Cochrane · systematic review · CD015201
Obesity as an independent risk factor for COVID‐19 severity and mortality
Tadayon Najafabadi, B, Rayner, DG, Shokraee, K, et al. · Cochrane Database of Systematic Reviews · 2023 · Cochrane Library
Metabolic and Endocrine DisordersAMSTAR 2: not assessed
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
43
current version
GRADE rated
26
No studies
17
Included studies
NR
No studies 17 · 39.5%Ungraded 0 · 0%Very low 0 · 0%Low 11 · 25.6%Moderate 9 · 20.9%High 6 · 14%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Questions and results
Obesity Class I compared to Normal Weight or Non‐Obese for Adults with COVID‐19
Population: Adults with COVID‐19
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
OutcomesTime frame of absolute effects Obesity Class I vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Mortality(in‐hospital) Obesity Class I vs Normal Weight or Non‐Obese | Odds Ratio 1.04 | 15 studies · 335209 participants | High |
Mechanical ventilation(in‐hospital) Obesity Class I vs Normal Weight or Non‐Obese | Odds Ratio 1.38 | 10 studies · 187895 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency |
ICU admission(in‐hospital) Obesity Class I vs Normal Weight or Non‐Obese | Odds Ratio 1.36 | 7 studies · 162741 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency |
Hospitalisation(30‐days, community) Obesity Class I vs Normal Weight or Non‐Obese | Odds Ratio 0.96 | 5 studies · 515155 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency |
Severe COVID‐19(in‐hospital) Obesity Class I vs Normal Weight or Non‐Obese | Odds Ratio 1.48 | 3 studies · 1040 participants | Low Downgraded: risk of bias, imprecision, inconsistency |
Pneumonia  Obesity Class I vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
 Obesity Class I vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Obesity Class II compared to Normal Weight or Non‐Obese for Adults with COVID‐19
Population: Adults with COVID‐19
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
OutcomesTime frame of absolute effects Obesity Class II vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Mortality(in‐hospital) Obesity Class II vs Normal Weight or Non‐Obese | Odds Ratio 1.16 | 11 studies · 317925 participants | High |
Mechanical ventilation(in‐hospital) Obesity Class II vs Normal Weight or Non‐Obese | Odds Ratio 1.67 | 6 studies · 171149 participants | High |
ICU admission(in‐hospital) Obesity Class II vs Normal Weight or Non‐Obese | Odds Ratio 1.02 | 4 studies · 157665 participants | Low Downgraded: risk of bias, imprecision, inconsistency |
Hospitalisation(30‐days, community) Obesity Class II vs Normal Weight or Non‐Obese | Odds Ratio 1.04 | 3 studies · 293707 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency |
Severe COVID Obesity Class II vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Pneumonia Obesity Class II vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
 Obesity Class II vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Obesity Class III compared to Normal BMI, Non‐obese, or BMI < 40 for Adults with COVID‐19
Population: Adults with COVID‐19
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
OutcomesTime frame of absolute effects Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | no estimate extracted | NR | No studies |
Mortality(in‐hospital) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 1.67 | 19 studies · 354967 participants | Low Downgraded: risk of bias, imprecision, inconsistency, publication bias |
Mechanical ventilation(in‐hospital) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 2.17 | 11 studies · 174520 participants | High |
ICU admission (adjusted for at least DM, HTN, cardiovascular disease, age, and sex)(in‐hospital) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 1.2 | 3 studies · 155405 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency, publication bias |
Hospitalisation (adjusted for DM, HTN, cardiovascular disease, age, and sex)(30‐days, community) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 1.35 | 4 studies · 293004 participants | Low Downgraded: risk of bias, imprecision, inconsistency, publication bias |
ICU admission (in‐hospital) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 2.26 | 7 studies · 15691 participants | Low Downgraded: risk of bias, imprecision, inconsistency, publication bias |
Hospitalisation (30‐days, community) Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | Odds Ratio 1.77 | 7 studies · 747176 participants | Low Downgraded: risk of bias, imprecision, inconsistency, publication bias |
Severe COVID Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | no estimate extracted | NR | No studies |
.Pneumonia Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | no estimate extracted | NR | No studies |
 Obesity Class III vs Normal BMI, Non‐obese, or BMI < 40 | no estimate extracted | NR | No studies |
Obesity (Unclassified) compared to Normal Weight or Non‐Obese for Adults with COVID‐19
Population: Adults with COVID‐19
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
OutcomesTime frame of absolute effects Obesity (Unclassified) vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Mortality(in‐hospital) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.35 | 54 studies · 1307520 participants | Low Downgraded: imprecision, inconsistency, publication bias |
Mechanical ventilation(in‐hospital) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.69 | 21 studies · 62348 participants | Low Downgraded: imprecision, inconsistency, publication bias |
ICU admission(in‐hospital) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.86 | 21 studies · 70529 participants | Moderate Downgraded: imprecision, inconsistency, publication bias |
Hospitalisation (adjusted for age, sex, DM, HTN, and cardiovascular disease)(30 days, community) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.31 | 14 studies · 510405 participants | Moderate Downgraded: imprecision, inconsistency, publication bias |
Severe COVID(30‐days, community) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.94 | 19 studies · 878804 participants | High |
Pneumonia(30‐days, community) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.44 | 5 studies · 35924 participants | Moderate Downgraded: imprecision, inconsistency, publication bias |
Hospitalisation (30 days, community) Obesity (Unclassified) vs Normal Weight or Non‐Obese | Odds Ratio 1.31 | 20 studies · 515517 participants | Low Downgraded: imprecision, inconsistency, publication bias |
 Obesity (Unclassified) vs Normal Weight or Non‐Obese | no estimate extracted | NR | No studies |
Every 5 units (kg/m2) increase in BMI compared to N/A for Adults with COVID
Population: Adults with COVID
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
OutcomesTime frame of absolute effects Every 5 units (kg/m2) increase in BMI vs N/A | no estimate extracted | NR | No studies |
Mortality(in‐hospital) Every 5 units (kg/m2) increase in BMI vs N/A | Odds Ratio 1.16 | 10 studies · 6937150 participants | High |
Mechanical ventilation(in‐hospital) Every 5 units (kg/m2) increase in BMI vs N/A | Odds Ratio 1.28 | 2 studies · 13527 participants | Moderate Downgraded: risk of bias, imprecision, inconsistency |
ICU admission Every 5 units (kg/m2) increase in BMI vs N/A | no estimate extracted | NR | No studies |
Hospitalisation(30 days, community) Every 5 units (kg/m2) increase in BMI vs N/A | Odds Ratio 1.17 | 3 studies · 6911600 participants | Low Downgraded: risk of bias, imprecision, inconsistency |
Severe COVID (community) Every 5 units (kg/m2) increase in BMI vs N/A | Odds Ratio 1.94 | 5 studies · 1041 participants | Low Downgraded: risk of bias, imprecision, inconsistency |
Pneumonia Every 5 units (kg/m2) increase in BMI vs N/A | no estimate extracted | NR | No studies |
 Every 5 units (kg/m2) increase in BMI vs N/A | no estimate extracted | NR | No studies |