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BMI and Risk for Severe COVID-19 Among Veterans Health Administration Patients
Jessica Y Breland1, Michelle S Wong2, W Neil Steers2,3
1VA Health Services Research and Development Center for Innovation to Implementation, VA Palo Alto Health Care System, Menlo Park, California, USA.
Insights
Body Mass Index (BMI) is linked to severe COVID-19 outcomes in a J-curve pattern. Higher BMI increases hospitalization and mortality risk, especially for those under 75 with obesity.
Area of Science:
- Public Health
- Epidemiology
- Medical Research
Background:
- Obesity is a growing public health concern.
- Understanding the impact of Body Mass Index (BMI) on severe COVID-19 outcomes is crucial.
Purpose of the Study:
- To assess the association between BMI and severe COVID-19 outcomes (hospitalization, ICU admission, mortality).
- To investigate if these associations differ by age group.
Main Methods:
- Analysis of a cohort of 9,347 COVID-19 positive patients from the Veterans Health Administration (VHA).
- Piecewise logistic regression models with restricted cubic splines were used to analyze BMI-outcome associations.
- Adjustments were made for age, sex, comorbidities, and other demographic factors.
Main Results:
- A nonlinear J-curve association was observed between BMI and hospitalization/mortality.
- Increased BMI (30-39) was linked to higher odds of hospitalization, ICU admission, and mortality.
- Lower BMI (23-30) showed decreased odds of hospitalization and mortality.
- Patients under 75 with BMI 30-39 had increased mortality odds with rising BMI.
Conclusions:
- Severe COVID-19 outcomes increase with BMI, particularly for individuals with obesity.
- Public health messaging should highlight obesity-related risks for COVID-19, especially for those under 75.
- Further research is needed to explore this nonlinear BMI-COVID-19 relationship.
Objective:
The purpose of this study was to assess associations between BMI and severe coronavirus disease 2019 (COVID-19) outcomes: hospitalization, intensive care unit (ICU) admission, and mortality. A secondary aim was to investigate whether associations varied by age.
Methods:
The cohort comprised patients in the Veterans Health Administration (VHA) who tested positive for COVID-19 (N = 9,347). For each outcome, we fit piecewise logistic regression models with restricted cubic splines (knots at BMI of 23, 30, and 39), adjusting for age, sex, comorbidities, VHA nursing home residence, and race/ethnicity. Supplemental analyses included age-by-BMI interaction terms (α = 0.05).
Results:
We found evidence of a nonlinear J-curve association between BMI and likelihood of hospitalization and mortality. BMI was associated with increased odds for hospitalization, ICU admission, and mortality among patients with BMI 30 to 39 but decreased odds of hospitalization and mortality for patients with BMI 23 to 30. Patients under age 75 with BMI between 30 and 39 had increased odds for mortality with increasing BMI.
Conclusions:
Odds for severe outcomes with COVID-19 infection increased with increasing BMI for people with, but not without, obesity. This nonlinear relationship should be tested in future research. COVID-19 public health messages in VHA, and broadly, should incorporate information about risks associated with all classes of obesity, particularly for those under age 75.
