Antidepressive treatments for Parkinson's disease: A systematic review and meta-analysis

Context: Depression affects 50-70% of patients with Parkinson's disease resulting in significant comorbidity, executive dysfunction, and poorer quality of life. Divergent results from studies of different treatments preclude definite treatment recommendations. Objective: To perform a systematic review and meta-analysis of published randomized controlled trials (RCTS) evaluating the efficacy of pharmacologic and behavioral interventions, and repetitive transcranial magnetic stimulation (rTMS) for depression among patients with idiopathic Parkinson's disease. Data sources: Trial registers and the following databases were searched: PubMed, CINAHL, EMBASE, and PsycInfo. Bibliographies of relevant articles were cross-referenced. Study selection and data extraction: RCTs comparing pharmacologic, behavioral, or rTMS with a placebo/other drugs or methods with no restrictions on participant age, gender, and duration or setting of treatment were included. Eligibility assessment was performed independently. Identified records were sequentially screened according to eligibility criteria. Differences in mean depression score and 95% confidence intervals were calculated. Results: A total of 893 idiopathic Parkinson's disease patients with clinical depression across 20 RCTs were included. The overall standard mean difference for all pharmacologic interventions was 0.30 (95% CI-0.00, 0.61, p=0.054). On stratification, there was a distinct difference in effect between antidepressants (SMD of 0.54, 95%CI 0.24, 0.83, p=0.000) and non-antidepressants (SMD of-0.29, 95% CI-0.86, 0.29, p=0.328). Behavioral interventions demonstrated significant efficacy with an effect size of 0.87 (95% CI 0.41, 1.33, p=0.000). Conclusions: This meta-analysis demonstrates that pharmacologic treatment with antidepressant medications, specifically the selective serotonin reuptake inhibitors (SSRIs), and behavioral interventions (CBT) significantly improved depression among Parkinson's disease patients.