Impact of nutritional assessment and body mass index on cardiovascular outcomes in patients with stable coronary artery disease

Background An inverse association between obesity, as defined by body mass index (BMI) and prognosis has been reported in patients with cardiovascular disease (“obesity paradox”). The aim of this study was to investigate whether adding nutritional information to BMI provides better risk assessment in patients undergoing elective percutaneous coronary intervention (PCI). Method This study comprised 1004 patients undergoing elective PCI. We calculated each patient's controlling nutritional status (CONUT) score for nutritional screening at baseline. Patients were divided into 4 groups based on CONUT score (low, 0–1 [< 75th percentile]; or high, ≥ 2 [≥ 75th percentile]) and BMI (normal, 18.5–24.9 kg/m²; or high, ≥ 25 kg/m²). The endpoint was major adverse cardiac events (MACE) defined as cardiac death and/or myocardial infarction. Results Low CONUT score + normal BMI, low CONUT score + high BMI, high CONUT score + normal BMI, and high CONUT score + high BMI were determined in 374, 242, 275, and 113 patients, respectively. During a median follow-up of 1779 days, 73 events occurred. High CONUT score + normal BMI showed a 2.72-fold increase in the incidence of MACE (95% CI 1.46–5.08, p = 0.002) compared with low CONUT score + normal BMI after adjusting for confounding factors. On the other hand, no significant difference in the incidence of MACE was observed in the other three groups. Conclusion The combination of CONUT score and BMI was a useful predictor of MACE in this population. Using BMI to assess the cardiovascular risk may be misleading unless the nutritional information is considered.