

Marcel Bonn-Miller, PhD
Adjunct assistant professor
Department of Psychiatry
Leader of the Substance Abuse and Anxiety Program
U.S. Veterans Affairs Department 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: A 2015 study found that edible cannabis products (e.g., brownies, cookies, drinks) are often mislabeled.  The FDA has also sent warning letters to a handful of companies selling cannabidiol extracts because of inaccurate labeling of content. This led us to conduct a systematic evaluation of the label accuracy of all cannabidiol extracts sold online.  We tested 84 products from 31 different companies.

The primary take-home of this study is that nearly 70 percent of all cannabidiol extracts sold online had over 10% more or less cannabidiol than advertised; 26% of products were over-labeled (less cannabidiol than indicated) and 42% of products were under-labeled (more cannabidiol than indicated).

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Marijuana Use Linked To Cognitive Impairment In HIV Patients

MedicalResearch.com Interview with:

Richard Saitz, MD, MPH, FACP, DFASAM Department of Community Health Sciences Boston University School of Public Health Clinical Addiction Research and Education (CARE) Unit Section of General Internal Medicine, Department of Medicin Boston University School of Medicine and Boston Medical Center Boston , Massachusetts

Dr. Saitz

Richard Saitz, MD, MPH, FACP, DFASAM
Department of Community Health Sciences
Boston University School of Public Health
Clinical Addiction Research and Education (CARE) Unit
Section of General Internal Medicine, Department of Medicin
Boston University School of Medicine and Boston Medical Center
Boston , Massachusetts

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Many people living with HIV infection use alcohol and other drugs including marijuana. People with HIV infection are also susceptible to cognitive dysfunction from many causes from HIV infection itself to aging.

The main findings were that among people with HIV and substance use disorder, lifetime marijuana and alcohol use were not associated with cognitive dysfunction, likely due to competing risks.  But current marijuana use was associated with cognitive dysfunction.

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Edible Marijuana Preferred By Consumers Due To Lack of Smoke and Convenience

MedicalResearch.com Interview with:

Sheryl Cates RTI International

Sheryl Cates

Sheryl Cates
RTI International
Durham, NC

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The goal of this research was to provide a better understanding of consumer perceptions of edible marijuana products, including why users prefer edibles relative to other forms of marijuana such as smoking and vaping and concerns regarding the consumption of edibles. This is important as more states legalize the use of recreational marijuana products. With the increasing popularity of edibles, concerns exist that do not exist with other methods of using marijuana, such as smoking or vaping. These concerns include delayed activation time; accidental ingestion, particularly by children and older adults; and dose titration.

The study team conducted eight focus groups (four groups in Denver, Colorado, and four groups in Seattle, Washington) with users of edibles. Most participants preferred edibles to smoking marijuana because there is no smell from smoke and no secondhand smoke. Other reasons participants like edibles included convenience, discreetness, longer-lasting highs, less intense highs, and edibles’ ability to aid in relaxation, reduce anxiety, and alleviate pain more so than smoking marijuana. Concerns and dislikes about edibles included delayed effects, unexpected highs, the unpredictability of the high, and inconsistency of distribution of marijuana in the product. No participants in either location mentioned harmful health effects from consuming edibles as a concern.  Although focus group findings are not generalizable, the findings are useful for helping inform policy makers and regulators as they establish regulations regarding the manufacture, labeling, and sale of edibles.

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Vaporizing Cannabis May Lead To Release Of Benzene Carcinogens

MedicalResearch.com Interview with:

Dr. Italia V. Rolle, PhD and Dr. Tim McAfee, MD Office on Smoking and Health National Center for Chronic Disease Prevention and Health Promotion CDC

Marijuana plant (Cannabis sativa)

Jiries Meehan-Atrash
Department of Chemistry, Portland State University
Portland, Oregon 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The need for this study stems from the rising popularity of cannabis, and specifically the fact that many consumers are under the belief that vaporizing extracts thereof is safer than smoking. While this may in fact have some truth to it, it is clear that we must assess the safety of vaporization a route of administration.

The main findings are that vaporizing terpenes under dabbing conditions generates some levels of methacrolein (a noxious irritant) at all temperatures that are hot enough to vaporize cannabinoids, but significant levels arise at higher temperatures that are more commonly used.

At the highest temperature used by consumers, significant levels of benzene arise, a compound that is a potent carcinogen and should be avoided at all costs.

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Washington-Oregon Study Shows Frequent Inter-State Diversion of Recreational Marijuana

MedicalResearch.com Interview with:
Benjamin Hansen, Keaton Miller, Caroline Weber

A dried Cannabis bud, typical of what is sold for drug use- Wikipedia image

A dried Cannabis bud, typical of what is sold for drug use- Wikipedia image

Department of Economics
University of Oregon

MedicalResearch.com: What is the background for this study?

Response: Recreational marijuana is now, or will soon be, legally available to 21%
of the United States population. A major concern among policy makers at
all levels of government is the trafficking or “diversion” of marijuana
from states where it is legal to other states. Though significant
measures are in place to prevent large scale drug trafficking by
licensed producers, consumers may easily purchase in one state and
travel to a different state for consumption or re-sale. Though this
policy concern has existed since medical marijuana became available in
the 1990s, the extent of this diversion by consumers has been unknown.

We take advantage of a unique natural experiment in the Pacific
Northwest: Oregon opened a recreational market on October 1, 2015, well
after Washington’s market opened on July 8, 2014. By examining the sales
of Washington retailers along the Washington-Oregon border in the months
before and after Oregon’s market opened, we can measure the extent to
which consumers from Oregon crossed state lines to purchase marijuana in
Washington.

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Heavy Marijuana Use May Harm Kidneys, But More Study Needed

MedicalResearch.com Interview with:

Dr. Julie H. Ishida MD Division of Nephrology, Department of Medicine San Francisco and San Francisco Veterans Affairs Medical Center University of California

Dr. Ishida

Dr. Julie H. Ishida MD
Division of Nephrology, Department of Medicine
San Francisco and San Francisco Veterans Affairs Medical Center
University of California

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Marijuana is becoming increasingly accepted in the United States, and animal studies suggest that marijuana could affect kidney function. However, data in humans are limited to case reports of acute kidney injury related to synthetic cannabinoid use and small cohort studies of relatively short duration.

Among 3,765 participants with normal kidney function in the Coronary Artery Risk Development in Young Adults or CARDIA study, my colleagues and I found that higher marijuana use was associated with lower kidney function at the start of the our study. However, we did not find that marijuana was associated with change in kidney function or albuminuria, which is a sign of kidney damage, over long-term follow-up.

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Chronic Cannabis Users Have Blunted Response To Stress

MedicalResearch.com Interview with:

Carrie Cuttler, Ph.D. Clinical Assistant Professor Washington State University Department of Psychology Pullman, WA, 99164-4820

Dr. Cuttler

Carrie Cuttler, Ph.D.
Clinical Assistant Professor
Washington State University
Department of Psychology
Pullman, WA, 99164-4820

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: One of the most common reasons cannabis users report using cannabis is to cope with stress. In support of this, previous research has shown that acute administration of THC or cannabis dampens affective responses and subjective stress ratings. However, our study is the first to compare the stress response of sober cannabis users to non-users. More specifically, we randomly assigned 42 non-cannabis users and 40 cannabis users (who abstained from using cannabis for at least 12 hours prior to the study) to either a stress or no stress condition. Participants in the stress condition were required to perform multiple trials of placing their hand in ice water and counting backwards from 2043 by 17s. Each time they made an error they were given negative feedback and told to start again. Further, they were being video recorded and their image was displayed in front of them. Participants who were assigned to the no stress condition were simply required to perform multiple trials of placing their hand in lukewarm water and counting from 1 to 25. They were not given feedback or recorded. Participants were asked to rate their level of stress and to provide a saliva sample, from which the stress hormone cortisol was measured.

The results showed that, as expected, non-users in the stress condition had higher cortisol levels and higher self-reported stress than non-users in the no stress condition. In contrast, cannabis users in the stress condition demonstrated the same levels of cortisol as cannabis users in the no stress condition and their increase in self-reported stress was smaller than that of the non-users.

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College Binge Drinkers Also Smoking More Pot In States Where Marijuana Legal

MedicalResearch.com Interview with:

David Kerr PhD Associate professor in the School of Psychological Science College of Liberal Arts Ohio State University 

Dr. Kerr

David Kerr PhD
Associate professor in the School of Psychological Science
College of Liberal Arts
Ohio State University 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Oregon legalized sale and use of marijuana for recreational purposes and the part of the law (regarding use) took effect in July 2015. However, there have been no controlled studies of which we’re aware of the possible effects of the Oregon law that take into account the trends toward increased marijuana use across the country and differences in use rates between states that predated the law.

We used survey data on college students in Oregon and in 6 states without recreational legalization to examine the issue.

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Pot Plus Alcohol Raises Fatal Traffic Accident Risk Over 500%

MedicalResearch.com Interview with:

Guohua Li DrPH, MD Professor and Director Center for Injury Epidemiology and Prevention Department of Epidemiology Mailman School of Public Health Columbia University

Dr. Li

Guohua Li DrPH, MD
Professor and Director
Center for Injury Epidemiology and Prevention
Department of Epidemiology
Mailman School of Public Health
Columbia University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Drugged driving has become a serious problem in the United States in the recent years due to increased consumption of marijuana and opioids. About 20% of fatally injured drivers used two or more substances, with alcohol-marijuana being the most commonly detected polydrug combination.

Our study of over 14000 fatal 2-car crashes indicates that drivers testing positive for alcohol, marijuana, or both are significantly more likely to be responsible for initiating these crashes than those using neither of the substances. Specifically, compared to drivers not using alcohol and marijuana, the risk of being responsible for initiating fatal crashes increases 62% for those testing positive for marijuana and negative for alcohol, 437% for those testing positive for alcohol and negative for marijuana, and 539% for those testing positive for both alcohol and marijuana. These results suggest that when used in combination, alcohol and marijuana have a positive interaction on the risk of fatal crash initiation.

The most common driver error leading to fatal 2-car crashes is failure to keep in proper lane, followed by failure to yield right of way and speeding.

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Roadside Oral Fluid Testing for Marijuana Intoxication

MedicalResearch.com Interview with:

Mitchell L. Doucette, MS PhD Candidate The William Haddon Jr Fellowship in Injury Prevention 2017 Co-Fellow Center for Injury Research and Policy Department of Health Management and Policy Johns Hopkins Bloomberg School of Public Health Baltimore, MD 21205

Mitchell Doucette

Mitchell L. Doucette, MS
PhD Candidate
The William Haddon Jr Fellowship in Injury Prevention 2017 Co-Fellow
Center for Injury Research and Policy
Department of Health Management and Policy
Johns Hopkins Bloomberg School of Public Health
Baltimore, MD 21205

MedicalResearch.com: What is the background for this study?

Response: Currently in the U.S., 8 states have legalized marijuana for recreational use and an additional 28 states permit marijuana for medical use. Some states have instituted a legal driving limit for marijuana intoxication, 5 ng/mL, and for Colorado specifically, research indicates the average time from law enforcement dispatch to blood sample collection was 2.32 hours—a period of time outside the window of legal sample collection under state law and peak THC detectability. Countries with similar marijuana driving limits perform roadside oral fluid testing for establishing intoxication at point of arrest.

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New Marijuana Laws Associated With Increase in Cannabis-Related Health Problems

MedicalResearch.com Interview with:

Deborah S. Hasin, Ph.D. Professor of Epidemiology Columbia University New York, New York 10032

Dr. Hasin

Deborah S. Hasin, Ph.D.
Professor of Epidemiology
Columbia University
New York, New York 10032

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Among adults, the prevalence of cannabis use and cannabis use disorders has increased in recent years. Concerns have been raised that for various reasons, medical marijuana laws would promote use of cannabis and consequently, cannabis-related consequences.

Many studies show that this didn’t happen among adolescents, but very little was known about the relationship between medical marijuana laws and adults. Using data from three surveys spanning the years 1991-2013, the study findings suggested that medical marijuana laws did play a role in increasing rates of cannabis use and cannabis use disorders.

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Cannabis Exacerbates Schizophrenia Symptoms and Prolongs Recovery

MedicalResearch.com Interview with:
Ian Hamilton

Department of Health Sciences
University of York
York, UK 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: This review looked back over 40 years of research on the links between cannabis and psychosis to examine how knowledge has developed on this issue.

The review found that there is sufficient evidence to suggest a dose response relationship exists in the risk for developing a psychosis that would not have happened if the individual had not been exposed to cannabis. Also for people with schizophrenia cannabis exacerbates their symptoms and prolongs recovery.

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Regular Marijuana Use is Costly Healthwise, Especially When Started As Teenager

MedicalResearch.com Interview with:

James McIntosh PhD Economics Department Concordia University Montreal, Quebec, Canada.

Dr. McIntosh

James McIntosh PhD
Economics Department
Concordia University
Montreal, Quebec, Canada.

MedicalResearch.com: What is the background for this study

Response: Marijuana is about to become legal in Canada. Consequently, an analysis of its effects on users is a high priority. This issue has been explored by Canadian researchers to some extent but there are gaps in what is known about the effects of using marijuana. Most of the Canadian studies focus on youth or adolescent use. This is clearly important but adult use is as well. Establishing the link between early usage and the effects of use over an individual’s lifetime was a major objective of the study.
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Medical Cannabis May Be Effective Substitute for Opioids

MedicalResearch.com Interview with:

Philippe Lucas VP, Patient Research & Access, Tilray Graduate Researcher, Centre for Addictions Research of BC

Philippe Lucas

Philippe Lucas
VP, Patient Research & Access, Tilray
Graduate Researcher, Centre for Addictions Research of BC 

MedicalResearch.com: What is the background for this study?

Response: In 2001 Canada become one of the first nations to develop a federally regulated program to allow access to cannabis for medical purposes with the launch of the Marihuana Medical Access Regulations (MMAR). The program has undergone numerous convolutions, culminating in the establishment by Health Canada of the Marihuana for Medical Purposes Regulations (MMPR) in 2014, which was replaced by the Access to Cannabis for Medical Purposes (ACMPR) in 2016.

One of the primary changes in the new program(s) has been to move from a single Licensed Producer (LP) of cannabis to multiple large-scale Licensed Producers. This is the first comprehensive survey of patients enrolled in the MMPR/ACMPR, and with 271 complete responses, it’s the largest survey of federally-authorized medical cannabis patients to date.

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High Achieving Adolescents Less Likely To Smoke, But More Likely to Drink, Use Pot

MedicalResearch.com Interview with:
Dr. James Williams
UCL Medical School
UCL
, London, UK

MedicalResearch.com: What is the background for this study?

Response: Despite a downward trend over the last decade in the usage of particular substances amongst adolescents in the UK, smoking cigarettes, drinking alcohol and smoking cannabis remain prevalent behaviours in this demographic. These risky health behaviours present a large problem in terms of public health due to the immediate and long-term health problems they cause, as well as negative non-health outcomes such as poor educational attainment and reduced employment.

The role of academic ability in determining patterns of substance use is not clear and no study has evaluated academic ability at age 11 in relation to the onset and persistence of all three substances from early to late adolescence and into young adulthood. Our study sought to determine the association between academic ability and the onset and persistence of substance use in adolescence in a representative sample of English school pupils. This would answer for the first time whether ability was associated with ‘experimentation’ in early adolescence or if the association persists into late adolescence.

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Cannabis Use Linked To Early Drinking and Alcohol Problems

MedicalResearch.com Interview with:

Kathleen K. Bucholz, Ph.D. Professor, Department of Psychiatry Washington University School of Medicine St. Louis MO 63110-1547

Dr. Kathleen Bucholz

Kathleen K. Bucholz, Ph.D.
Professor, Department of Psychiatry
Washington University School of Medicine
St. Louis MO 63110-1547

MedicalResearch.com: What is the background for this study?

Response: We know that development of alcohol use disorder progresses through several stages of alcohol use, from beginning to drink, to engaging in problem drinking, and then to developing alcohol use disorder, but we don’t know whether the same factors are associated with each step in this progression. Stage-specific associations have implications for prevention, where targeting certain characteristics might stave off progression to the next level of alcohol involvement, potentially. That is what this particular study set out to investigate.

The data were from nearly 3600 adolescents and young adults, the majority of whom came from families with alcohol use disorder in their relatives. Thus, this sample was enriched with individuals who were at high risk for progressing to more severe stages of alcohol involvement. In studying the associations at each stage, we strengthened our analysis by defining wherever possible variables as risk factors only if they occurred before or at the same age as the particular alcohol stage. For example, we counted cannabis use as a risk factor for starting to drink only if it either preceded or occurred at the same age as taking the first drink. With this definition, we can infer that a particular factor is antecedent and not simply a correlated influence.

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Teens Used More Marijuana Following Change in Recreational Use Law

MedicalResearch.com Interview with:

Magdalena Cerda, DrPH, MPH Vice Chancellor's Chair in Violence Prevention Associate Director, Violence Prevention Research Program UC Davis Violence Prevention Research Program

Dr. Magdalena Cerda

Magdalena Cerda, DrPH, MPH
Vice Chancellor’s Chair in Violence Prevention
Associate Director, Violence Prevention Research Program
UC Davis Violence Prevention Research Program

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The potential effect of legalizing marijuana for recreational use has been a topic of considerable debate since Washington and Colorado first legalized its use for adults in 2012. Alaska, Oregon and Washington, D.C., followed suit in 2014, and voters in California, Massachusetts and Nevada approved recreational use this past November.

In our study, we examined changes in perceived risk of marijuana use, and in use of marijuana among school-attending adolescents, in Washington and Colorado, following legalization of recreational marijuana use, and compared pre- to post-legalization changes in these two states to changes in the 45 contiguous US states that had not legalized recreational marijuana use.

Marijuana use significantly increased and its perceived harm decreased among eighth- and 10th-graders in Washington state following enactment of recreational marijuana laws. There was no change in use or perceived harm among 12th graders or among similar grades in Colorado.

In particular, the data showed that legalization of recreational marijuana use significantly reduced perceptions of marijuana’s harmfulness by 14 percent and 16 percent among eighth and 10th graders and increased their past-month marijuana use by 2 percent and 4 percent in Washington state but not in Colorado. Among states without legalized marijuana use, the perceived harmfulness also decreased by 5 percent and 7 percent for students in the two grades, but marijuana use decreased by 1.3 percent and .9 percent. Among older adolescents in Washington state and all adolescents surveyed in Colorado, there were no changes in perceived harmfulness or marijuana use in the month after legalization.

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Regular Cannabis Use May Slow Down Visual Processing By Retina

MedicalResearch.com Interview with:
Dr Vincent Laprévote
Praticien Hospitalier (MD, PhD, HDR)
Pôle Hospitalo-Universitaire de Psychiatrie du Grand Nancy
Centre Psychothérapique de Nancy

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: There was evidence in animal studies showing that cannabis use could impact visual processing, but lesser was known in humans.

We showed here an association between regular cannabis use and a delay in the later stage of visual processing in the retina.

MedicalResearch.com: What should readers take away from your report?

Response: Regular cannabis use may slightly slow down the early visual processing.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Response: We have to cautiously verify our result in a larger sample. We also have to explore if this delay is present in further stages of visual processing (i. e. in the brain) and has behavioral consequences. Dr Schwitzer also just begun new researches to verify if this delay is permanent or recedes with cannabis cessation.

MedicalResearch.com: Is there anything else you would like to add?

Response: Importantly, all the participants of this research were regular cannabis users before their participation to the study. We systematically proposed cannabis cessation solutions to the participants.

MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.

Citation:

Schwitzer T, Schwan R, Albuisson E, Giersch A, Lalanne L, Angioi-Duprez K, Laprevote V. Association Between Regular Cannabis Use and Ganglion Cell Dysfunction . JAMA Ophthalmol. Published online December 08, 2016. doi:10.1001/jamaophthalmol.2016.4761

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.

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Marijuana (Cannabis) Use is Independent Predictor of Broken Heart Syndrome in Younger Men

MedicalResearch.com Interview with:

Amitoj Singh MD Chief Cardiology Fellow St. Luke’s University Health Bethlehem, Pennsylvania

Dr. Amitoj Singh

Amitoj Singh MD
Chief Cardiology Fellow
St. Luke’s University Health
Bethlehem, Pennsylvania

MedicalResearch.com: What is the background for this study?

Response: Marijuana use in steadily increasing and it is the most commonly used illicit drug in the US and worldwide. There has been a recent increase in reports of heart and vascular complications associated with its use. These include Myocardial infarctions, stroke and takotsubo.

We had two questions that we wanted to answer with our study:

a) Is there an association between marijuana use and development of Transient Regional Ventricular Ballooning [TVRB] (aka Stress Cardiomyopathy /Broken Heart Syndrome/ Takotsubo)?

b) If the above is true, what are the differences between Marijuana users (MU) and Non Marijuana Users (NMU) who developed Stress Cardiomyopathy.

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Use of Marijuana At Young Age Linked To Functional Brain Abnormalities and Lower IQ

MedicalResearch.com Interview with:

Elizabeth Osuch, M.D. Associate Professor; Rea Chair Department of Psychiatry FEMAP--London Health Sciences Centre London, ON

Dr. Elizabeth Osuch

Elizabeth Osuch, M.D.
Associate Professor; Rea Chair
Department of Psychiatry
FEMAP–London Health Sciences Centre
London, ON   

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: As a researcher and psychiatrist doing clinical work in youth aged 16-25 with mood and anxiety disorders I often see patients who are depressed and believe that using marijuana (MJ) improves their mood.  Yet they remain depressed.  This was the clinical inspiration for this brain imaging study, where we investigated emerging adults with Major Depressive Disorder (MDD).  Subject groups included patients with MDD who did and did not use MJ frequently.  Our results showed that the MDD+MJ group did not have significantly less depression than the MDD alone group, and the brain abnormalities found in MDD were not corrected by MJ use in the MDD+MJ group.  In fact, some of the brain differences were worse with the addition of MJ, while others were just different.

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Medical Marijuana Laws Linked To Lower Opioid-Related Traffic Deaths

MedicalResearch.com Interview with:

June H. Kim Doctoral candidate,Department of Epidemiology Mailman School Public Health Columbia University

June Kim

June H. Kim
Doctoral candidate,Department of Epidemiology
Mailman School Public Health
Columbia University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: A previous study indicated that states with medical marijuana laws had a reduced rate of opioid overdoses. If this is true, we’d expect to see similar reductions in opioid use associated with these laws. For this study, we used data from the FARS, a national surveillance system that records any crash events on US public roads that result in a fatality. Some states provide uniform testing of the majority of their deceased drivers, year to year. Among these states, we found that there was a lower prevalence of positive opioid toxicology tests among drivers crashing in states with an operational medical marijuana versus drivers crashing in states before a future medical marijuana law is implemented, particularly among drivers aged 21-40.

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Marijuana Use Doubles From 2002-2014

MedicalResearch.com Interview with:

Dr. Wilson Compton MD, Deputy Director National Institute on Drug Abuse

Dr. Wilson Compton

Dr. Wilson Compton MD, Deputy Director
National Institute on Drug Abuse

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The study found that overall past year marijuana use by adults in the U.S. increased by more than 30% in the past dozen years, and 10 million more people were using marijuana in 2014 than in 2002. Use of marijuana on a daily (or near daily) basis increased even more markedly. In 2002, 3.9 million adults in the U.S. reported using marijuana daily or nearly every day, and the number more than doubled to 8.4 million by 2014. Along with this increase in use, we found that U.S. adults perceptions of the potential harms from using marijuana greatly decreased. Despite scientific evidence of potential harms, adults are much less convinced about dangers associated with using marijuana. These reductions in perceived harm were strongly associated with the increases in use.

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Secondhand Pot Smoke Just As Bad For Heart As Tobacco

MedicalResearch.com Interview with:

Matthew L. Springer, Ph.D. Professor of Medicine Division of Cardiology University of California, San Francisco San Francisco, CA

Dr. Matthew Springer

Matthew L. Springer, Ph.D.
Professor of Medicine
Division of Cardiology
University of California, San Francisco
San Francisco, CA

MedicalResearch.com: What is the background for this study?

Response: We’ve known for many years that secondhand smoke from tobacco cigarettes is harmful, and the vast majority of deaths thought to result from secondhand smoke are from cardiovascular disease. However, very little has been known about cardiovascular consequences of exposure to secondhand smoke from marijuana, and people tend to mistake the lack of evidence that it is harmful, for evidence that is it not harmful. As a result, many people seem relatively unconcerned about smoking marijuana and being exposed (or exposing others) to marijuana secondhand smoke. Politicians and policy makers also seem less willing to limit where people can smoke marijuana (under legal circumstances) than tobacco. What has been lacking is research into how exposure to marijuana smoke affects cardiovascular health. It has been difficult to do such experiments because marijuana is illegal in the eyes of the federal government. However, we have been studying the harmful effects of secondhand tobacco smoke on the function of rat blood vessels, which is similar to its harmful effects on human blood vessels, and we now have studied how the function of rat blood vessels is affected by exposure to secondhand marijuana smoke.

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More Kids Now Accidentally Exposed To Edible Marijuana Poisoning

MedicalResearch.com Interview with:

George Sam Wang MD FAAP Assistant Professor of Pediatrics Section of Emergency Medicine, Medical Toxicology Department of Pediatrics University of Colorado Anschutz Medical Campus Children's Hospital Colorado

Dr. Wang

George Sam Wang MD FAAP
Assistant Professor of Pediatrics
Section of Emergency Medicine, Medical Toxicology
Department of Pediatrics
University of Colorado Anschutz Medical Campus
Children’s Hospital Colorado

MedicalResearch.com: What is the background for this study?

Response: Many states have allowed medical and now recreational marijuana. The impact on pediatric population has not been fully described.

MedicalResearch.com: What are the main findings?

Response: Unintentional exposures presenting to our children’s hospital and calls to our regional poison center significantly increased after our state allowed recreational marijuana.

MedicalResearch.com: What should readers take away from your report?

Response: Exposures in children are increasing in our state that allows medical and recreational Marijuana, many were edible products. Marijuana products should be treated like medications and household products in home and properly and safely stored. States looking to legalize marijuana need to consider safety rules and regulations during rule making processes.

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Marijuana Use May Raise Addiction Risk by Altering Brain’s Response To Rewards

MedicalResearch.com Interview with:

Mary P. Heitzeg, PhD Assistant Professor Department of Psychiatry University of Michigan

Dr. Mary Heitzeg

Mary P. Heitzeg, PhD
Assistant Professor
Department of Psychiatry
University of Michigan

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We wanted to find out if marijuana use changed the way the brain’s reward system responded to natural rewards. To probe response to natural reward, we used the chance to win some money and we observed brain response using functional magnetic resonance imaging (fMRI). We looked at brain activity when participants were 20 years old on average, and then again 2 years later and 4 years later. We found that over time marijuana use was associated with a decrease in the brain’s reward response to the chance to win money. This finding is consistent with current theories of addiction that suggest that repeated use of a substance may dampen the brain’s reward response to things normally perceived as pleasurable and this alteration may drive the individual to continue substance use.

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Marijuana Use and Short-Term Outcomes in Patients Hospitalized for Acute Myocardial

MedicalResearch.com Interview with:

Lori A. Walker, PhD University of Colorado Dept. of Medicine/Cardiology, Aurora, CO 80045

Dr. Lori Walker

Lori A. Walker, PhD
University of Colorado
Dept. of Medicine/Cardiology,
Aurora, CO 80045

MedicalResearch.com: What is the background for this study?

Dr. Walker: Marijuana use is increasing worldwide, in part due to local changes in legal status. Concomitantly, there has been an increase in case studies reporting adverse cardiac events associated with marijuana use. However, little is known about the impact of marijuana use on cardiovascular outcomes. Therefore, the aim of this study was to quantify outcomes in a retrospective analysis of hospitalized patients with acute myocardial infarction (AMI) with reported marijuana use at the time of admission. Administrative hospital records for 8 states between 1994-2013 were screened for adults (age > 18 years) with a diagnosis of AMI. Clinical profiles and outcomes in patients with reported marijuana use were compared to patients with no reported marijuana use. The primary outcome was a composite of death, mechanical ventilation, cardiac arrest, intraaortic balloon pump (IABP) placement, or shock. Secondary outcomes were components of the primary outcome plus coronary angiography, percutaneous coronary intervention (PCI), and ST segment elevation myocardial infarction (STEMI).

MedicalResearch.com: What are the main findings?

Dr. Walker: Associations between marijuana, patient characteristics, and outcomes were determined using step-forward multivariate logistic regression which revealed that marijuana using patients were more likely to be younger, African-American and to use tobacco, cocaine/methamphetamine or alcohol than the control group. Accounting for age, race, and other risk factors such as coronary artery disease, hypertension, tobacco, hyperlipidemia and diabetes mellitus, multivariate logistic regression suggested that marijuana-using patients were less likely to die in-hospital (OR 0.83, 95% CI 0.68-1.00) post AMI but more likely to require mechanical ventilation (OR 1.19, 95% CI 1.06-1.33).

MedicalResearch.com: What should clinicians and patients take away from your report?

Dr. Walker: Clinicians and patients should be aware that there are likely direct effects of cannabinoids on the cardiovascular system. This preliminary study underscores the need for further basic science research.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Dr. Walker: There is a strong need for basic science research aimed at elucidating the signaling pathways evoked by cannabinoids in both cardiac and vascular smooth muscle. Additionally, prospective clinical research aimed at quantifying the effects of marijuana use on cardiac rhythm in healthy patients and those with existing cardiac disease is essential.

MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.

Citation:

Abstract presented at April 2016 ACC

Marijuana Use and Short-Term Outcomes in Patients Hospitalized for Acute Myocardial Infarction Cecelia P. Johnson-Sasso, David Kao, Lori A. Walker, University of Colorado, Aurora, CO, USA
Cecelia P. Johnson-Sasso; David Kao; Lori A. Walker

J Am Coll Cardiol. 2016;67(13_S):569-569. doi:10.1016/S0735-1097(16)30570-8

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.

More Medical Research Interviews on MedicalResearch.com

Lori A. Walker, PhD (2016). Marijuana Use and Short-Term Outcomes in Patients Hospitalized for Acute Myocardial MedicalResearch.com

Marijuana Use Doubles Over Decade

Deborah S. Hasin, Ph.D. Professor of Epidemiology Columbia University New York, New York 10032MedicalResearch.com Interview with:
Deborah S. Hasin, Ph.D.
Professor of Epidemiology
Columbia University
New York, New York 10032

 Medical Research: What is the background for this study? What are the main findings?

Dr. Hasin: This study is based on data from two large-scale national surveys conducted over an eleven-year period that are designed to provide information on many health-related conditions in U.S. adults, including use of marijuana and other substances, changes over time in the prevalence of marijuana users, changes over time in the prevalence of disorders such as marijuana abuse and dependence, and the correlates and predictors of those disorders. The main findings of the study are that between 2001-2002 and 2012-2013, the prevalence of marijuana users in the United States adult general population more than doubled, from 4.1% to 9.5%, while the prevalence of adults with marijuana use disorder (abuse or dependence) also increased substantially, from 1.5% to 2.9% of American adults. About three in ten adult marijuana users met criteria for a marijuana use disorder. The findings are consistent with other studies showing increases in rates of marijuana-related harms over the same general time period.

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High School Students Smoking More Pot Than Tobacco

Dr. Italia V. Rolle, PhD and Dr. Tim McAfee, MD Office on Smoking and Health National Center for Chronic Disease Prevention and Health Promotion CDC

Marijuana plant (Cannabis sativa)

MedicalResearch.com Interview with:
Dr. Italia V. Rolle, PhD and Dr. Tim McAfee, MD
Office on Smoking and Health
National Center for Chronic Disease Prevention and Health Promotion
CDC

Medical Research: What is the background for this study? What are the main findings?

Response: Since 2010, the proportion of U.S. 12th grade students who used marijuana during the preceding 30 days (21.4%) has surpassed the proportion who used cigarettes (19.2%). Negative outcomes associated with cigarette and marijuana use include addiction to one or both substances and diminished cognitive function, which can lead to lower academic achievement. CDC analyzed data from the 1997–2013 national Youth Risk Behavior Surveys (YRBS) among U.S. non-Hispanic white (white), non-Hispanic black (black), and Hispanic students in grades 9–12 to examine trends in the prevalence of current

1) exclusive cigarette or cigar use,
2) exclusive marijuana use, and
3) any use of the three products.

CDC further examined the prevalence of current marijuana use among current users of cigarettes or cigars. During 1997–2013, exclusive cigarette or cigar use declined overall by 64%, from 20.5% to 7.4% (p<0.01). However, exclusive marijuana use more than doubled overall from 4.2% to 10.2% (p<0.01). Any cigarette, cigar, or marijuana use decreased overall from 46.1% to 29.9% (p<0.01), whereas marijuana use among cigarette or cigar users increased from 51.2% to 62.4%. Considerable increases were identified among black and Hispanic students toward the end of the study period for exclusive marijuana use and marijuana use among cigarette or cigar users. Increased exclusive marijuana use and use of marijuana among cigarette or cigar users could undermine success in reducing tobacco use among youths.

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Smaller Gender Gap in Adolescent Marijuana Use

MedicalResearch.com Interview with:Renee M. Johnson, PhD, MPH Assistant Professor Johns Hopkins Bloomberg School of Public Health, Dept. of Mental Health Deputy Director, Drug Dependence Epidemiology Training Program (DDET) Baltimore MD
Renee M. Johnson, PhD, MPH
Assistant Professor
Johns Hopkins Bloomberg School of Public Health, Dept. of Mental Health
Deputy Director, Drug Dependence Epidemiology Training Program (DDET)
Baltimore MD

Medical Research: What is the background for this study? What are the main findings?

Dr. Johnson: There has been a lot of policy change with regard to marijuana. Several states have enacted laws regarding medical marijuana and decriminalization, and now four states and the District of Columbia have legalized use for adults. Along with these policy changes, there’s been concern that adolescent marijuana use would skyrocket. This prompted me to think about what’s happened over the past 15 years, and so I decided to examine past 15-year trends in adolescent marijuana use among US high school students.

Our research team analyzed data from the Centers for Disease Control and Prevention’s Youth Risk Behavior Surveillance Study, or YRBS. It is a nationally-representative survey of high school students. A lot of the information we have about adolescents’ risk behavior comes from the YRBS.

What we found is that marijuana use among US high school students has gone down over the time period. In 1999, 47% of high school students reported lifetime use of marijuana. By 2013, 41% reported lifetime use. Use was lowest in 2009, with 37% of high school students reporting lifetime use. The increase in use from 2009 to 2013 was not statistically significant, so we aren’t sure whether it represents random fluctuation or whether it indicates a reversal in trend.

We also found that gender differences have gotten smaller over the time period, reflecting a real change. Boys have historically had higher rates of use, but that’s changing. In 1999, 51% of boys and 43% of girls reported lifetime marijuana use. By 2013, 42% of boys and 39% of girls reported lifetime use.

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Marijuana May Increase Risk of Pre-Diabetes

Mike Bancks, MPH NHLBI Cardiovascular Disease Epidemiology & Prevention Pre-doctoral Fellow University of Minnesota School of Public HealthMedicalResearch.com Interview with:
Mike Bancks, MPH

NHLBI Cardiovascular Disease Epidemiology & Prevention Pre-doctoral Fellow
University of Minnesota School of Public Health
banck005@umn.edu

Medical Research: What is the background for this study? What are the main findings?

Response: We chose to research this topic because marijuana is the most commonly used illicit drug in the United States and use can be expected to increase as the effort to legalize marijuana for recreational and medicinal use grows. We found that individuals who reported using marijuana in excess of 100 times during young adulthood had 40% greater risk for developing prediabetes by middle adulthood. However, we did not find an association between marijuana use and overt diabetes during this same period in adulthood, suggesting that marijuana use may be a risk factor for the early stage of diabetes.

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Up to 70% of Marijuana Users Also Use Tobacco With Complex Results

Francesca M. Filbey PhD School of Behavioral and Brain Sciences Center for Brain Health University of Texas at Dallas Dallas, TXMedicalResearch.com Interview with:
Francesca M. Filbey PhD
School of Behavioral and Brain Sciences
Center for Brain Health University of Texas at Dallas
Dallas, TX

Medical Research: What is the background for this study? What are the main findings?

Dr. Filbey: Most studies exclude tobacco users from participating, but 70% of marijuana users also use tobacco. We were interested in investigating the combined effects of marijuana and tobacco. Our research targeted the hippocampus because smaller hippocampal size is associated with marijuana use. We chose to study short term memory because the hippocampus is an area of the brain associated with memory and learning. The main finding was surprising. The smaller the hippocampus in the marijuana plus nicotine user, the greater the memory performance. We expected the opposite, which was true of the non-using control group. Continue reading

Most Adults Who Use Marijuana Smoke It

Gillian Schauer, PhD, MPH Lead author and Contractor CDC’s Office on Smoking and HealthMedicalResearch.com Interview with:
Gillian Schauer, PhD, MPH
Lead author and Contractor
CDC’s Office on Smoking and Health

Medical Research: What is the background for this study? What are the main findings?

Dr. Schauer:
Marijuana is the most commonly used federally illicit drug in the United States. State-level policy change legalizing marijuana or one of its constituents for recreational or medical use is increasing. Currently, 23 states and DC have legalized medical use of marijuana. Four states (Alaska, Colorado, Oregon and Washington) and the District of Columbia have legalized recreational and medical use of marijuana.

  • This paper helps fill two important knowledge gaps. It describes how US adults are using marijuana—for example, whether they smoke it, eat it, or use it in a vaporizer—and it describes whether they report using it for medical reasons or for recreational reasons, or both. Data come from the 2014 Summer Styles national consumer online panel survey (sample size of 4,269 adults), and have been published in the American Journal of Preventive Medicine.
  • Nationally, marijuana is primarily consumed in combusted (smoked) form. In 2014, among adults who used marijuana in the past 30 days, 92.1% of adults said they smoked it, 16.1% ate or drank it, and 7.6% used a vaporizer or other electronic device.
  • Among adults who used marijuana in the past 30 days, 10.5% say they used it only for medical reasons, 53.4% used it only for recreational reasons, and 36.1% used it for both.

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Synthetic Cannabinoids Put Teenagers at Cardiac Risk

MedicalResearch.com Interview with:
Bradley C. Clark, MD
Pediatric Cardiology Fellow – 3rd Year
Division of Cardiology
Children’s National Health System
Washington, DC 20010

Medical Research: What is the background for this study? What are the main findings?

Dr. Clark: After consulting on multiple pediatric emergency room patients with K2 (synthetic cannabinoid) ingestion and electrocardiogram (ECG) abnormalities, my co-authors and I decided that it was worth taking a more detailed look at the potential cardiac effects of synthetic cannabinoids.

We did a retrospective chart review and discovered a total of 8 patients in a 3 year period (2011 – 2014) at our institution with reported synthetic cannabinoid ingestion and concern for myocardial injury.  There were 3 individuals with evidence of ECG abnormalities in a segmental pattern with increased cardiac enzyme levels (troponins).  The other 5 individuals had ECG abnormalities either without troponin elevations or were not specifically tested.  Each individual that had an echocardiogram performed had normal intracardiac anatomy with normal biventricular systolic function.

Given the elevated troponin levels and ECG abnormalities, there was a suspicion for myocardial ischemia in this small subset of patients without meeting specific criteria for myocardial infarction.  Interestingly, these individuals had completely normal echocardiograms and had no other potential cause of myocardial ischemia discovered by history.  Additionally, these were all teenage pediatric patients with documented K2 exposure without evidence of exposure to illegal substances.

K2 and other synthetic cannabinoids are known to cause analgesia and euphoria and can lead to a lack of symptomatology.  Therefore, individuals with synthetic cannabinoid ingestion may not complain of the prototypical cardiac symptoms (chest pain, shortness of breath, palpitations) and may not have the workup to diagnose potential myocardial ischemia.

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Higher Adolescent Marijuana Usage In States That Legalized Pot

Deborah S. Hasin, Ph.D. Professor of Epidemiology Columbia University New York, New York 10032MedicalResearch.com Interview with:
Deborah S. Hasin, Ph.D.

Professor of Epidemiology
Columbia University
New York, New York 10032

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Hasin: The background for the study was the need to identify the causes of the marked increase in marijuana use among U.S. adolescents over the last several years, given that early adolescent marijuana use leads to a number of adverse health and psychosocial consequences, including cognitive decline, into adulthood.

We had two main findings from the study:

  1. A comparison of the rates of adolescent marijuana use between states that ever passed a medical marijuana law and those that did not revealed that states with such laws had higher rates of teen marijuana use, regardless of when they passed the law; and
  2. When we compared the rates of teen marijuana use in these states before and after passage of the laws, we did not find a post-passage increase in the rates of teen marijuana use. This suggests that some common factor may be causing both the laws to be passed and the teens to be more likely to smoke marijuana in the states that passed these laws.

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Dramatic Increase In Young Children Accidentally Exposed To Pot

Dr. Gary Smith MD, DrPH Center for Injury Research and Policy Nationwide Children's Hospital Columbus, OhioMedicalResearch.com Interview with:
Dr. Gary Smith MD, DrPH

Center for Injury Research and Policy
Nationwide Children’s Hospital
Columbus, Ohio

Medical Research: What is the background for this study? What are the main findings?

Dr. Smith: As of January 2015, 23 states and Washington D.C. have legalized marijuana for medical use. Four of those same states and Washington D.C. have also voted to legalize marijuana for recreational use. The debate about legalization often focuses on health effects among adults, economic benefits, and crime rates. Lost in the discussion is the potential harm to young children from unintentional exposure to marijuana.

The study found that the rate of marijuana exposure among children 5 years of age and younger rose 147.5 percent from 2006 through 2013 across the United States. The rate increased almost 610 percent during the same period in states that legalized marijuana for medical use before 2000.

In states that legalized marijuana from 2000 through 2013, the rate increased almost 16 percent per year after legalization, with a particular jump in the year that marijuana was legalized. Even states that had not legalized marijuana by 2013 saw a rise of 63 percent in the rate of marijuana exposures among young children from 2000 through 2013.

Most children were exposed when they swallowed marijuana – that may be related to the popularity of marijuana brownies, cookies and other foods.

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Case Reports Link Marijuana With Increased Stroke Risk

Daniel G. Hackam, MD, PhD, FRCPC Division of Clinical Pharmacology, Department of Medicine Western University, London, Ontario, Canada.MedicalResearch.com Interview with:
Daniel G. Hackam, MD, PhD, FRCPC
Division of Clinical Pharmacology, Department of Medicine
Western University, London, Ontario, Canada.

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Hackam: Stroke is thought to be related to marijuana use; however, this belief rests largely on case reports. These case reports have never been
evaluated by causality criteria. After performing such an analysis, I
showed that many case reports meet stringent causality criteria, and
therefore stroke is more likely to result from marijuana use.

MedicalResearch: What should clinicians and patients take away from your report?

Dr. Hackam: Stroke is related to marijuana consumption. After an index stroke, consuming marijuana again is linked to recurrent stroke.

MedicalResearch: What recommendations do you have for future research as a result of this study?

Dr. Hackam: We badly need a large, prospective observational study to test the association of marijuana use with stroke.

Citation:

Cannabis and Stroke: Systematic Appraisal of Case Reports

Stroke. 2015;46:852-856 published online before print February 19 2015, doi:10.1161/STROKEAHA.115.008680

MedicalResearch.com Interview with: Daniel G. Hackam, MD, PhD, FRCPC (2015). Case Reports Link Marijuana With Increased Stroke Risk 

 

Secondhand Marijuana Smoke May Be As Bad For You As Tobacco

Matthew L. Springer, Ph.D.  Associate Professor of Medicine Division of Cardiology Cardiovascular Research Institute Broad Center of Regeneration Medicine and Stem Cell Research Center for Tobacco Control Research & Education Helen Diller Family Comprehensive Cancer Center University of California, San Francisco   MedicalResearch.com Interview with:
Matthew L. Springer, Ph.D
.
Associate Professor of Medicine
Division of Cardiology
Cardiovascular Research Institute
Broad Center of Regeneration Medicine and Stem Cell Research
Center for Tobacco Control Research & Education
Helen Diller Family Comprehensive Cancer Center
University of California, San Francisco    

Medical Research: What is the background for this study? What are the main findings?

Dr. Springer: The general public is aware that cigarette secondhand smoke is harmful. However, many people who actively avoid tobacco secondhand smoke don’t feel the need to avoid marijuana secondhand smoke; they don’t consider it harmful because there’s no nicotine and because we who tell them to avoid tobacco smoke don’t tell them to avoid marijuana smoke.  However, secondhand smoke from tobacco and marijuana is very similar in chemical composition (4000-7000 chemicals depending on whom you ask), aside from the nicotine and the THC (the psychoactive drug in marijuana).

We and others have shown that brief exposure to tobacco secondhand smoke, such as 30 minutes, at real-world levels impairs vascular function in humans.  We developed a way to study vascular function (measured as arterial flow-mediated dilation; FMD) in living rats, and recently published that even one minute of sidestream smoke from the burning tips of tobacco cigarettes, a well-accepted model for secondhand smoke, is enough to start detecting impairment of FMD.  The main findings of the current study are that in laboratory rats, FMD was substantially impaired by a 30 minute exposure to marijuana secondhand smoke, when measured 10 minutes after the end of exposure.  Impairment was comparable to that resulting from exposure to tobacco sidestream smoke, although whereas impairment from tobacco smoke was temporary and had normalized by 40 minutes later, FMD was still impaired 40 minutes after the end of exposure to marijuana smoke.  Smoke from marijuana lacking THC still impaired FMD, showing that  Continue reading

Marijuana May Be Protective Against Traumatic Brain Injury

David Plurad, MD Los Angeles Biomedical Research In
MedicalResearch.com Interview with:

David Plurad, MD
Los Angeles Biomedical Research Institute.


Medical Research: What are the main findings of the study?
Based on a survey of patients with traumatic brain injuries, a group of Los
Angeles Biomedical Research Institute researchers found those who tested
positive for tetrahydrocannabinol (THC), the active ingredient in marijuana, were more likely to survive than those who tested negative for the illicit substance.

We surveyed 446 patients who were admitted to a major urban hospital with
traumatic brain injuries between Jan. 1, 2010, and Dec. 31, 2012, who were
also tested for the presence of THC in their urine. We found 82 of the
patients had THC in their system. Of those, 2.4% died. Of the remaining
patients who didn’t have THC in their system, 11.5% died.

While most – but not all – the deaths in the study can be attributed to the
traumatic brain injury itself, it appears that both groups were similarly
injured. The similarities in the injuries between the two groups led to the
conclusion that testing positive for THC in the system is associated with a
decreased mortality in adult patients who have sustained traumatic brain
injuries.
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Adolescent Cannabis Use Linked To Young Adult Adverse Outcomes

MedicalResearch.com Interview with:
Edmund Silins PhD, Research Fellow
National Drug and Alcohol Research Centre
UNSW Medicine University of New South Wales
Sydney  Australia

Medical Research: What are the main findings of the study?

Dr. Silins: There were three particularly interesting aspects to the findings.

  • Firstly, we found clear and consistent associations between adolescent cannabis use and the young adult outcomes investigated.
  • Secondly, there was evidence of a dose-response effect such that the more frequently adolescents used cannabis the more likely they were to experience harms later in life.
  • Thirdly, for most outcomes, these associations remained even after taking into account a wide range of other factors which might potentially explain them.

The adverse effects were greatest for daily cannabis users. Specifically, adolescents who were daily cannabis users were, by the age of 25, more than 60% less likely to complete high school or obtain a university degree, seven times more likely to have attempted suicide, 18 times more likely to have been cannabis dependent, and eight times more likely to have used other illicit drugs, than adolescents who had never used the drug.
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Brief Screening Guages Teenage Substance Abuse risk

Sharon Levy, M.D., M.P.H. Director, Adolescent Substance Abuse Program Assistant Professor in Pediatrics Boston Children’s HospitaMedicalResearch.com Interview with:
Sharon Levy, M.D., M.P.H.
Director, Adolescent Substance Abuse Program
Assistant Professor in Pediatrics
Boston Children’s Hospital

 
Medical Research: What are the main findings of the study?

Dr. Levy: We found that questions that asked about the frequency of alcohol, tobacco and drug use accurately triaged adolescents into “risk categories”.  In other words, kids who reported using alcohol or marijuana “once or twice” last year were unlikely to have a substance use disorder, those who reported “monthly” use were very likely to meet diagnostic criteria for a “mild” or “moderate” substance use disorder while those who reported use weekly or more were very likely to meet diagnostic criteria for a “severe” substance use disorder.
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Does Marijuana Increase Stroke Risk in Young Adults?

MedicalResearch.com Interview with:
Tara Dutta M.D.
Vascular Neurology Fellow
University of Maryland Medical Center

MedicalResearch: What are the main findings of the study?

Dr. Dutta: We analyzed data from the Stroke Prevention in Young Adults Study in order to evaluate for an association between self-reported marijuana use and ischemic stroke.   1,101 cases and 1,154 age, gender, and race-matched controls, aged 15-49 years old, were recruited from the greater Baltimore-Washington area between 1992 and 2008. Interviews were conducted to assess for various potential stroke risk factors, including illicit drug, alcohol, and tobacco use. Individuals reporting use of vasoactive illicit drugs, including cocaine and amphetamines, were excluded, yielding 751 cases and 813 controls. Logistic regression analysis was used to determine the association between marijuana use and ischemic stroke, adjusting for age, gender, race, current tobacco use, current alcohol use, hypertension, and diabetes.

We did not find a positive association between marijuana use and ischemic stroke risk in our population of young-onset stroke patients compared to matched controls, even after controlling for current tobacco and alcohol use, hypertension, and diabetes.   A statistically significant inverse relationship was observed between remote use (defined as any use over one year ago) and stroke risk (adjusted OR 0.77, CI 0.61-0.98, p = 0.03). We also looked to see whether recent use (in the past 30 days), and particularly recent heavy use, was associated with ischemic stroke risk as has been suggested in the medical literature. Though our data did not show this association, the number of patients reporting recent use in our study was very small­­­­­­­.

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Ischemic Stroke after Synthetic Marijuana Use

W. Scott Burgin, MD Professor and Chief Cerebrovascular Division Director, Comprehensive Stroke Center Department of Neurology USF College of Medicine Tampa General Hospital Stroke CenterMedicalResearch.com Interview with:
W. Scott Burgin, MD
Professor and Chief, Cerebrovascular Division
Director, Comprehensive Stroke Center
Department of Neurology
USF College of Medicine
Tampa General Hospital Stroke Center.

MedicalResearch.com What are the main findings of the study?

Dr. Burgin: Two cases of stroke, of embolic appearance, shortly after smoking synthetic marijuana.
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HIV plus Hepatitis C : Marjuana Did Not Worsen Liver Disease

Marina Klein, MD, MSc, FRCP(C) Associate Professor of Medicine McGill University Health Centre Division of Infectious Diseases and Chronic Viral Illness Service 3650 Saint Urbain Montreal, Quebec H2X 2P4MedicalResearch.com Interview with:

Marina Klein, MD, MSc, FRCP(C)
Associate Professor of Medicine
McGill University Health Centre
Division of Infectious Diseases and Chronic Viral Illness Service
3650 Saint Urbain
Montreal, Quebec H2X 2P4

Disease in HIV–Hepatitis C Coinfection: A Longitudinal Cohort Analysis               

MedicalResearch.com: What are the main findings of the study?

Dr. Klein: We showed that people with HIV and hepatitis C infection who smoked marijuana did not tend to progress more rapidly to liver fibrosis, liver cirrhosis or end-stage liver disease, even with increasing numbers of joints smoked per week. Previous studies that reported that marijuana was harmful to the liver were likely biased because they did not ensure that marijuana smoking occurred before the development of liver problems.

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