Table 1.
Baseline Characteristics of Systemic Autoimmune Rheumatic Disease (SARD) Patients and Non-SARD Comparators with COVID-19
| Unmatched Cohorts | Exposure Score-Matched Cohorts† | Extended Exposure Score-Matched Cohorts‡ | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Characteristics* | SARD Patients | Non-SARD Comparators | Std. Diff. | SARD Patients | Non-SARD Comparators | Std. Diff. | SARD Patients | Non-SARD Comparators | Std. Diff. |
| N | 2,379 | 142,750 | 2,379 | 2,379 | 2,374 | 2,374 | |||
| Age, years, mean (SD) | 58 (16) | 47 (19) | 0.61 | 58 (16) | 57 (16) | 0.01 | 58 (16) | 58 (16) | 0.02 |
| Female, n (%) | 1,873 (79) | 77,438 (54) | 0.54 | 1,873 (79) | 1,873 (79) | <0.01 | 1,868 (79) | 1,866 (79) | <0.01 |
| Race/Ethnicity, n (%) | |||||||||
| White | 1,295 (54) | 72,946 (51) | 0.07 | 1,295 (54) | 1,295 (54) | <0.01 | 1,293 (54) | 1,297 (55) | <0.01 |
| Black | 649 (27) | 32,347 (23) | 0.11 | 649 (27) | 649 (27) | <0.01 | 648 (27) | 662 (28) | 0.01 |
| Hispanic | 312 (13) | 26,388 (18) | 0.15 | 312 (13) | 312 (13) | <0.01 | 312 (13) | 304 (13) | 0.01 |
| Comorbidities, n (%) | |||||||||
| Hypertension | 1,206 (51) | 24,171 (17) | 0.76 | 1,206 (51) | 758 (32) | 0.39 | 1,201 (51) | 1,209 (51) | 0.01 |
| Ischemic Heart Disease | 360 (15) | 5,378 (4) | 0.40 | 360 (15) | 165 (7) | 0.26 | 355 (15) | 348 (15) | 0.01 |
| Chronic Kidney Disease | 376 (16) | 5,549 (4) | 0.41 | 376 (16) | 183 (8) | 0.25 | 372 (16) | 361 (15) | 0.01 |
| Diabetes Mellitus | 599 (25) | 13,026 (9) | 0.44 | 599 (25) | 384 (16) | 0.22 | 595 (25) | 588 (25) | 0.01 |
| Asthma | 372 (16) | 5,800 (4) | 0.40 | 372 (16) | 200 (8) | 0.22 | 367 (15) | 360 (15) | 0.01 |
| COPD | 87 (4) | 969 (1) | 0.21 | 87 (4) | 34 (1) | 0.14 | 85 (4) | 74 (3) | 0.03 |
| BMI, kg/m2, mean (SD) | 30.7 (8.2) | 30.5 (7.9) | 0.02 | 30.7 (8.2) | 30.6 (7.8) | <0.01 | 30.7 (8.2) | 31.0 (8.2) | 0.03 |
| Creatinine, mg/dL, mean (SD) | 1.1 (1.3) | 1.2 (2.6) | 0.01 | 1.1 (1.3) | 1.1 (1.2) | 0.03 | 1.1 (1.3) | 1.3 (1.7) | 0.10 |
| Prior Hospitalization, n (%) | 360 (15) | 5,761 (4) | 0.38 | 360 (15) | 187 (8) | 0.23 | 355 (15) | 335 (14) | 0.02 |
*
Assessed in year prior to index date. SARD, systemic autoimmune rheumatic disease; COPD, chronic obstructive pulmonary disease; BMI, body mass index; Std. Diff., standardized difference.
†
One-to-one exposure score-matching was performed using a method analogous to propensity score-matching. The exposure score included age, sex, race/ethnicity, and BMI.
‡
Extended exposure score included age, sex, race/ethnicity, BMI, comorbidities, and prior hospitalization.