Objectives: The literature search on kidney transplant procedures performed in Turkey showed that few publications are available about gender distribution and the relationships between living donors and recipients. Therefore, this study aimed to examine the gender distributions and the relationships between donors and recipients of living-donor kidney trans-plants performed in a university hospital in Ankara, Turkey.
Materials and Methods: In this study, we retrospectively analyzed the hospital records of living kidney donors (1611 cases) and all 1991 kidney recipients who under-went living-donor and deceased-donor kidney trans-plant procedures in a university hospital between 1985 and 2017.
Results: In the study hospital, the annual average number of living-donor kidney transplants increased from 19 to 49 cases (total of 1611 cases) per year during the analyzed period. Among them, 57.8% of all kidney donors were female (P < .05), whereas 74.7% of the recipients were male (P < .05). Two-thirds (60.0%; 228/380) of deceased-donor kidney recipients were male. First-degree blood relatives accounted for most of the donors, as the most common donor-recipient relation was mother to son (67.3%; 327/486; P < .05). Interspousal donation also showed a significant difference between husband to wife and vice versa (36 vs 145; P < .05).
Conclusions: There was a male and young predom-inance among recipients and a female and middle-aged predominance among donors of living kidney transplants in this hospital. It is not known whether this might be related to possible differences between males and females in demand of kidneys, to socio-cultural and gender inequalities, or to economic factors. Further research with qualitative components on gender factors should be carried out.
Key words : Donor-recipient relation, Living-donor kidney transplantation, Living kidney recipient
Kidney transplantation is the most successful treatment method to improve the quality of life and the survival of patients with end-stage renal disease. Living-donor kidney transplantation has gained more importance due to insufficiency of deceased organ donations. Donations from living donors save many lives; it is an example of sacrifice, solidarity, and the sincere care for the well-being of others.1 Increased public awareness of renal failure and its treatment by transplantation and the safety of kidney donation, as well as scarcity of organs from deceased donors, have played important roles in the increase of living-related kidney donations.2
Worldwide and in most Western countries, in organ transplants from living kidney donors, there are significant differences in the gender distribution of living donors (two-thirds female) and recipients (two-thirds male). Women mostly donate organs to both women and men, whereas most men give organs to men and most recipients are also male.3-6 Middle Eastern and Eastern countries show a male predominance in donation.2,7-9 This gender difference could be the result of the communities socioeconomic and cultural characteristics and traditional and religious beliefs. When the donor and recipient relationships were examined, it was found that most were blood relatives, and 1 in 10 were spouses.3-6,10,11
Although there is considerable research in the literature, in Turkey, there are few publications about gender distribution and the relationships between living donors and recipients. Therefore, this study aimed to examine the gender distributions and relationships between donors and recipients in living-donor kidney transplant procedures performed in a university hospital in Ankara, Turkey.
Materials and Methods
In this study, we retrospectively analyzed the hospital records of living kidney donors (1611 cases) and all 1991 kidney recipients who received living-donor and deceased-donor kidney transplant procedures in a university hospital between 1985 and 2017. We analyzed data of all kidney transplants performed until December 31, 2017. Information about the number of male and female donors as well as recipients, donor-recipient relationships, and age of individuals at the time of kidney transplant were obtained from the Nucleus Program records used for our Hospital Registration System. The study protocol was approved by the Institutional Review Board.
Statistical analyses were performed with SPSS software (SPSS: An IBM Company, version 25.0, IBM Corporation, Armonk, NY, USA). Descriptive statistics, averages, frequency tables, and dependent-group t tests were used to analyze the variables. Statistical significance was identified by a two-sided P value of < .05.
In our hospital, the annual average number of living-donor kidney transplants increased from 19 to 49 cases (total 1611 cases) per year from 1985 to 2017. Only one-third of all deceased-donor and living-donor kidney donors were female, whereas 71.8% were male. Two thirds (60.0%; 228/380) of deceased-donor kidney recipients were male. Among all living kidney donors, 57.8% of recipients were female (P < .05) and 74.7% of recipients were male (P < .05). The distribution of male to male donations constituted 71.5% (486/680), and the distribution of male to female constituted 28.5% (194/680) (P < .05). Females provided 76.5% (713/931) and 23.4% (218/931) of living kidney donations to males and females, respectively (P < .05). Most males received kidneys from females and donated their kidneys more often to males.
The mean age of recipients was 31.9 ± 12.6 years, and 85.0% (1360/1611) were younger than 44 years old. In addition, 42.2% (680/1611) of all living donors were middle-aged (range, 45-79 y), with an average donor age of 42.1 ± 11.8 years (Table 1). Women more often donated their kidneys to pediatric recipients (13.6% female donors [127/931] vs 9.7% male donors [66/680]; P < .05), whereas men more often donated to elderly (16.8% male donors [114/680] vs 14.7% female donors [137/931]).
Most living donors were blood relatives (87.7%; 1414/1611). Only 10 donors (3 female, 7 male) were nonblood relatives and 6 donors were not relatives (2 female, 4 male). First-degree relatives accounted for most of the donors (76.6%; 1234/1611), and the most common donor-recipient relation was mother to son (26.5%; 327/1234; P < .05). Mothers were more likely to donate than fathers (39.4% vs 20.0%, respectively). Further analyses showed that brothers (178 vs 46; P < .05) and sisters (176 vs 41; P < .05) were giving more frequently to brothers than to sisters. Interspousal donations also showed a significant difference between husband to wife and vice versa donations (36 vs 145; P < .05) (Table 2).
Our study showed that there is an evident gender difference between living donors and their recipients. Females donated more and received fewer kidneys than males (Table 1). Numerous international studies and many from Western countries (including Canada, Norway, India, United States, and Switzerland) have also shown that women constitute the majority of living kidney donors.3-6,10,11 Female donation rates reported by multiple Western renal registries range between 57.0% and 68.0%.3-6 In our hospital, the gender distribution in living-donor kidney transplants was similar to that shown in Western countries. In our study, 57.0% of living kidney donors were female and 74.7% of recipients were male (Table 1). The gender difference was statistically significant (P < .05). These results are similar to the gender distribution of 15 131 living-donor kidney transplants performed between 2008 and 2017 in Turkey, in which 57.3% of living donors were female and 64.9% of recipients were male.12 However, in contrast to that shown in Western countries, in Middle Eastern and Eastern Islamic countries, most living donors and recipients are male.2,7-9 In a study that assessed donor and recipient gender distribution in Saudi Arabia, males donated significantly more than females (67.4% vs 32.6%) and also received more than females.2 Of 16 672 living-donor kidney transplant procedures performed in Iran, 80.0% of living donors and 62.0% of recipients were male.8 Although Turkey is perceived as a Middle Eastern country and most of the population has the same religious beliefs as in those countries, the gender differences among living donors and recipients are not similar. This may be related to its sociocultural similarity to Western countries.
The reason for gender discrepancies is variable and multifactorial and may vary depending on both sociocultural matters and biological determinants. In Western countries, the main reasons for gender disparities in recipients could be the higher incidence of kidney disease in men and fear of losing earnings of male donors and recipients. Female preponderance in living donors could be the result of women’s perception of renal donation as an extension of family responsibilities of women.3-5,8 It was also suggested that social, economic, and gender attitude differences could be responsible.3,4
In our study, we also found that most males (76.5%) received kidneys from females and donated their kidneys more often to males (71.5%). Male to female donation was 28.5%. This also shows similarity with reports from Western countries where women are most likely to donate to men and men are less likely to donate to women.3,6,13 This contrasts again with the rates shown in Middle Eastern and Eastern countries.2,4,5,7 Disparities between findings could be due to divergent cultural and social conditions in different societies. There is also some evidence that men and women have different attitudes toward donation.14,15
In our study, recipients were generally young with a mean age of 31.9 ± 12.6 years and most were younger than 44 years old at the time of transplant. Most living donors were middle-aged with an average donor age of 42.1 ± 11.8 years (Table 1). Compared with Iran, recipients of living-donor kidney transplants in our study were younger and donors were found to be older. The mean age of recipients of living-donor kidney transplants in Iran was 38 ± 16 year, and most donors were less than 35 years old at the time of transplant (mean age of 28 ± 7 years).8 In our study, the gender distribution of donors regarding recipient age was noteworthy. Women donated their kidneys more often to pediatric recipients (P < .05), whereas men donated more often to the elderly. In Norway, both fathers and mothers donated to their young children.5 In Iran, fathers and mothers donated to their children irrespective of age and gender.8
In our hospital, most living donors were blood relatives (87.7%; 1413/1611); only 16 donors were nonblood relatives or were not relatives. According to the Iranian National database and report on gender of donors and recipients, living unrelated donors were much more common than living related donors (84.0% vs 16.0%, respectively).8 For blood-related donors, we found that 76.6% were first-degree relatives and 59.4% were female. Parental donations constituted the major donor source. Mothers were more likely to donate than fathers, and the most common donor-recipient relation was mother to son (P < .05) (Table 2). These findings are similar to findings from other countries. It seems that there is a global predominance for mothers among parental donations.8,10,16 In our study, in transplants between siblings, the percentage of sisters and brothers as donors were similar, but they were giving more frequently to brothers than to sisters (Table 2). In a Norwegian report, sisters were more frequent donors than brothers.5 In addition to that shown in Norway, siblings in the United Kingdom, Switzerland, and Iran constituted the major first-degree blood relative among living donors.4,5,8,17 In our study, interspousal donations showed significant differences between husband to wife and wife to husband; 145 (80.1%) of the donors were females, donating their kidney to their husbands, whereas 36 (19.9%) were males who donated to their wives (P < .05) (Table 2).
Female predominance in spousal donations is also seen worldwide.3,5,6,11,18 In Switzerland, about 73.0% of spousal donations were made by females.4 In Canada, 90.0% of spousal kidney transplants were from wives to husbands.3 Moreover, females comprise more than 68.0% and two-thirds of the American and Norwegian spousal donors, respectively.5,6 This finding could be related to the social expectations for women to donate their kidney as they are perceived as the caregivers of the family.
In conclusion, there was a male and young predominance among recipients and a female and middle-aged one among donors of living-donor kidney transplants in our hospital. Most living donors were first-degree female blood relatives. It is not known whether this might be related to the possible differences between genders regarding biological determinants, sociocultural and gender inequalities, or economic factors. Further research with qualitative components on gender factors should be carried out to determine to what extent these or other factors are contributing.
Volume : 17
Issue : 1
Pages : 246 - 249
DOI : 10.6002/ect.MESOT2018.P109
From Departments of 1Public Health and 2Transplantation, Baskent University,
Acknowledgements: The authors have no conflicts of interest to declare. This work was supported by Research Fund of Baskent University (KA18/64).
Corresponding author: Sare Mıhçıokur, Baskent University Department of Public Health, 79.Sokak (Eski 12.Sokak), No 7/7, Bahçelievler, Ankara, Turkey
Phone: +90 535 276 0977
Table 1. Distribution of Gender and Age of Donors and Recipients in Kidney Transplant Procedures in a Transplant Center (Ankara, Turkey, 1985-2017)
Table 2. Distribution of Gender and Relationships of Donors and Recipients in Living-Donor Kidney Transplant Procedures in a Transplant Center (Ankara, Turkey, 1985-2017)