Abstract 16187: The Impact of Baseline C-Reactive Protein and Coronary Artery Calcium on the Benefit Observed With Atorvastatin: A Secondary Analysis of the St. Francis Heart Study
Background: There role of biomarkers as an index of relative benefit from statin therapy is debated. Some postulate that high hsCRP signals selective benefit due to the inflammatory state; some argue that those with advanced calcified atherosclerosis may accrue less benefit from statins. The St. Francis Heart Study (SFHS) is the only RCT with baseline measurements of each risk marker.
Methods: The SFHS enrolled 1005 asymptomatic individuals with CAC score >80th percentile for age and gender in a double-blinded, placebo-controlled, randomized study of atorvastatin 20mg vs. placebo. The intervention arm also received vitamins C and E. We conducted a secondary analysis of the SFHS stratifying by baseline hsCRP and CAC. Of 1003 participants with follow-up data, 961 had baseline measurements of hsCRP. We calculated the placebo total CVD event rate, the relative risk reduction with atorvastatin, and the absolute risk reduction with atorvastatin in each biomarker subgroup as well as in 2x2 analysis based on intention-to-treat.
Results: Mean age of the trial population was 59 ± 6 years, with 74% men. Median hsCRP was 2.07 (0.97 - 4.35) and median Agatston CAC score was 371 (183 - 659). Approximately half (49%) had hsCRP ≥2 mg/L, while 46% had CAC >400. LDL-C was reduced by 43% in the atorvastatin arm of the trial. The placebo event rate, relative risk reduction, and absolute risk reduction with the intervention are shown in the figure. Although subgroup analysis was limited by sample size, in general participants with lower hsCRP and higher CAC >400 received the greatest benefit from atorvastatin. A statistically significant 59% reduction in events (HR 0.41, 0.17 - 0.99) was observed in the hsCRP <2 / CAC >400 subgroup.
Conclusion: Although limited by sample size, our results do not support the hypothesis of selective statin benefit with high hsCRP or selective futility with advanced CAC. In the SFHS, the greatest relative and absolute benefit was observed in those with hsCRP ≤2 and CAC >400.
- © 2013 by American Heart Association, Inc.