Prospective long-term follow-up of patients with pervasive developmental disorders.

We conducted a 12-year prospective study of children with pervasive developmental disorders from North Dakota. In a prospective longitudinal follow-up study, of 59 patients, we found 52 patients with pervasive developmental disorders (88%). Ten (17%) declined to participate. We collected data on 42 (71%) of the original cohort. Of the 42 subjects, 1 died (1.7%). The other 41 were followed up for 492 person-years. Severity scores for the Diagnostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) declined 20% and for DSM-IV 23%. Global Assessment of Functioning improved 19%, and the average number of comorbidities decreased 45%. Thirty-seven percent of patients improved in all four measures, whereas only 5% improved in only one measure. Pervasive developmental disorders are developmental disorders with a long-term course of limited improvement for most patients. Male subjects demonstrated substantially more variability in improvement but, overall, demonstrated more improvement than female subjects.