Genetic and Lifestyle Factors Play Role in Autism Diagnosis

The diagnosis of autism and autism spectrum disorder (ASD) has increased significantly in recent years. Some of this increase may well be due to a lowering of the criteria for diagnosing ASD. Even so today with about one in every 54 baby boys and one in 88 children now being diagnosed with ASD, there seems little doubt this illness is increasing. Children with ASD suffer some degree of problems with language and verbal communication and other deficits?in social skills. If one identical twin has ASD the odds are high his/her sibling will also. Since this is true to a far greater degree for identical twins than it is for fraternal twins it leaves little doubt that genetic factors play a significant role in who gets ASD. However, genetic factors cannot explain the rather dramatic increase in ASD over the last 20 years. There is also data linking older fathers and particularly older mothers with a greater chance of having a child with?ASD. However, the age of parents has increased only modestly in the last two decades, so this is unlikely to explain much of the increase in ASD. For a while there was heightened concern that childhood vaccines (especially MMP) might be playing a role in promoting ASD but this theory is now largely discredited because of the exposed flawed ?research? by Dr. Andrew Wakefield. So what could be contributing to the apparent rise in ASD? A study by Paula Krakowiak at UC Davis and published in the May issue of Pediatrics examined over 1000 children 2-5y of age. She found that those born to obese mothers were about 60% more likely to have a child who developed autism and more than twice as likely to have a child born with some other type of developmental problems. In this study having an obese mother, especially one who had diabetes and/or elevated blood pressure were the variables most closely correlated?with an increased risk of a child developing ASD. Some researchers have suggested that insulin resistance and the accompanying metabolic abnormalities may be adversely impacting brain development.Bottom Line: It is certainly too early to conclude that being overweight and having insulin resistance promotes ASD. However, there is already more than sufficient reasons to encourage would be mothers to eat a healthier diet, be more active, and shed excess body fat, preferably before becoming pregnant. If it turns out that a healthier diet also cuts their risk of giving birth to a child with developmental problems including autism then this would be yet another potential motivator that could be used to encourage women of child bearing age to eat healthier and be more active before and after becoming pregnant.By James J. Kenney, PhD, FACN.