MedicalResearch.com Interview with:
Ryan Vandrey, Ph.D.
Associate Professor
Behavioral Pharmacology Research Unit
Johns Hopkins University School of Medicine
Baltimore, MD 21224
Medical Research: What is the background for this study? What are the main findings?
Dr. Vandrey: The background for the study was that I have had several conversations with individuals that led me to believe that there was insufficient regulation of products of all types being sold in medical cannabis dispensaries. In order to evaluate that, we needed to do a study. We decided to test edible products because that is a growing market, and, because it involves some level of manufacturing, there is greater chance for dose variability and inaccuracy. The main finding was that the majority of products were purchased from retail stores selling cannabis products for medical use were significantly mislabeled with regards to the dose of THC and other cannabinoids.
MedicalResearch.com Interview with:
Vanita Ahuja, MD, MPH
Department of General Surgery
York Hospital, York, Pennsylvania
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Ahuja: Robotic-assisted surgery has been slowly accepted within the medical community. Felger et al. (1999), Falk et al. (2000), and Loumet et al. (2000) state that specific to cardiac surgery, the advantages of the robot in coronary artery bypass grafting (CABG) and valvular operations were demonstrated with increased visualization, ease of harvest, and quality of vascular anastomoses as early as 1999. However, Giulianotti, et al. (2003), Morgan et al. (2005), and Barbash et al. (2010) suggest that although safety and efficacy are supported, it is not conclusive yet that robot-assisted surgery is cost-effective, given the high cost of the robot itself, longer operating times, and the short life of the robotic instruments. The purpose of our paper was to compare outcomes of complications, length of stay (LOS), actual cost, and mortality between non-robotic and robotic-assisted cardiac surgery.
In general surgery and subspecialties, the use of the robot has increased significantly over the past few years. It has been noted that robotic surgery improves on laparoscopic surgery by providing increased intra-cavity articulation, increased degrees of freedom, and downscaling of motion amplitude that may reduce the strain on the surgeon.
The biggest growth in robotic surgery has been seen in the fields of gynecology and urology. Recently, Wright et al. reported an increase in robotic assisted hysterectomy from 0.5 percent of the procedures in 2007 compared to 9.5 percent in 2010 for benign disease. In their study, robotic assisted surgery had similar outcomes to laparoscopic surgery but higher total cost of $2,189 more per case. In urologic surgery, Leddy et al. reported in 2010 that radical prostatectomy remains the biggest utilization of robotic assisted surgery in urology with 1% in 2001 to 40% of all cases in 2006 performed in the United States.
Utilizing a nationwide database from 2008-2011, subjects were propensity matched by 14 patient characteristics to reduce selection bias in a retrospective study. The patients were then divided into three groups by operation types: valves, vessels and other type. Univariate analysis revealed that robotic-assisted surgery, compared to non-robotic surgery, had higher cost ($39,030 vs. $36,340), but lower LOS (5 vs. 6 days) and mortality (1% vs. 1.9%, all p<0.001). For those who had one or more complications, robotic-assisted cardiac surgery had fewer complications (27.2%) to non-robotic cardiac surgery (30.3%, p < .001).
MedicalResearch.com Interview with:
Dr. Ayalew Tefferi, M.D.
Department of Medicine,
Mayo Clinic
Rochester, Minnesota
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Tefferi: William Vainchenker discovered and reported an activating JAK2 mutation (JAK2V617F) in myelofibrosis and related myeloproliferative neoplasms in 2005 (Nature. 2005;434:1144-1148). This seminal observation led to the recognition of activated JAK-STAT as the potential disease-driving pathway in myeloproliferative neoplasms and development of several JAK inhibitors, including fedratinib, ruxolitinib and momelotinib, for treatment of myelofibrosis. In phase 2 studies, these JAK inhibitors showed similar activity in alleviating constitutional symptoms and reducing spleen size. However, none of them were able to induce complete or partial remissions or reversal of bone marrow fibrosis or significant lowering of JAK2 mutant allele burden. A subsequent phase 3 study provided the information required for FDA approval of ruxolitinib and the current phase 3 study was meant to do the same for fedratinib.
MedicalResearch.com Interview with:
Dr. Stacy Loeb, MD, MSc
Department of Urology, Population Health,
and Laura and Isaac Perlmutter Cancer Center
New York University, New York
Medical Research: What is the background for this study?
Dr. Loeb: A paper published last year suggested a relationship between use of (Viagra) and melanoma. That study had only 142 cases of melanoma, and of these men 14 had used sildenafil. This study got a lot of publicity leading numerous patients to express concern over whether erectile dysfunction drugs could cause melanoma.
Our goal was to look more closely at this issue in a larger population from Sweden (including 4065 melanoma cases of whom 435 used any type of erectile dysfunction drug- Viagra, as well as Levitra and Cialis). Sweden has a national health system so we were able to access prescription records for men across the entire country, which we linked to the national registries for melanoma and basal cell skin cancer.
MedicalResearch.com Interview with:
Sean D. Pokorney, MD, MBA
Division of Cardiology, Duke University Medical Center
Duke Clinical Research Institute, Durham, North Carolina
Medical Research: What is the background for this study?
Dr. Pokorney: About 350,000 people die of sudden cardiac death in the US each year. Patients who have weakened heart function, particularly those with heart muscle damage as a result of a heart attack, are more likely to experience sudden cardiac death. Defibrillators have been around since the 1980s, and have prolonged countless lives. A previous study showed that 87% of patients who had a cardiac arrest were eligible for an implantable-cardioverter defibrillator (ICD) beforehand but did not get an ICD implanted prior to their arrest. The timing of ICD implantation is critical, as studies have not found a benefit to ICD implantation early after myocardial infarction (MI). Guidelines recommend primary prevention ICD implantation in patients with an EF ≤ 35% despite being treated with optimal medical therapy for at least 40 days after an MI. Given the need to wait for at least 40 days after an MI, ICD consideration is susceptible to errors of omission during the transition of post-MI care between inpatient and outpatient care teams. Also, the benefit of ICDs remains controversial among older patients, as these patients were underrepresented in clinical trials.
Medical Research: What are the main findings?
Dr. Pokorney: We looked at Medicare patients discharged from US hospitals after a heart attack between 2007 and 2010. We focused on those patients who had weak heart function, and this left us with a little over 10,300 patients from 441 hospitals for our study. This was an older patient population with a median age of 78 years. We looked to see how many of these patients got an ICD within the first year after MI, and how many patients survived to 2 years after their heart attack. Only 8% of patients received an ICD within 1 year of their heart attack. ICD implantation was associated with a third lower risk of death within 2 years after a heart attack, and this was consistent with the benefit that were seen in the randomized clinical trials. Importantly, 44% of the patients in our study were over 80 years old, and we found that the relationship between ICD use and mortality was the same for patients over and under age 80 years. Increased patient contact with the health care system through early cardiology follow-up or re-hospitalization for heart failure or MI was associated with higher likelihood of ICD implantation. Rates of ICD implantation remained around 1 in 10 patients within 1 year of MI even among patients with the largest heart attacks and the weakest hearts (lowest ejection fractions), who were least likely to have improvement in their heart function over time. Similarly, even after excluding patients at highest risk for non-arrhythmic death (prior cancer, prior stroke, and end stage renal disease), ICD implantation rates remained around 1 in 10 patients.
MedicalResearch.com Interview with: Dr. Yang Lin on behalf of all authors Department of Surgery, Division of Public Health Sciences Siteman Cancer Center, Washington University School of Medicine St Louis, Missouri Medical Research: What is the background for this study? What are the main findings? Dr. Lin: Overweight, obesity and associated chronic conditions are largely driving the...
MedicalResearch.com Interview with:
Isabelle Bedrosian, M.D., F.A.C.S.
Associate Professor, Department of Surgical Oncology, Division of Surgery,
Medical Director, Nellie B. Connelly Breast Center
The University of Texas MD Anderson Cancer Center, Houston, TX
Medical Research: What is the background for this study? What are the main findings?
Dr. Bedrosian: There have been a number of reports on the rates of Breast Conserving Therapy (BCT) and mastectomy among women with early stage breast cancer. These reports have been discordant, with some suggesting that index mastectomy rates have increased and others suggestion Breast Conserving Therapy rates have actually increased. We hypothesized that these differences in reporting may be due to data source (ie tertiary referral centers vs population based studies) and turned to the NCDB, which captures 70% of cancer cases in the US and as such provides us with the most comprehensive overview on patient treatment patterns.
MedicalResearch.com Interview with:
Samuel Pannick, MA, MBBS, MRCP
Imperial Patient Safety Translational Research Center, National Institute for Health Research and Imperial College London
West Middlesex University Hospital National Health Service Trust Middlesex, England
Medical Research: What is the background for this study? What are the main findings?
Response: Improving the quality of general medical ward care is a recognized healthcare priority internationally. Ward teams have been encouraged to structure their work more formally, with regular interdisciplinary team meetings and closer daily collaboration with their colleagues. Some early studies suggested that these changes might benefit patients, and help ward teams work more efficiently. However, team interventions on medical wards have been reported with numerous different outcome measures, and prior to this study, it was unclear what their objective benefits were.
We showed that there is little agreement on the objective outcomes that best reflect the quality of interdisciplinary team care on general medical wards. Changes to interdisciplinary care aren’t reflected in the outcome measures that researchers choose most often, like early readmission rates or length of stay. Complications of care - although harder to record - might have more promise as a measure of the quality of inpatient team care in these specific medical areas.
MedicalResearch.com Interview with:
Ron Postuma, MD, MSc
Associate Professor
Department of Neurology
Montreal General Hospital
Montreal, Quebec
Medical Research: What is the background for this study? What are the main findings?
Dr. Postuma: The background is that we often think about Parkinson’s Disease as a single disease. However, every clinician knows that there is a great deal of variability from patient to patient. If we can understand the main aspects that separate patients into groups, we can target therapy better.
The analysis used a semi-automated means to divide Parkinson’s patients into groups, using extensive information about motor and non-motor aspects of disease. We found that the non-motor symptoms, especially cognition, sleep disorders, and blood pressure changes were the most powerful predictors of which group a patient would be in. Based on these non-motor (and some motor aspects), the most accurate way to divide patients was into three groups - diffuse (many non-motor symptoms), pure motor, and intermediate (halfway between the other). We then followed patients over time. The diffuse group had, by far, the worse prognosis. This was not only for the non-motor aspects, but the motor as well.
MedicalResearch.com Interview with:
Joseph A. Ladapo, MD, PhD
Assistant Professor of Medicine
Section on Value and Effectiveness
Department of Population Health
NYU Langone School of Medicine
Medical Research: What is the background for this study? What are the main findings?
Dr. Ladapo: Routine tests before elective surgery are largely considered to be of low value, and they may also increase costs. In an attempt to discourage their use, two professional societies released guidance on use of routine preoperative testing in 2002. We sought to examine the long-term national effect of these guidelines from the American College of Cardiology/American Heart Association and the American Society of Anesthesiologists on physicians' use of routine preoperative testing. While we found that overall rates of routine testing declined across several categories over the 14-year study period, these changes were not significant after accounting for overall changes in physicians’ ordering practices. Our findings suggest that professional guidance aimed at improving quality and reducing waste has had little effect on physician or hospital practice.
MedicalResearch.com Interview with: Kristina H. Lewis, MD, MPH, SM Kaiser Permanente Georgia, Center for Clinical and Outcomes Research, Atlanta Department of Population Medicine Harvard Medical School/Harvard Pilgrim Health Care Institute, Boston, Massachusetts Medical Research: What is the background for this study? Dr. Lewis: The prevalence of severe obesity (BMI ≥40 kg/m2) in the U.S. is rising. This is...
MedicalResearch.com Interview with:
Louise Sun, MD SM FRCPC
Assistant Professor Department of Anesthesiology,
University of Ottawa Staff | Division of Cardiac Anesthesiology
University of Ottawa Heart Institute
Medical Research: What is the background for this study? What are the main findings?
Dr. Sun: Preoperative testing provides important information for perioperative
planning and decision-making. However, given the rapid increase in health
care costs, there has been growing emphasis on the more rational use of
resources and thus the need to better understand the utilization patterns
of specific tests. Preoperative pulmonary function tests (PFTs) are
important in helping perioperative physicians identify patients at risk
for postoperative pulmonary complications, but few appropriate use
guidelines exist for this test. We conducted a population-based study
using linked administrative databases in Ontario, Canada to describe
temporal trends in preoperative pulmonary function tests
and assess whether the recent 2006 American College of Physicians (ACP) guidelines on risk assessment and prevention of postoperative pulmonary complications for non-cardiothoracic surgery influenced these trends.
We examined 511,625 individuals undergoing non-cardiothoracic surgery, amongst whom
3.6% underwent preoperative pulmonary function tests while 3.3% had non-operative PFTs.
Preoperative pulmonary function tests rates decreased over the study period and following the 2006 ACP guidelines while non-operative rates remained stable. By 2013,
preoperative pulmonary function tests were performed in fewer than 8% of Ontario patients with risk factors for pulmonary complications, while preoperative testing
rates among individuals without known respiratory disease had approached
rates seen in the non-operative setting. The decreasing preoperative pulmonary function tests rates contrast starkly against concurrent increases in rates of other
perioperative interventions such as preoperative anesthesia consultations
and stress testing.
MedicalResearch.com Interview with:
Jordan M. Cloyd, MD
Department of Surgery
Stanford University
Stanford, California
Medical Research: What is the background for this study? What are the main findings?
Dr. Cloyd: The motivation for the study was that, anecdotally, we had noticed that several of our patients who had been discharged on a weekend required readmission for potentially preventable reasons. We wanted to investigate whether the data supported the idea that weekend discharge was associated with a higher risk of hospital readmission.
MedicalResearch.com Interview with:
Michaela Dinan, Ph.D.
Duke Clinical Research Institute and Duke Cancer Institute
Department of Medicine
Duke University School of Medicine
Durham, North Carolina
Medical Research: What is the background for this study? What are the main findings?
Response: I think it will be critical to further explore the implications of Oncotype DX breast cancer assay (ODX testing) in women with breast cancer. The ODX test helps predict which cancers will be more aggressive as well as guide recommendations as to which patients would most likely benefit from chemotherapy. I think we should look to see what impact this test is really having on the use of chemotherapy and its associated costs and outcomes for real-world breast cancer patients.
MedicalResearch.com Interview with:
Eyal Leshem, MD
Division of Viral Diseases,
US Centers for Disease Control and Prevention,
Atlanta, Georgia
Medical Research: What is the background for this study? What are the main findings?
Response: Routine vaccination of US children to protect against rotavirus began in 2006. The purpose of this study was to examine the effect of implementation of rotavirus vaccine on gastroenteritis and rotavirus hospitalizations of children younger than 5 years old.
The main finding from this study is that hospitalizations for diarrhea in U.S. children younger than 5 years old decreased dramatically during 2008 to 2012 following implementation of routine rotavirus vaccination in 2006. Additionally, seasonal peaks of hospitalizations for rotavirus illness were considerably reduced after the vaccine was implemented compared to years prior to rotavirus vaccination.
By 2012, rates of rotavirus hospitalization declined by approximately 90% across all settings and age groups. Factors such as increasing vaccine coverage as well as herd immunity resulting in less transmission of rotavirus may be responsible for this large decrease.
MedicalResearch.com Interview with: Kelvin TSOI BSc, PhD Research Associate Professor, Stanley Ho Big Data Decision Analytics Research Centre Associate Professor (by Courtesy), School of Public Health and Primary Care Faculty of Medicine The Chinese University of Hong Kong MedicalResearch: What is the background for this study? What are the main findings? Dr. Tsoi: Dementia is a...
MedicalResearch.com Interview with:
Emmanuel S. Antonarakis, M.B.B.CH
Department of Urology and Oncology
Johns Hopkins University School of Medicine
Baltimore, Maryland
Medical Research: What is the background for this study? What are the main findings?
Dr. Antonarakis: In a previous publication, we reported that detection of the androgen receptor splice variant 7 (AR-V7; an abnormal version of the androgen receptor) in circulating tumor cells from patients with advanced prostate cancer was associated with resistance to hormonal therapies such as abiraterone and enzalutamide. Here, we aimed to explore the role of AR-V7 in the context of chemotherapy treatment. We showed that detection of AR-V7 was not associated with resistance to the chemotherapy drugs docetaxel or cabazitaxel, and that AR-V7-positive patients could still derive benefit from these chemotherapies.
MedicalResearch.com Interview with:
Marie Marklund, DDS senior lecturer
Department of Odontology, Faculty of Medicine
Umeå University
Sweden
MedicalResearch: What is the background for this study? What are the main findings?
Response: Snoring and obstructive sleep apnea are common in the population and these disorders continuously increase because of the ongoing obesity epidemic in many countries. Today, 34% of men and 17% of women in the US suffer from obstructive sleep apnea of all severities. Symptoms include daytime sleepiness, poor sleep quality, headache, insomnia and restless legs. In the longer term, a more severe sleep apnea is associated with serious consequences, such as hypertension, stroke, cancer, traffic accidents and early death.
Continuous positive airway pressure is a highly effective treatment for sleep apnea patients. Adherence problems, for instance from nasal stuffiness and claustrophobia reduces its effectiveness. An oral appliance holds the lower jaw forwards during sleep in order to reduce snoring and sleep apneas. This therapy has primarily been suggested for snorers and patients with mild and moderate sleep apnea. No previous placebo-controlled study has, however, evaluated this specific group of patients. Results from more severe sleep apnea patients have shown a good effect on sleep apneas. The effect of oral appliances on daytime symptoms is unclear. Symptomatic improvement is an important outcome for milder sleep apnea patients.
The primary aims of the present study were to study the effects on daytime sleepiness and quality of life of a custom-made, adjustable oral appliance in patients with daytime sleepiness and snoring or mild to moderate sleep apnea, i.e. the primary target group for this type of therapy. Secondary aims included the effects on sleep apnea, snoring and various other symptoms of sleep disordered breathing such as headaches and restless legs. We found that oral appliance therapy was effective in reducing sleep apneas, snoring and symptoms of restless legs. The apnea-hypopnea index was normal (<5) in 49% of patients using the active appliance and in 11% using placebo, with a numbers needed to treat of three. Daytime sleepiness and quality of life did not differ during active treatment and the placebo intervention. The patients experienced reduced headaches with active treatment, but the results did not differ from placebo. It was concluded, that a custom-made, adjustable oral appliance reduces obstructive sleep apneas, snoring and possibly restless legs. The efficacy on daytime sleepiness and quality of life was weak and did not differ from placebo in this group of patients.
MedicalResearch.com Interview with:
Julia E. Richards, Ph.D.
Harold F. Falls Professor of Ophthalmology and Visual Sciences
Professor of Epidemiology
Director, Glaucoma Research Center
The University of Michigan
Medical Research: What is the background for this study?
Response: We have a special interest in how the developmental processes of aging increase the risk of late onset diseases. We wondered whether drugs that target known aging pathways might be able to reduce risk of late onset disease. In the aging field, an emerging area of interest has been the category of drugs called caloric restriction mimetic (CRM) drugs, which have been found to extend life span and to reduce risk or delay onset of some late-onset diseases. These caloric restriction mimetic drugs target a set of pathways that have come to be seen as playing roles in longevity. One of these caloric restriction mimetic drugs, metformin, happens to also be one of the most common drugs used in the treatment of type 2 diabetes.
Glaucoma is a leading cause of blindness worldwide and classical open-angle glaucoma shows onset in late middle age or late age, so we hypothesized that a caloric restriction mimetic drug might be able to reduce the risk of open-angle glaucoma. We used data from a large health services database to compare the rate at which open-angle glaucoma developed in individuals with diabetes mellitus who used metformin versus those who did not use metformin. We predicted that metformin would be associated with reduced risk of open-angle glaucoma.
Medical Research: What are the main findings?
Response: We found that use of metformin was associated with reduced risk of open-angle glaucoma. A 2 gram per day dose of the CRM drug metformin for two years was associated with a 20.8% reduction in risk of developing open-angle glaucoma. When we looked at the highest quartile of drug prescribed (>1,100 grams over a two year period) we found a 25% reduction in risk relative to those taking no metformin. This risk reduction is seen even when we account for glycemic control in the form of glycated hemoglobin, and use of other diabetes drugs was not associated with reduced risk of open-angle glaucoma. A possible explanation for our findings might be that the mechanism of risk reduction is taking place by CRM drug mechanisms that target aging pathways rather than through glycemic control of diabetes.
In the long run, the approaches to late onset diseases in general will become much more powerful if we can use parallel approaches that simultaneously target both the aging processes going on and the disease-specific pathways going on. In the literature we see caloric restriction mimetic drugs metformin, rapamycin and resveratrol all being explored for their ability to target points in aging pathways in ways that can impact the risk of a variety of late-onset diseases, so it will be important for those interested in the risk factors affecting late onset diseases to pay attention to how caloric restriction mimetic drugs might be altering risk for those late onset diseases.
MedicalResearch.com Interview with:
Timothy Michael Pawlik, M.D., M.P.H., Ph.D.
Chief, Division of Surgical Oncology
Professor of Surgery
John Hopkins
Medical Research: What is the background for this study?
Dr. Pawlik: The prognosis of patients operated on for colorectal liver metastasis (CRLM) is currently defined by various “traditional” clinicopathologic factors. However the insight that they provide is incomplete. KRAS is the most common oncogene of the RAS family and is reported in up to 30 to 40% of patients with colorectal liver metastasis. As a result, KRAS mutational status recently attracted a lot of attention as a potential prognostic factor in colorectal liver metastasis. However, overall mutant KRAS status (compared to wild type) correlated with worse survival only in some studies.
We hypothesized that the specific KRAS activating mutations (codon 12 and codon 13) confer different biologic behaviors to the tumor and in turn, account for different (if any) prognostic values. The different proportions of each KRAS specific mutation could determine whether the overall mutational status would be associated with worse survival. In our view, the different proportions of specific mutations in various cohorts could account for the variability of the outcomes in different studies.
Medical Research: What are the main findings?
Dr. Pawlik: Our results showed that only codon 12 KRAS mutations conferred a worse prognosis whereas codon 13 ones did not. Furthermore, we examined the different point mutations that constitute codon 12 mutations and we found that among G12A, G12D, G12V, G12C and G12S KRAS point mutations, only G12V and G12S were independent prognostic factors of worse survival. That confirmed our hypothesis that only some of the point mutations do have a significant prognostic role and that the relative incidence of those mutations could determine if overall KRAS mutational status would be associated with worse survival in a certain cohort.
MedicalResearch.com Interview with: Elliot B Tapper, M.D. Clinical Fellow in Medicine (EXT) Beth Israel Deaconess Medical Center Boston MA 02215 Medical Research: What is the background for this study? What are the main findings? Dr. Tapper: Elevation of liver enzymes is a common problem, affecting 7.9% of Americans. It is usually related to typical conditions...
MedicalResearch.com Interview with:
Wiliam C. Huang, MD FACS
Associate Professor of Urology
Division of Urologic Oncology
NYU Langone Medical Center/Perlmutter Cancer Center
Medical Research: What is the background for this study? What are the main findings?
Dr. Huang: The presentation of kidney cancers has dramatically evolved over the past two decades with most kidney cancers being incidentally diagnosed at an early stage. We have begun to recognize that at this small size (< 4 cm), the tumors are frequently indolent in nature and some are completely benign. Consequently, the management options for these small cancers have expanded and evolved. Whereas the entire removal of the kidney was the treatment of choice in the past, alternative options including removal or ablation of the tumor-bearing portion of the kidney has become increasingly utilized. Similar to other early stage cancers, watchful waiting or observation is also becoming a reasonable treatment option.
We used the most recent SEER-Medicare Data (2001 – 2009) to evaluate the management trends and outcomes of small kidney cancers in the new millennium. We believe that this is an important study as it provides important and practical findings, which are useful to both clinical researches as well as practicing physicians.