PROJECT SUMMARY Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disease that can result in a serious renal manifestation known as lupus nephritis (LN) and eventually, LN-associated end-stage kidney disease (LN-ESKD). The development of LN-ESKD among patients with SLE is of particular concern due to its high risk of premature death and its disproportionate impact on younger patients and patients of minority race and lower socioeconomic status. There are only two treatment options for patients with LN-ESKD, and research suggests that kidney transplantation provides a greater survival benefit compared to long-term dialysis. Despite this, the majority of LN-ESKD patients are initiated on dialysis and it is largely unknown how soon after progression to ESKD that the kidney transplant process is initiated and what socioeconomic and health system barriers may hinder this treatment transition in this population. The kidney transplant process is complex for patients and requires coordinated communication across multiple providers and health systems, including primary care providers, nephrologists, dialysis facilities, and transplant centers. The overarching goal of this research proposal is to characterize early access to kidney transplantation among adult (≥18 years) patients with LN- ESKD in the U.S. by evaluating the impact of socioeconomic and health systems processes on the first step in the kidney transplant process, referral for an evaluation at a transplant center. This research will leverage national surveillance data of ESKD patients from the United States Renal Data System (USRDS) linked with novel patient referral information from the Early Transplant Access Registry that is not collected in national or regional surveillance systems to examine this critical and necessary first step to accessing a transplant. Aim 1 will estimate the timing of 1) kidney transplant referral from ESKD start comparing LN-ESKD patients to patients with ESKD unrelated to LN, using Cox proportional hazards models. Aim 2 will evaluate the association between neighborhood poverty and referral for kidney transplant in patients with LN-ESKD and the potential mediating effect of visiting a kidney specialist prior to ESKD start. Aim 3 will use cross-classified logistic multilevel models to determine the influence of health system factors (including dialysis facility and transplant center characteristics) on referral for kidney transplant in patients with ESKD. The results from this proposed research project will provide insight into the epidemiology of referral for kidney transplant in LN- ESKD patients. Furthermore, it will inform clinical practice among clinicians treating patients with LN-ESKD by emphasizing the importance of timely referral for kidney transplant to reduce patients’ time spent on dialysis and death from other causes while on the waitlist. These results will also inform development of targeted interventions to improve access to a n...