Significance of Persistent Inflammation in Patients With Chronic Coronary Syndrome: Insights From the REAL-CAD Study

Background: The prognostic implications of persistent low-grade inflammation in patients with chronic coronary syndrome (CCS) are underexplored. The REAL-CAD (Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease) study demonstrated the benefit of higher intensity pitavastatin in Japanese patients with CCS. Objectives: This prespecified subanalysis of the REAL-CAD study aimed to assess the prognostic effect of the persistent low-grade inflammation represented by high-sensitivity C-reactive protein (hs-CRP) in CCS patients. Methods: The present analysis involved patients without events until 6 months after randomization and whose hs-CRP levels were available at baseline and 6 months (n = 10,460). The primary endpoint was the composite of cardiovascular mortality, myocardial infarction, stroke, and unstable angina hospitalization. Landmark analyses evaluated the prognostic impact of continuous inflammation in 4 groups based on the median levels of hs-CRP (0.5 mg/L for both) at baseline and 6 months. The 4 groups included patient with persistently low, elevated (increased), reduced, and persistently high hs-CRP. Results: Adjusted Cox proportional hazard analyses demonstrated an increased risk of the primary endpoint in the group with persistently high hs-CRP when compared to the group with persistently low hs-CRP as a reference (adjusted HR: 1.48, 95% CI: 1.18-1.89; P = 0.001), but with a similar risk in the group with elevated (HR: 1.07, 95% CI: 0.77-1.49, P = 0.68) and reduced (HR: 0.92; 95% CI: 0.66-1.27; P = 0.60) hs-CRP. Conclusions: The study shows that persistent low-grade inflammation is associated with poor outcomes and underscores the need to address residual inflammatory risk in CCS patients.