Table 2.
Associations of MS disease course and disability with risk of any serious infection, overall and by attained age.
| Overall | Attained age |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| <40 yrs | 40–60 yrs | >60 yrs | |||||||
| Total N | N events | HR (95% CI) | N events | HR (95% CI) | N events | HR (95% CI) | N events | HR (95% CI) | |
| No MS | 86600 | 5576 | REF | 1304 | REF | 2413 | REF | 1859 | REF |
| MS clinical course | |||||||||
| Relapsing-remitting | 5664 | 536 | 1.77 (1.62; 1.93) | 234 | 2.03 (1.76; 2.33) | 238 | 1.67 (1.46; 1.91) | 64 | 1.56 (1.21; 2.00) |
| Progressive | 2996 | 801 | 3.80 (3.52; 4.09) | 64 | 4.68 (3.63; 6.03) | 394 | 4.21 (3.78; 4.69) | 343 | 2.84 (2.53; 3.19) |
| MS EDSS score | |||||||||
| 0.0–5.5 (mild/moderate) | 5677 | 440 | 1.30 (1.18; 1.43) | 136 | 1.24 (1.04; 1.48) | 206 | 1.31 (1.13; 1.51) | 98 | 1.39 (1.14; 1.71) |
| 6.0–9.5 (severe) | 1912 | 449 | 4.26 (3.87; 4.70) | 44 | 5.42 (4.00; 7.34) | 212 | 5.17 (4.48; 5.95) | 193 | 3.42 (2.95; 3.97) |
Hazard ratios comparing rates of serious infections in MS patient groups by disease course and disability with rates in matched individuals from the general population without MS (= reference). All hazard ratios are derived from flexible parametric models and are adjusted for matching factors (age, sex and region of residence) and educational attainment and calendar period of cohort entry.
Abbreviations: MS = multiple sclerosis; EDSS = Expanded Disability Status Scale; HR = hazard ratio; CI = confidence interval; REF = reference category.