Mood variability in adolescents: a study of depressed, nondepressed and comorbid patients.

In a study to examine the variability of mood in psychiatrically disturbed adolescents, 30 inpatients aged 13-17 reported on current depressive symptoms three times a day for seven consecutive days, using a set of visual analog scales (the Adolescent Mood Scale: AMS) to record DSM-IIIR and other depressive symptoms. Ten of the patients had no depressive diagnosis; 11 had both a depressive and an 'externalizing' diagnosis (mainly conduct disorders and substance abuse disorders), and nine had depressive diagnoses but no externalizing disorder. Variability was defined in terms of (1) range of AMS scores; (2) amount of change from one test point to the next; (3) rhythmicity, measured by the autocorrelation function across 21 test points. All three groups had high levels of depressive symptoms throughout the week. On all measures of severity of depression, the depressed girls were more depressed than the depressed boys, irrespective of comorbidity. Measures of variability, however, showed no effect of sex, but comorbid patients were more likely to have a wide range of mood scores, and reported a 45% greater amount of mood change. Only five subjects had a significant lag1 autocorrelation function, and there was no indication of diurnal rhythmicity. Implications for research and diagnosis are discussed.