ADHD takes a toll well into adulthood

"Only 37.5 percent of the children we contacted as adults were free of these really worrisome outcomes," says lead investigator William Barbaresi, M.D., of Boston Children's Hospital, who started the study when he was at Mayo. "That's a sobering statistic that speaks to the need to greatly improve the long-term treatment of children with ADHD and provide a mechanism for treating them as adults."

The study is unique because it followed a large group of ADHD patients from childhood to adulthood, says Slavica Katusic, M.D., an epidemiologist and Mayo Clinic's lead researcher on the study.

ADHD is the most common neuro-developmental disorder of childhood, affecting about 7 percent of all children and three times as many boys as girls. Most prior follow-up studies of ADHD have been small and focused on the severe end of the spectrum -- such as boys referred to pediatric psychiatric treatment facilities -- rather than a cross-section of the ADHD population.

The study followed all children in Rochester who were born between 1976 and 1982, were still in Rochester at age 5 and whose families allowed access to their medical records. That amounted to 5,718 children, including 367 diagnosed with ADHD. Of this group, 232 participated in the follow-up study. About three-quarters received ADHD treatment as children.

At follow-up, the researchers found:

*29 percent of children with ADHD still had ADHD as adults.

*57 percent of children with ADHD had at least one other psychiatric disorder as adults, as compared with 35 percent of those studied who didn't have childhood ADHD. The most common were substance abuse/dependence, antisocial personality disorder, hypomanic episodes, generalized anxiety and major depression.

*Of the children who still had ADHD as adults, 81 percent had at least one other psychiatric disorder, as compared with 47 percent of those who no longer had ADHD and 35 percent of those without childhood ADHD.

*Seven of the 367 children with ADHD (1.9 percent) had died by the time the study began, three of them from suicide. Of the 4,946 children without ADHD whose outcomes could be ascertained, 37 children had died, five by suicide.

*Ten adults who had childhood ADHD (2.7 percent) were incarcerated when the study started.

"We suffer from the misconception that ADHD is just an annoying childhood disorder that's overtreated," Dr. Barbaresi says. "This couldn't be further from the truth. We need to have a chronic disease approach to ADHD as we do for diabetes. The system of care has to be designed for the long haul."

Dr. Barbaresi thinks the study findings may underestimate the bad outcomes of childhood ADHD. Most of those studied were white and middle class, with good educations and access to health care.

"One can argue that this is potentially a best-case scenario," Dr. Barbaresi says. "Outcomes could be worse in socioeconomically challenged populations."

He advises parents of children with ADHD to ensure that their children are in high-quality treatment -- and remain in treatment as they enter adolescence. Children also should be assessed for learning disabilities and monitored for conditions associated with ADHD, including substance use, depression and anxiety.

The study was supported by Public Health Service research grants #s MH076111, HD29745 and AG034676. Pilot work for a portion of the project was funded by an investigator-initiated grant from McNeil Consumer and Specialty Pharmaceuticals.