Clinical, Immunological, and Virological SARS-CoV-2 Phenotypes in Obese and Nonobese Military Health System Beneficiaries
Authors: Epsi Nusrat J , Richard Stephanie A , Laing Eric D , Fries Anthony C , Millar Eugene , Simons Mark P , English Caroline , Colombo Christopher J , Colombo Rhonda E , Lindholm David A , Ganesan Anuradha , Maves Ryan C , Huprikar Nikhil , Larson Derek , Mende Katrin , Chi Sharon W , Madar Cristian , Lalani Tahaniyat , Broder Christopher C , Tribble David , Agan Brian K , Burgess Timothy H , Pollett Simon D ,   EPICC COVID-19 Cohort Study Group, Cowden J , Lindholm D , Markelz A , Mende K , Merritt T , Walter R , Wellington T , Darnall Carl R , Bazan S , Brandon L , Dimascio-Johnson N , Gallagher K , Larson D , Jackson Henry M , Blair P , Clark D , Chambers S , Colombo C , Colombo R , Conlon C , Everson K , Faestel P , Ferguson T , Gordon L , Grogan S , Lis S , Mount C , Musfeldt D , Sainato R , Schofield C , Skinner C , Stein M , Switzer M , Timlin M , Wood S , Atwood G , Carpenter R , Eickhoff C , Kronmann K , Lalani T , Lee T , Warkentien T , Arnold J , Berjohn C , Cammarata S , Husain S , Kirkland N , Lane A , Maves R , Parrish J , Utz G , Chi S , Filan E , Fong K , Horseman T , Jones M , Kanis A , Kayatani A , Londeree W , Madar C , Masel J , McMahon M , Murphy G , Ngauy V , Schoenman E , Uyehara C , Villacorta Lyew R , Agan B , Broder C , Burgess T , Byrne C , Chung K , Coles C , English C , Hickey P , Laing E , Livezey J , Malloy A , Oliver T , Parmelee E , Pollett S , Richard S , Rozman J , Rusiecki J , Sanchez M , Scher A , Simons M , Snow A , Tribble D , Fries A , Ganesan A , Gunasekera D , Huprikar N , Oyeneyin M , Banda M , Davis B , Hunter T , Ikpekpe-Magege O , Kemp S , Mody R , Resendez R , Wiggins M 
Published: July 2021

Abstract

Background
The mechanisms underlying the association between obesity and coronavirus disease 2019 (COVID-19) severity remain unclear. After verifying that obesity was a correlate of severe COVID-19 in US Military Health System (MHS) beneficiaries, we compared immunological and virological phenotypes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in both obese and nonobese participants.

Methods
COVID-19–infected MHS beneficiaries were enrolled, and anthropometric, clinical, and demographic data were collected. We compared the SARS-CoV-2 peak IgG humoral response and reverse-transcription polymerase chain reaction viral load in obese and nonobese patients, stratified by hospitalization, utilizing logistic regression models.

Results
Data from 511 COVID-19 patients were analyzed, among whom 24% were obese and 14% severely obese. Obesity was independently associated with hospitalization (adjusted odds ratio [aOR], 1.91; 95% confidence interval [CI], 1.15–3.18) and need for oxygen therapy (aOR, 3.39; 95% CI, 1.61–7.11). In outpatients, severely obese had a log10 (1.89) higher nucleocapsid (N1) genome equivalents (GE)/reaction and log10 (2.62) higher N2 GE/reaction than nonobese (P = 0.03 and P &lt; .001, respectively). We noted a correlation between body mass index and peak anti-spike protein IgG in inpatients and outpatients (coefficient = 5.48, P &lt; .001).

Conclusions
Obesity is a strong correlate of COVID-19 severity in MHS beneficiaries. These findings offer new pathophysiological insights into the relationship between obesity and COVID-19 severity.