Affiliations: Department of Pharmacy Practice, National Institute of Pharmaceutical Education and Research, Mohali, Punjab, India
Note:  Correspondence to: Dr. Dipika Bansal, Department of Pharmacy Practice, Research block, National Institute of Pharmaceutical Education and Research, Mohali, Punjab-160062, India. E-mails: firstname.lastname@example.org; email@example.com (K. Gudala); firstname.lastname@example.org (H. Muthyala).
Abstract: Background: Results from several epidemiological studies found a potential role of cholesterol metabolism in Parkinson's disease (PD) pathogenesis. Further several studies assessed relation between dietary intake of cholesterol and risk of PD, although these studies showed varied results but give a clue of association between serum cholesterol and PD. Objective: We therefore examined the association between serum cholesterol and risk of PD. Methods: PubMed database and bibliographies of retrieved articles were searched for observational studies (published up to January 2013) investigating the relationship between serum cholesterol and PD. Pooled risk ratio (RR) was calculated using random-effects model. Subgroup, sensitivity analysis and publication bias were also done. Results: Eight relevant studies were identified, consisting of 4 each case-control and cohort studies involving a total of 246,112 subjects including 5,488 PD cases. Because of significant heterogeneity (pheterogeneity < 0.001, I2 = 70.34%) was observed, a random-effects model was chosen over a fixed-effects model. A combined analysis of 8 studies found no significant association between serum cholesterol and risk of PD (RR 0.87, 95% CI 0.67–1.13; p = 0.41). Conclusions: We observed no probable association between serum cholesterol and risk of PD.