Health-related quality of life measured with EQ-5D in patients treated for depression in primary care

Objective: The objective of the present study was to assess the impact of depression on patients' health-related quality of life (HRQL) with the EQ-5D instrument over 6 months while on antidepressant treatment. Methods: A total of 447 patients were recruited at 56 primary care centers to this naturalistic longitudinal observational study. Patients older than 18 years with depressive symptoms, and who initiated an antidepressant therapy because of depression were included in the study. Data on patients' sociodemographics, daily activity, and quality of life (EQ-5D) were collected using questionnaires completed during outpatient general practitioner visits for a follow-up period of 6 months. Results: The mean EQ-5D utility score at baseline was 0.47 (0.44-0.49). Milder cases of depression reported a health utility of 0.60, whereas moderately and severely depressed patients reported utility values of 0.46 and 0.27, respectively (P < 0.01). At end of follow up the average utility was 0.69 (0.67-0.72), corresponding to an increase of 0.23 over 6 months (P < 0.01). Regression analyses showed that, all else equal, patients who were on sick leave were associated with 10% lower utility. Conclusions: Depression has a substantial impact on HRQL. Our results indicate that treatments for depression are associated with significant improvement in EQ-5D index score over a course of 6 months. Self-reported patient valuations are important outcomes for cost-utility analysis of new treatments for depression and the present study provides important evidence for future economic evaluations.