Table 1.
Result of systematic review (published and grey article).
| Source | Study design | Country | Population (n) | Median Age (IQR) | Sex | Used WHO interim guidance | Method of COVID-19 testing | Defined obesity | Other comorbidities measured | Findings | Definition of comparator |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Klang et al. | Retrospective cohort study | USA | 572 were young, and 2834 were old | NR | M/F | NR | Nasopharyngeal swab PCR test |
BMI | Coronary artery disease (CAD), Congestive heart failure (CHF), Hypertension (HTN), Diabetes mellitus, cancer, hyperlipidemia |
For both younger and the aged population who had a BMI above 40 kg/m2, was independently associated with mortality (p < 0.001) | BMI<30 |
| Hamer et al. | Cohort study | UK | 387,109 | NR | M/F | NR | RT-PCR | BMI | Diabetes, hypertension, cardiovascular disease | The relative risk ratio was higher among obese people with COVID-19 compared with a healthy weight. | BMI<25 |
| Simonnet et al. | Retrospective study | France | 124 | 60 (51–70) | M/F | Yes | Real-time reverse transcriptase–PCR | BMI | Diabetes, hypertension, dyslipidemia | Overweight and obesity were significantly more frequent among SARS-CoV-2 participants, and the requirement of IMV was significantly higher among obese and overweight participant | BMI<25 |
| Hu et al. | Retrospective study | China | 323 | 61 | M/F | Yes | RT-PCR, CT | BMI | Smoking, diabetes, critical disease designation, hypertension, WBC count, neutrophil count | BMI showed no significant effects on patients outcome (p > 0.05) | BMI<25 |
| Kalligeros et al. | Retrospective cohort study | USA | 103 | 60 (50–72) | M/F | NR | Reverse transcriptase–PCR assay | BMI | Hypertension, diabetes, heart disease | Admission to ICU and requirement of IMV were significantly associated with obesity and severe obesity | BMI<25 |
| McMichael et al. | Case report | USA | 167 | 72 | M/F | NR | rRT-PCR | NR | Hypertension, cardiac disease, renal disease, diabetes mellitus, cancer, liver disease, pulmonary disease | Most of the facility residents had chronic health conditions with obesity | NR |
| Richardson et al. | Case series | USA | 5700 | 63 (52–75) | M/F | NR | Nasopharyngeal swab PCR test |
BMI | Hypertension, diabetes, cancer, cardiovascular disease, liver disease, kidney disease, asthma | Obesity was identified as a common comorbidities | NR |
| Cai et al. | Case series | China | 383 | NR | M/F | Yes | Real-time reverse transcription PCR method | BMI | Diabetes, hypertension, cardiovascular disease, liver disease, cancer | The risk of developing severe COVID-19 was 1.84 times and 3.40 times higher among overweight and obese patients, respectively, especially in men. | BMI: 18.5–23.9 |
| Zheng et al. | NR | China | 214 | NR | M/F | NR | Real-time reverse transcription PCR method | BMI | T2D, hypertension, dyslipidemia | The presence of obesity with metabolic associated fatty liver disease was significantly associated with the increased risk of severe COVID-19 disease | BMI<25 |
| Deng et al. | Retrospective study | China | 112 | 65 (49–78) | M/F | Yes | RT-PCR test | BMI | Hypertension, diabetes, coronary heart disease, atrial fibrillation | Body mass index was not significantly associated with the disease severity of COVID-19 patients | NR |
| Petrilli et al. (unpublished) | Cross-sectional study | USA | 4103 | 52 (36–65) | M/F | NR | Real-time RT-PCR | BMI | Diabetes, cancer, coronary kidney disease, coronary artery disease | BMI of the patients was significantly associated with hospitalization. | BMI:<30 |
| Lighter et al. | Retrospective study | USA | 3615 | NR | M/F | NR | PCR | BMI | None | Higher BMI(≥30) and age<60 patients had high risk of admission in acute and critical care than lower BMI patients. | BMI<30 |