The association between reduced calf and mid-arm circumferences and ICU mortality in critically ill COVID-19 patients

Abstract

Background & aims: Patients with COVID-19 are at a high risk of malnutrition caused by inflammatory syndrome and persistent hypermetabolism, which may affect clinical outcomes. This study aimed to evaluate the changes in nutritional status indicators between two time points of nutritional assessments of COVID-19 patients during their stay in the intensive care unit (ICU). Moreover, the study also assessed the association of nutritional status with ICU mortality.

Methods: This cohort study included retrospective data of adult patients admitted to a public hospital ICU in southern Brazil, between March and September 2020. These participants with confirmed COVID-19 diagnosis received nutritional assessment within the first 72 h after ICU admission. The anthropometric measurements collected included mid-arm circumference (MAC) and calf circumference (CC). The percentage (%) of MAC adequacy was calculated, and values < 50th percentile for sex and age were considered low. CC values of ≤33 cm for women and ≤34 cm for men were indicative of reduced muscle mass. Data on the date of discharge from the ICU and mortality outcome were collected.

Results: A total of 249 patients were included (53.4% men, 62.2 ± 13.9 years of age, SOFA severity score 9.6 ± 3.5). Of these, 22.7 and 39.1% had reduced MAC and CC at ICU admission, respectively. In these participants, weight, MAC, CC, and % MAC decreased significantly from the first to second nutritional assessment (p < 0.05), but there was no significant difference between survivors and non-survivors. Patients with reduced CC (HR = 2.63; 95% CI 1.65-4.18) or reduced MAC (HR = 2.11; 95% CI 1.37-3.23) at the first nutritional assessment had approximately twice the risk of death in the ICU than those with normal CC and normal MAC, regardless of the severity assessed by the SOFA score and age.

Conclusion: Reduced MAC and CC values were identified in approximately 20 and 40% of COVID-19 patients admitted to the ICU, respectively. Additionally, these indicators of nutritional depletion were associated with an approximately 2-fold increase in the risk of ICU mortality. A significant reduction in anthropometric indicators during the first weeks of ICU stay confirmed the deterioration of nutritional status in these patients, although this was not associated with mortality.

Keywords: COVID-19; Intensive care units; Nutritional assessment; Nutritional status.