Subgroup analysis of the association of SARS-CoV-2 infection and severe COVID-19 outcomes associated with study patients who engaged in physical activities according to exercise guideline
| Subgroups | Event | Types of physical activity | |||
| Insufficient aerobic and muscle strengthening | Muscle strengthening only | Aerobic only | Aerobic and muscle strengthening | ||
| Age groups (years) | |||||
| 20–39 | COVID-19 | 1.0 (ref) | 1.43 (0.63 to 3.17) | 1.13 (0.55 to 2.27) | 0.99 (0.51 to 1.99) |
| 40–59 | COVID-19 | 1.0 (ref) | 1.04 (0.66 to 1.64) | 0.98 (0.76 to 1.27) | 0.85 (0.70 to 0.99) |
| ≥60 | COVID-19 | 1.0 (ref) | 0.83 (0.44 to 1.52) | 0.82 (0.61 to 1.10) | 0.77 (0.51 to 1.19) |
| Sex | |||||
| Male | COVID-19 | 1.0 (ref) | 1.02 (0.67 to 1.54) | 0.97 (0.73 to 1.29) | 0.81 (0.64 to 0.98) |
| Female | COVID-19 | 1.0 (ref) | 1.06 (0.62 to 1.79) | 0.90 (0.71 to 1.15) | 0.90 (0.66 to 1.28) |
| Smoking | |||||
| Never smoker | COVID-19 | 1.0 (ref) | 1.02 (0.67 to 1.54) | 0.97 (0.73 to 1.29) | 0.79 (0.64 to 0.99) |
| Ex-smoker | COVID-19 | 1.0 (ref) | 0.91 (0.45 to 1.84) | 0.92 (0.57 to 1.51) | 0.75 (0.45 to 1.31) |
| Current smoker | COVID-19 | 1.0 (ref) | 0.90 (0.27 to 2.93) | 1.28 (0.64 to 2.48) | 1.33 (0.58 to 3.00) |
| Charlson comorbidity index | |||||
| 0 | COVID-19 | 1.0 (ref) | 1.09 (0.72 to 1.61) | 0.99 (0.78 to 1.30) | 0.74 (0.58 to 0.94) |
| 1 | COVID-19 | 1.0 (ref) | 0.83 (0.34 to 2.03) | 1.16 (0.74 to 1.79) | 0.53 (0.16 to 1.09) |
| ≥2 | COVID-19 | 1.0 (ref) | 0.95 (0.54 to 1.11) | 0.78 (0.54 to 1.12) | 1.48 (0.94 to 2.31) |
| Age groups (years) | |||||
| 20–39 | Severe COVID-19† | 1.0 (ref) | 1.03 (0.62 to 1.76) | 0.66 (0.50 to 1.05) | 0.58 (0.25 to 1.30) |
| 40–59 | Severe COVID-19† | 1.0 (ref) | 1.09 (0.61 to 2.02) | 0.67 (0.43 to 1.19) | 0.48 (0.15 to 1.24) |
| ≥60 | Severe COVID-19† | 1.0 (ref) | 0.79 (0.26 to 3.05) | 0.58 (0.18 to 1.75) | 0.16 (0.02 to 0.96) |
| Sex | |||||
| Male | Severe COVID-19† | 1.0 (ref) | 0.97 (0.60 to 1.60) | 0.79 (0.56 to 1.27) | 0.45 (0.18 to 1.07) |
| Female | Severe COVID-19† | 1.0 (ref) | 1.14 (0.64 to 2.09) | 0.57 (0.41 to 0.95) | 0.48 (0.15 to 1.26) |
| Smoking | |||||
| Never smoker | Severe COVID-19† | 1.0 (ref) | 1.25 (0.81 to 1.96) | 0.59 (0.45 to 0.94) | 0.44 (0.23 to 0.99) |
| Ex-smoker | Severe COVID-19† | 1.0 (ref) | 0.67 (0.32 to 1.56) | 0.81 (0.46 to 1.55) | 0.54 (0.14 to 1.45) |
| Current smoker | Severe COVID-19† | 1.0 (ref) | 0.60 (0.17 to 3.85) | 1.19 (0.48 to 2.94) | 0.28 (0.06 to 2.15) |
| Charlson comorbidity index | |||||
| 0 | Severe COVID-19† | 1.0 (ref) | 0.89 (0.51 to 1.63) | 0.52 (0.33 to 0.96) | 0.23 (0.09 to 0.80) |
| 1 | Severe COVID-19† | 1.0 (ref) | 1.00 (0.41 to 2.65) | 0.56 (0.26 to 1.27) | 0.81 (0.31 to 2.41) |
| ≥2 | Severe COVID-19† | 1.0 (ref) | 1.09 (0.63 to 1.95) | 0.81 (0.59 to 1.28) | 0.57 (0.32 to 1.34) |
Numbers in bold indicate significant differences (p<0.05).
Values are adjusted relative risks* (95% CIs; cohort A).
*Regression models were adjusted for age (20–39, 40–59 and ≥60 years); sex; region of residence (Seoul Capital Area, Daegu/Gyeongbuk area, and other area); Charlson comorbidity index (0, 1 and ≥2); history of diabetes mellitus, tuberculosis, stroke and cardiovascular disease; body mass index (continuous; using the restricted cubic spline function); systolic blood pressure (continuous); diastolic blood pressure (continuous); fasting blood glucose (continuous); serum total cholesterol (continuous); glomerular filtration rate (≥90, 60–89 and ≤59 mL/min); household income (low, middle and high); smoking (never, ex and current); alcoholic drinks (<1, 1–2, 3–4 and ≥5 days per week); medication for hypertension, diabetes mellitus and cardiovascular disease.
†Severe COVID-19 consisted of requirement of oxygen therapy, admission to the intensive care unit, invasive ventilation or death.