Long-term prognostic value of concomitant inflammation and malnutrition in patients undergoing valvular heart surgery
Authors: Hung D , Tse Y K , Ren Q W , Huang J Y , Yiu K H 
Published: October 2022

Abstract

Background
Recent studies have shown that inflammation and malnutrition are associated with poor prognosis in valvular heart diseases. Nonetheless, the prognostic role of blood inflammatory markers and nutritional indices for risk stratification in valvular heart surgery remains unknown.

Purpose
This study aimed to evaluate the long-term prognostic implications of inflammatory and nutritional status in predicting survival and adverse outcomes in patients who underwent valvular heart surgery.

Methods
1048 patients who underwent valvular heart surgery between 2012 and 2020 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, (2) inflammation or malnutrition alone, and (3) concomitant inflammation and malnutrition. Optimal NLR and PNI thresholds for predicting all-cause mortality were determined using receiver-operating characteristic curve analysis. The discriminatory capacity of NLR and PNI adding to EuroSCORE II was assessed with continuous net reclassification (cNRI) and integrated discrimination improvement (IDI) indices. The endpoints of interest included all-cause mortality, cardiovascular (CV) death and adverse events (defined as the composite of death and heart failure [HF] hospitalization).

Results
Over a median follow-up of 3.9 years (IQR: 2.0 to 6.1 years), 139 (13.3%) deaths, in which 51 (4.9%) were due to cardiovascular causes, and 109 (10.4%) HF hospitalizations occurred. Based on the optimal cutoff of NLR&gt;4.06 (inflammation) and PNI&lt;45.8 (malnutrition), 714 (68.1%), 214 (20.4%) and 120 (11.5%) patients were categorized into groups 1, 2 and 3 respectively. Compared to those without inflammation and malnutrition, patients with concomitant inflammation and malnutrition had the highest risk of all-cause mortality (hazard ratio [HR] 4.90, 95% confidence interval [CI] 3.21–7.49), CV death (subdistribution HR [SHR] 5.19, 95% CI 2.33–11.6) and adverse events (HR 3.09, 95% CI 2.21–4.31) (p&lt;0.001 for all), adjusted for demographics, cardiovascular risk factors and diseases, medications, valvular surgeries and EuroSCORE II (Figure 1). When added to EuroSCORE II, NLR and PNI provided incremental prognostic value (χ2 increased from 76.6 to 118.4, p&lt;0.001) and discrimination improvement (cNRI=0.23; IDI=0.03, p&lt;0.001 for both) for predicting all-cause mortality (Figure 2). Patients with concomitant inflammation and malnutrition after the surgery also had the worst survival and adverse outcomes when compared with the other groups.

Conclusions
Concomitant inflammation and malnutrition is common and is strongly associated with mortality and HF in patients undergoing valvular heart surgery. The assessment of preoperative and postoperative inflammatory and nutritional status of patients could be useful for the prognostication of valvular surgery.

Funding Acknowledgement
Type of funding sources: None.