Predictors of premature antidepressant discontinuation in functional gastrointestinal disorders

To identify factors responsible for premature antidepressant discontinuation that would assist in designing management strategies for patients with functional gastrointestinal disorders. Antidepressants are being used increasingly to manage patients with functional gastrointestinal disorders; poor patient adherence to treatment regimens, particularly in the period shortly after antidepressant initiation, is common and interferes with success.

Clinical records were reviewed from 172 outpatients who attended a university-based practice and who had been prescribed antidepressants to manage their functional gastrointestinal symptoms. Survival analysis methods were used to determine independent predictors of premature antidepressant discontinuation (within 6 months of initiation). Logistic regression analyses were used to see if the same predictors were responsible for side effects or poor treatment response.

Premature antidepressant discontinuation occurred in 41 (23.8%) subjects. Somatization features (state or trait) and history of depression or an anxiety disorder were the most significant predictors of premature discontinuation (p < or = .01 for each). Advancing age and female sex also were independent predictors (p < .05 for each). Somatization features and psychiatric illness were each linked to poor treatment response, whereas somatization features most consistently were associated with antidepressant side effects.

Failure to maintain treatment occurs in nearly a quarter of outpatients given antidepressants for functional gastrointestinal disorders. Somatization features and history of depression or anxiety most significantly interfered with treatment by predicting side effects, poor treatment response, and premature antidepressant discontinuation. Management algorithms should include specific strategies targeted at patients with these risk factors for poor treatment adherence.