Table 1.
Comparison of baseline characteristics between cases and controls.
| Variables * | Age < 65 (n = 316) | Age ≥ 65 (n = 316) | p-Value |
|---|---|---|---|
| Background data | |||
| Age, years (mean ± SD) | 58.0 ± 11.8 | 71.4 ± 9.2 | <0.001 |
| BMI, kg/m2 (mean ± SD) | 24.4 ± 4.1 | 24.8 ± 4.0 | 0.214 |
| Gender (men) | 172 (54.4%) | 172 (54.4%) | 1 |
| Area of residence (urban) | 187 (59.2%) | 169 (53.5%) | 0.148 |
| Smoking | 114 (36.1%) | 95 (30.1%) | 0.108 |
| Chronic alcohol use | 24 (7.6%) | 29 (9.2%) | 0.473 |
| Complete COVID-19 Vaccination | 7 (2.2%) | 13 (4.1%) | 0.172 |
| Hepatitis B vaccine | 11 (3.5%) | 6 (1.9%) | 0.218 |
| Comorbidities | |||
| Malignancy | 18 (5.7%) | 25 (7.9%) | 0.268 |
| Chronic lung disease | 28 (8.9%) | 39 (12.3%) | 0.155 |
| Cardiovascular disease | 107 (33.9%) | 132 (41.8%) | 0.040 |
| Cerebrovascular disease | 24 (7.6%) | 49 (15.5%) | 0.001 |
| Diabetes mellitus | 41 (13.0%) | 48 (15.2%) | 0.423 |
| Autoimmune disease | 13 (4.1%) | 15 (4.7%) | 0.699 |
| Chronic kidney disease | 16 (5.1%) | 21 (6.6%) | 0.396 |
| Digestive and liver disease ** | 23 (7.3%) | 30 (9.5%) | 0.315 |
| CCI score (≥2) | 76 (24.1%) | 107 (33.9%) | 0.006 |
| Oxygen supplementation | <0.001 | ||
| No supplementation | 35 (11.1%) | 12 (3.8%) | |
| Non-invasive ventilation | 241 (76.3%) | 248 (78.5%) | |
| Invasive ventilation | 40 (12.7%) | 56 (17.7%) | |
| COVID-19 severity | 0.016 | ||
| Mild | 106 (33.5%) | 82 (25.9%) | |
| Moderate | 121 (38.3%) | 113 (35.8%) | |
| Severe | 89 (28.2%) | 121 (38.3%) | |
| Disease outcomes | |||
| Days of hospitalization (mean ± SD) | 11 ± 6.6 | 19 ± 8.3 | <0.001 |
| ICU admission | 40 (12.7%) | 72 (22.8%) | <0.001 |
| In-hospital mortality | 28 (8.9%) | 54 (17.1%) | 0.002 |
* Data reported as n (%) and calculated using Chi-square test and Fisher’s exact unless specified differently; ** Liver disease including fatty liver disease, hepatitis B and C infection, drug-induced liver disease; BMI—body mass index; ICU—intensive care unit; CCI—Charlson Comorbidity Index.