Serum lipids and the pathogenesis of Parkinson's disease: A systematic review and meta‐analysis

The role of serum lipids in the pathogenesis of Parkinson's disease (PD) remains unclear, and the results of previous reports remain conflicting. We aimed to conduct this systematic review and meta-analysis to identify the potential relationships of blood lipids and the pathogenesis of PD.PubMed, Medline, Web of Science, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases were searched from inception to March 31, 2020, to identify potential studies with case-control or cohort study design on the relationship of serum lipids and PD. Stata 15.1 software was used for data syntheses after extraction of relevant data.A total of 12 studies with 1506 PD patients and 7330 healthy controls were included. There were no significant differences in the TC (SMD = -0.08, 95% CI [-0.45, 0.33]), LDL-C (SMD = -0.12, 95% CI [-0.46, 0.18]), and TG (SMD = -0.05, 95% CI [-0.18, 0.06]) among PD patients and healthy controls. There was significant difference (SMD = -0.32, 95% CI [-0.42, -0.25]) in the TG level among PD patients and healthy controls. Subgroup analysis by Asian and non-Asian countries indicated that geographical location was not the source of heterogeneity. And no significant publication bias was found (all P > .05).TG serum levels are significantly lower in PD patients, more studies are needed to further elucidate role of lipid in the PD development.