The negative impact of obesity on the occurrence and prognosis of the 2019 novel coronavirus (COVID-19) disease: a systematic review and meta-analysis

PURPOSE: The 2019 novel coronavirus (COVID-19) is an emerging pandemic, with a disease course varying from asymptomatic infection to critical disease resulting to death. Recognition of prognostic factors is essential because of its growing prevalence and high clinical costs. This meta-analysis aimed to evaluate the global prevalence of obesity in COVID-19 patients and to investigate whether obesity is a risk factor for the COVID-19, COVID-19 severity, and its poor clinical outcomes including hospitalization, intensive care unit (ICU) admission, need for mechanical ventilation, and mortality. METHODS: The study protocol was registered in PROSPERO (CRD42020203386). A systematic search of Scopus, Medline, and Web of Sciences was conducted from 31 December 2019 to 1 June 2020 to find pertinent studies. After selection, 54 studies from 10 different countries were included in the quantitative analyses. Pooled odds ratios (OR) with 95% confidence intervals (CIs) were calculated to assess the associations. RESULTS: The prevalence of obesity was 33% (95% CI 30.0%–35.0%) among patients with COVID-19. Obesity was significantly associated with susceptibility to COVID-19 (OR = 2.42, 95% CI 1.58–3.70; moderate certainty) and COVID-19 severity (OR = 1.62, 95% CI 1.48–1.76; low certainty). Furthermore, obesity was a significant risk factor for hospitalization (OR = 1.75, 95% CI 1.47–2.09; very low certainty), mechanical ventilation (OR = 2.24, 95% CI 1.70–2.94; low certainty), intensive care unit (ICU) admission (OR = 1.75, 95% CI 1.38–2.22; low certainty), and death (OR = 1.23, 95% CI 1.06–1.41; low certainty) in COVID-19 patients. In the subgroup analyses, these associations were supported by the majority of subgroups. CONCLUSION: Obesity is associated with COVID-19, need for hospitalization, mechanical ventilation, ICU admission, and death due to COVID-19. LEVEL OF EVIDENCE: Level I, systematic reviews and meta-analyses. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40519-021-01269-3.