Adjusted relative risk (95% CIs) of SARS-CoV-2 infection, severe COVID-19 outcomes and COVID-19 related deaths associated with study patients who engaged in physical activities according to exercise guideline (cohort A)
| Event | Types of physical activity | |||
| Insufficient aerobic and muscle strengthening | Muscle strengthening only | Aerobic only | Aerobic and muscle strengthening | |
| COVID-19, n (%) | 1293/41 293 (3.1) | 150/5036 (3.0) | 561/18 994 (3.0) | 291/11 072 (2.6) |
| Adjusted RR (95% CI) | ||||
| Model 1* (age and sex adjusted) | 1.0 (ref) | 1.08 (0.91 to 1.29) | 0.98 (0.88 to 1.09) | 0.87 (0.75 to 0.98) |
| Model 2† (fully adjusted) | 1.0 (ref) | 1.01 (0.73 to 1.42) | 0.92 (0.77 to 1.12) | 0.84 (0.73 to 0.96) |
| Model 3‡ (selected confounders by DAGs) | 1.0 (ref) | 1.03 (0.86 to 1.22) | 0.97 (0.88 to 1.07) | 0.85 (0.72 to 0.98) |
| Severe COVID-19§, n (%) | 273/41 293 (0.66) | 25/5036 (0.50) | 109/18 994 (0.57) | 39/11 072 (0.35) |
| Adjusted RR (95% CI) | ||||
| Model 1* (age and sex adjusted) | 1.0 (ref) | 0.85 (0.56 to 1.29) | 0.87 (0.70 to 1.09) | 0.59 (0.39 to 0.87) |
| Model 2† (fully adjusted) | 1.0 (ref) | 0.93 (0.61 to 1.42) | 0.86 (0.69 to 1.08) | 0.42 (0.19 to 0.91) |
| Model 3‡ (selected confounders by DAGs) | 1.0 (ref) | 0.88 (0.58 to 1.33) | 0.86 (0.69 to 1.08) | 0.56 (0.34 to 0.88) |
| COVID-19 related death, n (%) | 32/41 293 (0.08) | 0/5036 (0.00) | 11/18 994 (0.06) | 2/11 072 (0.02) |
| Adjusted RR (95% CI) | ||||
| Model 1* (age and sex adjusted) | 1.0 (ref) | NA | 0.70 (0.35 to 1.41) | 0.23 (0.06 to 0.98) |
| Model 2† (fully adjusted) | 1.0 (ref) | NA | 0.71 (0.34 to 1.41) | 0.26 (0.07 to 0.99) |
| Model 3‡ (selected confounders by DAGs) | 1.0 (ref) | NA | 0.71 (0.34 to 1.40) | A0.24 (0.06 to 0.99) |
Numbers in bold indicate significant differences (p<0.05).
*Model 1: adjusted for age (20–39, 40–59 and ≥60 years) and sex.
†Model 2: adjusted for the age; sex; region of residence (Seoul Capital Area, Daegu/Gyeongbuk area and other areas); Charlson comorbidity index (0, 1 and ≥2); history of diabetes mellitus, tuberculosis, stroke and cardiovascular disease; body mass index (continuous; using the cubic spline function); systolic blood pressure (continuous; using the restricted cubic spline function); 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); and medication for hypertension, diabetes mellitus and cardiovascular disease.
‡Model 3: adjusted for potential confounders selected by DAGs (age; sex; region of residence; household income; smoking; and alcoholic drinks).
§Severe COVID-19 consisted of requirement of oxygen therapy, admission to the intensive care unit, invasive ventilation or death.
DAGs, directed acyclic graphs; RR, relative risk.