Sex imbalances in kidney transplants in Iran

Kidney transplantation is generally considered the treatment of choice for end-stage renal patients who require renal replacement therapy (1). Renal transplantation from deceased donors is the most ethical and preferred method of kidney transplantation for treating end-stage renal failure. However, as the method becomes more widely used, a shortage of kidneys for transplant is growing. Since December 23, 1954, when the first kidney transplantation from a living donor was performed in the US between identical twins, this method has become increasingly common as a way to address the gap between demand and supply for kidney transplants worldwide.

Discussions on the sale of organs are overshadowed by reports of coercion and exploitation. It is also argued that organ markets reduce transplantation from cadaveric sources and altruistic donation.

A number of studies from all different countries have reported the existence of a profound sex imbalance among kidney recipients and living donors; men are in the majority among kidney recipients but women constitute the predominant source for living kidney donations, both in industrialised and non-industrialised countries (2, 3, 4, 5, 6, 7, 8, 9). At least one author has stated that this is true for the kidney transplantation programme in Iran as well (3).

The reasons behind these disparities remain obscure. Economic and cultural factors may contribute to gender disparity, especially among living unrelated kidney donations (LURD) (4). We looked at sex differences between recipients and living unrelated donors in what is termed as “the Iran model of kidney transplantation” (1, 5).

All kidney transplants performed from a living unrelated kidney donor from 1992 to 2006 at Baqiyatallah hospital, a university-based kidney transplantation centre and a major transplantation centre in West Asia, were included in the study. We analysed the sex distribution of our LURD donors and recipients.

A total of 2,414 kidney transplants were conducted at our centre. Of these, 2,172 were from a living unrelated donor. The sex of 1,947 (85.4 per cent) of our LURD kidney donors was reliably documented in our data registry: 1,679 (86 per cent) were male and 268 (14 per cent) were female. Of the 2,172 kidney recipients, 1,397 (64.3 per cent) were male and 851 (35.3 per cent) were female.

The term “Iran model of kidney transplantations” refers to a government-controlled and compensated living unrelated kidney donation programme that has been in operation in Iran since 1988. Volunteers who are willing to donate register at the Society for Supporting Dialysis and Transplantation Patients, a liaison agency between potential donors and recipients. They then undergo various evaluations. The donor is paid a reward from government funds and may receive a gift from the recipient as well. Foreigners may not come into this programme, though they may undergo kidney transplantation from a non-Iranian kidney donor (1).

A number of previous studies suggest that kidney allograft from a male donor represents higher survival and lower rejection episodes compared with kidneys donated by females (10, 11). However, studies from different parts of the world document that women constitute the majority of living kidney donors despite the fact that men are more likely to receive a kidney allograft. This imbalance is more prominent in developing countries (4), though developed countries such as Norway (2) Canada (6), USA (7, 8) and Switzerland (9) also have documented female predominance in living kidney donation.

The reason for these discrepancies is not fully explained. It is possible that such disparity among living kidney donors may reflect coercion, a higher proportion of donations from wives to husbands (compared to from husbands to wives), and a higher priority given to the health of the man for his income-earning role in the family (2, 4, 6). Simmons et al reported that a significant number of potential donors experienced direct or indirect pressure to donate, although this was not communicated to the medical staff (12).

The sex distribution in our kidney transplant recipient population is comparable with other parts of the world and may reflect the higher proportion of males with end-stage renal disease compared to females (4, 5, 6, 7, 8). However, in contrast with reports from almost all over the world, we also noticed a different sex distribution among our living kidney donors.

The reason for such a difference is unclear. The unique LURD renal transplantation programme of Iran may provide an explanation. Because of the incentives paid to living unrelated donors by the government (as well as the gift from the recipient), kidney donation may be a more attractive option for men than for women. As the income earners of families, men are more likely to be potential donors for a compensated kidney donation. Moreover, in Iranian culture the man as the family head will not agree to let his wife to donate her kidney for a reward because it is a social taboo. Finally, surgical scars are not acceptable, especially for young girls. Our data may suggest that in Iran there is no coercion on females to donate a kidney to an unrelated recipient.