A recent article in the Journal of child Psychology and Psychiatry examined the long term course of ADHD and co-morbid diagnoses among boys and girls as they transitioned from childhood into adolescence. The vast majority of research on ADHD has been done with boys, mostly due to the sex difference in the rates of ADHD. The few studies that have included girls have shown significant differences between boys and girls in a number of domains, including the physiological correlates of the condition, cognitive function, and co-morbidities. Yet, we know little of the longitudinal progression of ADHD in girls. Specifically, it is unknown whether the course of ADHD is similar in boys and girls or whether they have similar co-morbid conditions throughout childhood and adolescence.
The authors of the Journal of Child Psychology and Psychiatry study examined participants from two independent longitudinal studies of ADHD. The first study started in the 1980s and included 140 6-to-17 year-old boys with ADHD, 206 siblings, 280 parents, and 120 non-ADHD peers. These kids were assessed for up to 10 years after the initiation of the study. The second study started in 1993 and included 140 6-to-17 year-old girls, 183 siblings, 274 parents, and 122 non-ADHD peers. These girls were followed for up to 5 years. The final sample for the study included 143 ADHD girls and 147 ADHD boys. Both groups were on average approximately 11 years old at the time of the first assessment. However boys were significantly older (mean age 19) at the time of the last followup compared to the girls (mean age 16).
