Adolescent psychopathology: III. The clinical consequences of comorbidity.

OBJECTIVE

To describe the clinical consequences associated with the lifetime occurrence of comorbid psychiatric disorders.

METHOD

In a community sample of 1,507 older adolescents (aged 14 through 18 years), subjects with "pure" and comorbid forms of four major psychiatric disorders (depression, anxiety, substance use, and disruptive behavior) were compared on six clinical outcome measures.

RESULTS

The impact of comorbidity was strongest for academic problems, mental health treatment utilization, and past suicide attempts; intermediate on measures of role functioning and conflict with parents; and nonsignificant on physical symptoms. The greatest incremental impact of comorbidity was on anxiety disorders; the least was on substance use disorders. Although some patterns of comorbidity were much more common in boys (e.g., substance use and disruptive behavior disorder) or in girls (e.g., depression and anxiety), the impact of specific comorbid disorders on the clinical measures was not different for females and males. The effect of comorbidity was not due to current psychopathology.

CONCLUSIONS

The significance of comorbidity differs across specific comorbid disorders and across outcome measures, with some comorbid disorders being much more detrimental, and some outcome measures much more affected, than others.