Genetic Variants for LDL Cholesterol and Risks for Alzheimer Disease and Parkinson Disease

The effect of low LDL cholesterol on the risk for neurodegenerative disease has not been well-established. Inhibition of plasma proprotein convertase subtilisin-kexin type 9 (PCSK9) and of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase leads to lower LDL cholesterol levels. Researchers examined whether PCSK9, HMG-CoA receptor (HMGCR), and other genetic variations are associated with risk for Alzheimer disease (AD), vascular dementia, any dementia, and Parkinson disease. They determined the associations of (1) baseline LDL scores with risk for these diseases, (2) genetic variants of PCSK9 and HMGCR with LDL cholesterol levels, (3) LDL cholesterol–lowering PCSK9 and HMGCR alleles with disease risk, and (4) whether all genetic varia…