Working Memory Problems Can Persist Into Adulthood in Children with ADHD

Dr. Graham Murray PhD University Lecturer Department of Psychiatry Addenbrooke's Hospital Cambridge UKMedicalResearch.com Interview with:
Dr. Graham Murray PhD
University Lecturer
Department of Psychiatry
Addenbrooke’s Hospital
Cambridge UK

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

Dr. Murray: There is debate about the extent to which ADHD persists into adulthood, with estimates suggesting that between 10-50% of children still have ADHD in adulthood. Diagnosis (whether in childhood or adulthood) is currently reliant on meeting symptom checklists (such as the American Psychiatric Association’s Diagnostic and Statistical Manual), and a current diagnosis is often the prerequisite to access health care from psychiatric services. We decided to follow up a sample of 49 teens who all had a confirmed diagnosis of ADHD at age 16. We also followed a control group made up of comparison healthy volunteers from the same social, ethnic and geographical background.

When we used the symptom checklist criteria of persistence, only 10% of patients still met ADHD diagnostic criteria in adulthood. However, there is more to ADHD than this. When it comes to adult brain structure and function, it didn’t make any difference whether symptom checklists were still met or not. On reaching adulthood, the adolescent ADHD group show reduced brain volume in the caudate nucleus – a key brain region that supports a host of cognitive functions, including working memory function. When we assessed working memory ability, we noted persistent problems in the adolescent ADHD group, with a third of the adolescent ADHD sample failing the memory test. The poor memory scores seemed to relate to a lack of responsiveness in the activity of the caudate nucleus that we could detect using functional MRI scans. In the control group, when the memory questions became more difficult, the caudate nucleus became more active, and this appeared to help the control group perform well; in the adolescent ADHD group, the caudate nucleus kept the same level of activity throughout the test. It was as if, for the controls, when the test got harder, the caudate nucleus went up a gear in its activity, and this is likely to have helped solve the memory problems. But for the adolescence ADHD group, the caudate couldn’t go up a gear when the test became harder, and this likely resulted in poorer performance.  Continue reading

CDC Discusses Best Practices and Resources For Childhood ADHD

Susanna N. Visser, DrPH Epidemiologist at the National Center on Birth Defects and Developmental Disabilities CDCMedicalResearch.com Interview with:
Susanna N. Visser, DrPH

Epidemiologist at the National Center on Birth Defects and Developmental Disabilities
CDC

 

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

Dr. Visser: Attention-Deficit/Hyperactivity Disorder, or ADHD is one of the most common chronic conditions of childhood. It often persists into adulthood.   When children diagnosed with ADHD receive proper treatment, they have the best chance of thriving at home, doing well at school, and making and keeping friends.

In 2011, the American Academy of Pediatrics (AAP) updated their guidelines for ADHD treatment. The new guidelines give this advice to healthcare providers, psychologists, educators, and parents of children with ADHD:

  • For preschoolers ages 4-5 with ADHD, use behavioral therapy before medication.
  • For older children and teens with ADHD, use behavioral therapy along with medication.

In order to learn more about ADHD treatment patterns, CDC researchers looked at data from a national sample of children with special health care needs, ages 4-17 years, collected in 2009-10 just before the release of the 2011 guidelines.

We found that most children with ADHD received either medication treatment or behavioral therapy. However, we also found that many children were not receiving treatment in the way it was outlined in the 2011 best practice guidelines.

  • Less than 1 in 3 children with ADHD received both medication treatment and behavioral therapy, the preferred treatment approach for children ages 6 and older.
  • Only half of preschoolers (4-5 years of age) with ADHD received behavioral therapy, which is now the recommended first-line treatment for this group.
  • About half of preschoolers with ADHD were taking medication for ADHD, and about 1 in 4 were treated only with medication.

Continue reading

ADHD Linked To Increased Risk of Accidents and Premature Death

Dr Søren Dalsgaard National Centre for Register-based Research Aarhus University DenmarkMedicalResearch.com Interview with:
Dr Søren Dalsgaard
National Centre for Register-based Research
Aarhus University Denmark

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

Response: This is the first large-scale prospective study of all-cause-mortality in people with ADHD. The nationwide Danish registers offer unique research possibilities. We followed a cohort of almost 2 million individuals prospectively, from birth and for up to 32 years. Using a personal identifier we were able to merge data from a number of different registers at the level of each individual and within the cohort we identified and followed more than 32,000 individuals with ADHD and the rest of the cohort were controls

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

Response: In this study we document that children, adolescents and adults with ADHD are at risk of premature death, compared to people without ADHD, in fact, ADHD doubles the risk. Still, it is important to notice that although ADHD increases the relative risk of premature death, the absolute risk is very low, i.e. very few died during follow-up, in fact only 107 out of the more than 32,000 individuals with ADHD we followed.

The most common cause of death in individuals with ADHD was accidents.

Those diagnosed with ADHD in adulthood had higher mortality than those diagnosed in childhood and adolescence. In addition, co-existing problems such as conduct disorder or substance use disorder in individuals with ADHD further increases mortality. However, even those with more pure DHD had an increased mortality, compared to those without ADHD. Finally, we also examined gender-differences in mortality and found that girls and women with ADHD had a higher mortality than boys or men with ADHD.

Our results adds to the overwhelming existing evidence that ADHD is a true disorder and should not be taken lightly. ADHD has huge impacts on everyday life and people with ADHD and their families deserves that this is acknowledged.

Although the risk of premature death is twice that of individuals without ADHD, it is important to remember reassure patients with ADHD and their families, that there was very few absolute number of deaths among individuals with ADHD.

Citation:

Mortality in children, adolescents, and adults with attention deficit hyperactivity disorder: a nationwide cohort study
Published online: February 25, 2015
Søren Dalsgaard, Søren Dinesen Øtergaard, James F Leckman, Preben Bo Mortensen, Marianne Giørtz Pedersen
The Lancet

DOI: http://dx.doi.org/10.1016/S0140-6736(14)61684-6

Dr Søren Dalsgaard, National Centre for Register-based Research, & Aarhus University Denmark (2015). ADHD Linked To Increased Risk of Accidents and Premature Death 

Pesticide Exposure May Impact Development Of ADHD

MedicalResearch.com Interview with:
Jason R. Richardson MS,PhD DABT Associate Professor
Department of Environmental and Occupational Medicine
Robert Wood Johnson Medical School and
Resident Member
Environmental and Occupational Health Sciences Institute
Piscataway, NJ

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

Dr. Richardson:  Although ADHD is often though of as a genetic disorder, no single gene can explain more than a fraction of the cases. This suggests that environmental factors are likely to interact with genetic susceptibility to increase risk for ADHD. Our study reports that exposure of pregnant mice to relatively low levels of a commonly used pesticide reproduces the behavioral effects of ADHD in their offspring. Because the study was in animals, we wanted to see if there was any association in humans. Using data from the Centers for Disease Control and Prevention we found that children and adolescents with elevated levels of metabolites of these pesticides in their urine, which indicates exposure, were more than twice as likely to be diagnosed with ADHD.

Continue reading

ADHD and Conduct Disorders Linked to Early Tobacco and Alcohol Use

William Brinkman, MD, MEd, MSc Associate Professor of Pediatrics Director, Research Section, Division of General & Community Pediatrics Research Director, Cincinnati Pediatric Research Group James M. Anderson Center for Health Systems Excellence Cincinnati Children’s Hospital Medical CenterMedicalResearch.com Interview with:
William Brinkman, MD, MEd, MSc

Associate Professor of Pediatrics
Director, Research Section, Division of General & Community Pediatrics
Research Director, Cincinnati Pediatric Research Group
James M. Anderson Center for Health Systems Excellence
Cincinnati Children’s Hospital Medical Center

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

Dr. Brinkman: Early onset of substance use is a significant public health concern as those who use substances before the mid-teen years are more likely to develop dependence than those who start later. The association of attention-deficit/hyperactivity disorder (ADHD) and conduct disorder (CD) with tobacco and alcohol use has not been assessed in a young adolescent sample representative of the U.S. population.

Continue reading

ADHD Genetic Risks Also Predict Milder Attention and Language Difficulties

MedicalResearch.com Interview with:
Joanna Martin, PhD student
MRC Centre for Neuropsychiatric Genetics and Genomics
Institute of Psychological Medicine and Clinical Neurosciences,
Cardiff University School of Medicine, Cardiff

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

Response: In this study, we found that genetic risks which are collectively important for ADHD diagnosis also predict higher levels of traits of hyperactivity/impulsiveness, inattention and  pragmatic language difficulties in childhood in the general population.
Continue reading

Study Finds No Increase In Suicide Events With ADHD Drug Treatments

Dr. Henrik Larsson PhD Associate Professor Department of Medical Epidemiology and Biostatistics Karolinska Institute Stockholm, SwedenMedicalResearch.com Interview with:
Dr. Henrik Larsson PhD
Associate Professor
Department of Medical Epidemiology and Biostatistics
Karolinska Institute
Stockholm, Sweden

MedicalResearch: What are the main findings of the study?

Dr. Larrson: We found no evidence for an overall increased rate of suicide related events associated with the use of stimulant or non-stimulant drug treatment for ADHD. If anything, the results pointed to a potential protective effect of drugs for ADHD on suicidal behaviour, particularly for stimulant drugs.
Continue reading

Single Gene Mutation May Predispose to ADHD

Dr. Anders Nykjaer MD, PhD Mayo Clinic in Florida and Aarhus University in DenmarkMedicalResearch.com Interview with:
Dr. Anders Nykjaer MD, PhD
Mayo Clinic in Florida and
Aarhus University in Denmark

MedicalResearch: What are the main findings of the study?

Dr. Nykjaer: It is well known that ADHD is a complex condition caused by a number of factors including genetic and environment. However, approximately 75% etiology is considered to be genetic and a large body of investigations suggests that it is multiple genes each with a moderate effect that is responsible for conferring susceptibility to ADHD. We have here found one single gene the dysfunction of which is sufficient to trigger the disease.  The gene encodes a receptor, SorCS2, which ensures correct wiring our reward system during embryonic development. Malfunction of the receptor causes ADHD-like symptoms in mice. It is well accepted that ADHD predisposes to psychiatric disorders and genetic reports have linked variations in the SorCS2 gene with schizophrenia. Studies are currently ongoing to evaluate if mutations disrupting the function of SorCS2 may also result in schizophrenia. If this is the case we have come closer to an explanation for the link between ADHD and psychiatric disorders. In the future when prenatal genetic screening becomes established, non-sense mutations in the SorCS2 gene can be used to predict that the child will develop ADHD with 100% certainty.   Continue reading

Prenatal Exposure To Tobacco Increases Risk of ADHD Symptoms

MedicalResearch.com Interview with:
Nathalie E. Holz, MA
Department of Child and Adolescent Psychiatry and Psychotherapy
Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany

MedicalResearch: What are the main findings of the study?

Dr. Holz: Using data from a prospective community sample followed since birth, we investigated the impact of prenatal maternal smoking on lifetime Attention-Deficit/ Hyperactivity Disorder (ADHD) symptoms and on brain structure and inhibitory control assessed with Magnetic Resonance Imaging in the adult offspring. Those who were prenatally exposed to tobacco not only exhibited more ADHD symptoms, but also showed decreased activity in the inhibitory control network encompassing the inferior frontal gyrus as well as the anterior cingulate cortex. Activity in these regions was inversely related to lifetime ADHD symptoms and novelty seeking, respectively. In addition volume in the inferior frontal gyrus was decreased in these participants.
Continue reading

ADHD and Acetaminophen During Pregnancy

Jørn Olsen, M.D., Ph.D.  Professor Institute of Public Health, Department of Epidemiology UCLA Aarhus University Aarhus,DenmarkMedicalResearch.com Interview with:
Jørn Olsen, M.D., Ph.D. 
Professor Institute of Public Health, Department of Epidemiology UCLA
Aarhus University
Aarhus,Denmark

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

Dr. Olsen: Acetaminophen (paracetamol) is drug being used by many, including pregnant women. In our data about half of all pregnant women in 1995 to 2002 had used the drug all least once during their pregnancy. The drug has shown hormonal disruptor properties in animal studies.

We found that women who used this drug during pregnancy gave birth to children who 5 – 10 years later slightly more often had behavioral problems or were treated for ADHD. The risk was highest for those who took the medication late in pregnancy and/or had taken the drug several times. The increased risk was about 10-30%.
Continue reading

ADHD: Using MRI to Measure Brain Iron

Dr. Vitria Adisetiyo, Ph.D. Postdoctoral Research Fellow Medical University of South Carolina Center for Biomedical Imaging Charleston, SC 29425MedicalResearch.com Interview with:
Dr. Vitria Adisetiyo, Ph.D.
Postdoctoral Research Fellow
Medical University of South Carolina
Center for Biomedical Imaging Charleston, SC 29425


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

Dr. Adisetiyo:  Using a non-invasive MRI method called magnetic field correlation imaging, we detected significantly reduced striatal and thalamic brain iron in medication-naive children and adolescents with ADHD compared to age-, gender- and IQ-matched typically developing controls. ADHD patients who had a history of psychostimulant medication treatment (e.g. Ritalin, Aderrall) had brain iron levels comparable to controls, suggesting brain iron may normalize with psychostimulants. Blood iron measures did not differ between patients and controls.

Continue reading

ADHD: Environmental Risk Factors

MedicalResearch.com Interview with: Professor Desiree Silva MB BS, FRACP, MPH Consultant Paediatrician Suite 210 Specialist Centre, Joondalup Health Campus 60 Shenton Avenue, Joondalup WA 6027MedicalResearch.com Interview with:
Professor Desiree Silva MB BS, FRACP, MPH
Consultant Paediatrician
Suite 210 Specialist Centre, Joondalup Health Campus
60 Shenton Avenue, Joondalup WA 6027


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

Prof. Silva: Our study is one of the largest population based studies of 12,991 children with ADHD. We found that smoking in pregnancy, maternal urinary infections, preeclampsia, being induced and threatened pre-term labour increases the risk of ADHD with little gender differences.  Prematurity also increased the risk of ADHD including babies born late preterm and early term marginally increased the risk of ADHD.
Continue reading

How Does Stimulant Medication for ADHD in Children Affect Later Substance Use?

Kathryn L. Humphreys, M.A., Ed.M.  Clinical Psychology Doctoral Student UCLA Department of Psychology 1285 Franz Hall, Box 951563 Los Angeles, CA 90095MedicalResearch.com eInterview with Kathryn L. Humphreys, M.A., Ed.M.

Clinical Psychology Doctoral Student
UCLA Department of Psychology
1285 Franz Hall, Box 951563
Los Angeles, CA 90095

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

Response: Our primary question was to answer whether the use of stimulant medication in the treatment of ADHD was associated with increased or decreased risk for a variety of substance use (ever tried) and substance use disorder (abuse or dependence) outcomes (alcohol, cocaine, marijuana, nicotine, and non-specific drug use).

Prior research from individual studies of children have provided mixed evidence (i.e., some found medication increased later risk, some found medication decreased risk, and still others found no difference in risk). We examined available longitudinal studies (i.e., medication treatment preceded measurement of substance outcome) together using meta-analysis, a technique that aggregates findings from a number of studies, in order to examine this question in a much larger sample of individuals.

Our main finding was that children with ADHD who received medication treatment did not differ in risk for lifetime substance use or abuse or dependence compared to those children with ADHD who did not receive medication treatment.
Continue reading