Noncontinuous use of antidepressant in adults with major depressive disorders – a retrospective cohort study

BACKGROUND Noncontinuous antidepressant use is frequently observed in clinical practice despite the standard recommendation of at least 6-9 months of continuous treatment. The problem may be more serious in Chinese populations where stigmatization is common. This retrospective cohort study investigated the rate of noncontinuous antidepressant use and subsequent rate of relapse and recurrence in psychiatric Chinese outpatients by examining the prescription records, electronic medical records, and written medical records. Factors associated with noncontinuous antidepressant use were also identified. METHODS We reviewed the medical records of 189 patients newly dispensed with an antidepressant in the psychiatric outpatient clinic during year 2006 and 2007. Primary outcome was the rate of noncontinuous antidepressant use within 6 months of therapy. Secondary outcomes included the factors associated with noncontinuous antidepressant use and the rate of subsequent depression relapse and recurrence within 1 year of starting treatment. RESULTS Among the 189 subjects included in this study, 46% were noncontinuous users of the newly prescribed antidepressant therapy. The noncontinuous users were found to have an eightfold increase (OR: 8.42, 95% CI: 3.30-21.47) in the risks of relapse/recurrence depressive episodes within 1 year after treatment initiation. Younger age (P = 0.008), female, (P = 0.029), residency in public housing estate (P = 0.029), experiencing side effects (P = 0.024), infrequent follow-ups (P = 0.006), and earlier onset of diagnosis (P = 0.034) were factors significantly associated with noncontinuous antidepressant use. CONCLUSIONS Noncontinuous antidepressant use is common in the local Chinese depressive patients and associated with a high rate of relapse and recurrence. Collaborative multidisciplinary approaches that target patient education and enhancement of follow-up adherence are needed.