Association between categorical variables and mortality, severe disease, or both in patients with COVID-19
| Risk Factor | Studies | Patients | RR (95% CI) |
|---|---|---|---|
| Outcome = Death | |||
| Age <39 to 40 years | 1 | 274 | 0.01 (0.00–0.21) |
| Age <45 years | 1 | 107 | 0.21 (0.06–0.79) |
| Age >45 years | 1 | 107 | 1.79 (1.38–2.32) |
| Age >75 years | 1 | 107 | 10.42 (3.58–30.33) |
| Age ≥40 years | 1 | 274 | 1.49 (1.33–1.66) |
| Age ≥60 to 65 years | 3 | 483 | 2.62 (1.91–3.58) |
| Age 40–60 years | 1 | 274 | 0.55 (0.34–0.89) |
| Age 45–59 years | 1 | 107 | 0.19 (0.03–1.34) |
| Age 60–75 years | 1 | 107 | 2.03 (0.97–4.23) |
| Any comorbidity | 1 | 692 | 2.99 (2.37–3.77) |
| Chronic kidney disease | 5 | 1562 | 5.11 (2.18–11.98) |
| COPD | 9 | 2213 | 3.79 (2.51–5.72) |
| Coronary heart disease | 9 | 2213 | 5.27 (2.89–9.58) |
| Cough | 5 | 1366 | 1.02 (0.93–1.13) |
| CRP >100 mg/L | 2 | 243 | 4.16 (2.71–6.37) |
| CRP ≥3 mg/L | 1 | 102 | 1.19 (1.04–1.36) |
| CRP increased | 1 | 581 | 1.42 (1.29–1.55) |
| D-dimer ≤0.5 mg/L | 4 | 718 | 0.19 (0.12–0.30) |
| D-dimer >21 mg/L | 1 | 247 | 17.53 (5.54–55.49) |
| D-dimer ≥0.5 mg/L | 3 | 569 | 1.54 (1.32–1.80) |
| D-dimer ≥1.0 mg/L | 4 | 718 | 2.56 (2.10–3.13) |
| D-dimer 0.5–1.0 mg/L | 4 | 718 | 0.45 (0.31–0.64) |
| D-dimer increased | 1 | 371 | 2.63 (1.91–3.63) |
| Diabetes mellitus | 9 | 2213 | 2.15 (1.46–3.15) |
| Dyspnea | 3 | 1073 | 3.47 (1.67–7.18) |
| Fever | 6 | 1530 | 1.10 (0.95–1.28) |
| Heart rate >100 | 1 | 274 | 1.66 (1.23–2.25) |
| Heart rate ≥125 | 1 | 191 | 12.55 (0.61–257.13) |
| Hypertension | 9 | 2213 | 2.34 (1.80–3.05) |
| LDH increased | 3 | 831 | 5.16 (0.72–37.09) |
| Lymphocyte count <0.5 | 1 | 274 | 7.84 (3.84–16.00) |
| Lymphocyte count <0.8 to 1.1 | 4 | 841 | 2.07 (1.51–2.84) |
| Lymphocyte count ≥1 | 1 | 274 | 0.17 (0.09–0.31) |
| Lymphocyte count 0.5–0.8 | 1 | 274 | 1.53 (1.07–2.19) |
| Lymphocyte count 0.8–1 | 1 | 274 | 0.81 (0.46–1.43) |
| Lymphocytes decreased | 1 | 547 | 2.10 (1.87–2.36) |
| Male sex | 9 | 2213 | 1.24 (1.08–1.43) |
| Neutrophil count >6.3 | 1 | 274 | 6.29 (3.94–10.04) |
| Neutrophils increased | 1 | 544 | 6.12 (3.86–9.70) |
| Oxygen saturation <90 to 93 | 3 | 718 | 6.07 (4.27–8.63) |
| Procalcitonin <0.05 ng/mL | 1 | 236 | 0.02 (0.00–0.15) |
| Procalcitonin <0.1 ng/mL | 1 | 164 | 0.44 (0.31–0.64) |
| Procalcitonin >0.05 ng/mL | 1 | 102 | 1.79 (1.45–2.22) |
| Procalcitonin ≥0.1 to 0.25 ng/mL | 1 | 164 | 2.53 (1.34–4.79) |
| Procalcitonin ≥0.25 to 0.5 ng/mL | 4 | 728 | 9.59 (3.71–24.82) |
| Procalcitonin ≥2.0 ng/mL | 1 | 236 | 24.71 (1.44–423.13) |
| Procalcitonin 0.05–0.5 ng/mL | 1 | 236 | 1.31 (1.04–1.65) |
| Procalcitonin 0.5–2.0 ng/mL | 1 | 236 | 13.13 (4.10–42.04) |
| Procalcitonin increased | 1 | 455 | 1.48 (1.18–1.85) |
| Respiratory rate <24 | 1 | 274 | 0.48 (0.38–0.60) |
| Respiratory rate >20 to 30 | 4 | 841 | 3.80 (2.13–6.78) |
| Respiratory rate 24–30 | 1 | 274 | 3.02 (1.79–5.10) |
| SBP <90 mm Hg | 2 | 274 | 5.70 (1.23–26.34) |
| SBP ≥140 mm Hg | 1 | 274 | 2.16 (1.49–3.12) |
| SBP 90–140 mm Hg | 1 | 274 | 0.62 (0.51–0.76) |
| Troponin >34.2 | 1 | 101 | 6.96 (2.61–17.17) |
| WBC < 3.5 to 4 | 3 | 567 | 0.34 (0.20–0.56) |
| WBC ≥4 | 3 | 567 | 1.07 (0.81–1.41) |
| WBC ≥9.5 to 10 | 3 | 567 | 5.73 (2.48–13.27) |
| WBC 4–10 | 3 | 567 | 0.65 (0.54–0.78) |
| WBC increased | 1 | 630 | 16.08 (9.05–28.58) |
| Outcome = severe disease or death | |||
| Age ≥40 years | 1 | 323 | 1.13 (1.07–1.19) |
| Age ≥60 to 65 years | 1 | 323 | 2.06 (1.56–2.74) |
| Chronic kidney disease | 1 | 1590 | 4.45 (1.76–11.29) |
| COPD | 2 | 1913 | 5.63 (1.07–29.69) |
| Coronary heart disease | 1 | 1590 | 3.15 (1.75–5.57) |
| Cough | 2 | 1821 | 1.06 (0.96–1.17) |
| CRP ≥3 mg/L | 1 | 306 | 1.13 (1.07–1.19) |
| Diabetes mellitus | 2 | 1913 | 3.24 (2.41–4.36) |
| Dyspnea | 2 | 1717 | 3.09 (2.59–3.68) |
| Fever | 2 | 1859 | 1.01 (0.96–1.07) |
| Hypertension | 2 | 1913 | 2.00 (1.06–3.78) |
| LDH increased | 1 | 87 | 3.32 (1.75–6.32) |
| Lymphocyte count <2.0 | 1 | 305 | 1.57 (1.33–1.84) |
| Male sex | 2 | 1901 | 1.19 (1.06–1.33) |
| Neutrophil count >7.5 | 1 | 305 | 3.02 (2.28–3.99) |
| WBC ≥9.5 to 10 | 1 | 305 | 9.14 (3.94–21.24) |
| Outcome = severe disease | |||
| Age <39 to 40 years | 1 | 198 | 0.29 (0.08–1.11) |
| Age >75 years | 1 | 2729 | 1.69 (1.49–1.93) |
| Age ≥40 years | 1 | 198 | 1.39 (1.15–1.68) |
| Age ≥50 years | 1 | 198 | 1.62 (1.23–2.14) |
| Age ≥60 to 65 years | 2 | 564 | 2.53 (1.89–3.40) |
| Age ≥70 years | 1 | 198 | 4.71 (2.33–9.53) |
| Age 40–49 years | 1 | 198 | 0.67 (0.17–2.61) |
| Age 50–59 years | 1 | 198 | 0.13 (0.01–2.11) |
| Age 60–69 years | 1 | 198 | 1.74 (0.90–3.33) |
| Asthma or COPD | 1 | 2729 | 1.05 (0.88–1.24) |
| Chronic kidney disease | 3 | 3516 | 3.02 (0.63–14.60) |
| COPD | 7 | 1033 | 2.47 (1.34–4.52) |
| Coronary heart disease | 9 | 4364 | 3.69 (1.75–7.77) |
| Cough | 9 | 1775 | 1.11 (0.87–1.42) |
| CRP >5 to 10 mg/L | 3 | 448 | 1.68 (1.47–1.93) |
| D-dimer ≥0.5 mg/L | 2 | 877 | 3.10 (1.45–6.64) |
| Diabetes mellitus | 11 | 4582 | 2.57 (1.59–4.17) |
| spnea | 7 | 1473 | 6.28 (3.10–12.74) |
| Fever | 10 | 4504 | 1.13 (1.05–1.22) |
| Heart rate ≥90 | 1 | 366 | 0.88 (0.43–1.79) |
| Hypertension | 11 | 4582 | 2.29 (1.61–3.26) |
| LDH increased | 1 | 110 | 2.65 (1.93–3.63) |
| Lymphocyte count <0.8 to 1.1 | 2 | 308 | 27.36 (0.96–778.27) |
| Lymphocyte count >3.2 | 1 | 198 | 0.13 (0.02–0.90) |
| Male sex | 11 | 4582 | 1.30 (1.11–1.53) |
| Neutrophil count <1.8 | 1 | 198 | 0.26 (0.02–4.12) |
| Neutrophil count >6.3 | 1 | 308 | 4.13 (2.31–7.37) |
| Oxygen saturation <88 | 1 | 2729 | 3.69 (3.06–4.46) |
| Oxygen saturation <96 | 1 | 366 | 1.39 (0.77–2.52) |
| Procalcitonin >0.05 ng/mL | 3 | 448 | 4.06 (0.65–25.29) |
| Respiratory rate >20 to 30 | 2 | 477 | 2.11 (0.20–22.05) |
| SBP ≥110 mm Hg | 1 | 366 | 1.07 (1.01–1.13) |
| WBC <3.5 to 4 | 1 | 198 | 0.67 (0.17–2.61) |
| WBC ≥9.5 to 10 | 2 | 308 | 5.52 (2.41–12.66) |
COPD = chronic obstructive pulmonary disease; RR, risk ratio; CI, confidence interval; CRP, c-reactive protein; LDH, lactate dehydrogenase; WBC, white blood count; SBP, systolic blood pressure.