β2‐adrenoreceptor medications and risk of Parkinson disease

We examined whether confounding by clinical indication for these medications, that is, tremor and smoking‐r elated pulmonary conditions, explained these associations.MethodsIn a large, population ‐based case–control study of United States Medicare beneficiaries in 2009 with diagnosis codes, procedure codes, and prescription data (48,295 incident PD cases, 52,324 controls), we examined the risk of PD in relation to use of selected β antagonists (propranolol, carvedilol, metoprolol), the β2 agonist salbutamol, and other medications used for the same clinical indications (primidone, inhaled corticosteroids). We adjusted for demographics, smoking, and overall use of medical care. We then examined the effect of also adjusting for clinical indication and applying medication exposure la gging.ResultsPropranolol appeared to increase PD risk (odds ratio [OR]  = 3.62, 95% confidence interval [CI] = 3.31–3.96). When we adjusted for tremor or abnormal involuntary movement prior to the PD diagnosis/reference date and lagged propranolol exposure, the association was 0.97 (95% CI = 0.80–1.18). Primidone, also used for tremor, was similarly sen sitive to this adjustment and lagging. β Antagonists not indicated for tremor appeared to reduce PD risk (carvedilol: OR = 0.77, 95% CI = 0.73–0.81; metoprolol: OR = 0.94, 95% CI = 0.91–0.97) and were insensitive to adjustment for indications and lagging. Neither salbutamol nor inhaled corticosteroids were ...
Source: Annals of Neurology - Category: Neurology Authors: Tags: Research Article Source Type: research