Time to recurrence after recovery from major depressive episodes and its predictors.
BACKGROUND
Depression is a remitting but recurring disease. However, there is a paucity of prospectively recorded data on the course of depression after recovery.


METHODS
A multi-centre prospective serial follow-up study of an inception cohort of hitherto untreated unipolar major depression (N = 95) for 6 years. We report the time to recurrence after recovery from the index depressive episode and their predictors.


RESULTS
The cumulative probability of remaining well without subthreshold symptoms was 57% (95% CI, 46 to 68%) at 1 year, 47% (95% CI, 36 to 58%) at 2 years and 35% (95% CI, 23 to 47%) at 5 years. The same without full relapse was 79% (95% CI, 70 to 88%) at 1 year, 70% (95% CI, 60 to 80%) at 2 years and 58% (95% CI, 46 to 70%) at 5 years. The median duration of well-interval from the end of the index episode to the beginning of the subthreshold episode was 19-0 months (95% CI, 2-4 to 35-7), and that to the end of the full episode was over 6 years. Residual symptoms at time of recovery predicted earlier recurrence.


CONCLUSIONS
The median length of the well-interval was much longer than previously reported in studies employing similar definitions but dealing with a more severe spectrum of patients. However, the sobering fact remains that less than half of the patients can expect to remain virtually symptom-free for 2 years or more after recovery from the depressive episode.
Kanai
T
T
Department of Psychiatry, Nagoya City University Medical School, Nagoya, Japan.
Takeuchi
H
H
Furukawa
T A
TA
Yoshimura
R
R
Imaizumi
T
T
Kitamura
T
T
Takahashi
K
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000517:prevention & control* / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D055502:Secondary Prevention; D016896:Treatment Outcome