Background/Purpose:

Lupus nephritis is a major complication of systemic lupus erythematosus (SLE), occurring in up to half all SLE patients and progressing to end-stage renal disease (ESRD) in 20% of those affected. Renal transplantation is a preferred treatment, but this is a limited resource, and the survival benefit of transplantation has not been well-characterized in this population. We assessed survival impact following waitlisting for a renal transplant in patients with SLE in the US.

Methods:

We identified all incident cases of ESRD due to SLE (ICD9=710.0) in the United States Renal Data System (USRDS) between 1995 and 2014. The USRDS captures nearly all patients with ESRD in the US and includes the cause of ESRD by ICD9 code as well as demographics, comorbidities, and dates of waitlist entry, transplantation and death including its causes. We included all patients with ESRD due to SLE who were waitlisted for a renal transplant during the study period and followed patients until death or January 1, 2016. We restricted our analysis to patients waitlisted for transplant to limit the potential bias of confounding by indication. We used a time-varying Cox regression analysis to estimate the hazard ratio (HR) for death following renal transplantation compared to those who remained on the waitlist, while adjusting for age, sex, body mass index, tobacco use, comorbidities, and first ESRD treatment modality at baseline. We also assessed differences in cause of death using cause-specific hazard models.   

Results:

During the study period, 9,852 patients with ESRD due to SLE were waitlisted for a renal transplant, and 5,914 (60%) of these patients received a transplant. The majority were female (82.1%) and non-white (59.3%). The average age at ESRD onset, waitlisting, and transplant were 35.7 years, 37.7 years, and 38.5 years, respectively, and the average time from ESRD diagnosis to being waitlisted was 1.5 years. Over a mean follow up time of 7.6 years following waitlisting, 2,722 died. Transplantation was associated with a 67% reduction in overall mortality (HR 0.33 (95% CI 0.29-0.38) among those waitlisted. In cause-specific analyses, patients who remained on the waitlist had a higher risk of cause-specific death from CVD (adjusted HR, 9.2 [95% CI, 7.9-10.7]) cancer (adjusted HR, 3.8 [95% CI, 2.3-6.1]) and infection (adjusted HR, 7.4 [95% CI 5.8-9.3]).

Conclusion:

In this nationwide study of transplantation for ESRD due to SLE, renal transplantation was associated with a 67% reduction in mortality. Patients who were waitlisted but never received a transplant were more likely to die from CVD, cancer, and infection. Our findings highlight the survival benefits associated with renal transplantation for patients with SLE ESRD and call for the need to improve access to transplantation in this patient population. Patients on the waitlist may benefit from improved interventions to minimize CVD, cancer and infection risk.