Abstract
Background & Aims
Women are significantly less likely than men to receive a liver transplant and more likely to die on the waitlist. We investigated potential reasons for these disparities, including match run positions and declined organs due to small stature of female recipients.
Methods
We analyzed data from the United Network of Organ Sharing registry of candidates placed on the waitlist from May 10, 2007 through June 17, 2013. Primary outcomes included: ranked in first position on a match run, having an organ declined while in first position, declining an organ while in first position because of size mismatch between donor and recipient (body surface area discordance), and death or becoming too sick for liver transplantation.
Results
Among 64,995 patients on the waitlist for liver transplantation, 23.1% of men and 15.6% of women received exception points (P<.001). Women listed without exception points were less likely than men to be ranked first (odds ratio [OR], 0.93; 95% CI, 0.88–0.99). Women who achieved a first position were more likely to decline an organ than men (OR, 1.15; 95% CI, 1.06–1.26); this difference was reduced after we accounted for recipient body surface area (OR, 1.08; 95% CI, 0.98–1.19). Women with a single liver decline were more likely than men with a single liver decline to die or become too sick for transplantation (OR, 1.26; 95% CI, 1.12–1.41). The difference was reduced after we accounted for exception points (OR, 1.16; 95% CI, 1.12–1.21) and recipient body surface area (OR, 1.01; 95% CI, 0.96–1.06).
Conclusion
In an analysis of data from the United Network of Organ Sharing registry, we found that women when compared to men on the waitlist for liver transplantation. are disadvantaged by an imbalance in exception point allocation and organ decline because of small stature.
Keywords: gender disparity, organ size, UNOS, Organ Procurement and Transplantation Network
Introduction
Gender disparities in health-related outcomes and access to care are well described.1,2 The field of liver transplantation (LT) is no exception. In an effort to establish an equitable LT allocation process, the Model for End-Stage Liver Disease (MELD) score was adopted in 2002.3 Despite this, women remain significantly less likely than men to receive a transplant and more likely to die on the waitlist when compared to men.4–6
The process of LT is complex. Each time an organ becomes available, a list of all potential recipients is generated by the Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS); this list is referred to as a match run. Seventy percent of organs are allocated to candidates in the first three positions on a match run, making access to the highest match run positions a potentially important contributor to LT gender disparities. 7 With few exceptions, a candidate must have the highest MELD score for a given blood type in their local geographic area to move to the top of a match run. In select patients, in whom the MELD score is thought to underestimate disease severity, additional exception points can be allocated, increasing the MELD score. The most common indication for receipt of exception points is hepatocellular carcinoma (HCC).
Being in the highest ranked positions does not assure that one will receive a LT. An organ offer can be declined by the patient and/or the transplant team. Factors such as organ size, perceived recipient acuity, and organ quality all contribute to the decision to accept or decline an organ for a given candidate.
The reasons for the gender disparity in LT have not been fully elucidated. Among the leading hypotheses are limitations in the ability of creatinine, a component of the MELD score, to accurately predict renal function in women who on average have lower muscle mass.8–10 Donor-recipient size mismatch has also been proposed as a potential explanation.6 To better understand why women are transplanted less, and die more frequently, this study explored the root causes of these disparities. We hypothesized that men are more likely to receive exception points due to the demographics of HCC, thereby achieving higher match run positions. Furthermore, when women do achieve top positions they are passed over because of size mismatch.
Methods
Study Population and Data Source
A retrospective cohort study of patients waitlisted for LT in the US using data from the OPTN was conducted. OPTN manages the nation’s organ transplant system, and is responsible for matching organ donors to recipients.11 UNOS makes available for research a list of all candidates on a match run who received the organ, as well as those who were ranked ahead of the candidate who ultimately accepted the organ. Match run data became available for research purposes on May 10, 2007. Additional data on waitlist candidates and their donors were obtained from the Standard Transplant Analysis and Research (STAR) files from the same study period.
All adult candidates who were ever on a match run from May 10, 2007 through June 17, 2013, were evaluated for study inclusion. Given the different criteria for waitlisting, organ allocation, and organ acceptance patterns for multi-organ transplantation, re-transplantation, and status 1 recipients (fulminant hepatic failure), these patients were excluded from the analysis. Waitlist candidates who were listed at multiple centers were included only once; either at the center where they received an organ offer in first position or at the center where they were first waitlisted if they never received an organ offer.
Outcomes
The primary outcomes were: 1) being ranked in first position on a match run, 2) having an organ offer declined while in first position, 3) having an organ offer declined in the first position because of donor-recipient size mismatch defined by body surface area discordance (BSA) and, 4) death or becoming too sick for LT.
The secondary outcomes were: 1) being ranked in positions two or three on a match run, 2) having an organ offer declined while in positions two or three on a match run, 3) and having an organ offer declined in first position because of size discordance (height, body mass index (BMI), estimated liver weight (ELW), and estimated liver volume (ELV) between donor and potential recipient.
Match run position
Each time an organ becomes available the candidate ranked in first position is guaranteed to be offered the organ. Declined organs are then offered to the candidate in the next position. Organs declined by multiple candidates and/or transplant teams may be less desirable organs, therefore our primary outcome focused on being in the first position on a match run.
A waitlist candidate may achieve a match run position on multiple occasions while listed for LT. Statistical models included only the first time a patient achieved rank positions one, two, or three.
Organ declines
Organs declined for or by candidates for any reason were included in the outcome of organ decline in the first three positions.
Size discordance
Measures of donor-recipient size discordance explored included a twenty percent discordance in BSA (primary outcome measure), weight, height, BMI, ELW, and ELV between donor and recipient. The 20% threshold was selected since body surface area index BSAi (BSA donor/BSA recipient) greater than 1.24, or a 24% increase, has been shown to impact graft survival.12 ELW, ELV, and BSAi calculations utilized recipient and donor height and weight data as previously described.13–15
Each time an organ is declined, a transplant center is required to enter a code into the UNOS database describing a reason for the decline. Secondary study outcomes included additional measures of donor-recipient size discordance including having an organ declined in first position because of UNOS code 831 for donor-recipient size mismatch. UNOS refusal codes haven not been validated, but have been previously used for research.
Too sick for LT and mortality
Removal from the waitlist because of death or becoming too sick for LT was based on UNOS codes.
Covariates
Covariates included gender, age, race/ethnicity, blood group, liver disease diagnosis, donor weight, donor height, laboratory MELD score (including creatinine, INR, and bilirubin), allocation MELD score (includes exception points), UNOS region, and UNOS donor service area (DSA). Exception point status was extracted for each patient.
Recipient weight and height at the time of transplant was only present for those candidates who underwent transplant, therefore height and weight at listing were used for analyses including anthropometric measures. Mean height and weight at transplant was nearly identical height and weight at listing for those candidates who underwent transplant (data not shown).
Ascites grade is a potential confounder in the association between gender and organ refusal because of donor-recipient size mismatch. Smaller recipients may be considered for an organ from a larger donor if they had a history of moderate to large volume ascites. Therefore, ascites grade (none, trace, moderate to large) was also evaluated as a potential confounder.
Statistical Analysis
Baseline characteristics are presented as percentages, means for normally distributed variables, and medians for non-normally distributed variables. Chi squared tests were used to compare categorical variables and rank sum and t-tests used to compare continuous variables.
A previous study demonstrated significant differences in gender disparities by region, and there is significant geographic variability in the probability of transplantation and waitlist removal that varies not only by region but donor service area.5 Therefore, multilevel mixed effects logistic regression was used as the primary statistical approach to allow for clustering of the data by UNOS DSA.
Covariates selected a priori for inclusion in the multivariable analysis included region, and the waitlisted patient’s blood type, race/ethnicity, and liver disease diagnosis. To determine if recipient size would attenuate a disparity in organ declines between men and women, measures of recipient size were added to multivariable models used to explore organ declines. An interaction was explored between recipient BSA and gender in order to determine if any association between smaller stature and organ declines was specific to women. Recipient BSA was evaluated continuously and in tertiles. Tertiles were named small, average, and large.
Women might be advantaged by living donor and split liver transplantation, therefore gender differences in the numbers of these transplants were explored.16
Results
During the study period, 64,995 candidates were listed for LT (Figure 1). Overall, 42.4% of women and 49.7% of men underwent LT during follow-up (p<0.001). The absolute difference in proportion of men and women receiving LT in each region was signficantly different and ranged from 4.6% to 13.9% (p<0.001). Of the candidates listed for LT, 23.1% of men and 15.6 % of women received exception points (p<0.001). 73% of the exception points were granted for HCC. Women in first position had higher laboratory MELD scores than men (26 vs 25 p<0.001). Women in first position had significantly lower creatinine (1.2 vs 1.3, p<0.001), but significantly higher bilirubin (7.5 vs 5.7, p<0.001) and INR than men (2.0 vs 1.9, p<0.001) (Supplemental Table 1).
Figure 1.
Primary outcomes
Assocation between gender and acheving the highest match run positions
10,714 candidates (16.5%) achieved first position on a match run during the study period (Figure 1). Women were signifcantly less likely than men to receive exception points at each position (Supplemental Table 1).
Women without exception points were significantly less likely than men to achieve first position on a match run (OR: 0.93, 95% CI: 0.88–0.99). However, women with exception points were just as likely as men to achieve first position (OR: 0.98, 95% CI: 0.94–1.04) (Table 2). Women with exception points were significantly less likely than men to achieve positions two and three, while those without exception points were significantly less likely to occupy position two on a match run (Table 2).
Table 2.
Association between gender, highest match run position, an organ declines
| Achieved Match Run Position | Organ Declined at Match Run Position | |||
|---|---|---|---|---|
|
With Exception Points Multivariable OR Men vs Women (95% CI) |
Without Exception Points Multivariable OR Men vs Women (95% CI) |
All Candidates Multivariable OR Men vs Women (95% CI) |
Multivariable OR Men vs Women (95% CI) | |
| Position 1 | 0.98 (0.94–1.04) | 0.93 (0.88–0.99) | 0.97 (0.92–1.01) | 1.16 (1.06–1.26) |
| Position 2 | 0.94 (0.89–0.98) | 0.93 (0.88–0.98) | 0.934 (0.89–0.98) | 1.30 (1.20–1.41) |
| Position 3 | 0.94 (0.89–0.99) | 0.95 (0.89–1.01) | 0.94 (0.89–0.99) | 1.31 (1.19–1.44) |
Multivariable models adjusted for blood type, diagnosis, ethnicity/race, region and DSA
Association between gender and declining an organ offer in highest match run positions
Of the 10,714 candidates who achieved first position, 5,360 candidates had at least one organ offer declined (Figure 1); 48.8% of men and 52.3% of women were declined an organ while in the first position (p<0.001). In multivariable models, women were significantly more likely than men to have an organ offer declined while in the first position (OR: 1.16, 95% CI: 1.06–1.26), second position (OR: 1.30, 95% CI: 1.20–1.41) or third position (OR 1.31, 95% CI: 1.19–1.44) (Table 2).
Mediation of the disparity in organ declines by measures of waitlist candidate body size
The contribution of recipient size to organ declines was examined by adding various measures of size to the multivariable model exploring gender differences in organ declines while in first position on a match run. When recipient BSA, height, ELW, or ELV were added to the model, there was no longer a significant association between gender and having an organ offer declined while in the first position (Supplemental Table 2). The disparity was not attenuated significantly by inclusion of BMI or weight (Supplemental Table 2).
Association between gender and organ declines because of size
Organ offer declines were more frequent for women of smaller stature than for men of smaller stature (OR: 1.18, 95% CI: 1.02–1.37) (Table 3). On average women of smaller stature declined while in first position were significantly smaller than men (158.9 cm vs 166.4 cm, p <0.001). Men of smaller stature were also significantly more likely to have an organ offer declined when compared to men of average stature (OR: 1.17, 95% CI: 1.01–1.36 CI) (Table 3). These finding were similar when explored in candidates without exception points (data not shown).
Table 3.
Association between gender and organ declines because of size mismatch (BSA)
| Univariable OR (95% CI) | Multivariable OR (95% CI) | |
|---|---|---|
| Ref group: Small men | ||
| Small women (n=2,391) | 1.14 (0.99–1.33) | 1.18 (1.02–1.37) |
| Average women (n=1,014) | 0.82 (0.69–0.98) | 0.84 (0.70–1.00) |
| Large women (n=335) | 0.74 (0.58–0.96) | 0.77 (0.59–0.99) |
| Average men (n=2,559) | 0.86 (0.75–0.99) | 0.85 (0.74–0.99) |
| Large men (n=3,230) | 0.88 (0.74–0.99) | 0.89 (077–1.02) |
| Ref group: Average sized men (BSA) | ||
| Small men (n=1,181) | 1.16 (1.00–1.34) | 1.17 (1.01–1.36) |
| Small women (n=2,391) | 1.33 (1.19–1.49) | 1.38 (1.22–1.56) |
Multivariable models adjusted for blood type, diagnosis, ethnicity/race, region and DSA
Of the 5,360 candidates who had organ offers declined in first position, 1,922 candidates had BSA discordance with their potential donor; 31.2% of men and 43.9% of women (Figure 1). In multivariable models, women declined in first position were significantly more likely to have BSA discordance with their potential donor than men (OR: 4.81, 95% CI: 4.09–5.64). When ascites grade was added to the model, women declined in first position remained significantly more likely to have BSA discordance with their potential donor than men (OR: 4.65, 95% CI: 3.85–5.62) (Supplemental Table 3).
In multivariable analysis, UNOS refusal code 831 for donor-recipient size mismatch was associated with female gender in those declined in first position (OR: 2.29, 95% CI: 1.96–2.68). Weight (OR: 2.10, 95% CI 1.8–2.44), ELW (OR: 4.25, 95% CI: 3.51–5.16), and ELV (OR: 4.81, 95% CI 3.53–5.19) discordance between recipient and donor were also associated with female gender in candidates declined in first position. BMI discordance was not associated with gender in candidates declined in first position (Supplemental Table 3). There were only 39 discordant height pairs therefore a multivariable analysis including height discordance was not performed.
The association between BSA discordance and gender was examined amongst those candidates who had organs accepted in first position. There was also a significant association between BSA discordance and gender in this group (OR: 4.57, 95% CI: 3.70–5.64).
Association between gender, organ declines, and becoming too sick for LT or death
Off all the candidates in the study 33.7% of women and 29.0% of men were removed from the waitlist for becoming too sick or death. Compared to men with one organ decline, women with one decline were significantly more likely to become too sick or die while awaiting LT (OR: 1.26, 95% CI: 1.12–1.41). Men with 2–4 declines were just as likely as men with one decline to die or to become too sick for LT (OR: 1.04, 95% CI: 0.96–1.14). However, women with 2–4 declines (OR: 1.17, 95% CI: 1.06–1.29) or 5 or more declines (OR: 1.34, 95% CI: 1.23–1.45) were significantly more likely than men with one decline to die or to become too sick for LT (Table 4).
Table 4.
Association between gender, organ declines, and becoming too sick for liver transplant or death
| Ref group: Men with 1 organ decline (n=5,017) | OR (95% CI) | P value |
|---|---|---|
| Women with 1 decline (n=2,485) | 1.26 (1.12–1.41) | <.001 |
| Men with 2–4 declines (n=7,089) | 1.04 (0.96–1.14) | .330 |
| Women with 2–4 declines (n=3,745) | 1.17 (1.06–1.29) | .003 |
| Men with 5 or more declines (24,597) | 1.18 (1.10–1.28) | <.001 |
| Women with 5 or more declines (n=14,098) | 1.34 (1.23–1.45) | <.001 |
Multivariable models adjusted for blood type, diagnosis, ethnicity/race, region and DSA
Overall 15,224 candidates on the waitlist during the study period became too sick or died while awaiting LT. On univariable analysis women were significantly more likely than men to die or become too sick for LT (OR: 1.16, 95% CI: 1.12–1.21). This disparity remained in the standard multivariable analysis adjusting for blood type, diagnosis, ethnicity/race, region, and DSA (OR: 1.13, 95% CI: 1.09–1.18). When exception point status was added to the model the OR was significantly attenuated (1.05, 95% CI: 1.005–1.09). Subsequently, when recipient BSA was added to the multivariable model the disparity was no longer significant (OR: 1.01, 95% CI: 0.96–1.06) (Figure 2).
Figure 2.
Exception Point Status and Size Account for Gender Disparitiy in Death or Becoming Too Sick for LT
We questioned whether gender differences in LT might be made up for by living donor and split donor LT. Women were just as likely as men to receive a split donor (men=784 vs women =712, p=0.54) and trended toward less likely to receive living donor LT (men=651 vs women=510, p=0.07).
Discussion
LT is the sole lifesaving treatment for patients with ESLD. Despite efforts to ensure an equitable and objective allocation system, women continue to be less likely than men to receive LT, a disparity that has widened in the MELD era.4–6 The odds of death or waitlist removal were 16% higher for women than men during this study period; an observation first noted in 2008 by Moylan et al.4 In this study, we show that women are less likely than men to make it to the highest positions on a match run, particularly those women without exception points. Those women who do make it to the highest positions are more likely than men to have organs declined. This disparity in organ offer declines was more profound for small statured women than small statured men. Furthermore, organ declines were not without consequence, as the odds of death or being removed from the waitlist because of being too sick for LT were higher for women with organ declines than for men. The full gender disparity in waitlist mortality could be explained by exception point status and size. This work therefore elucidated two sources of gender disparity: 1) inability to achieve top match run positions and 2) organ declines. Here, the inability of women to achieve the top match run position is driven by exception point status while the disparity in organ declines is driven by women’s smaller stature.
Women without exception points were less likely than men to achieve first position on a match run and men were significantly more likely than women to obtain exception points at all three positions. The latter is likely due to the male predominance of HCC, the most frequent reason for receipt of exception points.18 Recently, it was reported that patients receiving exception points for HCC had lower mortality than candidates without HCC who were listed for LT with their native laboratory MELD score.19 In response to concern for over prioritization of patients with HCC, in October of 2015, there was a change made to the allocation policy. 20 Candidates with HCC are now required to wait 6 months on the waitlist before receiving exception points. While this change may serve to better balance overall waitlist mortality, it is unknown if this policy change will have any impact on the portion of the gender disparity in LT attributed to differences in exception point status.
In addition to disparities in match run position, women are also disadvantaged by organ declines. Organ declines for women are not without consequence. Women with even one organ decline were 26% more likely than men to die or be removed from the list. Previous work found that 84% of waitlist candidates who died or were removed from the waitlist because they were too ill had received at least one organ decline prior to removal.16 One potential explanation for the higher mortality and waitlist removal for women when compared to men is that women in first position were found to have significantly higher MELD scores than men. While this difference was not large, it is possible that MELD score in women was underestimated given the significantly lower serum creatinine for women at this position. This mortality difference may also be explained by higher numbers of men than women with HCC exception points given better short term outcomes of those with HCC after declining an offer.
Organ declines for small stature impacts both men and women. However, this disproportionately disadvantaged women who are more likely to have small stature. These results are similar to that of Lai et al. where height accounted for approximately 5% of the disparity observed.6 Donor-recipient size mismatch was four times more likely in women when compared to men in both those who had offers declined in first position and in those who had offers accepted. Small women in our study were on average 5′2″ and 142 pounds compared to small men who were 5′5″ and 147 pounds. The average donor size for candidates who had an organ offer accepted in first position was 5′6″ 176 pounds. The results suggest that the average donor is less often deemed appropriate for small women when compared to small men. The results were robust, being observed with multiple different measures of size and size mismatch. It is notable that there are women who were successfully transplanted despite apparent donor-recipient size mismatch. Additional research is needed to understand the decision-making.
This study has several strengths. It is the first to explore gender differences in match run positions and organs declined in the process of LT. This study captured all LT during the study period. Many of the covariates that could be associated with receiving an organ offer and gender were considered. While center specific practices may impact listing and therefore who receives an organ offer, these practices are not likely to be gender specific. Finally, we used multilevel modeling to account for correlation in decisions to list and to accept or decline organ offers within DSAs.
The study also has several limitations. Firstly, it was focused only on patients listed in the highest match run position to avoid potential bias that could result from including participants lower on the match run. There may be disparities at lower positions that could not be fully explored with the available data. The precise reason an organ is declined is difficult to determine from the UNOS database as the decline codes entered by each transplant center have not been validated and therefore may not be reliable.18 Height and weight measures for donor and recipient are more likely to be accurate and therefore our primary analysis focused on measures that included these variables. Finally, this cohort of patients pre-dates Share 35. However, because Share 35 does not impact the exception points system or the issue of size mismatch we hypothesize that these disparities will continue despite this change in allocation policy.
We have demonstrated that inequalities in match run position and organ declines both contribute to the observed gender disparities in LT. These disparities have consequences; leading to higher rates of waitlist mortality and removal in women when compared to men. With the incidence of HCC increasing, the numbers of exception points granted to men on the waitlist is likely to grow. Therefore interventions that focus on the disparity in organ declines, including early consideration of living donor liver transplant, increased access to split-liver donors, and/or priority for livers from smaller donors should be considered. Moreover, it will be important to assess whether the disparities due to exception points continue with the new policy on receipt of exception points for patients with HCC.
Supplementary Material
Table 1.
Characteristics of study population
| Characteristics | Achieved first position | P value | Declined in first position | P value | ||
|---|---|---|---|---|---|---|
| Men 6,972 Frequency (%) | Women 3,742 Frequency (%) | Men 3,402 Frequency (%) | Women 1,958 Frequency (%) | |||
| ABO | ||||||
| O | 2,649 (38.0) | 1426 (38.1) | .560 | 1,351 (39.7) | 785 (40.1) | .901 |
| A | 2,694 (38.6) | 1402 (37.4) | 1,298 (38.2) | 732 (37.4) | ||
| AB | 480 (6.9) | 270 (7.2) | 215 (6.32) | 132 (6.7) | ||
| B | 1149 (16.5) | 644 (17.2) | 538 (15.8) | 309 (15.8) | ||
| Race | <.001 | <.001 | ||||
| White | 5,148 (73.8) | 2,510 (67.1) | 2,489 (73.2) | 1,273 (65.0) | ||
| Black | 637 (9.1) | 464 (12.4) | 317 (9.3) | 262 (13.4) | ||
| Hispanic | 809 (11.6) | 513 (13.7) | 405 (11.9) | 280 (14.3) | ||
| Asian | 278 (4.0) | 202 (5.4) | 151 (4.4) | 113 (5.8) | ||
| Other | 100 (1.4) | 53 (1.4) | 40 (1.2) | 30 (1.5) | ||
| Diagnosis | <.001 | <.001 | ||||
| HCV | 3,317 (47.6) | 1,235 (33.0) | 1,604 (47.2) | 698 (35.7) | ||
| Alcohol | 1,217 (17.5) | 374 (10.0) | 558 (16.4) | 177 (9.0) | ||
| HBV | 278 (4.0) | 78 (2.1) | 139 (4.1) | 40 (2.0) | ||
| NASH | 906 (13.0) | 751 (20.1) | 434 (12.8) | 352 (18.0) | ||
| PSC | 337 (4.8) | 154 (4.1) | 172 (5.1) | 86 (4.4) | ||
| Autoimmune | 98 (1.4) | 335 (9.0) | 50 (1.5) | 151 (7.7) | ||
| PBC | 62(0.89) | 284 (7.6) | 26 (0.8) | 130 (6.6) | ||
| Other | 757 (10.9) | 531(14.2) | 419 (12.3) | 324 (16.6) | ||
| Recipient size Measures | Men Mean (SD) | Women Mean (SD) | P value | Men Mean (SD) | Women Mean (SD) | P value |
| Height (cm) | ||||||
| Small | 167.3 (15.2) | 159.5 (9.6) | <.001 | 166.4 (15.6) | 158.9 (10.9) | <.001 |
| Medium | 175.2 (6.0) | 165.4 (6.1) | <.001 | 174.8 (6.0) | 164.6 (5.9) | <.001 |
| Large | 181.6 (6.7) | 169.3 (6.8) | <.001 | 181.5 (6.7) | 169.4 (6.7) | <.001 |
| Weight (kg) | ||||||
| Small | 67.0 (8.9) | 66.3 (10.6) | .083 | 65.5 (9.4) | 64.8 (10.4) | <.001 |
| Medium | 83.2 (6.8) | 89.5 (7.8) | <.001 | 82.2 (6.8) | 88.3 (7.9) | <.001 |
| Large | 107.3 (14.6) | 160.9 (12.7) | <.001 | 107.2 (15.4) | 111.2 (12.6) | <.001 |
| BSA (m2) | ||||||
| Small | 1.75 (0.16) | 1.68 (0.14) | <.001 | 1.72 (0.16) | 1.66 (0.02) | <.001 |
| Medium | 2.0 (0.06) | 1.97 (0.06) | <.001 | 1.97 (0.06) | 1.95 (0.07) | <.001 |
| Large | 2.27 (0.14) | 2.20 (0.10) | <.001 | 2.27 (0.15) | 2.19 (0.10) | <.001 |
| Recipient MELD | Men Median | Women Median | P value | Men Median | Women Median | P value |
| Laboratory MELD | 25 | 26 | <0.001 | 24 | 26 | 0.01 |
| Allocation MELD | 28 | 28 | <0.001 | 28 | 29 | 0.08 |
Acknowledgments
Funding Source: Supported by research funding from the National Institutes of Health (F32 DK108527 to L.N., K23 DK090209 to K.F., K24 DK078228 to J.L.
Footnotes
Conflict of interest statement: No author has a conflict of interest
Authors’ contribution:
Conception or design of the work: L.N., K.F., D.G., J.L.
Data collection: L.N., D.G.
Data analysis and interpretation: L.N., K.F., D.G., P.A., M.B., J.L.
Drafting the article: L.N., K.F, D.G., J.L.
Critical revision of the article: L.N., K.F., D.G., P.A., J.L.
Final approval of the version to be published: L.N., K.F., D.G., P.A., M.B., J.L.
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