Efficacy of MAO-B and COMT inhibitors on quality of life in patients with Parkinson’s disease: a Bayesian network meta-analysis

Abstract

Background and Objectives – Quality of life (QoL) is a critical outcome in the management of Parkinson’s disease (PD), and is often affected more by non-motor symptoms (NMS) than motor features. While monoamine oxidase-B (MAO-B) and catechol-O-methyltransferase (COMT) inhibitors are commonly used with levodopa, their comparative impacts on QoL remains unclear. This study aimed to compare the effects of MAO-B and COMT inhibitors on global and domain-specific QoL in patients with PD using a Bayesian network meta-analysis (NMA). Methods – A comprehensive literature search was conducted using PubMed/Medline, Cochrane Library and Embase databases from the inception through April 30, 2025. Randomized controlled trials evaluating QoL using PDQ-39 or PDQ-8 in patients treated with MAO-B inhibitors (rasagiline, selegiline, safinamide) or COMT inhibitors (entacapone, opicapone, tolcapone) were included. A Bayesian NMA was performed using the “gemtc” package in R. Treatment effects were expressed as standardized mean differences (SMDs) with 95% credible intervals (CrIs). Treatment ranking was estimated using surface under the cumulative ranking curve (SUCRA) values. Results – Sixteen RCTs comprised of 3, 802 patients were included. The combination of extended-release rasagiline and pramipexole (P2B001) showed the most significant improvement in global QoL (SMD = −4.16; 95% CrI: −7.24 to −1.05), followed by rasagiline monotherapy (SMD = −2.38; 95% CrI: −4.32 to −0.42). Safinamide 100 mg significantly improved emotional well-being (SMD = −2.56; 95% CrI: −5.13 to −0.04). SUCRA rankings confirmed the superior probability of benefits for rasagiline-based interventions across multiple QoL dimensions. Conclusion – This network meta-analysis provides evidence that MAO-B inhibitors, particularly rasagiline and safinamide, may offer broader QoL benefits in patients with PD, especially in NMS such as emotional well-being. These findings support a more symptom-oriented and individualized treatment approach should be provided to patients with PD. Further well-designed head-to-head studies using standardized QoL measures and extended follow-up are needed to confirm these findings and guide clinical practice. Systematic review registration – Registered in PROSPERO (CRD420251013028): https://www.crd.york.ac.uk/PROSPERO/view/CRD420251013028