# Serum omentin and chemerin levels in patients with coronavirus disease 2019

## TL;DR

This study found that chemerin levels are elevated in hospitalized COVID-19 patients, suggesting a role in the inflammatory response, while omentin levels remain unchanged.

## Contribution

The study identifies sustained elevated chemerin levels in non-critically ill hospitalized COVID-19 patients.

## Key findings

- Baseline chemerin levels were significantly higher in COVID-19 patients compared to controls.
- Chemerin levels remained elevated in patients at Day 7 of hospitalization.
- Omentin levels did not differ between patients and controls and remained stable over time.

## Abstract

Chemerin and omentin are adipokines secreted mainly by visceral adipose tissue, with pro- and anti-inflammatory properties, respectively. Their role in coronavirus disease 2019 (COVID-19) remains incompletely understood and available data are inconsistent.

This single-center case-control study included 40 hospitalized patients with COVID-19 and 24 non-COVID controls. Serum samples were collected in COVID-19 patients on admission (Day 0) and on Day 7 of hospitalization, and once in controls. Concentrations of omentin and chemerin and routine laboratory parameters were measured using enzyme immunoassays.

Compared with controls, patients with COVID-19 had higher inflammatory markers, including C-reactive protein, ferritin, interleukin-6 and D-dimer. Baseline serum omentin concentrations did not differ between COVID-19 patients and controls (363.6 [245.2–513.0] vs. 368.9 [254.1–468.8] ng/mL; p = 0.994), and remained stable between Day 0 and Day 7 (p = 0.605). In contrast, baseline chemerin levels were significantly higher in COVID-19 patients than in controls (234.3 [164.9–269.9] vs. 144.7 [98.0–213.2] ng/mL; p = 0.001) and remained elevated at Day 7 (243.7 [171.0–376.7] ng/mL, p = 0.001 vs. controls), with a non-significant trend toward an increase over time (Δ chemerin +42.6 ng/mL; p = 0.071).

In this cohort of hospitalized but predominantly non-critically ill patients, COVID-19 was associated with sustained elevation of circulating chemerin but not with alterations in omentin levels. Our findings are consistent with a potential role for chemerin, but not omentin, in the systemic inflammatory response to SARS-CoV-2 infection and complement previous reports describing divergent adipokine profiles in COVID-19.