COVID Patients With High BMI Face Longer ICU Stay and Increased Risk of Death

High BMI independently associated with death and longer ICU stay for COVID patients.

In a large Swedish cohort study, obese patients (BMI >35 kg/m2) were twice as likely to have an extended ICU stay or to die.

In patients with COVID-19, a high body mass index (BMI) is associated with an increased risk of death and prolonged stay in the intensive care unit (ICU), according to a new study published this week in the open-access journal PLOS ONE. by Lovisa Sjögren of Sahlgrenska Academy at the University of Gothenburg, Sweden, and colleagues.

Previous studies have shown that a high BMI is a risk factor for severe COVID-19. Obesity increases the risk of co-morbidities such as type 2 diabetes and hypertension, and has been shown to increase the need for mechanical ventilation associated with other infectious respiratory diseases, such as the flu and pneumonia.

Sahlgrenska Hospital and the Sahlgrenska Academy. Credit: Johan Winborg, CC-BY 4.0

In the new study, Sjögren and colleagues analyzed data from 1,649 COVID-19 patients from the Swedish Intensive Care Registry, a national quality registry that includes all ICUs in Sweden. The patients included in the study were admitted to ICUs during the first wave of the COVID-19 pandemic, between March 6 and August 30, 2020, 96% had a positive PCR test for the SARS-CoV-2 virus or a clinical diagnosis of COVID-19, were all over 18 years of age and had current data on weight and height available.

A majority of the study cohort had a high BMI; 78.3% were overweight or obese. There was a significant association between increasing BMI and the composite outcome of death during intensive care or an ICU stay longer than 14 days in survivors (OR per SD increase: 1.29 95%CI 1.16-1.43 adjusted for age and sex ). Individuals with a BMI of 35 kg/m2 or more were twice as likely to have any of the outcomes of death or long-term ICU stay, adjusted for age and gender. In addition, this association persisted after adjusting for the presence of cardiovascular disease, hypertension, diabetes mellitus, liver or kidney disease, as well as after adjusting for disease severity at ICU admission (OR 2.02 [1.39-2.94] versus normal weight). The authors conclude that obesity is an independent risk factor for serious consequences of intensive care in patients with COVID-19 and propose to include BMI in the severity score for COVID-19 ICU patients.

The authors add: “In this large cohort of Swedish ICU patients with COVID-19, a high BMI was associated with an increased risk of death and longer ICU stay. Based on our findings, we suggest that obese individuals should be monitored more closely when hospitalized for COVID-19.”

Reference: “Impact of obesity on intensive care outcomes in patients with COVID-19 in Sweden – a cohort study” October 13, 2021, PLoS ONE.
DOI: 10.1371/journaal.pone.0257891