Low visceral fat volume and hypoalbuminemia as prognostic markers in hospitalized patients with coronavirus disease 2019 during the omicron variant epidemic

Background & aims

The rate of severe cases of coronavirus disease 2019 (COVID-19) has decreased since the Omicron variant became epidemic. Visceral fat volume was a risk factor for COVID-19 severity with prior prevalent variants, but whether visceral fat volume remains a risk factor for the Omicron variant is unclear. We investigated the associations of clinical factors including visceral fat volume with severity and mortality among hospitalized patients with COVID-19 during the Omicron variant epidemic.

Methods

This was a single-center retrospective cohort study conducted at the Teikyo University Hospital in Japan. We included hospitalized patients with COVID-19 during the Omicron variant epidemic who underwent computed tomography of the abdomen. Clinical data were obtained from the medical records and visceral fat area (VFA) was measured using a 3-dimensional image analysis system volume analyzer. Severity was determined by the presence or absence of oxygen supplementation.

Results

Among the 226 patients, 66 patients showed moderate severity and 29 patients were non-survivors. Hypoalbuminemia was associated with severity (odds ratio [OR] 3.93, 95 % confidence interval [CI] 1.91–8.07; p = 0.0002), and hypoalbuminemia (OR 8.38, 95%CI 2.37–29.58; p = 0.0010) and low VFA (OR 3.40, 95%CI 1.15–10.06; p = 0.027) were associated with mortality. Decision tree analysis showed that mortality rate in the hypoalbuminemia and low-VFA group (37.3 %) was significantly higher than in other groups (p ≤ 0.01).

Conclusions

Low visceral fat volume and hypoalbuminemia were associated with mortality in hospitalized patients with COVID-19 during the Omicron variant epidemic. Classification by VFA and serum albumin may allow simple prediction of mortality risk among hospitalized patients with COVID-19.