Effect of a strict HLA matching policy on distribution of cadaveric kidney transplants to Indo-Asian and white European recipients: regional studyBMJ 1997; 315 doi: https://doi.org/10.1136/bmj.315.7119.1354 (Published 22 November 1997) Cite this as: BMJ 1997;315:1354
- R M Higgins, consultant physician ()a,
- N West, transplant coordinatora,
- M E Edmunds, consultant physiciana,
- D C Dukes, consultant physiciana,
- H Kashi, consultant surgeona,
- A Jurewicz, consultant surgeona,
- F T Lam, consultant surgeona
- Correspondence to: Dr Higgins
- Accepted 10 April 1997
The matching of donor and recipient for HLA type is an important factor in determining the survival of kidney grafts.1 Our unit participates in national and regional organ sharing schemes and allocates locally donated kidneys according to HLA matching. Consequently only 2% of our transplants have had two mismatches for HLA-DR. This policy could put patients whose HLA types differ from those in the donor population at a disadvantage.2
In this study we measured the rates of end stage renal failure, kidney donation from cadavers, and kidney transplantation in the white European and Indo-Asian populations of Coventry and Warwickshire.
Patients, methods, and results
Data on the adult population in Coventry and Warwickshire were obtained from the 1991 national census. Patient records from 1988 to 1995 inclusive were examined to determine the patient's place of residence. The ethnic group of patients was identified by surname and by the ethnic group declared at the time of registration at the hospital. We included only Indo-Asian and white European patients in the study. The definition of beneficial HLA matching was that used by the United Kingdom Transplant Support Service Authority. Statistical analysis was by the χ2 test and Student's t-test as appropriate.
No difference was seen between the proportions or ages of white European and Indo-Asian patients receiving dialysis who were placed on a waiting list for transplant surgery (1). Thirty three per cent (17/51) of Indo-Asian patients and 19% (48/254) of white European patients remained on waiting lists for more than 2 years without receiving a transplant (P<0.025). The rate of organ donation was considerably lower in the Indo-Asian population than in the white European population: 40.1 kidneys donated per million population per year among white Europeans compared with 9.3 among Indo-Asians.
As expected, the Indo-Asian patients had a different distribution of blood groups—a higher frequency of groups B and AB and a lower frequency of group A. The proportion of Indo-Asian patients in each blood group who received transplants was lower than the proportion of white Europeans; this difference was most obvious for blood group O, in which 63 out of 117 (54%) white Europeans received transplants compared with 2 out of 14 (14%) Indo-Asian patients.
Our results confirm that proportionately more Indo-Asian patients than white European patients both start dialysis and wait for a kidney transplant.3 Our policy for the distribution of grafts resulted in similar proportions in each ethnic group receiving grafts beneficially matched for HLA: 22% of white Europeans and 14% of Indo-Asians. Therefore, our results do not seem to be caused by bias in the selection of patients for transplantation or in the distribution of grafts.
We believe that Indo-Asian patients should not be denied access to renal transplantation because there is a low rate of organ donation from their ethnic group. The factors that may account for the low rate of donation among Indo-Asian patients include the age distribution of the Indo-Asian population, the low number of Indo-Asians admitted to intensive care units, and religious views about organ donations from cadavers.
So long as organs for transplantation are scarce, a strong argument can be made for the allocation of kidneys solely to achieve the best possible graft survival; this is the current policy used by the United Kingdom Transplant Support Services Authority. This is also the policy that we have used previously.
Since June 1996, after the end of our study, we have altered our policy for the allocation of kidneys: regardless of ethnic origin all patients who have been on the waiting list for more than 2 years may be offered a kidney on the basis of a HLA-DR0 or HLA-DR1 match whatever the HLA class 1 matching (as long as the HLA-A2 and the HLA-B5 group are not mismatched). In this way we hope to improve access to transplantation while maintaining some advantage from HLA matching.
Conflict of interest: None.