Obesity is associated with poor outcomes, increased mortality, and increased rates of mechanical ventilation among patients hospitalized with COVID-19, according to study results published in Obesity Science & Practice.
Investigators assessed the effects of obesity on the outcomes of patients hospitalized with COVID-19.
Data were sourced from the National Inpatient Sample (NIS) 2020 database. Patients hospitalized with a principle diagnosis of COVID-19 according to International Classification of Disease, 10th revision, Clinical Modification codes were included in the analysis.
The primary study outcome was in-hospital mortality rates associated with different body mass index (BMI) classifications among COVID-19-related hospitalizations. Secondary outcomes included rates of mechanical ventilation, circulatory shock, thromboembolic events, and sepsis.
A total of 56,510 COVID-19-related hospitalizations were identified and included in the analysis.
Patients were classified according to BMI: 2740 patients had a BMI of 20.0 to 24.9 kg/m2 (defined as normal weight), 5281 had a BMI of 25.0 to 29.9 kg/m2 (defined as overweight), 13,681 had a BMI of 30.0 to 34.9 kg/m2 (defined as obesity class 1), 12,397 had a BMI of 35.0 to 39.9 kg/m2 (defined as obesity class 2), and 10,646 patients had a BMI of 40.0 to 44.9 kg/m2 (defined as obesity class 3).
Additionally, 5588 patients had a BMI of 45.0 to 49.9 kg/m2, 4468 had a BMI of 50.0 to 59.9 kg/m2, and 1709 patients had a BMI of 60.0 kg/m2 or higher.
After adjusting for comorbidities, patients with a BMI of 60 kg/m2 or higher had the highest mortality rate (odds ratio [OR], 2.66; 95% CI, 2.18-3.24) compared with patients classified as normal weight.
Patients with BMIs of 50.0 to 59.9 kg/m2 (OR, 1.72), 45.0 to 49.9 kg/m2 (OR, 1.51), and 40.0 to 44.9 kg/m2 (OR, 1.35) were also associated with a significant increase in mortality (P <.05). No significant differences in mortality rates were observed among the other BMI groups.
Higher incidences of in-hospital mortality, mechanical ventilation, shock, and sepsis were found among patients with increased BMI.
Specifically, the risk for circulatory shock was higher among patients with BMIs of 40.0 to 44.9 kg/m2 (OR, 1.40), 50.0 to 59.9 kg/m2 (OR, 1.60) and 60.0 kg/m2 or higher (OR, 2.14), compared with patients classified as having a normal BMI (P <.05).
There was no difference in risk for venous thromboembolism between the groups.
Higher BMI was also associated with an increased risk for sepsis, specifically among patients with BMIs of 40.0 to 44.9 kg/m2, 45.0 to 49.9 kg/m2, 50.0 to 59.9 kg/m2, and 60.0 kg/m2 or higher compared with patients classified as having a normal BMI (P <.05).
Limitations of this study included the potential risk for disease misclassification bias within the NIS database and the fact that different variants of COVID-19 were not considered.
“This study shows that increasing BMI is independently associated with poor outcomes in hospitalizations with COVID-19 infections. Further studies are needed to identify the underlying mechanism for this,” the study authors concluded.
Elkhapery A, Abdelhay A, Boppana HK, et al. Higher BMI is strongly linked to poor outcomes in adult COVID-19 hospitalizations: a National Inpatient Sample study. Obes Sci Pract. Published online July 1, 2023. doi:10.1002/osp4.692.