Nutritional and Physical Rehabilitation in Post-Critical Coronavirus Disease 2019 (COVID-19) Ambulatory Patients: The NutriEcoMuscle Study

<b>Background</b>: The prevalence of malnutrition is high in post-intensive care unit (ICU) coronavirus disease 2019 (COVID-19) patients during hospitalization and after hospital discharge. This paper presents prospective results from the NutriEcoMuscle study, a multicenter observational study. The study aimed to evaluate changes in nutritional and functional status in post-ICU COVID-19 patients following nutritional and physical rehabilitation interventions. Secondary aims included assessing adherence to and tolerance of the oral nutritional supplement (ONS) used in the nutritional intervention. <b>Methods</b>: The study enrolled adults who had been admitted to the ICU due to severe COVID-19. At hospital discharge, the patients underwent a nutritional intervention based on oral nutritional supplements (ONSs) with 100% serum lactoprotein enriched with leucine and vitamin D and a physical rehabilitation program. They were followed up during three months. Performed assessments included Subjective Global Assessment (SGA), Global Leadership Initiative on Malnutrition (GLIM) criteria, Barthel index (BI), handgrip strength and Timed Up and Go test, bioelectrical impedance analysis (BIA), nutritional ultrasound (US), and tolerance and adherence to ONS. Sample size was calculated based on handgrip strength, and parametric and non-parametric tests were used to assess differences between the baseline and three-month outcomes. <b>Results</b>: The study included 96 patients (71.9% male, mean age 58.8 years, mean body mass index (BMI) of 28.8 kg/m², 36.5% obese). A total of 85 patients (62 men and 23 women) completed the 90-day follow-up. The mean weight gain after the intervention was 6.8 (SD 5.2) kg (similar in men and women; <i>p</i> = 0.263). The proportion of patients with malnutrition according to the SGA or GLIM criteria decreased from 100% to 11.8% and 36.4%, respectively (<i>p</i> < 0.00001 in both cases). The proportion of patients with functional limitations by BI decreased from 66.7% to 27.0% (<i>p</i> < 0.0001). Handgrip strength increased more than 40% in both men and women (<i>p</i> < 0.00001). The time to perform the Timed Up and Go (TUG) test decreased more than 40% in both men and women (<i>p</i> < 0.00001). According to BIA, the mean fat mass did not increase significantly in either men or women. The mean fat-free mass index (FFMI) increased significantly in both men and women. There were also significant increases in body cell mass, skeletal muscle mass index, and appendicular skeletal muscle mass index. The phase angle (PhA) increased significantly in both men (26.5%) and women (17.4%). In a multivariate analysis, age and baseline PhA were related to the PhA increase (adjusted R² = 0.5573). The US study showed a significant increase in the mean measurements of muscle area, muscle circumference, X-axis, and Y-axis in the rectus femoris. Regarding abdominal fat, there were no significant increases in total, superficial, or preperitoneal adipose tissue by US. Participants engaged in a median interquartile range (IQR) of 70 (0-120) min/week of strength exercise and 60 (0-120) min/week of moderate physical exercise. The supplement was well tolerated, and poor adherence (less than 50%) was low (4% of the participants). <b>Conclusions</b>: A three-month intervention, including ONS and physical rehabilitation, is associated with a significant improvement in nutritional and functional status. Patients gained weight primarily by increasing their muscle mass. There was no significant increase in fat mass, as measured by BIA or US. The intervention was well tolerated and had good adherence.