Concomitant inflammation and malnutrition predicts mortality and heart failure in coronary artery disease

Coronary artery disease (CAD) is the leading cause of death globally. Recent studies have shown that inflammation and malnutrition are associated with poor prognosis in CAD. Nonetheless, the prognostic role of blood inflammatory markers and nutritional indices for risk stratification in CAD remains unknown. The aim of this study is to investigate the prognostic value of concomitant inflammation and malnutrition in a CAD population. This was a retrospective cohort study of 2003 patients diagnosed with CAD (median age=66.0±11.6, 73.1% male) from our Hospital. Patients were stratified into three groups according to their inflammatory (using neutrophil-to-lymphocyte ratio [NLR]) and nutritional status (using prognostic nutritional index [PNI]) at baseline: (1) absence of inflammation and malnutrition (normal), (2) inflammation or malnutrition alone (mild), and (3) concomitant inflammation and malnutrition (severe). Optimal NLR and PNI thresholds for predicting all-cause mortality were determined using receiver-operating characteristic curve analysis. The primary endpoint was all-cause mortality at median 4.5 years follow-up, and secondary endpoints were heart failure (HF) hospitalisation and adverse outcomes, defined as the composite of all-cause mortality and HF hospitalisation. Survival was compared using Kaplan-Meier and log-rank tests. Multivariable Cox regression and Fine-Gray competing risk models (for HF hospitalization) assessed associations with outcomes. 48.9%, 35.4%, and 15.6% of patients were classified into normal, mild, and severe groups, respectively. There was significant interaction between baseline NLR and PNI for the risk of HF hospitalisation (Pinteraction<0.001). There was a graded increase in incidence rates of mortality (6.5% vs 12.5% vs 41.5%, log-rank P<0.001), HF hospitalisation (4.9% vs 8.3% vs 16.6%, log-rank P<0.001), and adverse outcomes (9.9% vs 17.7% vs 47.9%, log-rank P<0.001) from normal to mild to severe groups. After multivariate adjustment, mild and severe groups had a significantly higher risk than the normal group in terms of mortality (hazard ratio [HR] 1.63, 95%CI 1.17-2.2, P=0.004 and HR 2.35, 95%CI 2.00-2.77, P<0.001 respectively), heart failure hospitalisation (subdistribution hazard ratio [SHR] 1.63, 95%CI 1.10-2.42, P=0.015 and SHR 1.69, 95%CI 1.35-2.12, P<0.001), and adverse outcomes (HR 1.55, 95%CI 1.19-2.04, P=0.001 and HR 2.05, 95%CI 1.78-2.36, P<0.001), with a clear step-up in incidence rates and risks for the severe group. In patients with CAD, concomitant inflammation and malnutrition is common and is strongly associated with increased mortality and heart failure hospitalisation. Routine assessment of this combined immuno-nutritional status offers a simple, accessible tool to refine risk stratification and guide clinical management.Kaplan meier on death, HF, adverse eventFor image description, please refer to the figure legend and surrounding text.