Abstract 1423: Statin Therapy Does Not Reduce the Increased Cardiovascular Risk Associated With Low Levels of High-Density Lipoprotein Cholesterol: Evidence From Randomized Controlled Trials
Background: Though statins reduce cardiovascular disease (CVD) risk, rates of CVD events in statin-treated patients remain unacceptably high. Whether the contribution of high-density lipoprotein cholesterol (HDL-C) to CVD risk in statin-treated patients differs from that in comparable non-statin treated controls is unknown. Therefore, we sought to determine whether statin therapy alters the relationship between HDL-C levels and CVD risk.
Methods: A MEDLINE search identified statin RCTs with ≥1,000 years of follow-up. Weighted meta-regressions (inverse of variance) evaluated the association of HDL-C with the risk of myocardial infarction (MI), in statin-treated cohorts and non-statin controls.
Results: A total of 20 eligible statin RCTs were identified (with 543,210 person-years of follow-up and 7,838 MIs). In both statin-treated cohorts and non-statin treated controls, there was a significant inverse association between HDL-C and the risk of MI (p=0.003 and p=0.004, respectively; FIGURE⇓). After adjusting for on-treatment LDL-C and age, this relationship persisted such that every 10 mg/dL decrement in HDL-C was associated with 7.6 (95% CI 3.9 –11.3) and 7.8 (95% CI 2.8 –13.0) more MIs per 1,000 person-years, in statin-treated patients and non-statin controls, respectively (P=0.45 for comparing the effect of HDL-C on MI risk in statin-treated patients versus controls). In contrast, statin treatment reduced MIs by a median of 4.4 per 1,000 person-years.
Conclusion: Baseline HDL-C levels contribute importantly to the risk of MI in statin-treated patients. These data support that low HDL-C levels contribute to the residual CVD risk observed in statin-treated patients.