Impact of change in high-density lipoprotein cholesterol from baseline on risk for major cardiovascular events.

INTRODUCTION: Low concentration of high-density lipoprotein cholesterol (HDL-C) has increasingly been recognized as a strong and independent predictor of cardiovascular risk. The aim of this study was to determine the association between change in HDL-C concentration from baseline and risk of a major cardiovascular event in a commercially insured population cohort with suboptimal HDL-C and low-density lipoprotein cholesterol (LDL-C) concentrations at baseline.
METHODS: A retrospective longitudinal survival analysis was conducted using claims data from a large, commercial US health plan. To be included, patients had to be > or =50 years of age on the index date (laboratory test date between January 1, 2000 and December 31, 2003 on which both their LDL-C and HDL-C were not at goal), be continuously enrolled for a minimum of 6 months prior to and 12 months after the index date, and had to have at least one other laboratory panel result within 1 year prior to the cardiovascular event or study disenrollment. Cox proportional hazards analysis was conducted to assess the association between change in HDL-C concentrations and risk of a major cardiovascular event (defined as a > or =1-day hospitalization for a cardiovascular disease [CVD] diagnosis or an invasive cardiovascular procedure) within 5 years of the index date, after adjusting for covariates.
RESULTS: A 0.026 mmol/L (1 mg/dL) increase in HDL-C from baseline was associated with a statistically significant 1.9% decreased risk of a major cardiovascular event (P<0.0001; hazard ratio: 0.981; 95% CI: 0.974, 0.989), after adjustment for covariates.
CONCLUSION: Our finding of an inverse association between change in HDL-C concentrations and risk of a major cardiovascular event confirms previously reported results. Increasing HDL-C concentrations may serve as an effective measure for preventing future cardiovascular events.