OBJECTIVE: This study was undertaken to investigate L-type calcium channel blockers of the dihydropyridine class for association with Parkinson disease (PD), because some of these drugs traverse the blood-brain barrier, are potentially neuroprotective, and have previously been evaluated for impact on PD risk. METHODS: We identified 1,931 patients with a first-time diagnosis for PD between 2001 and 2006 as reported in the Danish national hospital/outpatient database and density matched them by birth year and sex to 9,651 controls from the population register. The index date for cases and their corresponding controls was advanced to the date of first recorded prescription for anti-Parkinson drugs, if prior to first PD diagnosis in the hospital records. Prescriptions were determined from the national pharmacy database. In our primary analyses, we excluded all calcium channel blocker prescriptions 2 years before index date/PD diagnosis. RESULTS: Employing logistic regression analysis adjusting for age, sex, diagnosis of chronic pulmonary obstructive disorder, and Charlson comorbidity score, we found that subjects prescribed dihydropyridines (excludes amlodipine) between 1995 and 2 years prior to the index date were less likely to develop PD (odds ratio, 0.73; 95% confidence interval, 0.54-0.97); this 27% risk reduction did not differ with length or intensity of use. Risk estimates were close to null for the peripherally acting drug amlodipine and for other antihypertensive medications. INTERPRETATION: Our data suggest a potential neuroprotective role for centrally acting L-type calcium channel blockers of the dihydropyridine class in PD that should be further investigated in studies that can distinguish between types of L-type channel blockers.
The objective of this study was to investigate whether statin (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor) use is associated with risk of Parkinson's disease (PD) in Denmark. We identified 1,931 patients with a first time diagnosis of PD reported in hospital or outpatient clinic records between 2001 and 2006. We density matched to these patients 9,651 population controls by birth year and sex relying on the Danish population register. For every participant, we identified pharmacy records of statin and anti-Parkinson drug prescriptions since 1995 and before index date from a prescription medication use database for all Danish residents. Whenever applicable, the index dates for cases and their corresponding controls were advanced to the date of first recorded prescription for anti-Parkinson drugs. In our primary analyses, we excluded all statin prescriptions 2-years before PD diagnosis. Employing logistic regression adjusting for age, sex, diagnosis of chronic obstructive pulmonary disease, and Charlson comorbidity, we observed none to slightly inverse associations between PD diagnosis and statin prescription drug use. Inverse associations with statin use were only observed for short-term (