Discontinuation of antidepressant therapy among patients with major depressive disorder

Abstract

Objective: Patients with major depressive disorder (MDD) often discontinue antidepressant therapy pre- maturely risking relapse, despite United Kingdom (UK) guidelines recommending therapy for up to at least six months after remission. More information is needed on the patterns of antidepressant discontinuation in UK primary care. Objectives of the study were to assess the patterns, incidence and predictors of therapy discontinuation among MDD patients initiating treatment with selective serotonin reuptake inhibitors (SSRIs). Methods: This was a retrospective cohort study using general practices registered with the General Practice Research Database (GPRD). 15,274 patients with MDD receiving a first ever prescription (index) for an SSRI between 2006-2008 were identified in GPRD. Discontinuation (including temporary gaps) and cessation of antidepressant therapy were examined over follow-up. Predictors of incidence of discontinuation in the six months after index were assessed. Results: Incidence of discontinuation of antidepressant therapy over follow-up was 80.05 per 100 person years (95% CI 78.94 - 81.17). At six months after index 42% of patients had discontinued and 33% had ceased therapy altogether. Lower discontinuation of index SSRI therapy in the first six months after initiation was associated with higher age, higher body mass index (BMI), and comorbid irritable bowel syndrome. Higher discontinuation was associated with paroxetine or fluoxetine at index, and a more recent index calendar year. Conclusions: There is a significant risk of discontinuation of antidepressant therapy in the 6 months after initiation of treatment for MDD. This finding requires awareness by the general practitioner (GP) to ensure implementation of optimal treatment regimens, and minimization of therapy non-compliance among MDD patients.