Statins may exert a dose-dependent, neuroprotective quality against Parkinson’s disease in patients with diabetes, results from a large populations study indicate.
The study, published in Annals of Neurology, suggests that statins may serve a greater purpose beyond control of lipids and cardiovascular events.
In order to examine this possible association, Kun-Der Lin, MD, of Kaohsiung Medical University and Chung-Ho Memorial Hospital in Taiwan, and colleagues randomly sampled 1 million patients from a national health insurance database from 2001-2008. The researchers identified 50,432 patients with diabetes, of which half were statin users. Statin users were then classified by dose-duration-day>28 per year.
Dr Lin and colleagues found that incidence of Parkinson’s disease was lower in statin users than non-users, with an HR of 0.65(0.57-0.74) in females and 0.60(0.51-0.69) in males. After regression analysis, Parkinson’s incidence was found to be greater in patients with older age and a history of stroke events.
The researchers then stratified the statins into 4 groups: simvastatin, lovastatin, atorvastatin, and others (pravastatin and fluvastatin). After adjustment for age, income, hypertension, hyperlipidemia, stroke, ischemic heart disease, Deyo-Charlson Comorbidity Index (CCI) scores, and use of other lipid-lowering drugs, all statin groups except for lovastatin were found to be associated with a dose-dependent protective effect for Parkinson’s disease in both sexes.
“Because evidence regarding the relationship between statin use and PD is equivocal, the protective mechanism of statins may extend beyond the lipid lowering effects,” the authors wrote. “Previous animal studies have shown that chronic simvastatin treatment may affect dopamine levels in the prefrontal cortex and striatum of the brain, and changes in dopamine levels are associated with PD development.”