hsCRP Level and the Risk of Death or Recurrent Cardiovascular Events in Patients With Myocardial Infarction: a Healthcare‐Based Study

BACKGROUND: Beyond the controlled setting of trials, scarce information exists on the burden, predictors, and outcomes associated with elevated hsCRP (high‐sensitivity C‐reactive protein) in “real‐world” patients with myocardial infarction (MI). METHODS AND RESULTS: We included all‐coming MI survivors undergoing hsCRP testing >30 days after an MI during routine health care in Stockholm, Sweden (2006–2011). hsCRP tests measured during hospitalization/emergency department visits, followed by antibiotics or indicative of acute illness, were excluded, together with patients with ongoing/recent cancer, chronic infections, or immunosuppression. Inflammation was defined over a 3‐month baseline window and associated with subsequent death and major adverse cardiovascular events (composite of MI, ischemic stroke, or cardiovascular death). Included were 17 464 patients (63% men; mean age, 72.6 years) with a median hsCRP level of 2.2 (interquartile range, 1.0–6.0) mg/L and a median of 2.2 (interquartile range, 0.8–4.9) years since their MI. Most (66%) had hsCRP ≥2 mg/L, and 40% had hsCRP >3 mg/L. Lower hemoglobin, lower estimated glomerular filtration rate, and comorbidities (eg, heart failure, peripheral vascular disease, stroke, atrial fibrillation, diabetes mellitus, and rheumatoid diseases) were associated with higher odds of hsCRP ≥2 mg/L. Conversely, previous percutaneous coronary intervention, ongoing renin‐angiotensin blockade, and statins were associated with lower hsCRP ≥2 mg/L odds. Patients with hsCRP ≥2 mg/L were at higher risk of major adverse cardiovascular events (n=3900; adjusted hazard ratio, 1.28; 95% CI, 1.18–1.38) and death (n=4138; adjusted hazard ratio, 1.42; 95% CI, 1.31–1.53). Results were robust across subgroups of patients and after exclusion of events occurring during the first 6 to 12 months. On a continuous scale, the association between hsCRP and outcomes was linear until hsCRP >5 mg/L, plateauing thereafter. CONCLUSIONS: Most patients with MI exhibit elevated hsCRP levels. Besides identifying populations at high‐inflammatory risk, this study extends the prognostic validity of this biomarker from trial evidence to real‐world healthcare settings.