Table A1.
Baseline characteristics of unmatched study population by COVID cases versus controls.
| Baseline factor | Category/metric | Cases (n = 2253*) | Controls (n = 6441) | Standardised difference |
|---|---|---|---|---|
| Age | Mean (SD) | 40.26 (11.45) | 43.03 (12.59) | −0.230 |
| Sex | Female | 1576 (70.0) | 4474 (69.5) | 0.011 |
| Male | 677 (30.0) | 1967 (30.5) | ||
| Disease duration (years) | Mean (SD) | 9.45 (8.14) | 11.34 (8.99) | −0.221 |
| Baseline EDSS | Median (IQR) | 1.5 (1, 3) | 2 (1, 4) | −0.130 |
| MS course | CIS | 254 (11.3) | 301 (4.7) | −0.257 |
| PP | 85 (3.8) | 292 (4.5) | ||
| PR | 24 (1.1) | 70 (1.1) | ||
| RR | 1757 (78.0) | 5109 (79.3) | ||
| SP | 133 (5.9) | 530 (8.2) | ||
| Not reported | 0 (0.0) | 139 (2.2) | ||
| Relapses 1-year pre-baseline | Mean (SD) | 0.06 (0.29) | 0.21 (0.50) | −0.353 |
| Relapses 2-year pre-baseline | Mean (SD) | 0.10 (0.42) | 0.39 (0.72) | −0.496 |
| DMT class | High efficacy | 1125 (49.9) | 2403 (37.3) | −0.331 |
| Low-moderate efficacy | 771 (34.2) | 2182 (33.9) | ||
| No baseline DMT | 357 (15.9) | 1856 (28.8) | ||
| Country | Argentina | 20 (0.9) | 158 (2.5) | −0.257 |
| Australia | 265 (11.8) | 984 (15.3) | ||
| Belgium | 52 (2.3) | 364 (5.7) | ||
| Brazil | 21 (0.9) | 65 (1.0) | ||
| Spain | 231 (10.3) | 865 (13.4) | ||
| Croatia | 214 (9.5) | 24 (0.4) | ||
| Italy | 296 (13.1) | 392 (6.1) | ||
| Kuwait | 149 (6.6) | 821 (12.8) | ||
| Mexico | 3 (0.1) | 8 (0.1) | ||
| Romania | 3 (0.1) | 2 (0.0) | ||
| Saudi Arabia | 9 (0.4) | 66 (1.0) | ||
| Turkey | 990 (43.9) | 2692 (41.8) |
Values are expressed as n (%), median (IQR) or mean (SD). Standardised difference is the difference in means or proportions divided by the standard error. An imbalance was defined as an ASD > 0.10, indicated in bold.
*
239 of the original 2492 cases were excluded for not having a baseline EDSS
ASD, absolute standardised difference; CIS, clinically isolated syndrome; DMT, disease-modifying therapy; EDSS, Expanded Disability Status Scale; MS, multiple sclerosis; PP, primary progressive; PR, progressive relapsing; RR, relapsing remitting; SP, secondary progressive; SD, standard deviation.