A Potential Role for Statins in the Long-term Reduction in the Risk of Neurodegenerative Disease

Abstract

Statins reduce the progression of cerebrovascular atherosclerosis and so may reduce the risk of vascular dementia. Statins may also reduce the formation of beta-amyloid and increase the clearance of amyloid precursor protein and so reduce the risk of Alzheimer's disease (AD). A meta-analysis of 46 longitudinal observational studies of statin therapy found that in all primary and almost all secondary analyses, statin use was associated with a lower risk of incident AD and all-cause dementia. A cohort study found that statin use was associated with a lower risk of development of Parkinson's disease (PD); the benefit appeared to be mediated by a lower risk of atherosclerosis. Whereas observational studies cannot establish a causal protective role for statins against dementia and PD, given that statins are primarily indicated for the prevention of ischemic cardiovascular and cerebrovascular events, whether or not they prevent dementia and PD is not relevant to their prescription; but if they do prevent these, it’s a bonus. It should be kept in mind that even if statins do play a significant preventative role in neurodegenerative disease, as with the benefits in the prevention of cardiovascular disease, the benefits will only be observed after many years or decades of treatment, and the numbers needed to treat will be large. Expressed otherwise, the effect size is likely to be small.