Environmental Risk Factors for LD
The findings from two unrelated research studies support a growing body of evidence that suggests some risk factors for learning disabilities and ADHD are environmental, and therefore potentially preventable. In one study, gestational diabetes was associated with higher incidence of ADHD, and in another study secondhand smoke was linked to ADHD and LD.
Gestational Diabetes
In the gestational diabetes study, reported in the most recent issue of Archives of Pediatrics and Adolescent Medicine, children born to women who developed diabetes during their pregnancy, and/or lived in low-income households, were at greater risk for subsequently being diagnosed with ADHD.
As a result of growing obesity rates, the number of women who experience gestational diabetes mellitus (GDM, or diabetes during pregnancy,) has increased steadily over the past 20 years, especially among low-income individuals. In an effort to understand the impact on children, a research team led by Yoko Nomura, MD, Ph.D of Queens College surveyed parents of children born to mothers with and without GDM.
The team found that children born to GDM mothers from low-income households were 14 times more likely to be diagnosed with ADHD than other children. As the researchers concluded:
This study demonstrates that children of mothers with GDM raised in lower SES [socioeconomic status] households are at far greater risk for developing ADHD and showing signs of suboptimal neurocognitive and behavioral development. Since ADHD is a disorder with high heritability, efforts to prevent exposure to environmental risks through patient education may help to reduce the nongenetic modifiable risk for ADHD and other developmental problems.
Secondhand Smoke
Medical News Today (MNT) recently reported the results of another study that found, “Children exposed to secondhand smoke in the home appear to be at 50% higher risk of neurobehavioural disorders such as ADHD/ADD and learning disabilities compared to unexposed children…”
In this study, researchers at the Harvard School of Public Health analyzed survey data of more than 55,000 American children under age 12. The findings, as summarized by MNT include:
- 6% of these children under 12 were exposed to secondhand smoke in the home: this corresponds to 4.8 million across the whole of the US.
- The weighted prevalence of learning disabilities among these children was 8.2%.
- For ADHD/ADD the prevalence was 5.9% and for behavioral and conduct disorders this was 3.6%. Children exposed to secondhand smoke at home had a 50% higher chance of having two or more childhood behavioral disorders compared with unexposed children.
- Boys appeared to be at significantly higher risk than girls.
- Older children, especially aged between 9 and 11, and those in the poorest households had the highest risk.
- Expressed in absolute terms (that is looking at the equivalent across the whole of the US), if children had not been exposed to secondhand smoke in the home, and if the relationship between such exposure and risk were to be causal, then these figures would show it may be possible to prevent 274,000 children from developing neurobehavioral disorders.
Both studies suggest the important role that modifiable environmental factors (factors that can be changed) play in the development of LD and ADHD, pointing to possible prevention pathways.
January 24th, 2012 at 10:57 pm
As a special education teacher in high poverty school, I find this article very interesting! I will be sharing this information with my colleagues and our parent group. Our children are our country’s greatest resource – we need to continue to find ways to keep them healthy and support their learning. They ARE the future, after all.
February 3rd, 2012 at 3:07 pm
Here’s the thing, we know from the Centers for Disease Control’s (CDC) surveys, the single most common risk factor for Attention Deficit Hyperactivity Disorder is poverty! So, as in all good research, this research raises questions for further study…
1) I’m not certain it is documented, but certainly research suggests, obesity is a symptom of ADHD. So, the first study becomes somewhat of a chicken and egg proposition! The implication to me seems to be perhaps we should, even as adults never be too afraid to look into the possibilities of treating our ADHD and the positive outcomes for the health of ourselves and our children.
2) Similarly, I am certain there is research to support more individuals who live in poverty smoke. So, again, is it the poverty or the smoke? This study would be more relevant if there was some data to suggest the factoring of the numbers of students with smoke in the home by income. In other words, are students students with smoke in the home all 50% more likely to be affected by neurobiological disorders – regardless of income?
And don’t even get me started on the numbers reflecting the likelihood of those affected with ADHD also becoming smokers – un/diagnosed! Is this a reflection of their income level or their need for stimulation un/prescribed? I’m not sure if it is 80% of all students affected with ADHD are also affected with LD or visa versa. Particularly for those of us in the teaching profession, does it even matter?
It is duly noted those affected with ADHD are chronically misunderstood and often held at the bottom of their professions (if they should make it to a profession) because of the socioeconomic factors of their upbringing and the sometimes mentally, physcically, and socially crippling pervasiveness of their disorder.
I would refer the special teacher working in the high poverty school to look into research presented to me in a study of the book “Boys and Girls Learn Differently”. This research, obviously peppered with hormones, found students living in low income areas – prone to violent crime – as much as 50% more likely to be diagnosed ADHD as their same age counterparts because of their exposure to violence and the subsequently wash of degenerative hormones over the brain. Sort of a PTSD for the homefront if you will!
Thanks for the food for thought!