The disadvantages of attention deficit/hyperactivity disorder (ADHD) persist well into adulthood, according to a long-running cohort study.
Men in their fourth and fifth decades — diagnosed as boys with ADHD — were significantly worse off in several respects than members of a comparison group at an average age of 41, according to Rachel Klein, PhD, of New York University Langone Medical Center in New York City, and colleagues.
But the disadvantages began in adolescence and were not associated with an increased number of new disorders after the age of 20, Klein and colleagues reported online in Archives of General Psychiatry.
The findings come from analysis of 135 white men who had been diagnosed with ADHD (but did not have conduct disorder) at an average age of 8 and who have been followed for 33 years. Their educational, occupational, social, and marital outcomes have been compared over time with those of a cohort of men who did not have childhood ADHD.
At the 33-year follow-up, those in the ADHD cohort had significantly worse educational, occupational, economic, and social outcomes and were more likely to be divorced and to have been divorced.
On average, the researchers found, those in the ADHD cohort had 2.5 fewer years of schooling than those in the comparison group.
Overall, 31.1% did not finish high school, compared with 4.4% of the comparison cohort (P<0.001). In addition, 15.6% had a bachelor’s degree and 3.7% had obtained a higher degree, compared with 34.6% and 29.4%, respectively, for the comparison group (P<0.001 for both).
On the eight-point Hollingshead occupational scale – where 1 is an executive position and 8 is unemployed – those in the ADHD cohort averaged 4.7, compared with 3.0 in the comparison group (P<0.001).
While significantly fewer in the ADHD group were employed (at P=0.003), 83.7% had jobs. But there was a “striking” $40,000 disparity in median income, the researchers noted: $60,000 versus $100,000 a year.
The groups differed markedly in marital status: 9.6% of those in the ADHD group were currently divorced compared with 2.9% of the comparison cohort, and 31.1% had ever been divorced compared with 11.8% (P=0.01 and P<0.001, respectively).
They also had higher rates of ongoing ADHD (22.2% versus 5.1%, P<0.001), antisocial personality disorder (16.3% versus 0%, P<0.001), and substance use disorders other than alcohol abuse (14.1% versus 5.1%, P=0.01).
On the other hand, there was no significant difference in the rates of mood or anxiety disorders, Klein and colleagues reported.
The researchers cautioned that the study can’t be applied to women or to other ethnic and social groups.
Members of the comparison cohort who were lost to follow-up tended to have lower IQs than those who remained in the study, as well as lower socioeconomic status and more previous drug-related disorders, they noted, so that the current comparison may exaggerate “the relative dysfunctions of adults who had ADHD in childhood.”
They also cautioned that the comparison cohort does not “appear to represent an exceptionally normal group” – a quarter had conduct disorder in their youth and more than 1 in 10 had ever been incarcerated.
Nevertheless, they concluded, those in the ADHD cohort were generally worse off than their counterparts, but the “relative disadvantages in adulthood reflect persistent malfunction with earlier origin.”
Those results suggested that continued monitoring of children with ADHD — even in the absence of conduct disorder — remains important, they said.