Abstract Background/Aims Systemic Lupus Erythematosus (SLE) is a multisystem autoimmune disease with variable presentation and clinical manifestations. Previous research has established the higher risk of incident cardiovascular disease and stroke in SLE patients. However, the evidence on how stroke outcomes differ between SLE and non-SLE patient groups in contemporary practice is limited. Furthermore, given that SLE tends to affect predominantly females, with a female-to-male ratio of 9:1, the question remains if and to what extent stroke outcomes might differ between males and females with SLE. Thus, we aimed to explore sex-specific acute stroke outcomes amongst patients with comorbid SLE. Methods A total of 316,531 records representing 1,581,430 acute stroke hospitalisations between 2015 and 2018 from the United States National Inpatient Sample (NIS) were analysed. The primary exposure of interest was comorbid SLE. Patients were grouped according to SLE status and sex (no SLE-reference, male with SLE, female with SLE). Outcome measures of interest (in-patient mortality, length-of-stay in hospital [LoS] and routine home discharge) were examined utilising multivariable logistic regressions, adjusting for age, ethnicity, stroke type, receipt of revascularisation therapies, region, hospital status and 49 comorbidities including major cardiovascular disease. Results The median (interquartile range) age was 71 (60-82) years. There were 940 (0.06%) males and 6110 (0.39%) females with SLE. After adjustments, female patients with SLE had 21% increased odds of dying in hospital, adjusted odds ratios (aOR) = 1.21, 95% CI (0.92 - 1.61), whereas the risk of in-patient mortality for male patients with SLE was 24% lower compared to the reference group, aOR = 0.76 (0.32 - 1.81). However, none of the differences in the in-patient mortality were of statistical significance. Secondly, compared to patients without SLE, females with SLE had significantly longer hospitalisation, aOR=1.20 (1.06 - 1.36), while there was no significant difference for males with SLE, aOR=1.06 (0.75 - 1.49). The odds of being routinely discharged were 28% lower for females with SLE, aOR=0.72, (0.63 - 0.82), in comparison to a non-significant increase in the odds of 18% for males with SLE, aOR=1.18, (0.84 - 1.65). Conclusion Our results highlight the sex differences in acute stroke outcomes in patients with SLE. Due to a small sample size of males with SLE, our findings need to be cautiously interpreted. Further understanding of the influence of SLE amongst male patients with acute stroke is needed. Disclosure S. Jesenakova: None. T.A. Pana: None. B. Carter: None. M.O. Mohamed: None. M.A. Mamas: None. P.K. Myint: None.