Several Studies Do Find Women Predominate Among Living Organ Donors
Studies ranging from Germany (1) to Oman (2) find that among medically suited living donors, women tend to donate more than men.
Kidney:
In 2005, 59.2% of living US kidney donors were women while 58.2% of
kidney recipients were men (3). Predominance of female kidney donors is
seen not just in the US but also in Brazil (4).
Global estimates for living kidney donors is ~65% female with ~65% of
kidney recipients being male (3). Spousal differences are more striking
compared to generic estimates. A University of Michigan study found 69%
of spousal donations were female (5).
Liver:
In 2005, 58.3% of living US liver donors were women while 58% of living
liver segment recipients were men (6). Again, spousal differences are
more striking compared to generic estimates. A Canadian study found 36%
of women suitable for donating to their husbands were willing to do so
while only 6.5% of suitable husbands were willing to be donors for their
wives (7).
Examination of published literature suggests a combination of
- Different solid organ disease prevalence rates between men and women,
- Greater cultural pressure on women to carry the burden of caregiving,
- Gender selection bias in the healthcare system,
all of these factors contribute to why women predominate in living organ donations and yet receive fewer organ transplants.
Different solid organ disease prevalence rates between men and women
Several
studies have documented pronounced gender bias in transplantation.
However, while examining these, onus is on us to account for
gender-based disease prevalence rate differences, especially where the
rates are higher in men.
Kidney: Renal
disease tends to be more common in men compared to women (8). Mortality
rates of men on dialysis is also higher compared to women (9).
Speculation is baseline creatinine clearance is better in elderly women
compared to men.
Heart: In 1996, 81.2%
of US heart transplant recipients were men and this only decreased to
76.8% by 2005 (6). Part of this has to do with greater preponderance of
coronary artery disease in young men compared to young women. Even among
those aged 55 to 64 years, congestive heart disease rates in US men are
twice those in women.
Liver: Liver disease rates are higher among US men (10).
Greater cultural pressure on women to carry the burden of caregiving
Studies
suggest women may offer kidneys more often from a greater drive to
alleviate suffering and/or a greater inability to resist subtle
pressures (11). Some authors speculate preponderance of bearing the
burden of caregiving in a family may extend the woman's role to becoming
a living kidney donor (12). Some studies support this conclusion (13).
In fact, women are considered more vulnerable and more easily
persuaded/pressured to donate (14). This is the reason the
multi-disciplinary living donor assessment process in Australia and the
US focuses on the living kidney donor's autonomy and decision making in
the absence of coercion (15). Cultural differences may also play a role.
Even today, in many societies the woman is the main caregiver with the
man the breadwinner. When a woman undergoes transplantation, the man
would need to take time off work to take over household management. Some
authors (3, 12) speculate transplant centers may inadvertently
reinforce such gender roles in the manner they offer, discuss and foster
women's access to transplantation.
Gender selection bias in the healthcare system
Studies find men are often preferentially placed on transplant waiting lists (16, 17).
Kidney:
A French study on 9497 men and 5386 women on dialysis found that women
had both a lower probability of being registered on the waiting list and
waited longer after starting dialysis before being registered (18).
This study found older, unemployed and diabetic women were more likely
to be victims of such disparities. A large southeastern US study found
women were less likely to be perceived suitable for kidney transplants
compared to men, and this was independent of medical factors (19). Gender bias favoring men was found in other US studies as well (20, 21).
Heart:
Of US heart transplants in 2005, 52.3% of heart transplant recipients
in 2005 were aged 50 to 64 years and 10.3% >65 years. With age,
especially >65 years, coronary artery disease rates between US men
and women are similar (22). Yet, gender bias persists even among this
older age group of heart transplant recipients (3). Studies show that
women decline heart transplantation at greater rates compared to men (23). One reason proffered for this implies surgeons prioritizing vanity over vocation,
i.e., women presented with this option in a manner inclined to
discourage them for the simple reason that post-transplant mortality
rates tend to be higher for women compared to men, and heart transplant
surgeons may be motivated by concern for their success rates (3).
Liver:
One US study found women were less likely to get liver transplants (24)
while another one found twice as many men as women get liver
transplants (25) even though disease rates aren't twice higher.
According to JoAnn Grif Alspach (26),
gender bias in medical care can thus be the unintentional product of
implicit, insidious bias in the culture of medicine itself. She then
lists the following implicit cultural biases as possible reasons,
'• Underestimating or misunderstanding a woman’s risk for health problems or complications 8• Differences in the way women experience (cardiac) symptoms 30• Differences in the way women perceive themselves and their illness 30• The most likely explanations are at the patient level, the physician level, or both. Patients may have misperceptions of indications, risks, or benefits of surgery.• One factor may be the differences in style that women and men use to describe their symptoms or injuries to the physician. Women tend to describe what they experience as a more personal, narrative commentary compared to men, who typically describe symptoms in a more straightforward, factual manner with fewer comments. 49 Women’s narrative presentation style reportedly contributed to physicians making more diagnostic errors in their evaluations of chest pain in women. 50• Unconscious prejudices among physicians—social stereotyping 29• Overt discrimination based on sex. Some physicians take women’s symptoms less seriously, attribute symptoms to emotional rather than physical causes, and refer women less often than men for specialty care, even women with a relatively greater degree of disability. 29• Cultural biases, especially among older male physicians 51• Women thinking of stroke and heart disease as men’s diseases 51• Perceived differences in injury severity or perceived benefits of trauma center care, or from subconscious gender bias 48'
Ironically, transplants in women have also often been pioneering.
- In August 1966, Dr. Michael E. DeBakey implanted the 1st extracorporeal left ventricular assist device in a 37-year old woman who couldn't be weaned from bypass following a double valve replacement (27). The pump was successfully removed after 6 days and she survived for 6 years with good cardiac function only to tragically die from an automobile accident.
- The 1st pancreas allograft occurred on December 17, 1966 at the University of Minnesota when Drs. William Kelly and Richard Lillehei simultaneously transplanted a kidney allograft plus a duct ligated segmental pancreas into a 28 year old woman (28).
Gender Bias Matters Medically Because Gender Mismatch In Transplants Is Often Counter-Productive
Gender mismatch between donors and recipients is often counter-productive.
Specifically, men with allografts from women have greatest risk of
long-term allograft failure (29). This is especially true for kidney
transplants (30). Risk also runs both ways. In donations after
circulatory/cardiac death (DCD), transplanting a male liver into a
female recipient is a risk factor for primary non-function (31).
Female recipients of male hearts is a risk factor for acute cellular
and antibody-mediated rejection of heart transplants (32, 33, 34, 35,
36). Studies suggest gender matching may protect against heart
transplant rejection (37).
Bibliography
1. Decker, Oliver, et al. "Between commodification and altruism: gender
imbalance and attitudes towards organ donation. A representative survey
of the German community." (2008): 251-255.
2.
Mohsin, N., et al. "Donor gender balance in a living-related kidney
transplantation program in Oman." Transplantation proceedings. Vol. 39.
No. 4. Elsevier, 2007.
3. Csete, Marie. "Gender issues in transplantation." Anesthesia & Analgesia 107.1 (2008): 232-238.
4. Lima, Daniel Xavier, Andy Petroianu, and Heather Lynn Hauter.
"Quality of life and surgical complications of kidney donors in the late
post-operative period in Brazil." Nephrology Dialysis Transplantation
21.11 (2006): 3238-3242. Quality of life and surgical complications of kidney donors in the late post-operative period in Brazil
5. Kayler, Liise K., et al. "GENDER IMBALANCE IN LIVING DONOR RENAL TRANSPLANTATION1." Transplantation 73.2 (2002): 248-252.
6. US Department of Health and Human Services. "2008 Annual Report of
the US Organ Procurement and Transplantation Network and the Scientific
Registry of Transplant Recipients: Transplant Data 1998-2007." (2008).
7. Zimmerman, Deborah, et al. "Gender disparity in living renal
transplant donation." American Journal of Kidney Diseases 36.3 (2000):
534-540.
8. Reyes, Daisy, Susie Q. Lew, and
Paul L. Kimmel. "Gender differences in hypertension and kidney disease."
Medical Clinics of North America 89.3 (2005): 613-630.
9. Lindeman, Robert D., Jordan Tobin, and Nathan W. Shock.
"Longitudinal studies on the rate of decline in renal function with
age." Journal of the American Geriatrics Society 33.4 (1985): 278-285.
10. Kim, W., et al. "Burden of liver disease in the United States: summary of a workshop." Hepatology 36.1 (2002): 227-242. https://www250.safesecure
11. Biller-Andorno, Nikola. "Gender imbalance in living organ
donation." Medicine, Health Care and Philosophy 5.2 (2002): 199-203.
12. Gordon, Elisa J., and Daniela P. Ladner. "Gender inequities pervade
organ transplantation access." Transplantation 94.5 (2012): 447-448. https://www.researchgate.
13. Mohs, Anja, and Gundula Hübner. "Organ donation: the role of gender
in the attitude–behavior relationship." Journal of Applied Social
Psychology 43.S1 (2013): E64-E70. https://www.researchgate.
14. Dobson, Roger. "More women than men become living organ donors." BMJ: British Medical Journal 325.7369 (2002): 851.
15. Spital, Aaron. "Ethical issues in living organ donation: donor
autonomy and beyond." American Journal of Kidney Diseases 38.1 (2001):
189-195.
16. Alexander, G. Caleb, and Ashwini
R. Sehgal. "Barriers to cadaveric renal transplantation among blacks,
women, and the poor." Jama 280.13 (1998): 1148-1152. http://citeseerx.ist.psu.
17. Bayat, S., et al. "Individual and regional factors of access to the
renal transplant waiting list in France in a cohort of dialyzed
patients." American Journal of Transplantation 15.4 (2015): 1050-1060.
18. Couchoud, Cécile, et al. "A new approach for measuring gender
disparity in access to renal transplantation waiting lists."
Transplantation 94.5 (2012): 513-519.
19.
Soucie, J. Michael, John F. Neylan, and William McClellan. "Race and sex
differences in the identification of candidates for renal
transplantation." American journal of kidney diseases 19.5 (1992):
414-419.
20. Thamer, Mae, et al. "US
NEPHROLOGISTS’ATTITUDES TOWARDS RENAL TRANSPLANTATION: RESULTS FROM A
NATIONAL SURVEY." Transplantation 71.2 (2001): 281-288. https://www.researchgate.
21. Segev, Dorry L., et al. "Age and comorbidities are effect modifiers
of gender disparities in renal transplantation." Journal of the
American Society of Nephrology 20.3 (2009): 621-628. Age and Comorbidities Are Effect Modifiers of Gender Disparities in Renal Transplantation
22. Young, Lynne, and Maureen Little. "Women and heart transplantation:
an issue of gender equity?." Health care for women international 25.5
(2004): 436-453.
23. Aaronson, Keith D., et
al. "Sex differences in patient acceptance of cardiac transplant
candidacy." Circulation 91.11 (1995): 2753-2761. Sex Differences in Patient Acceptance of Cardiac Transplant Candidacy
24. Myers, Robert P., et al. "Gender, renal function, and outcomes on
the liver transplant waiting list: assessment of revised MELD including
estimated glomerular filtration rate." Journal of hepatology 54.3
(2011): 462-470.
25. Thuluvath, P. J., et al.
"Liver transplantation in the United States, 1999–2008." American
Journal of Transplantation 10.4p2 (2010): 1003-1019. https://deepblue.lib.umic
26. Alspach, JoAnn Grif. "Is there gender bias in critical care?." Critical care nurse 32.6 (2012): 8-14. Is There Gender Bias in Critical Care?
27. DeBakey, Michael E. "Left ventricular bypass pump for cardiac
assistance: clinical experience." The American journal of cardiology
27.1 (1971): 3-11.
28. Kelly, W. D., et al.
"Allotransplantation of the pancreas and duodenum along with the kidney
in diabetic nephropathy." Surgery 61.6 (1967): 827-837.
29. Kittleson, Michelle M., et al. "Donor–recipient sex mismatch
portends poor 10-year outcomes in a single-center experience." The
Journal of Heart and Lung Transplantation 30.9 (2011): 1018-1022.
30. Gratwohl, Alois, et al. "HY as a minor histocompatibility antigen
in kidney transplantation: a retrospective cohort study." The Lancet
372.9632 (2008): 49-53.
31. De Vera, M. E., et
al. "Liver Transplantation Using Donation After Cardiac Death Donors:
Long‐Term Follow‐Up from a Single Center." American Journal of
Transplantation 9.4 (2009): 773-781. http://www.custodiol.com/
32. Kobashigawa, J. A., et al. "Pretransplantation risk factors for
acute rejection after heart transplantation: a multiinstitutional study.
The Transplant Cardiologists Research Database Group." The Journal of
heart and lung transplantation: the official publication of the
International Society for Heart Transplantation 12.3 (1992): 355-366.
33. Jarcho, J., et al. "Influence of HLA mismatch on rejection after
heart transplantation: a multiinstitutional study. The Cardiac
Transplant Research Database Group." The Journal of heart and lung
transplantation: the official publication of the International Society
for Heart Transplantation 13.4 (1993): 583-95.
34. Lones, Mark A., et al. "Clinical-pathologic features of humoral
rejection in cardiac allografts: a study in 81 consecutive patients."
The Journal of heart and lung transplantation: the official publication
of the International Society for Heart Transplantation 14.1 Pt 1 (1994):
151-162.
35. Kubo, S. H., et al. "Risk
factors for late recurrent rejection after heart transplantation: a
multiinstitutional, multivariable analysis. Cardiac Transplant Research
Database Group." The Journal of heart and lung transplantation: the
official publication of the International Society for Heart
Transplantation 14.3 (1994): 409-418.
36.
Michaels, Paul J., et al. "Humoral rejection in cardiac transplantation:
risk factors, hemodynamic consequences and relationship to transplant
coronary artery disease." The Journal of heart and lung transplantation
22.1 (2003): 58-69.
37. Patel, Nishant D., et
al. "Impact of donor-to-recipient weight ratio on survival after heart
transplantation analysis of the United Network for Organ Sharing
database." Circulation 118.14 suppl 1 (2008): S83-S88. Impact of Donor-to-Recipient Weight Ratio on Survival After Heart Transplantation
https://www.quora.com/Why-do-women-make-up-a-majority-of-live-organ-donors-but-not-of-organ-recipients/answer/Tirumalai-Kamala
