Researchers at NYU Langone Medical Center have discovered that men diagnosed with ADHD (Attention-Deficit/Hyperactivity Disorder) as children were twice as likely to become obese as adults. The new study titled “Obesity in Men With Childhood ADHD: A 33-Year Controlled, Prospective, Follow-up Study” appears in the May 20 online edition of Pediatrics.
The Centers for Disease Control and Prevention, estimates that ADHD is one of the most common neurobehavioral disorders. ADHD is often diagnosed in childhood and lasts into adulthood. It is estimated that five percent of the worldwide population is afflicted with ADHD. Men are more likely to be diagnosed than women.
"Few studies have focused on long-term outcomes for patients diagnosed with ADHD in childhood. In this study, we wanted to assess the health outcomes of children diagnosed with ADHD, focusing on obesity rates and Body Mass Index," said lead author Francisco Xavier Castellanos, MD of the Child Study Center at NYU Langone. "Our results found that even when you control for other factors often associated with increased obesity rates such as socioeconomic status, men diagnosed with ADHD were at a significantly higher risk to suffer from high BMI and obesity as adults."
The prospective NYU study included 207 white men diagnosed with ADHD at an average age of 8 and a comparison group of 178 men not diagnosed with childhood ADHD, who were matched for race, age, residence and social class. The average age at follow up was 41 years old. The study was designed to compare Body Mass Index (BMI) and obesity rates in grown men with and without childhood ADHD.
Results showed that, on average, men with childhood ADHD had significantly higher BMI (30.1 vs. 27.6) and obesity rates (41.1 percent vs. 21.6 percent) than men without childhood ADHD.
What is the link between childhood ADHD and obesity?
Dr. Castellanos said, "The results of the study are concerning but not surprising to those who treat patients with ADHD. Lack of impulse control and poor planning skills are symptoms often associated with the condition and can lead to poor food choices and irregular eating habits."
The study also cites neurobiological correlates such as the dysfunction of fronto-striatal dopaminergic pathways which has been implicated in ADHD as well as in obesity. These neuronal circuits underpin impulse control, executive functions, and reward sensitivity. The authors state, “Limited preliminary evidence in a few illustrative individuals with both ADHD and obesity suggests genetic alterations in chromosome regions encompassing genes possibly involved in dopaminergic regulation pathways and related systems, such as melanocortin which are also implicated in both ADHD and obesity.”
Dr. Castellanos concludes, "This study emphasizes that children diagnosed with ADHD need to be monitored for long-term risk of obesity and taught healthy eating habits as they become teenagers and adults." For some simple tips on how to make lifestyle changes that will improve your health you can check out my Psychology Today blog: Four Keys to Creating Healthy Behavior.
But there may be more to the story. . . Could there be a link between medications used to treat childhood ADHD and adult obesity? Many of the medications used to treat ADHD – like Ritalin and Adderall – have side effects that suppress appetite. The current study does not address this topic. However, I would be curious if there is a correlation between someone discontinuing use of ADHD medication as an adult and the double whammy of increased appetite and adult ADHD.
In another study released on May 16, 2013 titled “Vicious Cycle: Obesity Sustained by Changes in Brain Biochemistry” researchers from Brown University and Lifespan found that obesity impedes the production of a hormone that curbs appetite and inspires calorie burning.
The new study discovered a molecular chain reaction in the brains of obese rats that undermines their ability to suppress appetite and to increase calorie burning. The findings were published in the Journal of Biological Chemistry. The Brown University and Lifespan authors conclude, "Understanding the central control of energy-regulating neuropeptides during diet-induced obesity is important for the identification of therapeutic targets to prevent and or mitigate obesity pathology.”
Clearly, much more research needs to be done to find effective ways to combat the vicious cycle of obesity and slow this epidemic.