Does the UNOS heart transplant allocation system favor men over women?

"My feelings and my thoughts are my lived experience, not the numbers they show me on a piece of paper": Indigenous experiences of liver transplantation in British Columbia, Canada

Indigenous Peoples in Canada face healthcare inequities impacting access to solid organ transplantation. The experiences of Indigenous patients during the liver transplant process, and how transplant professionals perceive challenges faced by Indigenous Peoples, has not been studied. Thirteen semi-structured qualitative interviews were conducted via telehealth with Indigenous liver transplant patients (n = 7) and transplant care providers (n = 6) across British Columbia, Canada between April 2021-May 2022. Themes were identified to inform clinical approaches and transplant care planning and validated by Indigenous health experts. Among patient participants: transplants occurred between 1992-2020; all were women; and the mean age at the time of interview was 60 years. Among transplant care provider participants: roles included nursing, social work, and surgery; 83% were women; and the median number of years in transplant care was ten. Three broad themes were identified: Indigenous strengths and resources, systemic and structural barriers, and inconsistent care and cultural safety across health professions impact Indigenous patient care during liver transplantation. This study contributes insights into systemic barriers and Indigenous resilience in the liver transplant journey. Dismantling structural barriers to early linkage to care is needed, and training for transplant clinicians on Indigenous histories, cultural protocols, and cultural safety is strongly recommended.

Sex and Gender-related Disparities in Clinical Characteristics and Outcomes in Heart Transplantation

PURPOSE OF REVIEW

Limited research has been conducted on sex disparities in heart transplant (HT). The aim of this review is to analyse the available evidence on the influence of sex and gender-related determinants in the entire HT process, as well as to identify areas for further investigation.

RECENT FINDINGS

Although women make up half of the population affected by heart failure and related mortality, they account for less than a third of HT recipients. Reasons for this inequality include differences in disease course, psychosocial factors, concerns about allosensitisation, and selection or referral bias in female patients. Women are more often listed for HT due to non-ischaemic cardiomyopathy and have a lower burden of cardiovascular risk factors. Although long-term prognosis appears to be similar for both sexes, there are significant disparities in post-HT morbidity and causes of mortality (noting a higher incidence of rejection in women and of malignancy and cardiac allograft vasculopathy in men). Additional research is required to gain a better understanding of the reasons behind gender disparities in eligibility and outcomes following HT. This would enable the fair allocation of resources and enhance patient care.

Sex-specific patterns of donor-derived cell-free DNA in heart transplant rejection: An analysis from the Genomic Research Alliance for Transplantation (GRAfT)

BACKGROUND

Noninvasive methods for surveillance of acute rejection are increasingly used in heart transplantation (HT), including donor-derived cell-free DNA (dd-cfDNA). As other cardiac biomarkers differ by sex, we hypothesized that there may be sex-specific differences in the performance of dd-cfDNA for the detection of acute rejection. The purpose of the current study was to examine patterns of dd-cfDNA seen in quiescence and acute rejection in male and female transplant recipients.

METHODS

Patients enrolled in the Genomic Research Alliance for Transplantation who were ≥18 years at the time of HT were included. Rejection was defined by endomyocardial biopsy with acute cellular rejection (ACR) grade ≥2R and/or antibody-mediated rejection ≥ pAMR 1. dd-cfDNA was quantitated using shotgun sequencing. Median dd-cfDNA levels were compared between sexes during quiescence and rejection. The performance of dd-cfDNA by sex was assessed using area under the receiver operator characteristic (AUROC) curve. Allograft injury was defined as dd-cfDNA ≥0.25%.

RESULTS

One hundred fifty-one unique patients (49 female, 32%) were included in the analysis with 1,119 available dd-cfDNA measurements. Baseline characteristics including demographics and comorbidities were not significantly different between sexes. During quiescence, there were no significant sex differences in median dd-cfDNA level (0.04% [IQR 0.00, 0.16] in females vs 0.03% [IQR 0.00, 0.12] in males, p = 0.22). There were no significant sex differences in median dd-cfDNA for ACR (0.33% [0.21, 0.36] in females vs 0.32% [0.21, 1.10] in males, p = 0.57). Overall, median dd-cfDNA levels were higher in antibody-mediated rejection (AMR) than ACR but did not significantly differ by sex (0.50% [IQR 0.18, 0.82] in females vs 0.63% [IQR 0.32, 1.95] in males, p = 0.51). Elevated dd-cfDNA detected ACR/AMR with an AUROC of 0.83 in females and 0.89 in males, p-value for comparison = 0.16.

CONCLUSIONS

There were no significant sex differences in dd-cfDNA levels during quiescence and rejection. Performance characteristics were similar, suggesting similar diagnostic thresholds can be used in men and women for rejection surveillance.

Differences in excess mortality by recipient sex after heart transplant: An individual patient data meta-analysis

BACKGROUND

Identification of differences in mortality risk between female and male heart transplant recipients may prompt sex-specific management strategies. Because worldwide, males of all ages have higher absolute mortality rates than females, we aimed to compare the excess risk of mortality (risk above the general population) in female vs male heart transplant recipients.

METHODS

We used relative survival models conducted separately in SRTR and CTS cohorts from 1988-2019, and subsequently combined using 2-stage individual patient data meta-analysis, to compare the excess risk of mortality in female vs male first heart transplant recipients, accounting for the modifying effects of donor sex and recipient current age.

RESULTS

We analyzed 108,918 patients. When the donor was male, female recipients 0-12 years (Relative excess risk (RER) 1.13, 95% CI 1.00-1.26), 13-44 years (RER 1.17, 95% CI 1.10-1.25), and ≥45 years (RER 1.14, 95% CI 1.02-1.27) showed higher excess mortality risks than male recipients of the same age. When the donor was female, only female recipients 13-44 years showed higher excess risks of mortality than males (RER 1.09, 95% CI 1.00-1.20), though not significantly (p = 0.05).

CONCLUSIONS

In the setting of a male donor, female recipients of all ages had significantly higher excess mortality than males. When the donor was female, female recipients of reproductive age had higher excess risks of mortality than male recipients of the same age, though this was not statistically significant. Further investigation is required to determine the reasons underlying these differences.

Outcomes of left-sided heart valve surgery after heart transplantation: a systematic review

As the survival after heart transplantation (HTx) is steadily improving, an increasing number of patients with late cardiac pathologies such as valvular disease is expected to rise. Nevertheless, no guidelines for indication of redo cardiac surgery after HTx exists. The aim of the present systematic review is to describe the results reported in the literature of surgical management of severe aortic and/or mitral valve disease. A systematic review was conducted including studies reporting on adult patients with severe mitral or aortic valve pathology needing surgery after their previous HTx. Exclusion criteria consisted in surgery with no left heart valve surgery, concomitant valve surgery during heart transplant, transcatheter interventions, and heterotopic HTx. A total of 35 papers met our inclusion criteria out of 2755 potentially eligible studies with 44 mitral valve surgery patients and 20 aortic valve surgery patients. In the entire population, the mean time from HTx to reintervention was 6.19 ± 5.22 years. After a mean follow-up of 2.78 ± 3.54 years and 1.53 ± 2.26 years from reintervention, 65.6% mitral and 86.7% aortic patients were reported as alive, respectively. As guidelines on cardiac surgery after HTx are currently lacking, left-sided valvular cardiac reinterventions can be considered a possible therapeutic approach in carefully selected patients. These interventions may not only improve the patient's functional status and survival, but may ultimately reduce the need for re-transplantation due to the chronic shortage of donor hearts. However, the support of more robust data is warranted.

Sex Differences in Cardiac Transplantation

PURPOSE OF REVIEW

The goal of this review was to summarize contemporary evidence surrounding sex differences in heart transplantation (HT).

RECENT FINDINGS

Women have steadily comprised approximately 25% of waitlist candidates and HT recipients. This disparity is likely multifactorial with possible explanations including barriers in referral to advanced heart failure providers, implicit bias, and concerns surrounding sensitization. Women continue to experience higher waitlist mortality at the highest priority tiers. After HT, there are differences in post-transplant complications and outcomes. Future areas of study should include sex differences in noninvasive surveillance, renal outcomes after transplantation, and patient-reported outcomes. There are important sex-specific considerations that impact candidate selection, donor matching, waitlist and post-transplant outcomes. Concerted efforts are needed to improve referral patterns to ensure transplantation is allocated equally.

Increased Opportunities for Transplantation for Women in the New Heart Allocation System

BACKGROUND

Historically, women have had less access to advanced heart failure therapies, including temporary and permanent mechanical circulatory support and heart transplantation (HT), with worse waitlist and post-transplant survival compared with men. This study evaluated for improvement in sex differences across all phases of HT in the 2018 allocation system.

METHODS AND RESULTS

The United Network for Organ Sharing registry was queried to identify adult patients (≥18 years) listed for HT from October 18, 2016, to October 17, 2018 (old allocation), and from October 18, 2018, to October 18, 2020 (new allocation). The outcomes of interest included waitlist survival, pretransplant use of temporary and durable mechanical circulatory support, rates of HT, and post-transplant survival. There were 15,629 patients who were listed for HT and included in this analysis; 7745 (2039 women, 26.3%) in the new and 7875 patients (2074 women, 26.3%) in the old allocation system. When compared with men in the new allocation system, women were more likely to have lower priority United Network for Organ Sharing status at time of transplant, and less likely to be supported by an intra-aortic balloon pump (27.1% vs 32.2%, P < .001), with no difference in the use of venoarterial extracorporeal membrane oxygenation (5.5% vs 6.3%, P = .28). Despite these findings, when transplantation was viewed in the context of risk for death or delisting, the cumulative incidence of transplant within 6 months of listing was higher in women than men in the new allocation system (62.4% vs 54.9%, P < .001) with no differences in post-transplant survival. When comparing women in the old with the new allocation system, the distance traveled for organ procurement was 187.5 ± 207.0 miles vs 272.8 ± 233.7 miles (P < .001).

CONCLUSIONS

Although the use of temporary mechanical circulatory support in women remains lower than in men in the new allocation system, more women are being transplanted with comparable waitlist and post-transplant outcomes as men. Broader sharing may be making its greatest impact on improving transplant opportunities for women.

The Canadian Women's Heart Health Alliance Atlas on the Epidemiology, Diagnosis, and Management of Cardiovascular Disease in Women - Chapter 5: Sex- and Gender-Unique Manifestations of Cardiovascular Disease

This Atlas chapter summarizes sex- and some gender-associated, and unique aspects and manifestations of cardiovascular disease (CVD) in women. CVD is the primary cause of premature death in women in Canada and numerous sex-specific differences related to symptoms and pathophysiology exist. A review of the literature was done to identify sex-specific differences in symptoms, pathophysiology, and unique manifestations of CVD in women. Although women with ischemic heart disease might present with chest pain, the description of symptoms, delay between symptom onset and seeking medical attention, and prodromal symptoms are often different in women, compared with men. Nonatherosclerotic causes of angina and myocardial infarction, such as spontaneous coronary artery dissection are predominantly identified in women. Obstructive and nonobstructive coronary artery disease, aortic aneurysmal disease, and peripheral artery disease have worse outcomes in women compared with men. Sex differences exist in valvular heart disease and cardiomyopathies. Heart failure with preserved ejection fraction is more often diagnosed in women, who experience better survival after a heart failure diagnosis. Stroke might occur across the lifespan in women, who are at higher risk of stroke-related disability and age-specific mortality. Sex- and gender-unique differences exist in symptoms and pathophysiology of CVD in women. These differences must be considered when evaluating CVD manifestations, because they affect management and prognosis of cardiovascular conditions in women.

Sex disparities in the current era of pediatric heart transplantation in the United States

BACKGROUND

While sex-related differences in transplant outcomes have been well characterized amongst adults, there are no sex-specific pediatric heart transplant studies over the last decade and none evaluating waitlist outcomes. In a contemporary cohort of children undergoing heart transplantation in the United States, this analysis was performed to determine if there were sex disparities in waitlist and/or post-transplant outcomes.

METHODS

Retrospective review of Scientific Registry of Transplant Recipients database from December 16, 2011 to February 28, 2019 to compare male and female children after listing and after transplant. Demographic, clinical characteristics and outcomes were compared unadjusted and after 1:1 propensity matching for selected covariates.

RESULTS

Of 4089 patients, 2299 (56%) were males. At listing, males were more likely to be older, have congenital heart disease (58% vs 48%), renal dysfunction (49% vs 44%) and implantable cardioverter defibrillator (9% vs 7%). At transplant, males were more likely to have renal (42 % vs 35%) and liver dysfunction (13% vs 10%), PRA >10% (29% vs 22%) and ischemic time >3.5 hours (p < 0.05 for all). There were no significant sex differences found in unadjusted rates of transplant or mortality. After propensity matching, females had increased waitlist mortality (HR 1.3, 95%CI 1.04-1.5; p =0.019) compared to males. There were no significant differences in post-transplant morbidity or mortality (HR 1.2, 95% CI 0.93-1.5; p = 0.18) between groups.

CONCLUSION

In a contemporary pediatric cohort, females have inferior heart transplant waitlist survival compared to propensity-matched males despite lower acuity of illness at listing and similar rates of transplantation. There were no sex-disparities noted in post-transplant outcomes.

Sex Disparity in Transplant: A Problem Hiding in Plain Sight

This month’s installment of “The AJT Report” explores the challenge of sex disparity in transplant and what might be done to address this ongoing problem. We also report on a recent amendment to the U.S. Food and Drug Administration’s COVID-19 vaccine emergency use authorizations that affects solid organ recipients.

Influence of Gender in Advanced Heart Failure Therapies and Outcome Following Transplantation

Biological differences between males and females change the course of different diseases and affect therapeutic measures' responses. Heart failure is not an exception to these differences. Women account for a minority of patients on the waiting list for heart transplantation or other advanced heart failure therapies. The reason for this under-representation is unknown. Men have a worse cardiovascular risk profile and suffer more often from ischemic heart disease. Conversely, transplanted women are younger and more frequently have non-ischemic cardiac disorders. Women's poorer survival on the waiting list for heart transplantation has been previously described, but this trend has been corrected in recent years. The use of ventricular assist devices in women is progressively increasing, with comparable results than in men. The indication rate for a heart transplant in women (number of women on the waiting list for millions of habitants) has remained unchanged over the past 25 years. Long-term results of heart transplants are equal for both men and women. We have analyzed the data of a national registry of heart transplant patients to look for possible future directions for a more in-depth study of sex differences in this area. We have analyzed 1-year outcomes of heart transplant recipients. We found similar results in men and women and no sex-related interactions with any of the factors related to survival or differences in death causes between men and women. We should keep trying to approach sex differences in prospective studies to confirm if they deserve a different approach, which is not supported by current evidence.

Gender differences in heart transplantation: Twenty-five year trends in the nationwide Spanish heart transplant registry

The study of gender differences may lead into improvement in patient care. We have aimed to identify the gender differences in heart transplantation (HT) of adult HT recipients in Spain and their evolution in a study covering the years 1993-2017 in which 6740 HT (20.6% in women) were performed. HT indication rate per million inhabitants was lower in women, remaining basically unchanged during the 25-year study period. HT rate was higher in men, although this decreased over the 25-year study period. Type of heart disease differed in men versus women (p < .001): ischemic heart disease 47.6% versus 22.5%, dilated cardiomyopathy 41.3% versus 34.6%, or other 36% versus 17.8%, respectively. Men were more frequently diabetics (18% vs. 13.1% p < .001), hypertensives (33.1% vs. 24% p < .001), and smokers (21.7% vs. 12.9% p < .001), respectively. Women had more pre-HT malignancies (7.1% vs. 2.8% p < .001), and their clinical status was worse at HT due to renal function and mechanical ventilation. Adjusted survival (p = .198) and most of the mortality-related variables were similar in men and women. Death occurred more frequently in women due to rejection (7.9% vs. 5.1% p < .001) and primary failure (18.2% vs. 12.5% p < .001) and in men due to malignancies (15.1% vs. 6.6% p < .001).

Clinical presentation and outcomes in women and men with advanced heart failure

OBJECTIVE

To examine clinical characteristics and outcomes in women and men referred for advanced heart failure (HF) therapies such as left ventricular assist device (LVAD) or heart transplantation (HTx). Design: A retrospective study of 429 (23% women) consecutive adult HF patients not on inotropic or mechanical circulatory support with left ventricular ejection fraction ≤45% referred for assessment of advanced HF therapies at a single tertiary institution between 2002 and 2016. Clinical characteristics and outcomes were compared in women and men, and all patients underwent right heart catheterization (RHC). Results: At evaluation, women were younger than men (48 ± 13 vs. 51 ± 12 years, p = .02), and less likely to have ischemic cardiomyopathy. There were no significant differences in NYHA class, contemporary HF therapy use, or physical examination findings, except for lower jugular vein distension and body surface area in women. On RHC, women had lower cardiac filling pressures, but similar pulmonary vascular resistance and cardiac index. Peak oxygen uptake from cardiopulmonary exercise testing was similar in both sexes. At total follow-up time, there were 164 deaths (21% vs. 44%, p < .0001), 46 LVADs (3% vs. 13%, p = .005), 110 HTxs (32% vs. 25%, p = .15), and 82 HTxs without requiring LVAD (29% vs. 16%, p = .03) in women and men. The time from RHC to HTx (±LVAD) was significantly shorter in women compared to men. Female sex was significantly associated with higher survival independent of time-trend, age, and comorbidities. Conclusion: At evaluation, hemodynamics were less deranged in women. A higher proportion of women received HTx, their waitlist time was shorter, and survival greater.

Heart Transplantation: An In-Depth Survival Analysis

OBJECTIVES

This study aims to understand the complex factors affecting heart transplant survival and to determine the importance of possible sex-specific risk factors.

BACKGROUND

Heart transplant allocation is primarily focused on preventing waitlist mortality. To prevent organ wastage, future allocation must balance risk of waitlist mortality with post-transplantation mortality. However, more information regarding risk factors after heart transplantation is needed.

METHODS

We included all adults (30,606) in the Scientific Registry of Transplant Recipients database who underwent isolated heart transplantation from January 1, 2004, to July 1, 2018. Mortality (8,278 deaths) was verified with the complete Social Security Death Index with a median follow-up of 3.9 years. Temporal decomposition was used to identify phases of survival and phase-specific risk factors. The random survival forests method was used to determine importance of mortality risk factors and their interactions.

RESULTS

We identified 3 phases of mortality risk: early post-transplantation, constant, and late. Sex was not a significant risk factor. There were several interactions predicting early mortality such as pretransplantation mechanical ventilation with presence of end-organ function (bilirubin, renal function) and interactions predicting later mortality such as diabetes and older age (donor and recipient). More complex interactions predicting early-, mid-, and late-mortality existed and were identified with machine learning (i.e., elevated bilirubin, mechanical ventilation, and dialysis).

CONCLUSIONS

Post-heart transplant mortality risk is complex and dynamic, changing with time and events. Sex is not an important mortality risk factor. To prevent organ wastage, end-organ dysfunction should be resolved before transplantation as much as possible.

Ambulatory Advanced Heart Failure in Women: A Report From the REVIVAL Registry

OBJECTIVES

This study sought to explore clinical characteristics and outcomes in women and men with ambulatory advanced heart failure (HF).

BACKGROUND

Women have been underrepresented in studies of advanced HF and have an increased mortality on the transplant waiting list and early after mechanical circulatory support (MCS). An increased understanding of the differential burden of HF between women and men is required to inform the use of mechanical circulatory support in ambulatory advanced HF patients.

METHODS

REVIVAL (Registry Evaluation for Vital Information on Ventricular Assist Devices in Ambulatory Life) is a prospective, observational study of 400 outpatients with chronic systolic HF, New York Heart Association functional class II to IV, and 1 additional high-risk feature. Clinical characteristics, quality of life, and functional capacity were compared between women and men, as was a primary composite endpoint of death, durable MCS, or urgent heart transplantation at 1 year.

RESULTS

REVIVAL enrolled 99 women (25% of the cohort) who had similar age, ejection fraction, INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profiles, medication use, and willingness to consider MCS as the men enrolled; however, women reported significantly greater limitations in quality of life with respect to physical limitation, reduced 6-min walk distance, and more frequent symptoms of depression. Nevertheless, 1-year combined risk of death, durable MCS, or urgent transplantation did not differ between women and men (24% vs. 22%; p = 0.94).

CONCLUSIONS

This study represents the largest report to date of women with ambulatory advanced HF receiving contemporary therapies. Systematic elicitation of patient-reported outcome measures uncovered an added burden of HF in women and may be an appropriate target of augmented support and intervention.

Sex differences in preformed panel-reactive antibody levels and outcomes in patients undergoing heart transplantation

BACKGROUND

Sex differences in panel-reactive antibody (PRA) levels in heart transplant recipients and their association with transplant-related outcomes are mostly unknown.

METHODS

In 20 181 (24.7% women) first-time heart transplant recipients included from July 2004 to March 2015 in the prospective Organ Procurement and Transplantation Network (OPTN), we studied sex differences in most recent (mr) and peak (p)PRA and outcomes (graft failure, rejection, cardiac allograft vasculopathy [CAV], retransplantation, and mortality). Median follow-up (all-cause mortality) was 6 years. Analyses are based on OPTN data (March 6, 2017).

RESULTS

MrPRA levels were associated with all-cause mortality (hazard ratio, 95% confidence interval: class I 1.03, 1.01-1.04, P < 0.001) and acute rejection (class II 1.08, 1.03-1.14, P = 0.0044). PPRA levels were associated with all-cause mortality (class I 1.02, 1.00-1.04, P = 0.015) and CAV (class II 1.03, 1.01-1.06, P = 0.020). Sex interactions were seen for the association of pPRA and graft failure with a higher risk in women, and for pPRA and CAV with a higher risk in men.

CONCLUSIONS

PRA were associated with different transplant-related outcomes in both sexes. However, women with elevated pPRA were shown to be at higher risk for graft failure, whereas higher levels of pPRA were more hazardous for men in developing CAV.

Sex Differences in the Management of Advanced Heart Failure

PURPOSE OF REVIEW

Heart failure (HF) is prevalent among women and remains a leading cause of morbidity and mortality in the United States. Currently, 3 million women live with HF and the prevalence is projected to continue to increase. The purpose of this review is to highlight sex differences in the use and response to evidence-based pharmacological, device, and advanced HF therapies, as well as explore emerging areas of research in sex differences in the treatment of HF.

RECENT FINDINGS

Under-representation of women in clinical HF trials has limited our understanding of sex-related differences in the treatment and outcomes of HF. Important sex differences exist in the use of evidence-based HF therapies and clinical response among women with HF. In general, women tend to obtain the same clinical benefit from evidence-based HF drug and device therapies, but the utilization rates of guideline-directed medical therapies remain poor compared to men. Future research efforts should focus on increasing the enrollment of women in HF trials to help gain helpful insight into sex-specific differences in treatment effects and subsequent clinical outcomes.

Advances in Cardiovascular Health in Women over the Past Decade: Guideline Recommendations for Practice

Cardiovascular disease (CVD) remains the number one cause of death in women. It is estimated that 44 million women in the United States are either living with or at risk for heart disease. This article highlights the recent significant progress made in improving care, clinical decision-making, and policy implications for women with CVD. We provide our perspective supported by evidence-based advances in cardiovascular research and clinical care guidelines in seven areas: (1) primary CVD prevention and community heart care, (2) secondary prevention of CVD, (3) stroke, (4) heart failure and cardiomyopathies, (5) ischemia with nonobstructive coronary artery disease, (6) spontaneous coronary artery dissection, and (7) arrhythmias and device therapies. Advances in these fields have improved the lives of women living with and at risk for heart disease. With increase awareness, partnership with national organizations, sex-specific research, and changes in policy, the morbidity and mortality of CVD in women can be further reduced.

Sex Differences in Mortality Based on United Network for Organ Sharing Status While Awaiting Heart Transplantation

BACKGROUND

There are sex differences in mortality while awaiting heart transplantation, and the reason remains unclear.

METHODS AND RESULTS

We included all adults in the Scientific Registry of Transplant Recipients placed on the heart transplant active waitlist from 2004 to 2015. The primary end point was all-cause mortality. Multivariable Cox proportional hazards models were performed to evaluate survival by United Network for Organ Sharing (UNOS) status at the time of listing. Random survival forest was used to identify sex interactions for the competing risk of death and transplantation. There were 33 069 patients (25% women) awaiting heart transplantation. This cohort included 7681 UNOS status 1A (26% women), 13 027 UNOS status 1B (25% women), and 12 361 UNOS status 2 (26% women). During a median follow-up of 4.3 months, 1351 women and 4052 men died. After adjusting for >20 risk factors, female sex was associated with a significant risk of death among UNOS status 1A (adjusted hazard ratio, 1.14; 95% confidence interval, 1.01-1.29) and UNOS status 1B (adjusted hazard ratio, 1.17; 95% confidence interval, 1.05-1.30). In contrast, female sex was significantly protective for time to death among UNOS status 2 (adjusted hazard ratio, 0.85; 95% confidence interval, 0.76-0.95). Sex differences in probability of transplantation were present for every UNOS status, and >20 sex interactions were identified for mortality and transplantation.

CONCLUSIONS

When stratified by initial UNOS status, women had a higher mortality than men as UNOS status 1 and a lower mortality as UNOS status 2. With >20 sex interactions for mortality and transplantation, further evaluation is warranted to form a more equitable allocation system.

Matching the Market for Heart Transplantation

Heart transplantation is the most effective therapy for patients with Stage D heart failure with a median life expectancy of ≈10 to 15 years. Unfortunately, many patients die on the waiting list hoping for a chance of survival. The life boat cannot rescue everyone. Over a decade, the donor pool has remained relatively stable, whereas the number of heart transplant candidates has risen. Potential recipients often have many comorbidities and are older because the criteria for heart transplantation has few absolute contraindications. Women, Hispanics, and patients with restrictive heart disease and congenital heart disease are more likely to die while awaiting heart transplantation than men, white patients, and those with either ischemic or dilated cardiomyopathy. To better match the market, we need to (1) increase the donor pool, (2) reduce the waitlist, and (3) improve the allocation system. This review article addresses all 3 options and compares strategies in the United States to those in other countries.

Clinical and gender differences in heart transplant recipients in the NEW HEART study

BACKGROUND

Little attention has focused on gender differences in cardiac comorbidities and outcomes in patients undergoing orthotropic heart transplant.

OBJECTIVE

The objective of this study was to investigate gender differences at baseline and during follow-up among heart transplant patients.

METHODS

An observational cohort within the NEW HEART study was evaluated to determine gender differences in relation to age, coexisting cardiac comorbidities, and outcomes. Differences were assessed by t-test, Fisher's exact test, and logistic regression analysis.

RESULTS

Male transplant recipients ( n = 238) were significantly older than female recipients ( n = 92), with a greater percentage over 60 years of age (45% vs. 24%, p = 0.0006). Males were more likely to have hypertension (63% vs. 49%, p = 0.034), dyslipidemia (62% vs. 45%, p = 0.006), a history of smoking (52% vs. 35%, p = 0.009), and diabetes (42% vs. 21%, p = 0.0002). Analysis of endomyocardial biopsies obtained during the 1-year follow-up period demonstrated that women averaged more episodes of acute rejection than men (3.9 vs. 3.0, p = 0.009). While most episodes of rejection were mild, women were more likely than men to have episodes of moderate or severe rejection (14% vs. 5%, p = 0.012) and to be hospitalized for acute rejection (15% vs. 6%, p = 0.013). There were no significant differences in mortality.

CONCLUSIONS

Men were more likely than women to be older and to have diabetes, dyslipidemia, hypertension, and a history of smoking. Women were more likely to experience moderate or severe allograft rejection and to be hospitalized for acute rejection. Future investigation of the reasons for these gender differences is warranted and may improve clinical care of women undergoing cardiac transplantation.