Optimized nutritional management mitigates short-term muscle mass loss in elderly frail patients with COVID-19: a randomized controlled trial

Abstract

Abstract Background The COVID-19 pandemic has spread rapidly worldwide, highlighting the vulnerability of elderly individuals with frailty as a risk factor for adverse outcomes. Aim This study was designed to investigate whether early and appropriate nutritional intervention can mitigate skeletal muscle mass loss and improve clinical outcomes in frail older adults compared with standard hospital diet. Methods A randomized controlled trial was conducted in a general hospital in China from January to March 2023. Eligible patients provided informed consent and were randomly assigned to either the hospital diet group or the optimized diet group. The primary endpoint of the study was ΔSMI (change in skeletal muscle index between day 7 post-feeding and admission). Secondary endpoints included several indicators of body composition such as fat-free mass (FFM), skeletal muscle mass (SMM), extracellular water/total body water ratio (ECW/TBW), visceral fat area (VFA), and phase angle. Clinical outcomes were mortality, intensive care unit (ICU) admission, and length of hospital stay. Results Fifty-five patients were recruited and analyzed between January and March 2023. Patients in the optimized diet group received a mean of 1.0 (SD 0.06) g/kg per day protein compared with 0.8 (SD 0.07) g/kg per day in the hospital diet group (P = 0.02). The average daily intake over 7 days was 26 (SD 6.1) kcal/kg for the optimized diet group and 21 (SD 7.2) kcal/kg for the hospital diet group(P = 0.0171). Both groups showed a reduction in skeletal muscle index (SMI), with participants receiving the optimized diet intervention showing a comparatively smaller decrease in SMI compared to those on the hospital diet (0.57 [SD 0.08] kg/m2 vs. 0.16 [SD 0.07] kg/m2, P = 0.0003). The other parameters, including fat-free mass, visceral fat area, ECW/TBW ratio, and phase angle, did not show significant differences between the two groups. During hospitalization, two patients in the hospital diet group and one patient in the optimized diet group succumbed to respiratory failure as the direct cause of death. However, there was no statistically significant difference in mortality between the two groups (P > 0.99). The mean duration of hospital stay for patients in the optimized diet group was 12.3 days, which was significantly shorter compared to the hospital diet group with a mean duration of 14.4 days (P = 0.0211). Conclusions Our study results suggest that early, appropriate, and rational optimization of diet may mitigate short-term muscle mass loss while reducing hospital stay.