Table 2. Events, Crude Incidence Rates, and Cox Proportional Hazard Models Comparing Cohorts for Each Outcome.
| Factor | No. of Events | Incidence Rate per 1000 Person-Years (95% CI) | Hazard Ratio (95% CI)a | Hazard Ratio (95% CI)b,c | Hazard Ratio (95% CI)b,d |
|---|---|---|---|---|---|
| Serious infections | |||||
| Interferon beta and GA | 41 | 8.9 (6.4-12.1) | 1 [Reference] | 1 [Reference] | 0.59 (0.38-0.90) |
| Fingolimod | 57 | 14.3 (10.8-18.5) | 1.81 (1.21-2.71) | 1.30 (0.84-2.03) | 0.77 (0.54-1.09) |
| Natalizumab | 44 | 11.4 (8.3-15.3) | 1.53 (0.99-2.35) | 1.12 (0.71-1.77) | 0.66 (0.45-0.97) |
| Rituximab | 124 | 19.7 (16.4-23.5) | 2.34 (1.65-3.33) | 1.70 (1.11-2.61) | 1 [Reference] |
| General population | 734 | 5.2 (4.8-5.5) | 0.65 (0.47-0.89) | NA | NA |
| Any antibiotic use | |||||
| Interferon beta and GA | 604 | 207.3 (191.1-224.5) | 1 [Reference] | 1 [Reference] | 0.81 (0.71-0.92) |
| Fingolimod | 506 | 215.6 (197.2-235.2) | 1.11 (0.99-1.25) | 1.06 (0.93-1.20) | 0.86 (0.76-0.97) |
| Natalizumab | 554 | 247.1 (227.0-268.6) | 1.21 (1.08-1.36) | 1.15 (1.01-1.31) | 0.94 (0.83-1.06) |
| Rituximab | 968 | 252.4 (236.7-268.8) | 1.21 (1.10-1.34) | 1.23 (1.08-1.40) | 1 [Reference] |
| General population | 13 596 | 149.0 (146.5-151.6) | 0.77 (0.71-0.84) | NA | NA |
| Herpes antiviral use | |||||
| Interferon beta and GA | 75 | 16.6 (13.1-20.9) | 1 [Reference] | 1 [Reference] | 0.94 (0.67-1.31) |
| Fingolimod | 125 | 32.5 (27.0-38.7) | 2.09 (1.57-2.77) | 1.82 (1.34-2.46) | 1.70 (1.30-2.24) |
| Natalizumab | 134 | 35.6 (29.8-42.1) | 2.14 (1.62-2.84) | 1.71 (1.27-2.32) | 1.61 (1.21-2.13) |
| Rituximab | 145 | 23.5 (19.9-27.7) | 1.40 (1.06-1.85) | 1.07 (0.76-1.49) | 1 [Reference] |
| General population | 1300 | 9.3 (8.8-9.8) | 0.60 (0.47-0.76) | NA | NA |
Abbreviations: GA, glatiramer acetate; NA, not applicable.
a
Hazard ratios adjusted for age and sex.
b
Hazard ratios adjusted for age, sex, educational level, country of birth, sick leave, disability pension, hospitalizations in the previous 5 years, history of infections, cancer, antidepressant use, antipsychotic use, major adverse cardiovascular events, arrhythmia, year of treatment start, region of treating clinic, relapses last year, multiple sclerosis duration, Expanded Disability Status Scale, Multiple Sclerosis Impact Scale–29, EuroQol 5-Dimension scale, and Symbol Digit Modalities Test.
c
This comparison is defined by the reference group interferon beta and GA.
d
This comparison is defined by the reference group rituximab.