They don't do well, do they? Survival of propensity matched Indigenous transplant & dialysis patients

Aim: To compare survival for Indigenous transplant patients with similar Indigenous dialysis-only patients, contrasting with non-Indigenous patients.

Background: Indigenous patients are less likely than non-Indigenous to be waitlisted for or receive a kidney transplant. Some clinicians are concerned about Indigenous transplant outcomes.

Methods: Using ANZDATA, all Australian patients commencing renal replacement therapy from 1st April 1995 to 31st December 2009 were included and followed until 31st December 2012. Transplant recipients were paired by propensity score (using age, sex, late referral, comorbidities and remoteness) with similar dialysis-only patients of the same ethnicity for three time cohorts (1995–1999, 2000–2004, 2005–2009); time at risk for each pair was taken from the transplant date. Five year all-cause survival differences were measured using the log–rank test and Cox proportional hazards models adjusted for demographic and clinical differences and a transplanted-remoteness interaction term.

Results: Proportionally fewer Indigenous than non-Indigenous patients were transplanted. Indigenous dialysis-only patients were similar to their transplanted pair at baseline, but paired non-Indigenous patients were less similar. Unadjusted analysis (using log–rank tests) showed better survival of transplanted patients than their dialysis-only pair for both non-Indigenous (p < 0.001) and Indigenous patients (p = 0.002). Adjusted Cox models comparing transplantation with dialysis-only patients showed that in major capital cities (MC) hazard ratios (HR, with 95% CIs) were similar for non-Indigenous (HR 0.18 (0.15–0.22)) and Indigenous (HR 0.23 (0.08–0.69)) patients. Among Indigenous patients, HRs were higher in remote regions (RR HR 0.69 (0.28–1.71)) than MC, but similar everywhere for non-Indigenous patients (RR HR 0.11 (0.03–0.48)).

Conclusions: Indigenous transplanted patients have better survival than similar dialysis-only patients, especially in MC, but relatively fewer suitable Indigenous patients are transplanted, raising important questions about the equity–utility balance.