Prognostic significance of novel muscle quality index utilization in hospitalized adults with cancer: A secondary analysis.

Abstract

This study aimed to investigate and propose novel approaches to calculate muscle quality index (MQI) using muscle mass derived from single-frequency bioelectrical impedance analysis (SF-BIA) and calf circumference in both unadjusted and body mass index (BMI)-adjusted forms. In addition, we examined their prognostic significance in patients with cancer. A secondary analysis was conducted on a prospective cohort study of patients with cancer. Handgrip strength was measured. SF-BIA was conducted to estimate appendicular lean soft tissue (ALST, in kilograms). MQI was calculated using three approaches: (1) the ratio of handgrip strength to ALST (MQISF-BIA), (2) the ratio of handgrip strength to calf circumference (MQIcalf circumference), and (3) the ratio of handgrip strength to BMI-adjusted calf circumference (MQIadj. calf circumference). Maximally selected log-rank was calculated to estimate their cutoff values to predict survival. Two hundred eighty-four patients were included (51.1% men; median age, 61 years). Solid tumors were the most frequent (89.8%). All approaches to MQI (MQISF-BIA, MQIcalf circumference, and MQIadj. calf circumference) were independent predictors of 6-month mortality. The found cutoffs were (1) MQISF-BIA (<1.52 for men, <0.63 for women), (2) MQIcalf circumference (<0.74 for men, <0.24 for women), and (3) MQIadj. calf circumference (<0.75 for men, <0.25 for women). This study introduces MQISF-BIA, MQIcalf circumference, and MQIadj. calf circumference as future potential surrogate methods for computing MQI in clinical practice when other robust procedures are unavailable, pending further validation.