The role of pramipexole in the treatment of patients with depression and Parkinson's disease: A meta-analysis of randomized controlled trials.

Objective: The aim of this report was to evaluate the clinical efficacy and safety of pramipexole therapy for patients with depression and Parkinson's disease (dPD), in order to confer a reference for clinical practice.

Methods: Randomized controlled trials (RCTs) of pramipexole for dPD published up to June 2020 were retrieved. Standardised mean difference (SMD), risk ratio (RR), and 95 % confidence interval (CI) were calculated. The outcomes included efficacy, Hamilton depression rating scale (HAMD) score, unified Parkinson's disease rating scale (UPDRS) scores, self-rating depression scale (SDS) score, self-rating anxiety scale (SAS) score or adverse events.

Results: Eighteen RCTs with 1789 participants were included. Clinical efficacy in pramipexole treatment group was significantly better than control group (RR 1.26, 95 % CI 1.20-1.33, P < 0.00001). Compared with control group, the pooled effects of pramipexole therapy on depression were (SMD -1.90, 95 % CI -2.58 to -1.23, P < 0.00001) for HAMD score, (SMD -3.94, 95 % CI -4.73 to -3.15, P < 0.00001) for SDS score, pramipexole therapy also decreased SAS score markedly (P < 0.0001). Compared with control group, the pooled effects of pramipexole on motor UPDRS score and activities of daily living UPDRS score were statistically significant (P < 0.01). Furthermore, pramipexole therapy didn't increase the number of any adverse events in dPD patients (RR 0.72, 95 % CI 0.37-1.41, P = 0.34).

Conclusions: Pramipexole therapy can alleviate depressive symptoms and motor dysfunction in dPD patients, and there were no more side effects associated with drug intervention. These findings should be further validated by high-quality and well-designed RCTs.