Study Finds Increased Diagnosis of ADHD

Kaiser PermanenteA study that was done in Southern California found that there has been an increase of the diagnoses of ADHD in the past ten years. This study included children who lived in Southern California. It is possible that the increase is due to a better understanding of the effects of prenatal exposure to certain substances.

How many times have you heard of a study that says that the cases of ADHD are on the rise? Personally, I can think of quite a few of these types of studies that have made the news in the past couple of years. It is no longer a surprise when new studies come to the same conclusions. The interesting part is how the researchers explain the findings.

A study that was recently published in the journal JAMA Pediatrics found that the diagnoses of ADHD increased 24% in Southern California in the past ten years. The data comes from children who live in Southern California, only.

Researchers reviewed medical records for children who were treated at the Kaiser Permanente Southern California physicians group between the years 2001 and 2010. The records were anonymized. The study included 842,830 children. Researchers noted that in 2011, 2.5% of the kids who were between the ages of 5 and 11 were diagnosed with ADHD. By 2010, that number went up to 3.1%.

What is causing the increase? Researchers believe it is due to a number of factors including better awareness of ADHD. The study’s lead author is Dr. Darios Getahun from Kaiser Permanente Southern California’s Department of Research and Evaluation. He said:

These findings are particularly solid given that our study relied on clinical diagnoses of ADHD based on the criteria specified within the American Psychiatric Association’s Diagnosis and Statistical Manual of Mental Disorders and that it represents a large and ethnically diverse population that can be generalized to other populations.

Dr. Philip Landrigan is the Director of the Children’s Environmental Health Center at Mount Sinai School of Medicine. He had this to say:

Even if some of the reported increase is due to better awareness, these data seem to speak to a true increase. There’s a fairly substantial list of environmental factors that have been linked to ADHD.

According to Dr. Landrigan, some of those factors include prenatal exposure to a variety of things including maternal tobacco smoke, lead, organophosphate pesticides, and phthalates, (a plastics chemical). He notes:

I think this is a list that we can expect to continue to grow in the years ahead because we now have very sophisticated scientific tools for testing linkage between prenatal exposure and conditions like ADHD in children.

Image by Ted Eytan on FLickr