Impact of Lipid-Lowering Therapy on Mortality According to the Baseline Non-HDL Cholesterol Level: A Meta-Analysis

Introduction Previous report showed that more intensive lipid-lowering therapy was associated with less mortality when baseline LDL-C levels were > 100 mg/dL. Non-HDL-C is a better predictor of cardiovascular risk than simpler LDL-C. Aim The objective of this meta-analysis was to define the impact of lipid-lowering therapy on the reduction of total and cardiovascular mortality by different baseline levels of non-HDL-C. Methods We performed a meta-analysis including randomized, controlled clinical trials of lipid-lowering therapy, reporting mortality with a minimum of 6 months of follow-up, searching in PubMed/Medline, EMBASE and Cochrane Clinical Trials databases. The random-effects model and meta-regression were performed. Results Twenty nine trials of lipid-lowering drugs, including 233,027 patients, were considered eligible for the analyses. According to the baseline non-HDL-C level, the results on cardiovascular mortality were: (1) >= 190 mg/dL: OR 0.63 (95% CI 0.53-0.76); (2) 160-189 mg/dL: OR 0.82 (95% CI 0.75-0.89); (3) 130-159 mg/dL: OR 0.71 (95% CI 0.52-0.98); (4) < 130 mg/dL: OR 0.95 (95% CI 0.87-1.05). When evaluating mortality from any cause, the results were the following: (1) >= 190 mg/dL: OR 0.70 (95% CI 0.61-0.82); (2) 160-189 mg/dL: OR 0.91 (95% CI 0.83-0.98); (3) 130-159 mg/dL; OR 0.88 (95% CI 0.77-1.00); (4) < 130 mg/dL: OR 0.98 (95% CI 0.91-1.06). The meta-regression analysis showed a significant association between baseline non-HDL-C and mortality. Conclusions In these meta-analyses, lipid-lowering therapy was associated with reduction in the risk of all-cause and cardiovascular mortality when baseline non-HDL-C levels were above than 130 mg/dL.