Background: Minor depression is common in primary care and associated with increased health care costs. Many mildly depressed patients are prescribed antidepressants, although there is insufficient information on the cost-effectiveness of antidepressants for these patients. The objective of this study was to evaluate whether usual care without antidepressants is equivalent to (i.e. as effective as and as expensive as) usual care with antidepressants in patients with minor or mild-major depression.
Methods: Severity of depression was measured using the Montgomery Asberg Depression Rating Scale (MADRS) and quality-adjusted life-years (QALYs) using the EuroQol. Resource use was measured from a societal perspective using cost diaries. Bootstrapping was used to analyze the cost-effectiveness data.
Results: Equivalence could not be shown for improvement in MADRS score or QALYs gained at 52 weeks. The mean (95% CI) difference in total costs between usual care without antidepressants and usual care with antidepressants was -euro751 (-3601; 1522). Using an equivalence margin of euro500 equivalence in costs could not be shown. In the cost-effectiveness analyses equivalence also could not be shown.
Limitations: This study was underpowered for economic outcomes. Another limitation was the loss-to-follow-up.
Conclusions: Although equivalence could not be shown in the costs and cost-effectiveness analyses, 95% confidence intervals also did not show that usual care without antidepressants was vastly superior or inferior to usual care with antidepressants. Therefore, we recommend general practitioners to show restraint when prescribing antidepressants to mildly depressed patients.