Association between volume of lung damage and endoplasmic reticulum stress expression among severe COVID-19 ICU patients

Abstract Objective and design : single-center retrospective study to explore association between endoplasmic reticulum stress (ERS) and lung damage volume (LDV) among severe COVID-19 patients in intensive unit care (ICU) .Subjects : 63 severe COVID-19 ICU patients with a chest computer tomography 24hours before/after admission.Methods two multivariate linear regression models looking for factors associated with plasma levels of 78kDa-Glucose-Regulated Protein (GRP78; ERS marker) and Interleukin-6 (IL-6; inflammation marker).Results GRP78 was associated with LDV in both multivariate models (β = 22.23 [4.08;40.38]; p = 0.0179, β = 20.47 [0.74;40.20]; p = 0.0423) but not with organ failure (SOFA score) at admission (r = 0.03 [-0.22;0.28]; p = 0.2559). GRP78 was lower among ICU survivors (1539.4 [1139.2;1941.1] vs. 1714.2 [1555.2;2579.1] pg/mL. respectively; p = 0.0297). IL-6 was associated with SOFA score at admission in both multivariate models (β = 136.60 [65.50;207.70]; p = 0.0003, β = 193.70 [116.60;270.90]; p < 0.0001) but not with LDV (r = 0.13 [-0.14;0.39]; p = 0.3219). IL-6 was no different between ICU survivors and non-survivors (12.2 [6.0;43.7] vs. 30.4 [12.9;69.7] pg/ml. respectively; p = 0.1857). There was no correlation between GRP78 and IL-6 plasma levels (r = 0.13 [-0.13;0.37]; p = 0.3106).Conclusion Among severe COVID-19 patients, ERS was associated with LDV but not with systemic inflammation, while systemic inflammation was associated with organ failure but not with LDV.