Serum total cholesterol concentration and 10-year mortality in an 85-year-old population

Little is known about the association between total cholesterol (TC) and all-cause mortality in the elderly (especially the very elderly). Here we examined the association between TC and all-cause mortality in 207 very elderly (85-year-old) participants. In 2003, we performed a baseline laboratory blood examination, and blood pressure (BP) and body mass index (BMI) measurements, and lifestyle questionnaires were completed by the participants. The participants were followed for the subsequent 10 years. As of 2013, of the 207 participants in 2003, 70 participants had survived, 120 individuals had died, and 17 were lost to follow up. The TC values were divided into high-TC (≥209 mg/dL), intermediate-TC (176-208 mg/dL), and low-TC (≤175 mg/dL) categories. With the Kaplan-Meier method, we found that both the high-TC and intermediate-TC participants survived longer than the low-TC participants. The men with high TC survived longer than those with low TC, but no corresponding difference was found for the women. A multivariate Cox proportional hazards regression model, with adjustment for gender, smoking, alcohol intake, history of stroke or heart disease, serum albumin concentration, BMI, and systolic BP, revealed that the total mortality in the low-TC group was 1.7-fold higher than that in the high-TC group. Mortality, adjusted for the same factors, decreased 0.9% with each 1 mg/dL increase in the serum TC concentration and decreased 0.8% with each 1 mg/dL increase in the serum (low-density lipoprotein) LDL-cholesterol (LDL-C) concentration. Our results indicate an association between lower serum TC concentrations and increased all-cause mortality in a community-dwelling, very elderly population. Mortality decreased with the increases in both TC and LDL-C concentrations, after adjustment for various confounding factors. These findings suggest that low TC and low LDL-C may be independent predictors of high mortality in the very elderly.