Higher postoperative complication rates in patients with systemic lupus erythematosus undergoing surgical and obstetric procedures: a nationwide retrospective matched cohort study.

Population-level evidence on postoperative outcomes in systemic lupus erythematosus (SLE) remains limited. To compare postoperative outcomes between patients with SLE and matched controls and identify factors associated with complications and algorithm-defined disease reactivation. We conducted a nationwide retrospective matched cohort study using DATASUS data. Patients with SLE were matched 1:5 to controls by sex, age group, geographic macro-region, preoperative surgical risk, and surgical category. Postoperative outcomes were assessed over 180 days. Multivariable analyses assessed factors associated with outcomes within the SLE cohort. Sensitivity analyses comprised restriction to elective procedures and exclusion of patients classified with cutaneous lupus. The cohort included 1,708 patients with SLE and 8,540 controls. SLE was associated with increased risks of surgical (RR 2.20, 95% CI 1.91-2.54), clinical (RR 3.30, 95% CI 2.53-4.30), infectious (RR 3.66, 95% CI 2.88-4.64), and other procedure- or care-related complications (RR 11.33, 95% CI 6.19-20.76). Among patients undergoing obstetric procedures, SLE was associated with obstetric complications (RR 1.87, 95% CI 1.37-2.54). Within the SLE cohort, cardiovascular risk was independently associated with higher odds of clinical (adjusted OR 2.75, 95% CI 1.36-5.54) and other procedure- or care-related complications (adjusted OR 5.46, 95% CI 1.84-16.18). Associations between SLE and surgical, clinical, and infectious complications remained significant in both sensitivity analyses. Algorithm-defined SLE reactivation occurred in 3.3%. Patients with SLE had higher risks of several postoperative complications than matched controls. The contributions of disease activity and immunosuppressive treatment warrant further investigation.