Research Feature: Impact of living donation on women’s access to liver transplantation
Did you know?
- Living liver donations accounted for 21% (1 in 5) of the estimated 36,000 liver transplants performed in WHO member countries in 2019. (Source)
- In Canada, 1 in every 8 liver transplants is made possible by a living liver donor. (Source)
- Two-thirds of Canadian living donors are women. (Source)
In August, Dr. Mamatha Bhat and team published their latest work Sex Disparity in Liver Transplant and Access to Living Donation in JAMA Surgery. It is known that women are disadvantaged in their access to deceased donor liver transplants, and their study examined whether living donation could help remedy this inequity. We caught up with Mamatha to find out more.
“As a transplant hepatologist looking after patients, I was interested in examining how access to living donor liver transplantation in a program impacted sex disparities on the waiting list.”
How do you think the research will advance the field?
The MELD Na score was transformational in decreasing overall waitlist mortality. However, over time, we have realized that there are certain subgroups that are disadvantaged by this score. For women, the disadvantage is multifactorial. Firstly, the MELD Na in women appears to underrepresent the degree of illness. Specifically, the creatinine in women tends to be lower due to lower muscle mass, and the sodium is also underreflected. Women with cholestatic liver disease such as PBC and PSC are also disadvantaged, due to the bilirubin being underweighted in the MELD Na score.
Beyond prioritization, organ allocation depends on the match between the donor and recipient liver. Most deceased donor organs are from male donors, which could be a disadvantage to women with smaller bodies. A study by Locket et al in JAMA Surgery, 2020 confirmed that women were 14.4% less likely to receive a deceased organ compared to men, having accounted for geographic location, MELD score, and candidate anthropometric and liver measurements.
In our study, we confirmed that living donor liver transplantation is helpful to all patients (both women and men) on the waiting list, regardless of their clinical characteristics. Beyond this, we discovered that as a program performing living donor liver transplants, we can alleviate sex disparity on the waiting list. In fact, using competing risk analysis, we found that women benefited from access to living donor liver transplantation 1.38 times more than men.
Where should the research go from here?
Various studies have looked into how sex disparity on the waiting list could be rectified. However, none of the adjustments for factors such as GFR and liver volume have been able to rectify this disparity. Therefore, this is a very complex problem with no simple solution, given the number of variables involved and dynamics on the waiting list.
I feel that we should be developing a new prioritization and decreased donor organ allocation system that is responsive to the evolving clinical characteristics of waitlisted patients. It is likely that the optimal prioritization would vary based on the unique considerations of each jurisdiction in terms of indication for transplant and supply:demand mismatch. Until such time as we develop a more optimal and equitable prioritization and allocation system, living donation could be considered particularly if there is a substantial mismatch between organ supply and demand in a particular jurisdiction.
The CDTRP is proud to be supporting Dr. Bhat’s work through 2016 and 2018 Research Innovation Grants, funded in partnership with University Health Network.
You can find Mamatha on Twitter @MamathaBhat3 and as co-lead of CDTRP Research Theme 4: Tailor an Optimal Immune System for Each Patient.
ity of Alberta and has received training in patient-oriented research through the University of Calgary’s PACER (Patient and Community Engagement Research) Program. He is the Patient, Family, and Donor Partnerships & Education Manager with the Canadian Donation and Transplantation Research Program. In this role, Manuel builds relationships patient partners with investigators and strengthens capacity among CDTRP patient partners.
Anders Billström 
Gareth Wiltshire
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Sherrie Logan 
born and raised in Edmonton, AB. With a degree in Music Performance (saxophone performance) and Education, Lindsey has taught for over a decade in the Edmonton Public School system. When she is not teaching, she is very involved in the music community, performing in the Edmonton Winds, conducting her own community ensemble (The Beer League Band) and on numerous musical boards across the province. For the past 5 years, Lindsey has had to take a break from teaching after having her amazing son, George. Maternity leave did not goes as expected as George was diagnosed with Dilated Cardiomyopathy at 5 months old and required 2 heart transplants before the age of 4. During this time, Lindsey has also began to dedicate her time building and expanding her charity: Big Gifts for Little Lives, where they raise money to fund Pediatric Heart Transplant research at the Stollery.
Dr. Caigan Du is a scientist at the Vancouver Coastal Health Research Institute and an assistant professor in the Department of Urologic Sciences at the University of British Columbia. He received a Ph.D. degree in Biochemistry in UK and postdoctoral training in Immunology in USA. He is interested in the pathogenesis of kidney ischemia-reperfusion injury and transplant rejection, and molecular control of urinary malignancies. He has been studying the impact of kidney donor-derived factors on renal allograft rejection, and the molecular pathways of kidney injury and regeneration in experimental models. He is also interested in developing medical solution including drugs made from natural compounds for all kinds of health problems, including immune disorders, organ preservation, kidney failure and urinary cancer. He is the PI of many grant supports from the Kidney Foundation of Canada and the Canadian Institutes of Health Research.
Heather Badenoch is a non-directed living liver donor and communications strategist. As the president of Village PR, she provides strategic communications direction and training to not-for-profit clients in community and health. An active transplant volunteer, Heather helps transplant candidates find living donors by running their public appeals, small and large, pro-bono. She also mentors potential living donors on the path to living donation. Heather is a volunteer with the UHN Centre for Living Organ Donation and the Canadian Donation and Transplant Research Program. She and her spouse adopt rescue dogs and volunteer together with Community Veterinary Outreach, a group providing free veterinary care to the pets of people who are homeless.
Sean Dicks is a clinical psychologist who has 20 years’ experience supporting both families of organ donors and transplant recipients. While it is rare for him to have contact with a donor family and recipient linked to the same organ donation-transplantation event, his contact with families who have lived experience with organ donation on the one hand, and patients who have received transplants on the other hand has provided opportunities to explore how their journeys become linked when they attempt to make sense of and find meaning in their respective crises.
Terri Hansen-Gardiner is a Cree speaking Metis woman from Northern Saskatchewan as well as a 10 year Breast Cancer Survivor. Her tireless spirit and dedication to her community is undeniable. Terri is a cancer survivor who travels around the province to provide assistance, information, and support to Indigenous patients who are trying to access and navigate the cancer care system.
Dr. Golnaz Karoubi is Assistant Scientist at the Toronto General HospitalResearch Institute and principal investigator in the Latner Thoracic Research Labs. She currently holds an Assistant Professor appointment in the department of Laboratory Medicine and Pathobiology and a cross-appointment in the department of Mechanical and Industrial Engineering at the University of Toronto. Dr. Karoubi received her PhD in Applied Science and Engineering at the University of Toronto and joined the Lung Regenerative Medicine Program in the Department of Clinical Research in Berne University, Switzerland for a post-doctoral research fellowship. She stayed on as a Group Leader in 2008 to direct the basic and transitional science as related to Cancer Stem Cell and Lung Regenerative Medicine in the Department of Biomedical Research at the University of Berne until 2012. In early 2012, she joined the team of Dr. Tom Waddell at the Toronto General Hospital Research Institute as a Senior Scientific Associate and was appointed to Assistant Scientist at the Toronto General Hospital Research Institute (University Health Network) in November 2019 and to Assistant Professor in the Department of Laboratory Medicine and Pathobiology in July 2020.
Dr. Haykal graduated from the University of Ottawa Faculty of Medicine in2007 as class valedictorian and silver medalist, and subsequently completed her residency training in Plastic and Reconstructive Surgery at the University of Toronto in 2016. During her residency, she completed a four-year Doctorate of Philosophy (PhD) in tissue engineering, regenerative medicine and immunology with a focus on tracheal reconstruction. She obtained numerous grants and awards including a CIHR Vanier Scholarship. Dr. Haykal then pursued fellowship training in microsurgical reconstruction at the Albany Medical Centre in New York. Dr. Haykal joined the University Health Network and the Toronto General Hospital in 2018. Her clinical focus is on complex oncological reconstruction and microsurgical reconstruction of the breast, head and neck and extremity. She started a lymphedema program in 2019 where she offers microsurgical techniques for the treatment of lymphedema.
Dr. Ahmed is a Professor in the Cumming School of Medicine at the University of Calgary. The recipient of the 2022 Hypertension Canada Senior Investigator Award, she is a nephrologist and clinician-scientist with a focus on sex and gender differences in human cardiovascular/kidney physiology and clinical outcomes. Dr. Ahmed is the Vice Chair (Research) for the Department of Medicine, Lead of the Libin Institute Women’s Cardiovascular Health Research Initiative at the University of Calgary and Lead of the Alberta Strategy for Patient Oriented Research Capacity Development Platform. Dr. Ahmed is an Advisory Board member for the Canadian Institutes of Health Research Institute of Gender and Health, a member of the Canadian Medical Association Journal Governing Council and the President-Elect for the Organization for the Study of Sex Differences.
r. Christopher Nguan is an Associate Professor at the University of British Columbia in the Department of Urological Sciences, Surgical Head of Kidney Transplantation at Vancouver General Hospital and the Director of the Surgical Technologies Experimental Laboratory & Advanced Robotics (STELLAR) facility at Vancouver General Hospital.
r Caroline Lamarche is a clinician scientist and transplant nephrologist at Maisonneuve-Rosemont Hospital. She is an assistant clinical professor at the Université de Montréal. After her nephrology training at the Université de Montréal (2015), she completed a Master degree on the use of adoptive immunotherapy to treat/prevent BK nephropathy in kidney transplant recipients. She then pursued a post-doctoral fellowship with Dr. Megan Levings at the University of British Columbia on the use of chimeric antigen receptor (CAR) regulatory T cells (Tregs) to induce transplant tolerance. Her lab is working on the development of adoptive immunotherapy in nephrology and understanding Treg dysfunction.
Dr. Tandon is an Associate Professor of Medicine, Co-Director of the Cirrhosis Care Clinic, Transplant Hepatologist and lead of the Cirrhosis Care Alberta quality improvement program. She obtained her training at the University of Alberta, the Hospital Clinic in Barcelona and Yale University. Her clinical practice and research are focused on cirrhosis with research interests including cirrhosis related complications, malnutrition, frailty, exercise therapy, palliative care, integrative health approaches such as meditation and knowledge translation. It is her career goal to provide wholistic, interdisciplinary, evidence based, patient-centered care through education, empowerment, engagement and team-work.
Emily is a PhD student at the University of Alberta, where she completed her Master of Science (MSc) degree in medicine. With a passion for patient-oriented research and a commitment to improving health outcomes, Emily’s doctoral project focuses on EMPOWER, a 12-week online mind-body wellness program designed for adults living with chronic health conditions.
Dr Basil S. Nasir, M.B.B.Ch
Dr. Victor Ferreira is an Assistant Scientist in the Ajmera Transplant Centre at the University Health Network (UHN) and the Toronto General Hospital Research Institute (TGHRI). He is also an Assistant Professor at the University of Toronto in the Department of Laboratory Medicine and Pathobiology (LMP). He completed his PhD in Medical Sciences – Infection and Immunity Specialization at McMaster University in 2014 and post-doctoral training at UHN. His research program is focused on three pillars: I) using systems vaccinology to reveal insights into vaccine responses in immunocompromised individuals like transplant recipients; II) characterizing the impact of chronic viral infection on host immune responses; and III) developing novel methods for eliminating latent viruses in human organs. His work has been cited >2,500 times and is published in journals including the New England Journal of Medicine, Nature Immunology, the Lancet Infectious Diseases, Clinical Infectious Diseases, the American Journal of Transplantation and Journal of Infectious Diseases.