Evaluation of C-reactive protein before and on-treatment as a predictor of benefit of atorvastatin: a cohort analysis from the Anglo-Scandinavian Cardiac Outcomes Trial lipid-lowering arm

Abstract

Objectives: The aim of this study was to determine whether baseline and on-statin C-reactive protein (CRP) are independent predictors of cardiovascular (CV) outcome beyond low-density lipoprotein cholesterol (LDL-C).

Background: Use of CRP as a predictor of statin treatment remains controversial.

Methods: We investigated the relationship of baseline and on-treatment CRP with subsequent CV events in Cox models using a subset of white subjects with no history of CV disease from the UK ASCOT (Anglo-Scandinavian Cardiac Outcomes Trial).

Results: During 5.5 years of follow-up, a total of 488 subjects experienced a CV event. CV risk increased with baseline CRP (hazard ratio [HR] per 1 SD: 1.21; 95% confidence interval [CI]: 1.09 to 1.33) in an adjusted model. In ASCOT Lipid-Lowering Arm, the relative statin effect in preventing CV events did not differ according to tertiles of baseline CRP (p = 0.69). After 6 months of atorvastatin therapy, the median LDL-C and CRP were reduced by 38.7% and 25.8%, respectively. Those who achieved LDL-C below the median had a reduced CV risk (HR: 0.58; 95% CI: 0.34 to 0.97) compared with those who did not. In contrast, those who achieved a CRP level below the median did not have a reduced risk of CV events (HR: 0.95; 95% CI: 0.59 to 1.55). Among those who achieved LDL-C below the median, there was no difference in CV risk whether they also achieved a CRP level below (HR: 0.55; 95% CI: 0.30 to 1.02) or above the median (HR: 0.56; 95% CI: 0.30 to 1.03).

Conclusions: In these primary prevention patients, although baseline CRP independently predicted CV event risk, the achieved CRP level on while statin therapy did not predict CV events, either alone or in combination with LDL-C.

Keywords: BMI; C-reactive protein; CHD; CI; CRP; CVD; HDL-C; HR; IQR; LDL-C; MI; body mass index; cardiovascular disease; cohort; confidence interval; coronary heart disease; hazard ratio; high-density lipoprotein cholesterol; interquartile range; low-density lipoprotein cholesterol; myocardial infarction; study.