Low LDL cholesterol, PCSK9 and HMGCR genetic variation, and risk of Alzheimer’s disease and Parkinson’s disease: Mendelian randomisation study

Two errors occurred in the print abstract of this paper (BMJ 2017;357:j1648, doi:10.1136/bmj.j1648). In both instances the level of low lipoprotein cholesterol was omitted. The study answers and limitations section should have stated that “Genetic evidence suggested that low low density lipoprotein cholesterol levels may lead to a low risk of Alzheimer’s dementia.” Similarly, the what this study adds section should have stated that “The findings suggest that low low density lipoprotein cholesterol has no harmful causal effect on risk of Alzheimer’s dementia, vascular dementia, any dementia, and Parkinson’s disease.”