Depressive disorders in childhood. IV. A longitudinal study of comorbidity with and risk for anxiety disorders.

As part of a longitudinal nosologic study of major depressive disorder (MDD), dysthymic disorder (DD), and adjustment disorder with depressed mood (ADDM) in a school-age cohort, we examined the prevalence and clinical consequences of comorbid anxiety disorders. We also estimated the risk of a first anxiety disorder and examined its predictors. Of 104 cases, 41% had anxiety disorders in conjunction with their index depression, which was more likely with MDD and DD than with ADDM. The age-corrected risk of a first anxiety disorder was 0.47 up to age 18 years. Separation-anxiety disorder was the most frequent diagnosis of anxiety, followed by overanxious disorder of childhood. Among the MDD cases with comorbidity, the anxiety disorder preceded the depression about two thirds of the time and often persisted after the depression remitted. The effect of comorbid anxiety disorder on the length of index MDD depended on the presence of other clinical features, but it did not seem to affect the risk of subsequent MDD or the course of DD or ADDM. Concurrent maternal psychopathology and poor physical health increased the risk of anxiety disorder in the children, but a history of prior separation from parental figures did not seem to have an effect.