Table 1.
Main characteristics of the included studies.
| References | Study design | Number of patients with COVID-19 | Exposure | Outcomes | Main results |
|---|---|---|---|---|---|
| Argenziano et al. (24) | Cross-sectional | 1000 | Mean BMI kg/m2 |
Level of hospital care | Mean BMI of admitted ICU patients was significantly higher than BMI of admitted patients in all other levels of care (31.2 ± 8.0 vs. 29.9 ±7.24 kg/m2) (DM 1.30, 95% CI 95% 0.15–2.45; p = 0.03) |
| Bello-Chavolla et al. (25) | Cross-sectional | 8261 | BMI > 30 kg/m2
Age > 65 years |
Mortality Hospitalization Pneumonia ICU admission Invasive mechanical ventilation |
Compared to non-obese, obese patients had a significantly increased risk of: • Mortality (13.6 vs. 7.1%, p < 0.001; HR 7.56 95%CI 5.79–9.87) • Hospitalization (47.3 vs. 34.4%, p < 0.001) • Pneumonia (36.4 vs. 25.9%, p < 0.001) • ICU admission (7.2 vs. 4.2%, p = 0.034) • Invasive ventilation (6.9 vs. 4%, p = 0.029) |
| Cummings et al. (18) | Prospective cohort | 257 | Severe obesity (BMI ≥ 35 kg/m2) | Rate of in-hospital death | No difference between obese and non-obese patients in mortality (HR 0.94, 95% CI 0.55–1.77) |
| Lighter et al. (20) | Retrospective cohort | 3,615 | BMI < 30 vs. BMI 30–34 and BMI ≥ 35 kg/m2 |
Age (>60 and < 60 years) Hospital admission |
Age > 60 years: Compared to non-obese (BMI < 30), there was no difference between groups in: • Admission to acute care: BMI 30–34: RR 0.9, 95% CI 0.6–1.2, p = 0.39 BMI ≥35: RR 0.9, 95% CI 0.6–1.3, p = 0.59 • Admission to ICU: BMI 30–34: RR 1.1, 95% CI 0.8−1.7, p = 0.57 BMI ≥35: RR 1.5, 95% CI 0.9–2.3, p = 0.10 Age < 60 years: Compared to non-obese (BMI < 30), obese patients had more: • Admission to acute care: BMI 30–34: RR 2.0, 95% CI 1.6–2.6, p < 0.0001 BMI ≥35: RR 2.2, 95% CI 1.7–2.9, p < 0.0001 • Admission to ICU: BMI 30–34: RR 1.8, 95% CI 1.2–2.7, p = 0.006 BMI ≥35: RR 3.6, 95% CI 2.5–5.3, p < 0.0001. |
| Liu et al. (21) | Retrospective cohort | 30 | BMI (mean, SD) | COVID-19 severity (mild vs. severe) | Severe COVID patients had a significantly higher mean BMI (27.0 ± 2.5) than mild patients (22.0 ± 1.3) (p < 0.001). |
| Peng et al. (22) | Retrospective cohort | 112 | BMI ≥ 25 (obese plus overweight) vs. BMI < 24 kg/m2 (eutrophic or lean) | Mortality | Obese patients had a significant increased risk of mortality comparing to non-obese (18.92 vs. 88.24%, p < 0.001); Mean BMI of the critical group (ICU need) was significantly higher than the general group (n = 16 vs. 96; p = 0.003). |
| Petrilli et al. (26) | Cross-sectional | 4,103 | BMI < 30 vs. BMI 30–40 and BMI >40 kg/m2 |
Hospitalization | •Non-hospitalized group: BMI 30–40: 12.2% (256 patients) BMI >40: 2.3% (48 patients) • Hospitalized group: BMI 30–40: 33.0% (659 patients) BMI >40: 6.9% (137 patients) BMI >40 was significantly associated with hospitalization when compared to BMI < 30 (OR 6.2, 95% CI 4.2–9.3) |
| Simonnet et al. (23) | Retrospective cohort | 124 | BMI categories: 18.5 to < 25; 25 to < 30; 30 to < 3; ≥35 kg/m2 |
Invasive mechanical ventilation | Obese patients (BMI ≥ 35) had a significant increased risk of invasive ventilation need, comparing to non-obese (BMI < 25) (OR 7.36, 95% CI 1.63–33.14, p = 0.021) |
| Zheng et al. (19) |
Prospective cohort | 66 (with metabolic associated fatty liver disease) |
BMI > 25 kg/m2 | COVID-19 severity |
Severe patients had a significantly higher proportion of obese than non-severe (89.5 vs. 59.6%, p = 0.021). Obese patients with metabolic associated fatty liver diseases had a significantly increased risk of severe COVID-19 (OR 6.32, 95% CI 1.16–34.54, p = 0.033) |
n, number of participants; BMI, body mass index; ICU, Intensive care unit; SD, Standard deviation; HR, Hazard ratio.