Table 3 Incidence rates and incidence rate ratios of surgery for systemic lupus erythematosus cohort and comparison cohort, with stratification by age group (N = 3462)
Type of surgery (ICD-9-CM) | Age group (years) | systemic lupus erythematosus cohort | comparison cohort | IRR (95% CI) | aIRR (95% CI) | ||||
|---|---|---|---|---|---|---|---|---|---|
P value | P value | ||||||||
No. of patients | Person-years | IR | No. of patients | Person-years | IR | ||||
THR (81.51) | 20–44 | 8 | 2391.0 | 334.6 | 4 | 12,548.0 | 31.9 | 10.53 (3.17–34.96) < 0.001 | 7.70 (2.19–27.12) 0.001 |
45–64 | 3 | 1087.8 | 275.8 | 2 | 5563.3 | 35.9 | 7.67 (1.28–45.90) 0.026 | 4.69 (0.64–34.07) 0.127 | |
65–80 | 1 | 164.6 | 607.5 | 1 | 933.6 | 107.1 | 5.67 (0.36–90.66) 0.220 | 1.98 (0.10–40.49) 0.657 | |
TKR (81.54) | 20–44 | 1 | 2417.4 | 41.4 | 0 | 12,604.5 | 0.0 | NC | NC |
45–64 | 5 | 1071.4 | 466.7 | 10 | 5532.2 | 180.8 | 2.58 (0.88–7.55) 0.083 | 2.66 (0.90–7.90) 0.078 | |
65–80 | 0 | 171.1 | 0.0 | 5 | 905.3 | 552.3 | NC | NC | |