Having childhood attention deficit hyperactivity disorder could lead to a life of obesity, even if ADHD symptoms disappear in adulthood, a new study shows.
The study, which followed up on 207 middle-class men who had been diagnosed with ADHD as children, found that some 33 years after their diagnosis, their body mass index was significantly higher than those without ADHD. Their propensity to become obese was twice that of adults who were never diagnosed with ADHD, according to the study published Monday in the journal Pediatrics.
Even those who did not have the disorder as an adult were heavier than those who never were diagnosed as children. But the adults whose childhood ADHD symptoms did not persist also had a similar body mass to those whose ADHD persisted into adulthood. Adjustments for socioeconomic status and lifetime mood, anxiety and substance abuse did not affect the outcomes.
The data, published Monday in the journal Pediatrics, confirm earlier work that linked higher adult weight and obesity with childhood ADHD diagnoses, and studies that ruled out any influence from anxiety and depressive disorders.
Taken together, the studies suggest aspects of ADHD may have an early influence on body weight that can persist into adulthood. Among the symptoms of ADHD that could affect weight gain is a diminished control of impulses, which could foster poor eating habits and impede planning and monitoring of eating bahavior. Deficits in executive function likewise could have a similar effect, making it difficult to follow a dietary regime.
On a neurobiological level, a measured dysfunction in certain dopamine-dependent circuits in the front of the brain have been linked to ADHD and to obesity. Limited studies and observations of obese people with ADHD hint at genetic roots to this altered dopamine pathway, according to the study.
BMI, or body mass index, was in the overweight range if it was between 25 and 30, and obese above 30. The normal range for these men would be 18.5-25.