Management of Depression in Parkinson's Disease: A Systematic Review

Background Depression is a frequent psychiatric condition in Parkinson's disease (PD). The treatment of depression has been examined in several randomized controlled trials and meta‐analyses, but no clear guidelines are available. Methods We carried out a systematic review of pharmacological and non‐pharmacological treatments for depression in patients with PD using the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines. We searched main medical databases up to December 12, 2016, and included randomized controlled trials, patient‐control studies, and case series with data on treatment modality, outcome measures, and side effects. Results Selective serotonergic reuptake inhibitors and tricyclic antidepressants may have efficacy for the treatment of depression in patients with PD, although the evidence is not strong. The antidepressant efficacy of dopamine agonists is still controversial, and initial results were positive for pramipexole but not for rotigotine. Cognitive‐behavioral therapy showed promising results in two recent randomized controlled trials, but further evidence is required. Studies using repetitive transcranial magnetic stimulation produced conflicting results, and the efficacy results for this treatment have been inconsistent. On the other hand, electroconclusive therapy produced strong positive results in patients with severe depression, but no randomized controlled trials are available. Conclusion Selective serotonergic reuptake inhibitors and cognitive‐behavioral therapy are currently first‐line treatments for depression in patients with PD, although the evidence is still weak. The heterogeneity among contributory factors for depression in PD should be considered for the most effective treatment of depression in this condition.