Incidence rate ratio for ischaemic cerebrovascular disorder in SLE 1998–2016
| Age at event | All ages | Age <40 years | Ages 40–59 years | Age ≥60 years | ||||
| SLE | Non-SLE | SLE | Non-SLE | SLE | Non-SLE | SLE | Non-SLE | |
| Both sexes | ||||||||
| n (mean prevalence) | 115 | 196 259 | 18 | 77 294 | 40 | 65 211 | 57 | 53 754 |
| Events | 16 | 8457 | 0 | 169 | 4 | 910 | 12 | 7424 |
| Incidence ratio/1000 patient-years | 4.5 | 2.2 | – | – | 5.3 | 0.71 | 11.0 | 7.3 |
| Crude IRR | 2.1 | – | 7.5 | 1.5 | ||||
| CI (99/99.9%) P value | 1.5 to 2.8 <0.001 | 4.5 to 12.7 <0.001 | 1.1 to 2.1 <0.01 | |||||
| Females | ||||||||
| n | 101 | 99 425 | 15 | 37 806 | 36 | 32 535 | 50 | 29 084 |
| Events | 14 | 4115 | 0 | 56 | 4 | 313 | 10 | 3746 |
| IR/1000 patient-years | 7.3 | 2.2 | – | – | 5.8 | 0.5 | 10.5 | 6.8 |
| Crude IRR | 3.3 | – | 11.6 | 1.5 | ||||
| CI (95/99.9%) P value | 2.4 to 4.6 <0.001 | 2.0 to 6.1 <0.001 | 1.1 to 2.0 <0.05 | |||||
| Males | ||||||||
| n | 14 | 96 834 | 3 | 39 488 | 4 | 32 676 | 7 | 24 670 |
| Events | 2 | 4342 | 0 | 67 | 0 | 597 | 2 | 3778 |
| IR/1000 patient-years | 7.5 | 2.4 | – | – | – | – | 15.0 | 7.8 |
| Crude IRR | 3.1 | 1.9 | ||||||
| CI (95%) P value | 1.8 to 5.2 <0.05 | 0.9 to 4.0 n.s. | ||||||
IR, incidence rate; IRR, incidence rate ratio; n.s., not significant.