BACKGROUND There are many reports of adolescents with periodic episodes each followed by complete remission within 2 weeks, but the nosology and long-term prognosis of such cases have not been elucidated.
METHOD A prospective follow-up study on 11 cases (nine girls and two boys) meeting predetermined criteria is reported.
RESULTS The first several episodes were found to meet ICD-10 symptomatic criteria for recurrent depressive disorder in all cases, and except for two cases, showed psychotic features. The episodes were linked to one phase of the menstrual cycle in only two of six girls with regular menses. There were no recurrences while on lithium in eight of nine cases. Of eight patients followed up 5-14 years after the first onset, three had been well, three had become bipolar and two were still suffering from brief depressive episodes.
CONCLUSIONS Recurrent brief episodes in adolescence tend to show a near-monthly rhythm and psychotic features. Most of them appear to the manifestations of affective illness and may be treated and prevented as such.