OBJECTIVE:

This study was undertaken to assess whether the diagnosis of attention deficit hyperactivity disorder (ADHD) is retained from childhood into adulthood.

METHOD:

A search of the literature yielded nine prospective studies in which cohorts of children with the disorder were formed and then reexamined 4-16 years later to determine the level of retained ADHD. The resulting data were subjected to nonlinear regression analysis to ascertain the relationship with chronological age.

RESULTS:

The data followed an exponential decline over time to a high degree of accuracy.

CONCLUSIONS:

The rate of ADHD in a given age group appears to decline by 50% approximately every 5 years. If a prevalence of ADHD in childhood of 4% is assumed and the exponential decline extrapolated, the estimated rate of adult ADHD ranges from about 0.8% at age 20 to 0.05% at age 40.