HDL Linked to Lower Risk of Alzheimer's Disease
HDL levels above 55 mg/dL associated with 60 percent lower risk of probable, possible disease
WEDNESDAY, Dec. 15 (HealthDay News) -- Older adults with high levels of high-density lipoprotein cholesterol (HDL-C) may have a lower risk of Alzheimer's disease (AD), according to research published in the December issue of the Archives of Neurology.
Christiane Reitz, M.D., Ph.D., of the Columbia University College of Physicians and Surgeons in New York City, and colleagues analyzed data from 1,130 participants, aged 65 and older, who were free of cognitive impairment at baseline.
The researchers found that, over 4,469 person-years of follow-up, 101 cases of probable or possible AD developed among participants. Levels of HDL-C greater than 55 mg/dL were associated with lower risk of either probable and possible AD or probable AD (hazard ratios, 0.4 and 0.4). Higher levels of total and non-HDL-C were also associated with lower risk after adjusting for age, sex, education, ethnic group, and APOEe4 genotype. These associations became nonsignificant after adjusting for vascular risk factors or lipid-lowering treatment.
"Dyslipidemia, and particularly low HDL-C level, is a known risk factor for cerebrovascular disease, and treatment with lipid-lowering medications can prevent stroke. Stroke is associated with higher AD risk. Stroke may interact with amyloid pathology in an additive way and lower the amyloid burden necessary to precipitate dementia. Low concentrations of HDL-C are known to be independent risk factors for carotid artery atherosclerosis, which in turn may lead to cognitive impairment through cerebral hypoperfusion, embolism, or disruption of white matter," the authors write.