Impact of C-reactive protein levels and role of anakinra in patients with ST-elevation myocardial infarction

Background: Interleukin-1 blockade with anakinra reduces C-reactive protein (CRP) levels and prevents heart failure (HF) events after ST-segment myocardial infarction (STEMI). The effectiveness of anakinra according to the degree of systemic inflammation in STEMI has not been addressed. Methods: We analyzed 139 patients from three Virginia Commonwealth University Anakinra Response Trial randomized clinical trials to assess whether CRP levels predicted HF hospitalization or death in patients with STEMI, and if CRP levels influenced the effects of treatment with anakinra. Results: CRP cut-off levels for prediction of the composite of death or HF hospitalization for CRP at admission, 3 and 14 days were, respectively 6.45 mg/L (100% of sensitivity and 66.1% specificity), 26 mg/L (100% of sensitivity and 78% specificity) and 9.56 mg/L (100% of sensitivity and 80% specificity). More patients with elevated CRP levels died or had a HF hospitalization (5/47 [11%] vs 0/82 [0%], p = 0.004 for CRP at admission; 5/32 [15.6%] vs 0/92 [0%], p < 0.001 for day 3 and 5/26 [19%] vs 0/89 [0%], p < 0.001 for day 14). A greater number of patients treated with anakinra had low CRP levels at 3 and 14 days compared to placebo (Odds Ratio 0.11 [95% IC 0.04-0.28], p < 0.0001 and OR 0.35 [95% CI 0.14-0.86], p = 0.02, respectively). Anakinra significantly prevented death or HF hospitalization in patients with high inflammatory burden (p = 0.04 for admission, p = 0.24 for day 3, and p = 0.05 for day 14). Conclusion: Patients with elevated CRP had higher incidence of HF hospitalization or death. Anakinra reduced the number of patients with elevated CRP levels and prevented death or HF hospitalization in patients with elevated CRP levels.