Body Mass Index, High-Sensitivity C-Reactive Protein and Mortality in Chinese with Coronary Artery Disease

BACKGROUND To investigate single and joint associations of body mass index (BMI) and serum high-sensitivity C-reactive protein (hsCRP) with death. METHODS The study included 1871 coronary artery disease (CAD) patients aged 40-85 year-old recruited from 2008 to 2011. Cox regression models were used to estimate the association of BMI and hsCRP with mortality. The data was analyzed in 2014. RESULTS During 3.1 years follow-up, 141 deaths were recorded, 110 died of cardiovascular disease (CVD). After adjustment of major CVD risk factors, there was a J-shaped association between BMI and all-cause and CVD mortality, and a positive association between hsCRP and mortality. The J-shaped association of BMI with mortality was present among patients who never smoked or with elevated hsCRP (≥3.0 mg/L). Compared with overweight (BMI 24-27.9 kg/m2) patients with normal hsCRP (<3.0 mg/L), obese patients (BMI≥28 kg/m2) with elevated hsCRP had a 3.41-fold risk of all-cause mortality (95% CI 1.49-7.80) and a 3.50-fold risk of CVD mortality (1.40-8.75), lean patients (BMI<24 kg/m2) with elevated hsCRP concentration had a 2.54-fold risk of all-cause mortality (1.36-4.74) and a 2.36-fold risk of CVD mortality (1.19-4.70). CONCLUSIONS The association pattern between baseline BMI and mortality changed among different baseline hsCRP concentrations, indicating that low-grade inflammation may be related to BMI and secondary prognosis of CAD.