Objective: To determine and compare rates of homotypic continuity of childhood- and adolescent-onset depression into adulthood.
Method: This was a naturalistic, prospective cohort study of children and adolescents receiving psychiatric care at all community mental health centers in Madrid, Spain, from January 1986 to December 2007. Data were obtained from a regional registry wherein all psychiatric visits to public mental health centers are recorded. Patients received their first diagnosis of an ICD-10 F32 or F33 depressive disorder between 6 and 17 years of age and were at least 20 years old at the time of their last visit. Subjects whose first diagnosis was in childhood (aged 6-12 years: depressed-child group) and subjects whose first diagnosis was in adolescence (aged 13-17 years: depressed-adolescent group) were compared in terms of demographic characteristics, psychiatric comorbidity, and rates of homotypic continuity in adulthood.
Results: Five hundred twenty-eight patients with depressive disorders met inclusion criteria. The depressed-adolescent group had a higher proportion of girls (60.3%) compared to the depressed-child group, but did not differ on other demographic or clinical variables. Most subjects who later received treatment in adult mental health facilities (n = 243; 57.2%; 95% CI, 50.9-57.2) continued to be diagnosed with a depressive disorder. High rates of anxiety disorders, bipolar disorder, personality disorders, and psychotic disorders in adulthood were observed among subjects from both groups. The absence of psychiatric comorbidity prior to age 18 years was associated with homotypic continuity of depressive disorder into adulthood.
Conclusions: Subjects with adolescent-onset depression and subjects without comorbid psychiatric disorders in youth appear to have a higher level of homotypic continuity into adulthood. Both children and adolescents with depressive disorders are at risk for other psychiatric disorders in adulthood.