Table 3

Association of pregnancy and lupus flares defined by SELENA-SLEDAI*: the Hopkins Lupus Cohort, 1987–2015 (n=1349)

FlaresPYCrude incidence per 100 PYCrude IRR (95% CI)Stratified Cox†
HR (95% CI)
12-month postpartum period
 All patients (n=1349)
  Not pregnant/postpartum26415583.047.31.0 (ref)1.0 (ref)
  Pregnancy140220.863.41.34 (1.13 to 1.59)1.57 (1.25 to 1.92)
  12 months postpartum170370.945.80.97 (0.83 to 1.13)1.09 (0.89 to 1.32)
 Patients with ≥1 observed pregnancy in the cohort (n=304)
  Not pregnant/postpartum7081790.439.51.0 (ref)1.0 (ref)
  Pregnancy140220.863.41.60 (1.34 to 1.92)1.82 (1.34 to 2.38)
  12 months postpartum170370.945.81.16 (0.98 to 1.37)1.32 (1.03 to 1.69)
3-month postpartum period
 All patients (n=1349)
  Not pregnant/postpartum27485786.347.51.0 (ref)1.0 (ref)
  Pregnancy140220.863.41.34 (1.13 to 1.58)1.36 (1.06 to 1.69)
  3 months postpartum6395.665.91.39 (1.08 to 1.78)1.37 (0.94 to 1.82)
 Patients with ≥1 observed pregnancy in the cohort (n=304)
  Not pregnant/postpartum8151993.540.91.0 (ref)1.0 (ref)
  Pregnancy140220.863.41.55 (1.30 to 1.86)1.61 (1.16 to 2.16)
  3 months postpartum6395.665.91.61 (1.25 to 2.08)1.61 (1.02 to 2.40)
  • *Flare defined as change in ≥4 from SELENA-SLEDAI score at previous visit.

  • †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.

  • IRR, incidence rate ratio; PY, person-years; SLE, systemic lupus erythematosus; SLEDAI, SLE Disease Activity Index.