Chronic Use of β-Blockers and the Risk of Parkinson's Disease.

Background: Most patients with Parkinson's disease exhibit intracellular accumulation of the α-synuclein protein encoded by the α-synuclein gene. It was recently shown that β-adrenoreceptor agonists downregulate this gene, decreasing the apparent risk of Parkinson's disease by up to 40%. In contrast, exposure to β-blocking drugs increases production of the α-synuclein protein.