Risk factors of significant relapse and appropriate maintenance therapy strategy in SLE-associated immune thrombocytopenia.

Background: Systemic lupus erythematosus-associated immune thrombocytopenia (SLE-ITP) is characterized by relapse. The risk factors of relapse and appropriate maintenance therapy strategy deserve further exploration. Objectives: To determine the risk factors for relapse and appropriate maintenance therapy in significant SLE-ITP patients (a platelet count ⩽30 × 10 Design: Retrospective cohort study using the medical records of 105 patients diagnosed as significant SLE-ITP in Fujian Medical University Union Hospital during December 2012 to March 2021. Patients were followed through a call for observations in January 2022. Methods: Data including demographics, initial clinical feature, induction and maintenance therapy, and outcome at the end of follow-up were analyzed. Risk factors for significant relapse were analyzed using multivariate logistic regression models. The cumulative hazard of significant relapse and the duration of response were estimated, and the differences in outcome between groups were compared using the Cox regression analysis. Results: A total of 65 significant SLE-ITP patients were eligible for the final analysis. Median [interquartile range (IQR)] follow-up duration and median [IQR] duration of response were 62.2 [41.0-79.6] months and 43.4 [20.3-68.7] months, respectively. After the first complete response, 19/65 (29.2%) had a significant relapse. Compared with sustained clinical remission (SCR) + sustained response (SR) group, significant relapse group had a higher proportion of discontinued patients (47.4% Conclusion: Drug withdrawal, especially abrupt withdrawal with insufficient duration of maintenance therapy, is an independent risk factor for significant relapse of SLE-ITP. HCQ combined with GCs is expected to be the first choice of the maintenance therapy for SLE-ITP patients.