MHA4 SSRI Antidepressant Use Patterns and their Relation to Clinical Global Impressions Scores: A Naturalistic Study

Abstract

Previous studies of antidepressants in clinical practice have established a link between initial antidepressant selection and patterns of antidepressant use and health care expenditures. However, there has been far less research to date demonstrating a link between the patterns of antidepressant use and patients' clinical outcomes using data from actual clinical practice. OBJECTIVE: The purpose of this study using data from a clinical practice setting was to test whether the pattern of antidepressant use was correlated with patients' treatment response as measured by the score on the Clinical Global Impressions-Improvement scale. DATA AND METHODS: A dataset of patients who initiated therapy on one the most common selective serotonin reuptake inhibitors (SSRLs) fluoxetine, fluvoxamine, paroxetine, or sertaline in a general practitioner setting in Spain was used. A Cox proportional hazard analysis was used to predict the liklihood of treatment response based upon the pattern of initial antidepressant use, while controlling for the influence of other baseline characteristics. RESULTS: After controlling for other observed baseline characteristics including initial disease severity, patients who remained on their initial antidepressant therapy for at least two months with no switching, augmentation, or upward dose titration were 63.2% more likely (p < 0.05) than patients who had an adjustment to therapy to exprience a treatment response. CONCLUSION: The pattern of antidepressant use is an important determinant of treatment response among patients initiating therapy on the newer antidepressants in clinical practice.