Background: Baseline C-reactive protein (CRP) levels predict major adverse cardiovascular events (MACE: death, myocardial infarction, stroke, coronary revascularization, and hospitalization for unstable angina). The association between changes in CRP levels with plaque progression and MACE in the setting of maximally intensive statin therapy is unknown.
Methods and results: The Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The treatment groups did not differ significantly in the change from baseline of percent atheroma volume on intravascular ultrasound, CRP-modulating effects, or MACE rates, thus allowing for a (prespecified) post hoc analysis to test associations between the changes in CRP levels with coronary disease progression and MACE. Patients with nonincreasing CRP levels (n=621) had higher baseline (2.3 [1.1-4.7] versus 1.1 [0.5-1.8] mg/L; P<0.001) and lower follow-up CRP levels (0.8 [0.5-1.7] versus 1.6 [0.7-4.1] mg/L; P<0.001) versus those with increasing CRP levels (n=364). Multivariable analysis revealed a nonincreasing CRP level to independently associate with greater percent atheroma volume regression (P=0.01). Although the (log) change in CRP did not associate with MACE (hazard ratio, 1.18; 95% confidence interval, 0.93-1.50; P=0.17), the (log) on-treatment CRP associated significantly with MACE (hazard ratio, 1.28; 95% confidence interval, 1.04-1.56; P=0.02). On-treatment low-density lipoprotein cholesterol levels did not correlate with MACE (hazard ratio, 1.09; 95% confidence interval, 0.88-1.35; P=0.45).
Conclusions: Following 24 months of potent statin therapy, on-treatment CRP levels associated with MACE. Inflammation may be an important driver of residual cardiovascular risk in patients with coronary artery disease despite aggressive statin therapy.
Clinical trial registration url: http://clinicaltrials.gov. Unique identifier: NCT000620542.
Trial registration: ClinicalTrials.gov NCT00620542.
Keywords: C-reactive protein; atherosclerosis; atorvastatin; cholesterol, LDL; inflammation; rosuvastatin; ultrasonography.