Depressive symptoms impacting on health-related quality of life in early Parkinson's disease: Results from Chinese l-dopa exposed cohort

Objective: To investigate the impact of depressive symptoms on health-related quality of life (HR-QOL) in a group of patients with early Parkinson's disease (PD). Methods: A 20-item scale, the Center for Epidemiologic Studies Depression Scale (CESD) and a 36-item questionnaire, the medical outcomes study short form (SF-36) were administered as part of baseline assessment of a clinical trial in PD, enrolling 391 early-stage, l-dopa exposed PD patients in China. We used multiple regression models to examine the relationship of depressive symptoms, measured by the CESD with HR-QOL, as measured by the SF-36. The SF-36 score of the depressed patients was compared with those non-depressed, as well. Results: A total of 146 (37.3%) patients screened positive for depression. Compared with those non-depressed, depressed patients had lower scores in all dimensions of SF-36 profile (p < 0.001). Multiple regression analysis revealed that depressive symptoms, measured by CESD, increased our ability to explain the variance of SF-36 total score by 34.5%. Additionally, depressive symptom is the only variable which has the predictive value not only for total SF-36 total score, but also for each subdimension score of SF-36 profile. Conclusion: Depressive symptoms are common early in the disease, having a substantial impact on patients' HR-QOL, affecting many areas other than the obvious mental health dimension of the HR-QOL profile. Our results highlight the broad importance of treating depression in this population.