Impact of obesity on intensive care outcomes in patients with COVID-19 in Sweden-A cohort study

PLoS One. 2021 Oct 13;16(10):e0257891. doi: 10.1371/journal.pone.0257891. eCollection 2021.

Abstract

Background: Previous studies have shown that a high body mass index (BMI) is a risk factor for severe COVID-19. The aim of the present study was to assess whether a high BMI affects the risk of death or prolonged length of stay (LOS) in patients with COVID-19 during intensive care in Sweden.

Methods and findings: In this observational, register-based study, we included patients with COVID-19 from the Swedish Intensive Care Registry admitted to intensive care units (ICUs) in Sweden. Outcomes assessed were death during intensive care and ICU LOS ≥14 days. We used logistic regression models to evaluate the association (odds ratio [OR] and 95% confidence interval [CI]) between BMI and the outcomes. Valid weight and height information could be retrieved in 1,649 patients (1,227 (74.4%) males) with COVID-19. We found a significant association between BMI and the risk of the composite outcome death or LOS ≥14 days in survivors (OR per standard deviation [SD] increase 1.30, 95%CI 1.16-1.44, adjusted for sex, age and comorbidities), and this association remained after further adjustment for severity of illness (simplified acute physiology score; SAPS3) at ICU admission (OR 1.30 per SD, 95%CI 1.17-1.45). Individuals with a BMI ≥ 35 kg/m2 had a doubled risk of the composite outcome. A high BMI was also associated with death during intensive care and a prolonged LOS in survivors assessed as separate outcomes. The main limitations were the restriction to the first wave of the pandemic, and the lack of information on socioeconomic status as well as smoking.

Conclusions: In this large cohort of Swedish ICU patients with COVID-19, a high BMI was associated with increasing risk of death and prolonged length of stay in the ICU. Based on our findings, we suggest that individuals with obesity should be more closely monitored when hospitalized for COVID-19.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Mass Index
  • COVID-19 / complications
  • COVID-19 / diagnosis*
  • COVID-19 / virology
  • Cohort Studies
  • Critical Care
  • Female
  • Humans
  • Intensive Care Units
  • Length of Stay
  • Male
  • Middle Aged
  • Obesity / complications
  • Obesity / pathology*
  • Odds Ratio
  • Registries
  • Risk Factors
  • SARS-CoV-2 / isolation & purification
  • SARS-CoV-2 / metabolism
  • Sweden

Grants and funding

JMK has support from the Swedish Research Council (2018-02597), the Heart-Lung Foundation (20190624; 20190404)), and by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF-agreement (ALFGBG-723791). LS received support from the Regional ALF-agreement at Queen Silvia Children´s Hospital. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.