Low-cost and fast performing indicators of muscle mass loss are good predictors of clinical outcomes in hospitalized patients: a longitudinal observational study.

BACKGROUND AND AIMS "Gold standard" methods for muscle mass (MM) assessment are expensive and difficult to use in clinical practice. The present study aimed to evaluate the association between easy-to-apply and low-cost indicators of MM and clinical outcomes in a sample of hospitalized patients. METHODS In this prospective cohort study nutritional assessment was performed within 48 hours of admission to detect MM loss: Calf circumference (CC), adductor pollicis muscle thickness (APMT), mid-arm muscle circumference (MAMC), and arm muscle area (AMA). The loss of MM was also evaluated by physical examination. Patients were followed up until discharge for collection of in-hospital death and length of hospital stay (LOS), and they were contacted by phone to assess hospital readmission and mortality at six months after discharge. RESULTS We evaluated 601 patients (55.8±14.8 years). Moderate/severe loss of MM (HR 4.12; 95% CI: 1.26-13.49), low CC (HR 3.67; 95% CI: 1.07-12.55), low MAMC (HR 5.20; 95% CI: 1.48-18.35), and low AMA (HR 14.28; 95% CI: 1.80-113.14) were predictors of in-hospital mortality. Moderate/severe loss of MM was also a predictor of prolonged LOS ((OR 2.27; 95% CI: 1.53-3.36), hospital readmission (OR 4.14; 95% CI: 1.26-13.55), and mortality at six months (OR 3.20; 95% CI: 1.71-6.01). Low CC (OR 2.49; 95% CI: 1.27-4.85) and low APMT (OR 3.22; 95% CI: 1.56-6.66) were associated with death six months after discharge. CONCLUSIONS Easy-to-apply and low-cost indicators of MM were independently associated with negative clinical outcomes and should be part of nutritional assessment in hospitals. This article is protected by copyright. All rights reserved.