Table 1.
Baseline comparison between DMT-switching and non-switching patients with MS matched by sex, age, and observation period.
| Variables | Total (N = 2722) | Switchers (N = 1361) | Non-switchers (N = 1361) | p |
|---|---|---|---|---|
| Age at MS symptom onset [years], mean (SD)* | 33.4 (10.3) | 33.2 (10.2) | 33.7 (10.4) | 0.233t |
| Disease duration from onset to first DMT [years], mean (SD)* | 2.8 (4.7) | 2.8 (5.0) | 2.8 (4.3) | 0.861t |
| Disease duration from diagnosis to first DMT [years], mean (SD) | 0.95 (1.7) | 0.7 (1.4) | 1.2 (1.9) | <0.001 t |
| Partnership status, N (%)* | 0.113Chi | |||
| Single | 622 (31.4) | 331 (33.1) | 291 (29.7) | |
| Any partnership | 1360 (68.6) | 670 (66.9) | 690 (70.3) | |
| Employment status, N (%)* | 0.639Fi | |||
| In training | 148 (7.5) | 73 (7.4) | 75 (7.7) | |
| Employed – full time | 1048 (53.4) | 522 (52.8) | 526 (54.1) | |
| Employed –part time | 377 (19.2) | 192 (19.4) | 185 (19.0) | |
| Retired – disability | 161 (8.2) | 88 (8.9) | 73 (7.5) | |
| Retired – old age | 38 (1.9) | 15 (1.5) | 23 (2.4) | |
| Other | 189 (9.6) | 98 (9.9) | 91 (9.4) | |
| Educational level, N (%)* | 0.039 Fi | |||
| NSCE | 22 (1.2) | 12 (1.3) | 10 (1.1) | |
| CSE/GCSE | 1093 (57.7) | 568 (59.9) | 525 (55.6) | |
| Advanced technical college entrance qualification | 187 (9.9) | 101 (10.6) | 86 (9.1) | |
| A level | 592 (31.3) | 268 (28.2) | 324 (34.3) | |
| Calendar period of first DMT start, N (%) | 0.011 Chi | |||
| 2014–2017 | 1925 (70.7) | 993 (73.0) | 932 (68.5) | |
| 2018–2021 | 797 (29.3) | 368 (27.0) | 429 (31.5) | |
| First DMT class, N (%) | <0.001 Chi | |||
| Mild-to-moderate efficacy | 2100 (77.1) | 1183 (86.9) | 917 (67.4) | |
| High efficacy | 622 (22.9) | 178 (13.1) | 444 (32.6) | |
| Time on first DMT [years], mean (SD) | 3.0 (2.1) | 1.7 (1.4) | 4.4 (1.7) | <0.001 t |
| EDSS at first DMT start, N (%)* | 0.807Fi | |||
| Mild (0.0–2.5) | 849 (82.1) | 411 (81.7) | 438 (82.5) | |
| Moderate/severe (⩾3.0) | 185 (17.9) | 92 (18.3) | 93 (17.5) | |
| EDSS worsening within 6 months before first DMT cessation/last follow-up, N (%)* | 7 (0.4) | 5 (0.8) | 2 (0.2) | 0.110Chi |
| ARR at first DMT start (95% CI) | 0.23 (0.21–0.25) | 0.26 (0.23–0.29) | 0.20 (0.18–0.23) | 0.005 Kru |
| Relapses within 6 months after first DMT start, N (%) | 211 (7.8) | 147 (10.8) | 64 (4.7) | <0.001 Chi |
| ARR at first DMT cessation/last follow-up (95% CI) | 0.22 (0.19–0.24) | 0.36 (0.32–0.39) | 0.07 (0.06–0.09) | <0.001 Kru |
| MRI results at first DMT start, N (%)* | 0.724Chi | |||
| Stable | 60 (29.9) | 30 (28.3) | 30 (31.6) | |
| Unstable | 141 (70.1) | 76 (71.7) | 65 (68.4) | |
| MRI results within 6 months after first DMT start, N (%)* | 0.990Chi | |||
| Stable | 319 (62.5) | 234 (62.4) | 85 (63.0) | |
| Unstable | 191 (37.5) | 141 (37.6) | 50 (37.0) | |
| MRI results at first DMT cessation/last follow-up, N (%)* | <0.001 Chi | |||
| Stable | 708 (75.9) | 237 (59.0) | 471 (88.7) | |
| Unstable | 225 (24.1) | 165 (41.0) | 60 (11.3) | |
| Matching variables | ||||
| Sex, N (%) | p > 0.999Chi | |||
| Female | 1906 (70.0) | 953 (70.0) | 953 (70.0) | |
| Male | 816 (30.0) | 408 (30.0) | 408 (30.0) | |
| Age at first DMT start [years], mean (SD) | 36.7 (10.6) | 36.2 (10.6) | 36.6 (10.6) | 0.332t |
| Observation period [years], mean (SD) | 4.4 (1.8) | 4.5 (1.8) | 4.4 (1.7) | 0.186t |
*
Denominators may differ due to missing values.
Bold italized indicates statistical significance.
ARR, annualized relapse rate; Chi, chi-square test; CI, confidence interval; CSE/GCSE, certificate of secondary education/ general CSE; DMT, disease-modifying therapy; EDSS, Expanded Disability Status Scale; Fi, Fisher’s exact test; Kru, Kruskal-Wallis test; MRI, magnetic resonance imaging; MS, multiple sclerosis; N, number of patients; NSCE, no school-leaving certificate; SD, standard deviation; t, Student’s t test.