Prognostic value of longitudinal assessment of inflammatory and nutritional status in patients undergoing valvular heart surgery
Authors: Hung D , Tse Y K , Ren Q W , Huang J Y , Yiu K H 
Published: January 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Novel strategies to improve the long-term risk stratification of valvular surgery are urgently needed as a result of the increasing prevalence of valvular heart diseases globally.

Purpose
This study aimed to evaluate the prognostic implications of longitudinal assessment of inflammatory and nutritional status in patients undergoing valvular surgery.

Methods
1046 patients who underwent valvular surgery were stratified into three groups based on their inflammatory (neutrophil-to-lymphocyte ratio [NLR]) and nutritional status (prognostic nutritional index [PNI]): without inflammation and malnutrition (normal), inflammation or malnutrition alone (mild), and concomitant inflammation and malnutrition (severe). Optimal NLR and PNI thresholds for predicting all-cause mortality were determined using receiver-operating characteristic analysis. The endpoints were all-cause mortality, cardiovascular death and adverse events (composite of death and heart failure [HF] hospitalization).

Results
Over a median follow-up of 4.3 years (IQR: 2.6 to 6.4 years), 139 (13.3%) deaths and 148 (14.1%) HF hospitalizations occurred. Based on the optimal cut-off of NLR &gt;4.06 (inflammation) and PNI &lt;45.8 (malnutrition), 714 (68.3%), 214 (20.5%) and 118 (11.3%) patients were categorized into normal, mild and severe groups respectively. Compared with patients without inflammation and malnutrition, those with concomitant inflammation and malnutrition before surgery had the highest risk of all-cause mortality (hazard ratio [HR] 5.60, 95% confidence interval [CI] 3.66-8.57), cardiovascular death (subdistribution HR [SHR] 5.19, 95% CI 2.33-11.60) and adverse events (HR 3.14, 95% CI 2.25-4.38) (p&lt;0.001 for all), adjusted for demographics, cardiovascular risk factors and diseases, medications, valvular surgeries and EuroSCORE II. Discriminatory improvement for predicting all-cause mortality was observed when baseline NLR and PNI were added to EuroSCORE II (C-statistic 0.77 vs 0.73, p=0.04; continuous net reclassification improvement [cNRI] 0.24, 95% CI 0.12-0.36, p=0.004; integrated discrimination improvement [IDI] 0.04, 95% CI 0.01-0.08, p=0.004) and STS score (C-statistic 0.78 vs 0.73, p=0.03; cNRI 0.16, 95% CI 0.06-0.32, p=0.002; IDI 0.02, 95% CI 0.000-0.049, p=0.048) respectively. 1 year following surgery (n=740), those with persistent concomitant inflammation and malnutrition experienced the highest risk of all-cause mortality (HR 8.82, 95% CI 4.21-18.49), cardiovascular death (SHR 12.63, 95% CI 3.85-41.39) and adverse events (HR 5.83, 95% CI 3.16-10.76) than those without (p&lt;0.001 for all).

Conclusion
Concomitant inflammation and malnutrition is common and is strongly associated with mortality and HF in patients undergoing valvular surgery. Beyond conventional risk scores, assessments of inflammatory and nutritional status using NLR and PNI before and after surgery may provide additional prognostic value for long-term outcomes following valvular surgery.