7/01/2008 PERMALINK

Low levels of high-density lipoproteins (HDL) — the "good" cholesterol — in middle age may increase the risk of memory loss and lead to dementia later in life, researchers reported in Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association.

Observing 3,673 participants (26.8 percent women) from the Whitehall II study, researchers found that falling levels of HDL cholesterol were predictors of declining memory by age 60. Whitehall II, which began in 1985, is long-term health examination of more than 10,000 British civil servants working in London.

"Memory problems are key in the diagnosis of dementia," said Archana Singh-Manoux, Ph.D., lead author of the study and Senior Research Fellow with the French National Institute for Health and Medical Research (INSERM, France) and the University College London in England. "We found that a low level of HDL may be a risk factor for memory loss in late midlife. This suggests that low HDL cholesterol might also be a risk factor for dementia."

Researchers defined low HDL as less than 40 mg/dL and high HDL as 60 mg/dL or higher. The team compared blood-fat and memory data collected in phases 5 (1995?) and 7 (2002?) of Whitehall II, when the average ages of the study members were 55 and 61 years, respectively.