INVERSE ASSOCIATION OF SERUM-CHOLESTEROL WITH PLASMA-INSULIN IN THE ELDERLY - CROSS-SECTIONAL AND PROSPECTIVE ANALYSES

Cross-sectional studies have suggested that high plasma insulin is ass ociated with relatively low levels of low density lipoprotein (LDL)-ch olesterol. The present study was aimed at re-testing this association in a 70-year-old age cohort (N=1023), and testing whether it could be caused by excessive mortality of hyperinsulinemic subjects with high L DL-cholesterol. A reverse U-shaped association between LDL-cholesterol and fasting plasma insulin was confirmed. LDL-cholesterol, HDL-choles terol and total cholesterol were lowest in the highest insulin quarter . These associations remained after adjustment for diabetes, obesity a nd general health status. The combination of high LDL-cholesterol (>4. 25 mmol/L, 75th percentile) and high insulin (>10 IU/L, 50th percentil e) was not associated with excess 5-year mortality in this age cohort. Nor was it associated with excess mortality in four other elderly age cohorts (N=1188), in which similar associations of cholesterol and in sulin have been demonstrated. Thus, the inverse association of LDL-cho lesterol with fasting insulin in the elderly is not caused by selectiv e over mortality. (Aging Clin. Exp. Res. 10: 137-140, 1998) (C)1998, E ditrice Kurtis.