Nutritional Indices Predict All Cause Mortality in Patients with Multi-/Rifampicin-Drug Resistant Tuberculosis

Background: Multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB) with high mortality remains a public health crisis and health security threat. This study aimed to explore the predictive value of nutritional indices for all-cause mortality (ACM) in MDR/RR-TB patients. Methods: We retrospectively recruited MDR/RR-TB patients between January 2015 and December 2021, randomly assigning them to training and validation cohorts. Patients were divided into high nutritional risk groups (HNRGs) and low nutritional risk groups (LNRGs) based on the optimal cut-off value obtained from receiver operating characteristic (ROC) analyses of the hemoglobin-albumin-lymphocyte-platelet (HALP) score, prognostic nutritional index (PNI), and controlling nutritional status (CONUT) score. In the training cohort, Kaplan-Meier survival curves and Log rank tests were used to compare overall survival (OS) between the groups. Cox risk proportion regression analyses were used to explore the risk factors of ACM in patients with MDR/RR-TB. The predictive performance of ACM was assessed using area under the curve (AUC), sensitivity and specificity of ROC analyses. Results: A total of 524 MDR/RR-TB patients, with 255 in the training cohort and 269 in the validation cohort, were included. Survival analyses in the training cohort revealed significantly lower OS in the HNRGs compared to the LNRGs. After adjusting for covariates, multivariate analysis identified low HALP score, low PNI and high CONUT score were independent risk factors for ACM in MDR/RR-TB patients. ROC analyses demonstrated good predictive performance for ACM with AUCs of 0.765, 0.783, 0.807, and 0.811 for HALP score, PNI, CONUT score, and their combination, respectively. Similar results were observed in the validation set. Conclusion: HALP score, PNI, and CONUT scores could effectively predict ACM in patients with MDR/RR-TB. Hence, routine screening for malnutrition should be given more attention in clinical practice to identify MDR/RR-TB patients at higher risk of mortality and provide them with nutritional support to reduce mortality. Keywords: multidrug- and rifampicin- resistant tuberculosis, all- cause mortality, nutrition