(P31-048-23) Association Between BMI, In-Hospital Mortality and Need for Mechanical Ventilation in Patients With COVID-19

Objectives: To examine the associations between overweight and obesity (BMI ≥ 25.0 kg/m²), in-hospital mortality, and the need for mechanical ventilation in adults diagnosed with COVID-19. 

Methods: A literature search was conducted using PubMed and CINAHL. Studies inclusion criteria were diagnosis of COVID-19 using PCR assay, adult patient aged 18 years and older, BMI weight status classified according to the WHO guidelines as underweight ( < 18.5 kg/m²), normal weight (18.5–24.9 kg/m²), overweight (25.0–29.9 kg/m²), obesity class I (30.0–34.9 kg/m²), obesity class II (35.0–39.9 kg/m²), and obesity class III (≥40.0 kg/m²), and observational study design. The search resulted in 360 primary research articles. Five studies met the inclusion criteria.

Results: Five retrospective cohort studies (N = 21,321) examined the association of BMI with in-hospital mortality (n = 4,605). Compared to non-obese BMIs, all five studies found that a BMI ≥ 30 kg/m² was a significant predictor of in-hospital mortality in patients with COVID-19 (OR=1.48, 95% CI=1.27-1.72; HR=1.26, 95% CI=1.0-1.6; HR= 1.1, 95% CI=0.9-1.4; OR= 1.7, 95% CI=1.1-2.8; and RR= 1.3, 95% CI=1.0-1.7).  Four out of five studies measured the association between the need for mechanical ventilation and BMI (n = 3,970). In four studies, class III obesity (BMI ≥ 40 kg/m²) was associated with an increased risk of mechanical ventilation compared to non-obese BMI groups (OR=2.31, 95% CI=1.88-2.85; HR= 2.08, 95% CI=1.68-2.58; HR= 1.6, 95% CI=1.1-2.1; and RR (risk ratio) = 2.4, 95% CI= 1.5-4.0). Measures of associations in all five studies were adjusted for age, sex, and comorbidities including hypertension, diabetes mellitus, and cancer.

Conclusions: Obesity classes I, II, and III were associated with an increased risk of in-hospital mortality, whereas only obesity class III was associated with an increased need for mechanical ventilation. This suggests that hospitalized patients who are overweight or obese and diagnosed with COVID-19 may necessitate higher levels of care and increased allocation of treatment resources. Additionally, RDNs should closely monitor the nutrition status of patients with overweight/obesity and those admitted with COVID-19 as those patients are at the highest risk for requiring mechanical ventilation and nutrition support.

Funding Sources: None