The incidence of disease flare in women with systemic lupus erythematosus (SLE) increased during pregnancy and within 3 months postpartum, according to the results of a large cohort study published in the Annals of the Rheumatic Diseases.
The investigators estimated the effect of pregnancy on disease flares in women with SLE using data from patients in the Hopkins Lupus Pregnancy Cohort. Women between 14 and 45 years with >1 measurement of disease activity were included in the study. Time-varying exposures were classified as pregnancy; postpartum period; or non-pregnant, non-postpartum periods. Flares were defined as change in Physician Global Assessment (PGA) ≥1 from prior visit and change in Safety of Estrogens in Lupus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) ≥4 from prior visit.
A total of 1349 participants were selected, which included 398 pregnancies in 304 patients. An increased rate of disease flares was reported during pregnancy (hazard ratio [HR], 1.59; 95% CI, 1.27-1.96). Moreover, there was an increase in flares in the initial 3-month postpartum period (HR, 1.48; 95% CI, 1.07-1.95).
When flares were defined by SELENA-SLEDAI, results were comparable with those defined by PGA, with a higher rate of flares reported during pregnancy (HR, 1.57; 95% CI, 1.25-1.92). SELENA-SLEDAI flares occurred most often during the third trimester (54%). Only 15% of all flares during pregnancy and 20% of all flares during non-pregnant, non-postpartum periods achieved scores ≥12.
The researchers found that the rate of flares was modified by the use hydroxychloroquine (HCQ). The HR for flares during pregnancy compared with non-pregnant, non-postpartum periods was estimated at 1.83 (95% CI, 1.34-2.45) in participants not using HCQ vs 1.26 (95% CI, 0.88-1.69) in participants using HCQ. The risk for flare was similarly elevated in non-HCQ users in the 3-month postpartum period, but not in women receiving HCQ following delivery.
The investigators concluded that although the current study supports and extends prior findings regarding an increase in the incidence of flares during pregnancy in women with SLE, continuing HCQ therapy appears to diminish the risk for flares both during and following pregnancy.
Eudy AM, Siega-Riz AM, Engel SM, et al. Effect of pregnancy on disease flares in patients with systemic lupus erythematosus [published online February 20, 2018]. Ann Rheum Dis. doi:10.1136/annrheumdis-2017-212535