Socioeconomic Status Impacts Pediatric Preemptive Kidney Transplant Rates, Study Finds

Findings from a recent study are calling attention to significant socioeconomic disparities in preemptive kidney transplantation rates among pediatric patients.1

The retrospective cohort study leveraged data for pediatric kidney transplant recipients who were transplanted at the University of Minnesota and found lower HOUsingbased index of Socio-Economic Status (HOUSES) index quartile was associated with significantly reduced odds of preemptive transplantation.1

Kidney transplantation is the treatment of choice for children with end-stage kidney disease (ESKD). While the 2020 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guidelines recommend preemptive transplantation for all children with advanced chronic kidney disease, in 2021, just 24.2% of children with incident ESKD received a preemptive transplant in the United States.2,3

“Social deprivation, public insurance, a minority race/ethnicity, and low educational attainment are associated with a lower likelihood of a preemptive transplant and a higher likelihood of longer pretransplant dialysis exposure,” Sarah Kizilbash, MBBS, MS, an associate professor and director of the division of pediatric nephrology at the University of Minnesota, and colleagues wrote.1 “Pediatric data on the effects of socioeconomic factors on preemptive transplantation are sparse and conflicting.”

To determine the differential effect of individual-level socioeconomic status on preemptive kidney transplantation in children, investigators conducted a retrospective cohort study using data from a prospectively maintained, IRB-approved, solid organ transplant database at the University of Minnesota. From this database, they identified all pediatric kidney transplant recipients < 18 years of age at the time of transplant who were transplanted between January 2010 and January 2020.1

To overcome the limitations of the existing socioeconomic status measures, investigators used the novel HOUSES index, an individual-level socioeconomic status measure generated by linking address information from electronic health records or other data sources to publicly available real property data. It is computed from 4 variables based on the recipient’s residential address: the number of bedrooms, the number of bathrooms, the square footage of the unit, and the estimated building value of the unit. Investigators divided HOUSES index scores into quartiles, with Q1 indicating the lowest socioeconomic status.1

The primary outcome of interest was preemptive transplantation, defined as transplant before dialysis. The secondary outcome was dichotomized pretransplant dialysis duration, categorized as <1 year or ≥ 1 year.1

The final analytical cohort included 173 pediatric kidney transplant recipients who were predominantly male (54.9%) and White (72.8%). Overall, the median age at ESKD was 11.4 (range, 0.01-17.9) years and the median age at transplant was 12.2 (range, 0.77-19.6) years.1

Preemptive transplantation was observed in 46 (26.6%) recipients, while pretransplant dialysis was noted in 127 (73.4%) recipients.1

Compared with patients in Q2-Q4, investigators noted Q1 recipients were less likely to have undergone a preemptive transplant (13.6% vs 31.0%; P = .02). Additionally, they pointed out the preemptive transplant group included a greater number of male recipients (71.7% vs 48.8%; P = .007), privately insured recipients (78.3% vs 53.5%; P = .003), and Q2-Q4 recipients (87.0% vs 70.1%; P = .024) compared with the non-preemptive group.1

After adjusting for age at ESKD, sex, donor type, insurance type, and the cause of ESKD, investigators observed significantly reduced odds of preemptive transplantation for Q1 recipients compared with Q2-Q4 recipients (adjusted odds ratio [aOR], 0.31; 95% CI, 0.11-0.90; P = .03). Additionally, they found age at ESKD, sex, and the cause of ESKD were significant predictors of preemptive transplantation.1

Further analysis revealed a greater proportion of Q1 recipients received pretransplant dialysis for >1 year than Q2-Q4 recipients, although investigators noted the difference did not achieve statistical significance (47.2% vs 30.1%; P = .08). After adjusting for age at ESKD, race, donor type, and insurance type, they observed no significant effect of the HOUSES index on pretransplant dialysis duration.1

“The findings underscore the need for targeted interventions to overcome socioeconomic barriers to timely transplantation,” investigators concluded.1 “Early referral for transplant evaluation, timely listing, and resource allocation guided by HOUSES may be effective strategies to mitigate disparities.”

References

1. Kizilbash S, Wi CI, Roy M, et al. Socioeconomic Disparities in Preemptive Kidney Transplant Rates in Children. Kidney360. doi:10.34067/KID.0000000802.

2. Chadban SJ, Ahn C, Axelrod DA, et al. KDIGO Clinical Practice Guideline on the Evaluation and Management of Candidates for Kidney Transplantation. Transplantation. doi:10.1097/TP.0000000000003136

3. United States Renal Data System. 2023 USRDS Annual Data Report: Epidemiology of kidney disease in the United States. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases. https://usrds-adr.niddk.nih.gov/2023