Number of events, time at risk, crude incidence rates and fully adjusted HRs for VTE in Swedish patients with RA by b/tsDMARD cohort between 2010 and 2021. Stratified by sex, age, line of therapy, history of VTE, RA serostatus, any VTE risk factor and RA disease activity.
| Stratification | Obs, N | Events, N | PYs at risk | IR/1000 PYs (95% CI) | HR (95% CI) | ||||
| TNFi | Rituximab | IL6i | Abatacept | JAKi | |||||
| Overall | 32 737 | 559 | 91 824 | 6.09 (5.60 to 6.61) | 1 (ref) | 0.94 (0.74 to 1.20) | 1.25 (0.94 to 1.67) | 0.89 (0.66 to 1.21) | 1.73 (1.24 to 2.42) |
| Sex | |||||||||
| Male | 7 407 | 177 | 22 010 | 8.04 (6.94 to 9.32) | 1 (ref) | 1.09 (0.70 to 1.71) | 2.30 (1.43 to 3.70) | 0.92 (0.49 to 1.70) | 2.66 (1.44 to 4.92) |
| Female | 25 330 | 382 | 69 815 | 5.47 (4.95 to 6.05) | 1 (ref) | 0.90 (0.70 to 1.20) | 0.91 (0.63 to 1.32) | 0.89 (0.62 to 1.26) | 1.53 (1.02 to 2.30) |
| Age | |||||||||
| <60 | 16 820 | 140 | 47 196 | 2.97 (2.51 to 3.50) | 1 (ref) | 1.43 (0.87 to 2.35) | 1.27 (0.69 to 2.34) | 0.69 (0.32 to 1.48) | 2.11 (1.09 to 4.07) |
| 60 or above | 15 917 | 419 | 44 628 | 9.39 (8.53 to 10.33) | 1 (ref) | 0.85 (0.65 to 1.13) | 1.27 (0.92 to 1.77) | 0.97 (0.70 to 1.36) | 1.64 (1.11 to 2.44) |
| No of previous b/tsDMARDs (ever) | |||||||||
| 0 | 15 068 | 259 | 46 795 | 5.53 (4.90 to 6.25) | 1 (ref) | 0.82 (0.56 to 1.19) | 1.36 (0.77 to 2.39) | 0.60 (0.30 to 1.19) | 1.67 (0.81 to 3.44) |
| 1 | 7 981 | 148 | 22 205 | 6.67 (5.67 to 7.83) | 1 (ref) | 1.61 (1.06 to 2.46) | 1.18 (0.69 to 2.02) | 1.25 (0.74 to 2.12) | 1.74 (0.82 to 3.70) |
| two or more | 9 688 | 152 | 22 824 | 6.66 (5.68 to 7.81) | 1 (ref) | 0.65 (0.38 to 1.10) | 1.24 (0.76 to 2.02) | 0.81 (0.49 to 1.36) | 1.60 (0.97 to 2.65) |
| History of VTE | |||||||||
| Yes | 1 249 | 125 | 3 066 | 40.77 (34.22 to 48.59) | 1 (ref) | 0.58 (0.33 to 1.01) | 0.79 (0.42 to 1.49) | 0.78 (0.42 to 1.44) | 1.07 (0.53 to 2.14) |
| No | 31 488 | 434 | 88 759 | 4.89 (4.45 to 5.37) | 1 (ref) | 1.06 (0.81 to 1.39) | 1.42 (1.03 to 1.96) | 0.94 (0.65 to 1.33) | 1.95 (1.33 to 2.87) |
| RA serostatus | |||||||||
| Seropositive | 26 012 | 460 | 74 186 | 6.20 (5.66 to 6.79) | 1 (ref) | 0.91 (0.71 to 1.18) | 1.31 (0.96 to 1.80) | 0.81 (0.57 to 1.16) | 1.71 (1.17 to 2.49) |
| Seronegative | 6 725 | 99 | 17 639 | 5.61 (4.61 to 6.83) | 1 (ref) | 1.20 (0.56 to 2.57) | 1.06 (0.52 to 2.17) | 1.09 (0.57 to 2.08) | 1.76 (0.84 to 3.71) |
| ≥1 VTE risk factor* | |||||||||
| Yes | 18 814 | 401 | 51 553 | 7.78 (7.05 to 8.58) | 1 (ref) | 0.83 (0.63 to 1.11) | 1.16 (0.83 to 1.63) | 0.89 (0.63 to 1.27) | 1.66 (1.13 to 2.43) |
| No | 13 923 | 158 | 40 271 | 3.92 (3.36 to 4.59) | 1 (ref) | 1.36 (0.88 to 2.12) | 1.91 (1.09 to 3.34) | 1.12 (0.50 to 2.11) | 1.72 (0.85 to 3.48) |
| RA disease activity | |||||||||
| DAS28 ≥5.1 (high) | 7 853 | 161 | 22 126 | 7.27 (6.24 to 8.49) | 1 (ref) | 0.52 (0.31 to 0.87) | 1.40 (0.89 to 2.22) | 0.86 (0.50 to 1.50) | 1.33 (0.67 to 2.65) |
| DAS28 <5.1 | 12 232 | 210 | 35 760 | 5.87 (5.13 to 6.72) | 1 (ref) | 0.96 (0.64 to 1.45) | 1.19 (0.71 to 1.99) | 0.75 (0.44 to 1.29) | 1.71 (0.96 to 3.03) |
*Defined as any of age >60 years, cancer, previous VTE, major surgery within 90 days, coagulation disorder, varicose veins, hormone replacement therapy, high DAS28, HAQ score >1 or ever smoker.
b/tsDMARD, biologic/targeted synthetic disease-modifying antirheumatic drug; DAS28, Disease Activity Score 28; HAQ, Health Assessment Questionnaire; IL6i, interleukin 6 inhibitor; IR, incidence rate; JAKi, Janus kinase inhibitor; PY, person years; RA, rheumatoid arthritis; TNFi, Tumour necrosis factor inhibitor; VTE, venous thromboembolism.