Multivariable ordinal logistic regression analysis of factors associated with the 3-point ordinal COVID-19 severity outcome scale (no hospitalisation, hospitalisation, death), with comorbidity count instead of comorbidities listed individually (N=348, primary analysis)
| OR (95% CI) | P value | |
| Age (per decade) | 1.59 (1.31 to 1.91) | <0.001 |
| Male sex | 1.57 (0.95 to 2.59) | 0.076 |
| Region | ||
| Europe | REF | n/a |
| North America | 0.87 (0.48 to 1.58) | 0.648 |
| Other | 4.55 (2.37 to 8.76) | <0.001 |
| Pandemic calendar period | ||
| On/before 15 June 2020 | REF | n/a |
| 16 June to 30 September 2020 | 0.55 (0.26 to 1.20) | 0.132 |
| On/after 1 October 2020 | 0.61 (0.37 to 1.00) | 0.051 |
| Comorbidities | ||
| None | REF | n/a |
| One | 1.41 (0.73 to 2.74) | 0.305 |
| Two or more | 2.63 (1.39 to 4.98) | 0.003 |
| Disease activity | ||
| Remission | REF | n/a |
| Low/moderate disease activity | 1.19 (0.63 to 2.25) | 0.594 |
| High disease activity | 3.50 (1.25 to 9.83) | 0.018 |
| Glucocorticoid (prednisolone-equivalent dose) | ||
| No glucocorticoids | REF | n/a |
| >0 to 7.5 mg/day | 1.08 (0.57 to 2.05) | 0.820 |
| >7.5 mg/day | 2.40 (1.09 to 5.28) | 0.031 |
| IVIg | 0.42 (0.15 to 1.18) | 0.101 |
| DMARD/immunosuppressant medication category | ||
| csDMARD only (HCQ/MTX/SSZ/LEF monotherapy or combination therapy) | REF | n/a |
| No DMARD/immunosuppressant | 1.85 (0.90 to 3.78) | 0.094 |
| AZA monotherapy | 1.78 (0.71 to 4.43) | 0.216 |
| MMF monotherapy | 1.25 (0.54 to 2.89) | 0.601 |
| AZA/MMF combination therapy (except combination with RTX or b/tsDMARDs) | 0.77 (0.27 to 2.15) | 0.615 |
| CSA/CYC/TAC monotherapy or combination therapy (except RTX/b/tsDMARDs) | 1.61 (0.54 to 4.79) | 0.386 |
| b/tsDMARD monotherapy or combination therapy (except RTX) | 1.65 (0.50 to 5.43) | 0.411 |
| RTX (monotherapy or combination therapy with any other drug) | 2.71 (1.28 to 5.72) | 0.009 |
Statistically significant OR are highlighted in bold.
AZA, azathioprine; bDMARD, biologic DMARD; CSA, ciclosporin; csDMARD, conventional synthetic DMARD; CYC, cyclophosphamide; DMARD, disease-modifying antirheumatic drug; HCQ, hydroxychloroquine; IL, interleukin; IVIg, intravenous immunoglobulin; IVIg, intravenous immunoglobulin; JAKi, Janus kinase inhibitors; LEF, leflunomide; MMF, mycophenolate mofetil; MTX, methotrexate; RTX, rituximab; SSZ, sulfasalazine; TAC, tacrolimus; TNF, tumour necrosis factor; tsDMARD, targeted synthetic DMARD.