Table 3.
Association of pregnancy and lupus flares defined by SELENA SLEDAIA: the Hopkins Lupus Cohort, 1987–2015 (n=1349).
| Flares | PY | Crude incidence per 100 PY | Crude IRR (95% CI) | Stratified CoxB HR (95% CI) |
|
|---|---|---|---|---|---|
| 12-Month Postpartum Period | |||||
| All patients (n=1349) | |||||
| Not pregnant/postpartum | 2641 | 5583.0 | 47.3 | 1.0 (ref) | 1.0 (ref) |
| Pregnancy | 140 | 220.8 | 63.4 | 1.34 (1.13, 1.59) | 1.57 (1.25, 1.92) |
| 12-months postpartum | 170 | 370.9 | 45.8 | 0.97 (0.83, 1.13) | 1.09 (0.89, 1.32) |
| Patients with ≥1 observed pregnancy in the cohort (n=304) | |||||
| Not pregnant/postpartum | 708 | 1790.4 | 39.5 | 1.0 (ref) | 1.0 (ref) |
| Pregnancy | 140 | 220.8 | 63.4 | 1.60 (1.34, 1.92) | 1.82 (1.34, 2.38) |
| 12-months postpartum | 170 | 370.9 | 45.8 | 1.16 (0.98, 1.37) | 1.32 (1.03, 1.69) |
| 3-Month Postpartum Period | |||||
| All patients (n=1349) | |||||
| Not pregnant/postpartum | 2748 | 5786.3 | 47.5 | 1.0 (ref) | 1.0 (ref) |
| Pregnancy | 140 | 220.8 | 63.4 | 1.34 (1.13, 1.58) | 1.36 (1.06, 1.69) |
| 3-months postpartum | 63 | 95.6 | 65.9 | 1.39 (1.08, 1.78) | 1.37 (0.94, 1.82) |
| Patients with ≥1 observed pregnancy in the cohort (n=304) | |||||
| Not pregnant/postpartum | 815 | 1993.5 | 40.9 | 1.0 (ref) | 1.0 (ref) |
| Pregnancy | 140 | 220.8 | 63.4 | 1.55 (1.30, 1.86) | 1.61 (1.16, 2.16) |
| 3-months postpartum | 63 | 95.6 | 65.9 | 1.61 (1.25, 2.08) | 1.61 (1.02, 2.40) |
A
Flare defined as change in ≥4 from SELENA-SLEDAI score at previous visit
B
Stratified Cox model is a conditional model that does not assume independence of multiple events of flares and allows different baseline hazards based on the number of previous flares a patient experienced
CI: confidence interval; HR: hazard ratio; IRR: incidence rate ratio; PY: person-years; SLE: systemic lupus erythematosus; SLEDAI: SLE Disease Activity Index