NEW YORK—A history of diabetes and elevated levels of cholesterol, especially LDL cholesterol, are associated with faster cognitive decline in patients with Alzheimer’s disease, according to a new study from Columbia University Medical Center researchers. The study, published in the March 2009 issue of Archives of Neurology, provides further evidence of the role of vascular risk factors in the onset and progression of Alzheimer’s disease.
Researchers used longitudinal data for a mean of 3.5 years (up to 10.2 years) for 156 people diagnosed with Alzheimer’s disease who were participants in the Washington Heights/Inwood Columbia Aging Project, a 10-year multi-ethnic, prospective, epidemiological study of cognitive aging and dementia in northern Manhattan.
They found that a history of diabetes and higher cholesterol levels (total cholesterol and LDL-C) was associated with faster cognitive decline. A history of heart disease and stroke was found to be associated with cognitive decline only in carriers of the apolipoprotein E e4 (APOE-e4) gene, which has been implicated in late-onset Alzheimer’s disease.
The researchers theorize that the link between vascular risk factors and faster cognitive decline in patients with Alzheimer’s disease may occur because vascular diseases may increase oxidative stress or activate inflammation in the brain, thereby triggering the production of amyloid, and/or triggering the formation of neuron tangles that are believed to be a primary cause of Alzheimer’s disease.