Long-Term Outcomes of Systemic Lupus Erythematous Patients after Pregnancy: A Nationwide Population-Based Cohort Study

BACKGROUND Data on long-term maternal outcomes in patients with systemic lupus erythematosus (SLE) are lacking. The study aimed to explore the relationships among SLE, pregnancy, outcomes of end-stage renal disease (ESRD), and overall mortality. METHODS We established a retrospective cohort study consisting of four cohorts: pregnant (case cohort) and nonpregnant SLE patients, as well as pregnant and nonpregnant non-SLE patients. One case cohort and three comparison cohorts were matched by age at first pregnancy and index date of pregnancy by using the Taiwan National Health Insurance Research Dataset. All study subjects were selected based on the index date to the occurrence of ESRD or overall death. Cox proportional hazard regression models and Kaplan-Meier curves were used in the analysis. RESULTS SLE pregnant patients exhibited significantly increased risk of ESRD after adjusting for other important confounders, including immunosuppressant and parity (HR = 3.19, 95% CI: 1.35-7.52 for pregnant non-SLE; and HR = 2.77, 95% CI: 1.24-6.15 for nonpregnant non-SLE patients). No significant differences in ESRD incidence were observed in pregnant and nonpregnant SLE patients. Pregnant SLE patients exhibited better clinical condition at the baseline and a significantly lower risk of overall mortality than nonpregnant SLE patients. CONCLUSIONS Our data support current recommendations for SLE patients to avoid pregnancy until disease activity is quiescent. Multicenter recruitment and clinical information can be used to further examine the association of SLE and ESRD (or mortality) after pregnancy.