Table 1.
Background characteristics of patients and controls.
| MS (n = 510) | Controls (n = 914) | p-value | |
|---|---|---|---|
| Female gender, n (%) | 374 (73.6) | 532 (58.3) | <0.001a |
| Mean age, years (SD) | 50.7 (12.5) | 43.9 (6.9) | <0.001b |
| College/university, 4 years or more, n (%) | 166 (33.3) | 289 (32.5) | 0.27a |
| Ever-smoker, n (%) | 367 (74.9) | 483 (54.5) | <0.001a |
| Relapsing remitting MS, n (%) | 436 (88.8) | – | – |
| Mean age at MS onset, years (SD) | 32.3 (9.2) | – | – |
| Mean disease duration, years (SD) | 18.4 (11.6) | – | – |
| Mean EDSS (SD) | 3.5 (2.3) | – | – |
| Mean MSSS (SD) | 3.9 (2.7) | – | – |
EDSS: Expanded Disability Status Scale; MSSS: Multiple Sclerosis Severity Score; SD: Standard deviation.
a
Pearson’s Chi-square test, bIndependent sample t-test.
Missing values are not included.