Prognostic impact of elevated baseline CRP levels in primary PCI-treated patients with residual cholesterol risk

Abstract

Abstract Background Recent large randomized studies have indicated the potential of anti-inflammatory therapies to reduce adverse cardiovascular events in patients with myocardial infarction, with the most pronounced benefit in patients with baseline elevated C-reactive protein (CRP). Purpose Our aim was to assess the association of CRP levels with 30-day and 1-year mortality in patients with acute myocardial infarction treated with primary PCI and with residual cholesterol risk. Methods The study included 1531 patients admitted for primary PCI, with the residual cholesterol risk, i.e. low-density lipoprotein cholesterol (LDL-C) levels of >1.80 mmol/l (70 mg/dl), from a prospectively kept electronic registry of a high-volume tertiary center, for whom in-hospital CRP measurements were available. Elevated CRP was defined as ≥5 mg/l (local laboratory cut off value), measured during index hospitalization. Cox regression models were constructed to assess the impact of elevated CRP on 30-day and 1-year mortality. Results 72% of the included patients with LDL-C >1.80 mmol/l had elevated in-hospital CRP (n=1107). Compared with patients with CRP levels within reference limit, elevated CRP was associated with older age (62 vs. 60, p<0.001), higher rates of diabetes (25.8% vs. 18.5%, p=0.002), renal failure (6.4% vs. 2.1%, p<0.001) and Killip class >1 at presentation (22.5% vs. 12.3%, p<0.001), as well as lower EF (44% vs. 48%, p<0.001) and lower haemoglobin on admission (13.9 g/dl vs. 14.2 g/dl, p<0.001). Crude mortality rates were increased in patients with CRP ≥5mg/l at both 30 days (6.0% vs. 2.4%, p=0.003) and 1 year (13.2% vs. 6.3%, p<0.001) (Figure). After adjusting for the observed baseline differences, CRP ≥5mg/l remained an independent predictor of mortality at 1 year (HR 1.691, 95% CI: 1.050–2.724, p=0.03), but not at 30 days (HR 1.690, 95% CI: 0.859–3.324, p=0.13). Conclusion In primary PCI-treated patients with residual cholesterol risk, elevated in-hospital CRP was independently associated with 1-year mortality. Our findings may thus suggest a potential window of opportunity, for anti-inflammatory therapies to improve outcomes beyond the acute phase. Figure 1 Funding Acknowledgement Type of funding source: None