Gender-Specific Issues in Liver and Kidney Failure and Transplantation: A Review

Sex and gender disparity in kidney transplantation: Historical and future perspectives

Sex and gender disparity exist in various stages of kidney transplantation. Females were found to be less likely to be referred for kidney transplant, complete pre-transplant evaluation, be placed on the waitlist, and receive a kidney transplant compared to their male counterparts. Interestingly, females comprise the majority of living kidney donors. This review explores the biological and psychosocial factors that contribute to sex and gender disparity in kidney transplantation and proposes ways to address the disparity.

Diabetes and Cardiovascular Risk in Renal Transplant Patients

End-stage kidney disease (ESKD) is a main public health problem, the prevalence of which is continuously increasing worldwide. Due to adverse effects of renal replacement therapies, kidney transplantation seems to be the optimal form of therapy with significantly improved survival, quality of life and diminished overall costs compared with dialysis. However, post-transplant patients frequently suffer from post-transplant diabetes mellitus (PTDM) which an important risk factor for cardiovascular and cardiovascular-related deaths after transplantation. The management of post-transplant diabetes resembles that of diabetes in the general population as it is based on strict glycemic control as well as screening and treatment of common complications. Lifestyle interventions accompanied by the tailoring of immunosuppressive regimen may be of key importance to mitigate PTDM-associated complications in kidney transplant patients. More transplant-specific approach can include the exchange of tacrolimus with an alternative immunosuppressant (cyclosporine or mammalian target of rapamycin (mTOR) inhibitor), the decrease or cessation of corticosteroid therapy and caution in the prescribing of diuretics since they are independently connected with post-transplant diabetes. Early identification of high-risk patients for cardiovascular diseases enables timely introduction of appropriate therapeutic strategy and results in higher survival rates for patients with a transplanted kidney.

Feasibility and Perception of Cross-sex Face Transplantation to Expand the Donor Pool

Background:

A major challenge in face transplantation (FT) is the limited donor allograft pool. This study aimed to investigate the feasibility of cross-sex FT (CSFT) for donor pool expansion by: (1) comparing craniomaxillofacial metrics following CSFT versus same-sex FT (SSFT); and (2) evaluating the public and medical professionals’ perception of CSFT.

Methods:

Seven cadaveric FTs were performed, resulting in both CSFT and SSFT. Precision of bony and soft tissue inset was evaluated by comparing pre- versus post-operative cephalometric and anthropometric measurements. Fidelity of the FT compared to the virtual plan was assessed by imaging overlay techniques. Surveys were administered to medical professionals, medical students, and general population to evaluate opinions regarding CSFT.

Results:

Five CSFTs and 2 SSFTs were performed. Comparison of recipients versus post-transplant outcomes showed that only the bigonial and medial intercanthal distances were statistically different between CSFT and SSFT (P = 0.012 and P = 0.010, respectively). Of the 213 survey participants, more were willing to donate for and undergo SSFT, compared with CSFT (donate: 59.6% versus 53.0%, P = 0.001; receive: 79.5% versus 52.3%, P < 0.001). If supported by research, willingness to receive a CSFT significantly increased to 65.6% (P < 0.001). On non-blinded and blinded assessments, 62.9% and 79% of responses rated the CSFT superior or equal to SSFT, respectively.

Conclusions:

Our study demonstrates similar anthropometric and cephalometric outcomes for CSFT and SSFT. Participants were more reticent to undergo CSFT, with increased willingness if supported by research. CSFT may represent a viable option for expansion of the donor pool in future patients prepared to undergo transplantation.

The SURF (Italian observational study for renal insufficiency evaluation in liver transplant recipients): a post-hoc between-sex analysis

Background

Female sex has been reported as an independent predictor of severe post-liver transplantation (LT) chronic kidney disease. We performed a by sex post-hoc analysis of the SURF study, that investigated the prevalence of renal impairment following LT, aimed at exploring possible differences between sexes in the prevalence and course of post-LT renal damage.

Methods

All patients enrolled in the SURF study were considered evaluable for this sex-based analysis, whose primary objective was to evaluate by sex the proportion of patients with estimated Glomerular Filtration Rate (eGFR) < 60 ml/min/1.73m² at inclusion and follow-up visit.

Results

Seven hundred thirty-eight patients were included in our analysis, 76% males. The proportion of patients with eGFR < 60 mL/min/1.73 m² was significantly higher in females at initial study visit (33.3 vs 22.8%; p = 0.005), but also before, at time of transplantation (22.9 vs 14.7%; p = 0.0159), as analyzed retrospectively. At follow-up, such proportion increased more in males than in females (33.9 vs 26.0%, p = 0.04). Mean eGFR values decreased over the study in both sexes, with no significant differences. Statistically significant M/F differences in patient distribution by O’Riordan eGFR levels were observed at time of transplant and study initial visit (p = 0.0005 and 0.0299 respectively), but not at follow-up.

Conclusions

Though the limitation of being performed post-hoc, this analysis suggests potential sex differences in the prevalence of renal impairment before and after LT, encouraging further clinical research to explore such differences more in depth.

Factors associated with immune hemolytic anemia after pediatric liver transplantation

Immune-mediated hemolytic anemia following SOT is a rare disorder, the risk factors for which are unknown. Our purpose was to analyze a seemingly increased incidence in our center with the aim to identify predisposing factors. This recipients single-center retrospective study reviewed the medical records of 96 pediatric LT between 2000 and 2013. IHA was defined as acute anemia with a positive direct antiglobulin test. Seven cases of immune-mediated hemolytic anemia were identified (incidence 8.5%). Three cases presented during the first 3 months following LT (early IHA), and 4 presented later (late IHA). All patients with late IHA required rituximab. Using univariate analysis, the following factors were associated with IHA onset: BA (P = .04), younger age (P = .04), and the use of IGL-1 preservation solution (P = .05). Late IHA was associated with viral infections occurring beyond 3 months following LT, younger age, and BA (P = .01). Overall, CMV infection was associated with the development of both early and late IHA: CMV-negative recipients who received an organ from a CMV-positive donor were more likely to develop IHA (P = .035), and de novo CMV infection during the first year post-LT was associated with late IHA (P = .03). IHA is a rare complication following pediatric LT, occurring more frequently in younger patients and patients with an initial diagnosis of BA. CMV-negative recipients and patients who experience a de novo CMV infection in the first year following LT seem particularly vulnerable. IGL-1 preservation solution may be associated with an increased likelihood of developing IHA, a novel finding which warrants further investigation.

Analysis of Morbidity in Liver Transplant Recipients following Human Albumin Supplementation: A Retrospective Pilot Study

Objectives

To assess incidence of morbidity (ie, documented infection, acute renal failure, acute graft rejection, acute cardiovascular events, and hospital read-mission rates) 6 months following liver transplantation using linear regression as a function of cumulative albumin dose.

Design

Retrospective chart review.

Setting

A 473-bed tertiary care teaching facility with a solid-organ transplantation center.

Patients

Forty liver transplant recipients examined from January 1 to December 31, 2003.

Measurements and Results

Data from 40 liver transplant recipients were collected. Mean albumin dose administered was 190.9 ± 162.3 g. No statistical differences were identified in patients receiving less than 140 g (n = 20) or more than 140 g (n = 20) with respect to demographic data other than gender and ethnicity. The mean APACHE III (Acute Physiology and Chronic Health) score was 69.7 ± 24.3. Approximately 70 episodes of morbidity and 23 readmissions were observed. Regardless of the APACHE III score, albumin was associated with increased overall morbidity and cardiovascular complications. Liver transplant recipients receiving more than 140 g had a longer hospital stay (14 vs 8 days, P = .025) and intensive care unit stay (6 vs 3 days, P = .051) than patients receiving 140 g or less. No correlation with risk of acute rejection was seen with albumin or tacrolimus.

Conclusion

Albumin supplementation among liver transplant recipients was associated with a significant risk for cardiovascular complications and overall number of complications regardless of APACHE III score. Future prospective studies are needed to further define the potential risk for complications in this patient population.

Gender in the allocation of organs in kidney transplants: meta-analysis

OBJECTIVE

To analyze whether gender influence survival results of kidney transplant grafts and patients.

METHODS

Systematic review with meta-analysis of cohort studies available on Medline (PubMed), LILACS, CENTRAL, and Embase databases, including manual searching and in the grey literature. The selection of studies and the collection of data were conducted twice by independent reviewers, and disagreements were settled by a third reviewer. Graft and patient survival rates were evaluated as effectiveness measurements. Meta-analysis was conducted with the Review Manager^® 5.2 software, through the application of a random effects model. Recipient, donor, and donor-recipient gender comparisons were evaluated.

RESULTS

: Twenty-nine studies involving 765,753 patients were included. Regarding graft survival, those from male donors were observed to have longer survival rates as compared to the ones from female donors, only regarding a 10-year follow-up period. Comparison between recipient genders was not found to have significant differences on any evaluated follow-up periods. In the evaluation between donor-recipient genders, male donor-male recipient transplants were favored in a statistically significant way. No statistically significant differences were observed in regards to patient survival for gender comparisons in all follow-up periods evaluated.

CONCLUSIONS

The quantitative analysis of the studies suggests that donor or recipient genders, when evaluated isolatedly, do not influence patient or graft survival rates. However, the combination between donor-recipient genders may be a determining factor for graft survival.

Gender differences in renal transplant graft survival

BACKGROUND/PURPOSE

A long-term retrospective study was conducted to assess the risk factors of renal transplant graft failure focusing on the effects of gender of both the donor and the recipient.

METHODS

Medical records of primary renal transplantation performed in a single transplant hospital were reviewed. Cases of ABO incompatibility, positive cross-matches, or multiple organ transplants were excluded. A total of 766 patient records were reviewed, and variables were analyzed with Kaplan-Meier survival curves and Cox regression to determine the independent factors associated with graft survival.

RESULTS

The overall 5-year graft and patient survival rates were 84.7% and 92.2%, respectively. Univariate analysis showed significantly poorer prognosis in male patients and in those with acute rejection, delayed function, or more mismatches in human lymphocyte antigens. Multivariate analysis with step-wise regression identified three independent prognostic factors for poor graft survival (male gender, acute rejection, and delayed function). The 5-year graft survival rates for female and male patients were 87.9% and 81.3%, respectively. The risk ratio of graft failure for male renal transplant recipients was 1.3732, when compared with that for female patients. The risk ratios for those with acute rejection and delayed function were 1.8330 and 1.5422, respectively.

CONCLUSION

Male gender, in addition to acute rejection and delayed function, was found to be an independent prognostic factor for poor renal transplant survival in this long-term retrospective study.

Deceased donor risk factors influencing liver transplant outcome

As the pressure for providing liver transplantation to more and more candidates increases, transplant programs have begun to consider deceased donor characteristics that were previously considered unacceptable. With this trend, attention has focused on better defining those donor factors that can impact the outcome of liver transplantation. This review examines deceased donor factors that have been associated with patient or graft survival as well as delayed graft function and other liver transplant results.

Risk factors that increase mortality after living donor liver transplantation

BACKGROUND

Female liver to male recipient is a well-accepted risk factor for graft loss in cadaveric liver transplantation. However, gender matching is infeasible because of an insufficient number of available donors. No studies have been performed on the role of gender in the field of living donor liver transplantation. This report investigates the effect of gender mismatch on the outcome of living donor liver transplantation.

METHODS

A total of 335 patients and donors were classified into four groups according to the following gender combinations: male donor to male recipient group (n=104), male donor to female recipient group (n=120), female donor to male recipient (FM) group (n=59), and female donor to female recipient group (n=52). Patient and graft survival were compared among the groups. We performed a multivariable analysis to identify the factors associated with patient mortality.

RESULTS

The 1-, 3-, 5-, and 10-year patient survival rates in the FM group were 80.6%, 66.8%, 61.8%, and 47.7%, respectively. The FM group showed significantly shorter patient survival compared with the other three groups. Independent risk factors for patient mortality were: FM group (P=0.006), pretransplant diabetes mellitus (P=0.001), and a model for end-stage liver disease score more than or equal to 20 (P=0.004).

CONCLUSIONS

Male recipients of transplants from female donors, pretransplant diabetes mellitus, and a model for end-stage liver disease score more than or equal to 20 have poor survival rates.

Detecting Blood Laboratory Errors Using a Bayesian Network

Objectives: To detect errors in blood laboratory results using a Bayesian network (BN), to compare results with an established method for detecting errors based on frequency patterns (LabRespond) and logistic regression model. Methods: In Experiment 1 and 2 using a sample of 5,800 observations from the National Health and Nutrition Examination Survey dataset, large, medium and small errors were randomly generated and introduced to liver enzymes (ALT, AST, and LDH) of the dataset. Experiment 1 examined systematic errors, while Experiment 2 investigated random errors. The outcome of interest was the correct detection of liver enzymes as “error” or “not error.” With the BN, the outcome was predicted by exploiting probabilistic relationships among AST, ALT, LDH, and gender. In addition to AST, ALT, LDH, and gender, LabRespond required more information on related analytes to achieve optimal prediction. We assessed performance by examining the area under the receiver operating characteristics curves using a 10-fold cross validation method, as well as risk stratification tables. Results: In Experiment 1, the BN significantly outperformed both LabRespond and logistic regression in detecting large (both at p < 0.001), medium ( p = 0.01 and p < 0.001, respectively), and small ( p = 0.03 and, p = 0.05, respectively) systematic errors. In Experiment 2, the BN performed significantly better than LabRespond and multinomial logistic regression in detecting large ( p = 0.04 and p < 0.001, respectively) and medium ( p = 0.05 and p < 0.001, respectively) random errors. Conclusion: A Bayesian network is better at detection and can detect errors with less information than existing automated models, suggesting that Bayesian model may be an effective means for reducing medical costs and improving patient safety.

Gender-incompatible liver transplantation is not a risk factor for patient survival

BACKGROUND/AIMS

Clinical data may be suggestive for differences in patient survival in gender-incompatible orthotopic liver transplantation (OLT), but findings are inconsistent and are putatively linked to circulating hormones. We therefore investigated patient survival as well as metabolism of steroids to identify possible causes of improved graft survival in gender-mismatched OLT.

METHODS

We examined our single-centre database of 1355 recipients of first liver transplants for overall patient survival by non-parametric and parametric analysis of multivariance taking the age of recipient and donor, ischaemia time, underlying liver disease and the time period of transplantation into account. Furthermore, the metabolism of androgens in gender-incompatible OLT was studied in cultures of primary human hepatocytes obtained from male and female patients.

RESULTS

Unlike previous studies we were unable to determine overall significant differences in patient survival in gender-incompatible OLT, even though a statistically significant improved patient survival was observed when male donor livers were transplanted into female recipients in univariant analysis (P=0.047). However, when the overall patient management was taken into account no difference in survival was determined in multivariant analysis. Importantly, the metabolism of testosterone did not differ between male and female hepatocyte cultures, except for the production of 6-alpha-hydroxy-testosterone (P<0.001).

CONCLUSIONS

Taken collectively, clinical observations may tend to suggest a slightly improved patient survival in gender-incompatible OLT but this cannot be explained on the bases of androgen metabolism. Overall, we view gender-incompatible liver transplantation not to be a confounder in patient survival after OLT.

Gender differences in survival after lung transplant: implications for cancer etiology

Predictors of survival after lung transplant were analyzed in a large cohort of 990 lung transplanted patients from a single center. The overall survival was 41.6%, (41.5% in males, and 41.8% in females), the average length of the follow up was 45.84+/-51.98 months (range 0-282.47 months). Females tend to live longer than males: 50.75+/-55.41 months versus 40.64+/-47.60 months, respectively. Males had a risk of dying during the follow up that was 1.18 (95% CI 1.01-1.40) relative to females, after adjusting for ethnicity, age, smoking status, diagnosis and donor characteristics. Females who had at least one full term pregnancy during their life had better survival rates than females who had no full term pregnancies. Our results of a better survival after lung transplant in females, and among them in those who had at least a full term pregnancy support the hypothesis of a hormonal contribution to survival and of the development of immunotolerance after pregnancy. This model could be useful for understanding the role of immunity in cancer development.

Risk assessment in haematopoietic stem cell transplantation: Impact of donor–recipient sex combination in allogeneic transplantation

In allogeneic transplantation the donor-recipient sex combination plays a role in outcome. In large retrospective registry studies of several thousands of patients with aplastic anemia, chronic myelocytic leukemia (CML), acute myelocytic leukemia (AML), and multiple myeloma, chronic graft-versus-host disease (cGVHD) was more frequent and transplant-related mortality (TRM) higher in males with a female donor (F-->M) than in other donor-recipient sex combinations. Graft rejection was more frequent in females with a male donor (M-->F) in aplastic anemia, and a graft-versus-tumor effect (GVT) was documented as a reduced relapse rate in F-->M in CML, AML and multiple myeloma. The overall survival was adversely affected in F-->M in aplastic anemia, AML and CML and in M-->F in aplastic anemia. These results support the view that donor T cells specific for male minor histocompatiblity antigens encoded by Y-chromosome genes contribute to GVHD, graft rejection, GVT and survival in sex-mismatched transplants.