Body mass index associated with severity and mortality of patients with coronavirus disease 2019: A systematic review and meta-analysis

Abstract Background As an important indicator to measure obesity or underweight, body mass index (BMI) can be used to assess the potential risk for various diseases. The present study systematically examined the relationship between BMI and severity and mortality of patients with coronavirus disease 2019 (COVID-19). Methods We systematically searched PubMed, Embase, Cochrane, and China National Knowledge Infrastructure (CNKI) for studies published as of September 3, 2020 and extracted the relevant data of research endpoints in each study. Results This study included 16 studies with 6087 patients. This study observed a significant increase in BMI on admission in patients with severe COVID-19 compared with those with non-severe COVID-19 (Mean difference [MD] = 1.95, 95% confidence interval [CI], 1.52 − 2.37, I2 = 33%, P < 0.00001). A significant increase in BMI on admission was observed in patients who died from COVID-19 compared with (MD = 3.01, 95% CI: 1.83 to 4.19, I2 = 0%, P < 0.00001). In the intensive care unit (ICU) or geriatric ward, the study observed a significant decrease in BMI in the non-survivor group compared with the survivor group (MD = -1.61, 95% CI: -3.07 to -0.16, I2 = 72%, P = 0.03). Conclusions Higher BMI on admission is associated with severity and mortality of patients with COVID-19, but lower BMI is associated with mortality of patients with COVID-19 in the ICU or geriatric ward. Thus, we strongly recommend that clinicians should closely monitor the BMI of patients with COVID-19, especially those from the ICU or geriatric ward.