Author Response: Association of Statins With Cerebral Atherosclerosis and Incident Parkinsonism in Older Adults.

Abstract

We thank Dr. Keller for the comment about our study.1 Accumulating evidence suggests that factors that contribute to parkinsonism in adults without Parkinson disease (PD) are likely to contribute to and exacerbate parkinsonism in adults with a clinical diagnosis of PD.2,3 This study focuses on older adults without a clinical diagnosis of PD and suggests that statin treatment is associated with reduced incident parkinsonism during the past decade of life through its association with brain atherosclerosis, but not due to PD or other neurodegenerative pathologies. However, most of the decedents in our study had mixed-brain pathologies. Although 69 (6.6%) showed PD pathology, more than one-third showed 1 or more cerebrovascular disease pathologies.1 A prior study by our group has shown that older adults in community-based studies with a clinical diagnosis of PD also accumulate mixed-brain pathologies that commonly include cardiovascular disease pathologies in addition to PD pathology.4 Thus, our data suggest that to determine the efficacy of statins in reducing the severity of parkinsonian signs in PD, future trials should focus on a subgroup of adults with PD that also have evidence of intracranial atherosclerosis.