LDL cholesterol is known as the “bad” cholesterol, because high levels are linked to heart disease, but low levels may not be good for the elderly.
A new study of older men and women shows that higher LDL cholesterol levels are associated with decreasing mortality risk in women. For both men and women, the risk of fatal heart failure decreases with higher LDL cholesterol levels.
The findings “add to the uncertainty of the role of elevated levels of LDL cholesterol as a risk factor for mortality in old people,” according to the researchers who conducted the study.
Dr. Valerie Tikhonoff of the University of Padua, Italy, and colleagues conducted a population-based study of 3120 subjects age 65 years or older, who were followed for up to 12 years.
Tikhonoff’s group reports in the Journal of the American Geriatric Society that the likelihood of dying during the follow-up period “was curvilinear ... decreasing nonlinearly with LDL cholesterol.”
The total mortality risk in relation to LDL level was J-shaped in men, meaning that the risk increased as LDL cholesterol levels fell below a mid range - although the risk increased with high levels of LDL.
Similarly, there was a J-shaped relationship to the risk of dying from cardiovascular causes for both sexes, and for the risk of having a fatal heart attack among men.
“The key finding of this study was that, in older subjects with a low use of lipid-lowering drugs representative of the general Italian population, serum LDL cholesterol behaved as a multifaceted and predominantly nonlinear predictor of cardiovascular and all-cause mortality,” Tikhonoff and colleagues conclude.
They add that results of lipid-lowering drug trials should be interpreted with caution in unselected elderly patients, because these findings contradict the usual association of high LDL cholesterol with mortality risk seen in younger patients.
SOURCE: Journal of the American Geriatric Society, December 2005.
Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD