Muscle waste assessment during intensive care unit and general ward stay in patients receiving early nutritional support: An observational cohort study.

BACKGROUND & AIMS: Hospitalization-associated muscle wasting (MW), affecting up to 15% of muscle mass weekly, is exacerbated by critical illness, immobility, and suboptimal nutrition. This study aims to describe MW progression and the impact of early enteral nutrition (EN) or total parenteral nutrition (TPN) nutritional support.

METHODS

A prospective observational cohort study including adults (≥18 years old) admitted to either the general ward or the intensive care unit (ICU) who required at least 7 days of EN/TPN; Muscle mass (bioelectrical impedance, ultrasound), grip strength, weight, body mass index (BMI), and phase angle were measured at baseline (pre-nutrition) and 7 days post-intervention. Subgroup and adjusted analyses compared nutrition type, protein supplementation (30 g leucine-enriched module), and malnutrition severity (subjective global assessment, SGA).

RESULTS

120 patients were enrolled, comprising 37 general wards and 83 ICU patients. In the ICU cohort, significant reductions from baseline were observed in weight (-4.4%, p = 0.004), BMI (-1.2%, p = 0.006), and muscle thickness (-6.9%, p = 0.007). Grip strength declined universally around 5-10 kg (up to -39.8% in ICU). EN better preserved muscle mass versus TPN (-2% loss with TPN vs +2% weight gain with EN; adjusted β: -5.2%, 95% CI: -9.1 to -1.3; p = 0.009). Protein supplementation attenuated declines in hand grip strength (adjusted β: +24.1%, 95% CI: +5.3 to +42.9; p = 0.012). SGA-B (moderately malnourished) patients lost weight (-2.8%, p = 0.016), while SGA-C (severely malnourished) stabilized. Phase angle increased in general ward patients (+10.8%, p = 0.064), indicating improved cellular hydration.

CONCLUSIONS

Early nutritional support attenuated but did not prevent MW, with ICU patients suffering greater structural loss and all patients experiencing pronounced functional decline. EN appeared superior for muscle preservation over TPN. Protein supplementation showed clinically relevant protective trends, and phase angle served as a useful marker of cellular recovery. Stratified nutrition strategies based on care setting and SGA status are recommended to mitigate MW.