Predicting relapse in major depression after successful initial pharmacological treatment.

BACKGROUND

Identifying the predictors of relapse could help to develop more individualized treatment strategies for major depression. The study aim was to explore predictors of depression relapse after remission using data from our previous multicenter randomized practical trial of patients with major depression.

METHODS

Our cohort comprised subjects with Patient Health Questionnaire (PHQ-9) scores less than 5 after antidepressant treatment for 9 weeks. Relapse was defined as a PHQ-9 score of 5 or more at week 25. We examined patient demographic and clinical characteristics at baseline (age, sex education, job status, marital status, onset age at first depressive episode, number of previous episodes, length of current episode, scores on the nine PHQ-9 criteria at week 0) and Frequency, Intensity, and Burden of Side Effects Rating Scale and PHQ-9 total scores at week 9 (residual symptoms) as potential predictors of depression relapse at week 25.

RESULTS

Of 494 patients remitted at week 9, 71 (14.4%) experienced relapse at week 25. Logistic regression analysis showed that lower PHQ-9 depressive mood score at week 0, higher suicidal ideation score at week 0, and total PHQ-9 score at week 9, and greater severity of side effects at week 9 were significant predictors. On the other hand, when relapse was defined as a PHQ-9 score of 10 or more at week 25, there were no significant predictors.

LIMITATIONS

There may be other important predictors that this study failed to identify and the findings obtained may be sensitive to the specific definition of relapse.

CONCLUSIONS

Approximately one-seventh of subjects who remitted after 2 months of acute-phase treatment experienced depression relapse within 4 months of remission. Lower depressive mood and higher suicidal ideation upon development of the current depression episode, the presence of residual symptoms, and greater severity of side effects at remission may predict subsequent depression relapse.