Association between temporal changes in C-reactive protein levels and prognosis in patients with previous myocardial infarction - A report from the CHART-2 Study

Abstract

BackgroundSeveral studies have reported that C-reactive protein (CRP), an inflammatory biomarker, predicts cardiovascular events independently of low-density lipoprotein cholesterol levels. However, no study examined whether temporal changes in CRP levels are associated with clinical events in patients with previous myocardial infarction (MI). Methods and resultsWe examined 2184 consecutive patients with previous MI and CRP data at baseline in the Chronic Heart Failure Registry and Analysis in the Tohoku district-2 (CHART-2) Study. During the median 6.4 years follow-up, 592 all-cause, 245 cardiovascular, and 273 non-cardiovascular deaths occurred. Patients with CRP ≥ 2.0 mg/L at baseline had significantly increased incidence of all-cause (hazard ratio (HR) 1.68, P < 0.001) and non-cardiovascular death (HR 1.86, P < 0.001), compared with those with CRP < 2.0 mg/L. Temporal changes in CRP levels were associated with prognosis; among patients with CRP ≥ 2.0 mg/L at baseline, those with CRP ≥ 2.0 mg/L at 1-year had significantly increased incidence of all-cause (HR 2.12, P < 0.001), cardiovascular (HR 2.31, P < 0.001), and non-cardiovascular death (HR 2.29, P < 0.001). Among patients with CRP < 2.0 mg/L at baseline, those with CRP ≥ 2.0 mg/L at 1-year had significantly increased incidence of all-cause (HR 1.76, P < 0.001) and cardiovascular death (HR 2.10, P = 0.001). These results remained significant after adjusted with the inverse probability of treatment weighted models using propensity sore. Furthermore, as compared with patients with CRP < 2.0 mg/L at both baseline and 1-year, those with CRP ≥ 2.0 mg/L at both baseline and 1-year had increased incidence of all-cause, cardiovascular, and non-cardiovascular death. ConclusionsThese results provide the evidence that temporal increases in CRP levels are associated with increased clinical events in patients with previous MI.