Prevalence of Autism Spectrum Disorders Lower in Black and Hispanic Children

MedicalResearch.com Interview with:

Maureen Durkin, PhD, DrPH Professor and Interim Chair Department of Population Health Sciences University of Wisconsin School of Medicine and Public Health Madison, WI

Prof. Durkin

Maureen Durkin, PhD, DrPH
Professor and Interim Chair
Department of Population Health Sciences
University of Wisconsin School of Medicine and Public Health
Madison, WI 

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

Response: Previous studies of the prevalence of autism spectrum disorder (ASD) among children in the U.S. have found two consistent patterns.  One is a higher prevalence among white non-Hispanic children than among black non-Hispanic or Hispanic children.  The other is a positive socioeconomic gradient, meaning that ASD prevalence in the U.S. is found to increase with increasing income and other indicators of socioeconomic status.

One of the findings of this new study is that the racial and ethnic differences in autism spectrum disorder prevalence are not explained by socioeconomic factors, because even after adjusting for socioeconomic factors, ASD prevalence was found to be significantly lower in black and Hispanic children than in white non-Hispanic children.  Another finding is that the gap in ASD prevalence between children of high and low socioeconomic status did not change over time between 2002 and 2010, though the overall prevalence of ASD more than doubled during this period.

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Autism Spectrum Disorder Found To Be Highly Heritable

MedicalResearch.com Interview with:

Sven Sandin, PhD Assistant Professor Department of Psychiatry Icahn School of Medicine at Mount Sinai New York, NY 10029

D. Sandin

Sven Sandin, PhD Assistant Professor
Department of Psychiatry
Icahn School of Medicine at Mount Sinai
New York, NY 10029 

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

Response: In 2014, we estimated the heritability of autism to be approximately 50%. Motivating us then was the lack of studies in autism heritability using population based and the findings from a twin-study in California finding the heritability to be substantially lower than the 80-90% estimated in previous studies. Since then continued efforts working with the questions on heritability and environmental factors for autism we found differences between different methods and different samples. When we went back to our previous data we found the heritability of autism to be higher than previously estimated. We found that our previous result was due to a methodological artifact where the adjustment for differences in follow-up used in that manuscript underestimated the heritability. Using methods used in other heritability studies the heritability is now estimated to 84%. Importantly, as previously concluded, there is no support for any ‘shared environmental factors’ in the etiology of autism, e.g. environmental factors shared between two siblings.

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Folic Acid May Reduce Risk of Autism Associated With Pesticide Exposure During Pregnancy

MedicalResearch.com Interview with:

Rebecca J. Schmidt, M.S., Ph.D.  Assistant Professor, Public Health Sciences UC Davis California

Dr. Schmidt

Rebecca J. Schmidt, M.S., Ph.D. 
Assistant Professor, Public Health Sciences
UC Davis California

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

Response: Maternal folic acid taken near conception has been linked to reduced risk for autism in the child in previous studies.

Separate studies show that exposure to pesticides during pregnancy is associated with increased risk for autism.

Animal studies demonstrate that folic acid and other B-vitamins can attenuate effects of certain environmental contaminants, including pesticides.

This case-control study examined combined maternal folic acid and pesticide exposures in relation to autism in the child.

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Stress May Aggravate GI Symptoms in Autism Spectrum Disorder

MedicalResearch.com Interview with:

David Q. Beversdor MD Center for Translational Neuroscience University Hospital University of Missouri Health System Columbia, MO 65212

Dr. David Beversdor

David Q. Beversdor MD
Center for Translational Neuroscience
University Hospital
University of Missouri Health System
Columbia, MO 65212

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

Response: Altered stress reactivity, alterations in cytokines and a high incidence of gastrointestinal disturbances have all been observed in autism spectrum disorder (ASD). We wished to examine the interactions between these factors.

What we found was that patients with greater stress reactivity, as indicated by cortisol response in the testing environment, had greater symptomatology involving the lower gastrointestinal tract, which was predominated by constipation.

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