Use of statins and the risk of Parkinson's disease - A retrospective case-control study in the UK

Background: Case reports have related the use of HMG-CoA reductase inhibitors ('statins') to Parkinson's disease (PD). Paradoxically, however, statins may have potentially beneficial effects on neurodegenerative diseases due to their anti-inflammatory properties. Objective: To explore the risk of the development of PD in association with untreated hyperlipidaemia and with hyperlipidaemia treated with lipid-lowering drugs in the UK primary care setting. Methods: We conducted a case-control analysis using the UK-based General Practice Research Database (GPRD). Cases were incident PD cases >= 40 years of age between 1994 and 2005. One control was matched to each PD case based on age, sex, general practice and index date. Lipid-lowering drug use was assessed by exposure timing (current vs past use) and by exposure duration (1-9, 10-29 or >= 30 prescriptions) prior to the index date for both cases and controls. Odds ratios (OR) were calculated using conditional logistic regression, adjusted for body mass index, smoking and various cardiovascular, metabolic and psychiatric co-morbidities. Results: We identified 3637 cases with an incident idiopathic PD diagnosis, and the same Dumber of controls. Compared with patients without hyperlipidaemia, those with untreated hyperlipidaemia did not have an altered relative PD risk (adjusted OR 0.98, 95% CI 0.74, 1.30). The adjusted ORs for current use of 30 prescriptions for statins or fibrates compared with non-use of statins or fibrates were 1.06 (95% CI 0.75, 1.51) and 1.25 (95% CI 0.51, 3.06), respectively. Conclusions: In this observational study, the long-term use of statins or fibrates was not associated with a substantially altered relative risk of developing PD.