Prognostic Value of Baseline Inflammation in Diabetic and Nondiabetic Patients Undergoing Percutaneous Coronary Intervention

Background: There is a paucity of data on the prognostic value of high-sensitivity C-reactive protein (hsCRP) levels in diabetic and nondiabetic patients undergoing percutaneous coronary intervention (PCI). Methods: All patients with known baseline hsCRP undergoing PCI at a single tertiary care centre from 2010 to 2017 were included. High hsCRP was defined as > 3 mg/L. Known causes of elevated hsCRP levels and hsCRP > 10 mg/L represented exclusion criteria. The 1-year primary outcome was major adverse cardiovascular events (MACE), including all-cause mortality, myocardial infarction (MI), and target-vessel revascularisation (TVR). Results: Among a total of 11,979 patients included, high hsCRP levels were observed in 24.7% of patients without diabetes and 29.8% of patients with diabetes (P < 0.001). Both diabetics and nondiabetics with high hsCRP levels had increased rates of MACE compared with their counterparts with low hsCRP (diabetics: adjusted hazard ratio [aHR] 1.58, 95% CI 1.27-1.96; nondiabetics: aHR 1.45, 95% CI 1.13-1.86; P interaction = 0.981) primarily driven by increased rates all-cause deaths (diabetics: aHR 2.32, 95% CI 1.42-3.80; nondiabetics: aHR 3.14, 95% CI 1.74-5.65; P interaction = 0.415). Although high hsCRP levels were associated with increased rates of TVR (aHR 1.35, 95% CI 1.04-1.75) and MI (aHR 1.86, 95% CI 1.18-2.93) only in patients with diabetes, no significant interactions were observed between inflammation and diabetes (P interaction = 0.749 and 0.602, respectively). Conclusions: Patients undergoing PCI with high levels of hsCRP, defined as > 3 mg/L, have worse ischemic outcomes regardless of diabetes status.