Abstract
Background
Survival for heart transplant recipients with type 2 diabetes mellitus is reduced; however, the effect of donor diabetes in this cohort is unknown. We examined the impact of donor diabetes status on long-term outcomes among diabetic heart transplant recipients.
Methods
The United Network for Organ Sharing database was queried to identify adult diabetic recipients undergoing single-organ heart transplantation between 2005 and 2025. The primary outcome was 10-year all-cause mortality, assessed after propensity score matching on 26 variables in a Cox proportional hazards model. Secondary outcomes included 30-day mortality, dialysis requirement, stroke, permanent pacemaker implantation, and length of stay. Median follow-up time was 7.05 years (95% CI 7.00-7.18).
Results
Of 13,091 heart transplant recipients identified, 540 (4%) received a diabetic donor heart and 12,551 (96%) received a non-diabetic donor heart. Recipients in the diabetic donor group were older (60.0 years [IQR 54.0-65.0] vs 59.0 [52.0-64.0], p < 0.001) and had shorter waitlist times (44.5 days [IQR 14.0-185.5] vs 60.0 [17.0-213.0], p = 0.02). Donors with diabetes were older (41.0 years [IQR 34.0-48.0] vs 32.0 [23.0-41.0], p < 0.001), had a higher prevalence of hypertension (55.9% vs 15.2%, p < 0.001), and were more likely to have donor-recipient sex mismatch (26.9% vs 21.5%, p = 0.003). Propensity score matching produced 539 pairs. In the matched cohort, 10-year survival was lower among recipients of diabetic donor hearts compared with non-diabetic donor hearts (48.5% vs 57.0%, adjusted HR: 1.26, 95% CI: 1.00-1.59, p = 0.04). Secondary outcomes were similar between groups.
Conclusion
Diabetic heart transplant recipients experience worse long-term survival when a diabetic donor heart is utilized.
Keywords: Heart transplantation, Donor diabetes, Recipient diabetes, Post-transplant survival
Background
Heart transplantation is the gold standard therapy for end-stage heart failure. To optimize postoperative outcomes, numerous donor and recipient factors associated with increased risk of postoperative complications have been identified.1, 2, 3, 4, 5 Of these, recipient pre-transplant type 2 diabetes mellitus (DM) has also been previously investigated, given its potential impact on end-organ dysfunction. While one large registry analysis reported similar outcomes among recipients with uncomplicated DM, multiple subsequent studies have demonstrated worse short- and long-term survival in this recipient population.6, 7, 8, 9, 10 Although less extensively studied, donor diabetes status has also been examined. Hearts from diabetic donors have been historically considered higher risk with lower rates of acceptance at the donor site.1, 11 Nonetheless, with the persistent shortage of available donor organs, these hearts have been increasingly utilized for transplant and have shown similar postoperative outcomes.12, 13
Whether outcomes associated with diabetic donor hearts remain comparable in diabetic recipients remains unclear. Prior studies in solid organ transplantation have shown that outcomes among diabetic recipients vary according to donor diabetes status; however, this interaction has not been evaluated in the heart transplant population.14, 15, 16 Given the increasing utilization of potentially higher-risk organs in an already higher-risk recipient cohort, we sought to investigate the impact of donor diabetes status on short- and long-term outcomes in diabetic heart transplant recipients.
Materials and methods
Data source
This study used the United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research file, which included data on organ donations, transplants, and new listings through June 30, 2025. We identified adult heart transplant recipients ≥ 18 years with a history of preoperative DM between January 1, 2005, and June 30, 2025. Exclusion criteria were multiorgan transplants, transplants following donation after circulatory death, and unknown donor or recipient diabetes status. Patients were stratified based on whether they received a heart from a diabetic donor or not (Figure 1).
Figure 1.
Trends in diabetic donor heart usage among all heart transplants between 2005 and 2025.
Baseline characteristics and postoperative outcomes were defined according to standard UNOS definitions. Patients with prior cardiac surgery or heart transplantation were categorized as having had a prior sternotomy. Donor to recipient predicted heart mass ratio was calculated as previously described and used as a surrogate for donor-recipient size mismatch.17, 18, 19 Preoperative functional status of the recipient was defined using the Karnofsky Performance Scale Index as previously described (Supplemental Table 1).20, 21 The Institutional Review Board at Cedars-Sinai Medical Center approved this study with a waiver of informed consent (STUDY00001188, approved on 11/15/2024).
Primary and secondary outcomes
Our primary outcome was survival at 10 years post-transplant. Median follow-up was 7.05 years (95% confidence interval [95% CI] 7.00-7.18). Secondary outcomes included the following early post-transplant outcomes: 30-day mortality, new in-hospital dialysis requirement, in-hospital permanent pacemaker implantation, in-hospital stroke, and post-transplant hospital length of stay.
Statistical analysis
Baseline donor and recipient characteristics were reported as median with IQR for continuous variables and proportions for categorical variables. Unadjusted comparisons between groups were performed using the Student t test or Wilcoxon signed-rank test for continuous variables depending on variable distribution. Pearson’s chi-square test was performed for categorical variables. Kaplan-Meier survival curves were generated for time-to-event analysis. The following categorical variables contained missing data and were marked as unknown in the analysis: history of cerebrovascular accident (0.07%) and pre-transplant recipient functional status (4.32%). The following continuous variables contained missing data and were addressed with simple imputation of the median value of the cohort: recipient body mass index at transplant (BMI, 0.02%), recipient creatinine at transplant (0.15%), recipient bilirubin at transplant (0.67%), and graft ischemic time (0.86%).
Propensity score matching was performed for adjusted analyses accounting for differences between study groups in clinically relevant baseline characteristics. Patients were matched 1:1 using greedy nearest-neighbor matching on the logit of the propensity score. We used a caliper width equal to 0.1 times the standard deviation of the logit. Adequate covariate balance was confirmed with computed standardized mean differences. A cutoff of < 0.10 was used to demonstrate adequate covariate balance.
Secondary outcomes between matched groups were compared using McNemar’s test for categorical variables and the Wilcoxon signed-rank test for continuous variables. Doubly robust adjusted survival analysis was performed using Cox proportional hazards regression and Kaplan-Meier survival analysis of the matched cohort. All analyses were performed using SAS version 9.4 (SAS Institute Inc). Statistical significance was set at p < 0.05.
Results
Among all single-organ heart transplants following donation after brain death between 2005 and 2025, the percentage of cases utilizing diabetic donor hearts increased from 2.68% in 2005 to 7.90% in 2025 (Figure 1). After excluding non-diabetic recipients, 13,091 adults undergoing single-organ heart transplant with a preoperative DM diagnosis were included in our analysis. Of these, there were 12,551 non-diabetic donors and 540 diabetic donors. Before matching, recipients who received their organ from a diabetic donor were older (60.0 years [IQR 54.0-65.0] vs 59.0 [IQR 52.0-64.0], p < 0.001), more often of white race (65.7% vs 60.7%, p = 0.02), had higher body mass index (29.1 kg/m2 [IQR 26.1-32.7] vs 28.7 [IQR 25.4-32.3], p = 0.02), more commonly had blood type O (53.9% vs 49.0%, p = 0.03), and remained on the waiting list for less time (44.5 days [IQR 14.0-185.5] vs 60.0 [17.0-213.0], p = 0.02). Recipients with diabetic donors were less likely to be listed status 1A in the pre-2018 allocation system (25.9% vs 34.2%, p < 0.001) and more likely to be listed status 3 (8.7% vs 6.1%, p = 0.01) and status 4 (10.9% vs 6.4%, p < 0.001) in the current allocation system. Regarding donor characteristics, the donor DM group was older (41.0 years [IQR 34.0-48.0] vs 32.0 [IQR 23.0-41.0], p < 0.001), had a higher prevalence of hypertension (55.9% vs 15.2%, p < 0.001), and more likely to have donor-recipient sex mismatch (26.9% vs 21.5%, p = 0.003; Table 1). Of note, no statistically significant differences were observed in preoperative mechanical circulatory support or preoperative functional status. The remainder of baseline recipient and donor characteristics are outlined in Table 1.
Table 1.
Baseline Characteristics of Diabetic Heart Transplant Recipients Stratified by Donor Diabetes Status Before and After Propensity Score Matching
| Non-Diabetic Donor (n = 12,551) | Diabetic Donor (n = 540) | P value | Non-Diabetic Donor (n = 539) | Diabetic Donor (n = 539) | SMD | ||
|---|---|---|---|---|---|---|---|
| Recipient | |||||||
| Age (years) | 59.0 (52.0, 64.0) | 60.0 (54.0, 65.0) | <0.001 | 60.0 (54.0, 66.0) | 60.0 (54.0, 65.0) | −4.43% | |
| Male Sex | 9,823 (78.3%) | 407 (75.4%) | 0.11 | 410 (76.1%) | 406 (75.3%) | −1.73% | |
| White Race | 7,619 (60.7%) | 355 (65.7%) | 0.02 | 355 (65.9%) | 354 (65.7%) | −0.39% | |
| Body Mass Index (kg/m2) | 28.7 (25.4, 32.2) | 29.1 (26.1, 32.7) | 0.02 | 29.2 (25.8, 32.6) | 29.1 (26.0, 32.7) | 1.04% | |
| Ischemic Cardiomyopathy | 5,814 (46.3%) | 242 (44.8%) | 0.49 | 248 (46.0%) | 242 (44.9%) | −2.24% | |
| Pre-Transplant VAD/TAH | 5,471 (43.6%) | 219 (40.6%) | 0.16 | 208 (38.6%) | 219 (40.6%) | 4.17% | |
| History of CVA | 884 (7.0%) | 45 (8.3%) | 0.26 | 49 (9.1%) | 45 (8.3%) | −2.63% | |
| Creatinine | 1.2 (1.0, 1.5) | 1.2 (1.0, 1.5) | 0.86 | 1.2 (1.0, 1.5) | 1.2 (1.0, 1.5) | −1.54% | |
| Pre-transplant hemodialysis | 329 (2.6%) | 10 (1.9%) | 0.27 | 10 (1.9%) | 10 (1.9%) | 0.00% | |
| Bilirubin | 0.7 (0.5, 1.0) | 0.7 (0.5, 1.0) | 0.76 | 0.6 (0.4, 1.0) | 0.7 (0.5, 1.0) | 0.25% | |
| Days on Waiting List | 60.0 (17.0, 213.0) | 44.5 (14.0, 185.5) | 0.02 | 46.0 (14.0, 172.0) | 45.0 (14.0, 187.0) | 3.57% | |
| Functional status | |||||||
| Mild limitation | 1,445 (12.0%) | 57 (11.2%) | 0.49 | 57 (10.9%) | 57 (11.2%) | 0.00% | |
| Moderate limitation | 3,565 (29.7%) | 170 (33.3%) | 0.12 | 162 (31.1%) | 169 (33.2%) | 2.82% | |
| Severe limitation | 7,006 (58.3%) | 283 (55.5%) | 0.12 | 302 (58.0%) | 283 (55.6%) | −7.08% | |
| Ventilator at Transplant | 210 (1.7%) | 11 (2.0%) | 0.52 | 6 (1.1%) | 11 (2.0%) | 7.45% | |
| IV inotropes at transplant | 4,938 (39.3%) | 206 (38.1%) | 0.58 | 215 (39.9%) | 205 (38.0%) | −3.81% | |
| ECMO at transplant | 329 (2.6%) | 12 (2.2%) | 0.57 | 8 (1.5%) | 12 (2.2%) | 5.50% | |
| IABP at transplant | 1,816 (14.5%) | 69 (12.8%) | 0.27 | 80 (14.8%) | 69 (12.8%) | −5.92% | |
| Listing Status | |||||||
| 1A (pre-2018 allocation) | 4,291 (34.2%) | 140 (25.9%) | <0.001 | 124 (23.0%) | 140 (26.0%) | 6.91% | |
| 1B (pre-2018 allocation) | 2,666 (21.2%) | 113 (20.9%) | 0.86 | 112 (20.8%) | 113 (21.0%) | 0.46% | |
| 2 (pre-2018 allocation) | 477 (3.8%) | 28 (5.2%) | 0.10 | 37 (6.9%) | 28 (5.2%) | −7.02% | |
| 1 | 555 (4.4%) | 19 (3.5%) | 0.32 | 16 (3.0%) | 19 (3.5%) | 3.14% | |
| 2 | 2,739 (21.8%) | 119 (22.0%) | 0.91 | 128 (23.7%) | 119 (22.1%) | −3.97% | |
| 3 | 768 (6.1%) | 47 (8.7%) | 0.01 | 55 (10.2%) | 47 (8.7%) | −5.07% | |
| 4 | 801 (6.4%) | 59 (10.9%) | <0.001 | 55 (10.2%) | 58 (10.8%) | 1.82% | |
| 6 | 254 (2.0%) | 15 (2.8%) | 0.23 | 12 (2.2%) | 15 (2.8%) | 3.56% | |
| Donor | |||||||
| Age | 32.0 (23.0, 41.0) | 41.0 (34.0, 48.0) | <0.001 | 41.0 (33.0, 50.0) | 41.0 (34.0, 48.0) | −1.07% | |
| Hypertension | 1,903 (15.2%) | 302 (55.9%) | <0.001 | 297 (55.1%) | 301 (55.8%) | 1.49% | |
| Sex Mismatch | 2,697 (21.5%) | 145 (26.9%) | 0.00 | 128 (23.7%) | 145 (26.9%) | 7.26% | |
| Size Mismatch | 1,817 (14.5%) | 79 (14.6%) | 0.92 | 65 (12.1%) | 79 (14.7%) | 7.64% | |
| LVEF < 50% | 287 (2.3%) | 13 (2.4%) | 0.85 | 11 (2.0%) | 12 (2.2%) | 1.28% | |
| Blood Type O | 6,152 (49.0%) | 291 (53.9%) | 0.03 | 289 (53.6%) | 290 (53.8%) | 0.37% | |
| Operative | |||||||
| Ischemic Time, hours | 3.4 (2.6, 3.9) | 3.4 (2.7, 4.1) | 0.07 | 3.5 (2.7, 4.1) | 3.4 (2.7, 4.1) | −2.89% | |
| Redo Sternotomy | 5,272 (42.0%) | 234 (43.3%) | 0.54 | 221 (41.0%) | 234 (43.4%) | 4.89% | |
| Transplant Year | |||||||
| 2005 | 380 (3.0%) | 11 (2.0%) | 0.19 | 12 (2.2%) | 11 (2.0%) | −1.28% | |
| 2006 | 470 (3.7%) | 16 (3.0%) | 0.35 | 17 (3.2%) | 16 (3.0%) | −1.08% | |
| 2007 | 494 (3.9%) | 10 (1.9%) | 0.01 | 15 (2.8%) | 10 (1.9%) | −6.17% | |
| 2008 | 424 (3.4%) | 15 (2.8%) | 0.45 | 13 (2.4%) | 15 (2.8%) | 2.33% | |
| 2009 | 472 (3.8%) | 16 (3.0%) | 0.34 | 15 (2.8%) | 16 (3.0%) | 1.11% | |
| 2010 | 464 (3.7%) | 25 (4.6%) | 0.26 | 31 (5.8%) | 25 (4.6%) | −5.02% | |
| 2011 | 508 (4.0%) | 13 (2.4%) | 0.06 | 10 (1.9%) | 13 (2.4%) | 3.85% | |
| 2012 | 519 (4.1%) | 21 (3.9%) | 0.78 | 18 (3.3%) | 21 (3.9%) | 2.98% | |
| 2013 | 514 (4.1%) | 21 (3.9%) | 0.81 | 16 (3.0%) | 21 (3.9%) | 5.10% | |
| 2014 | 596 (4.7%) | 25 (4.6%) | 0.90 | 16 (3.0%) | 25 (4.6%) | 8.74% | |
| 2015 | 605 (4.8%) | 23 (4.3%) | 0.55 | 25 (4.6%) | 23 (4.3%) | −1.80% | |
| 2016 | 707 (5.6%) | 24 (4.4%) | 0.24 | 20 (3.7%) | 24 (4.5%) | 3.75% | |
| 2017 | 692 (5.5%) | 29 (5.4%) | 0.89 | 31 (5.8%) | 29 (5.4%) | −1.62% | |
| 2018 | 713 (5.7%) | 39 (7.2%) | 0.13 | 38 (7.1%) | 39 (7.2%) | 0.72% | |
| 2019 | 718 (5.7%) | 28 (5.2%) | 0.60 | 32 (5.9%) | 28 (5.2%) | −3.24% | |
| 2020 | 733 (5.8%) | 30 (5.6%) | 0.78 | 25 (4.6%) | 30 (5.6%) | 4.22% | |
| 2021 | 739 (5.9%) | 38 (7.0%) | 0.27 | 40 (7.4%) | 38 (7.1%) | −1.43% | |
| 2022 | 798 (6.4%) | 33 (6.1%) | 0.82 | 41 (7.6%) | 33 (6.1%) | −5.87% | |
| 2023 | 848 (6.8%) | 36 (6.7%) | 0.94 | 38 (7.1%) | 36 (6.7%) | −1.47% | |
| 2024 | 868 (6.9%) | 63 (11.7%) | <0.001 | 58 (10.8%) | 62 (11.5%) | 2.36% | |
| 2025 | 289 (2.3%) | 24 (4.4%) | 0.00 | 28 (5.2%) | 24 (4.5%) | −3.46% | |
Values are presented as median (IQR) or n (%). VAD/TAH: ventricular assist device or total artificial heart, CVA: cerebrovascular accident, ECMO: extracorporeal membrane oxygenation, IABP: intra-aortic balloon pump, LVEF: left ventricular ejection fraction.
In unadjusted analyses, the donor DM cohort exhibited worse 10-year survival compared to the non-diabetic donor group (45.05% vs 53.6%, p = 0.02; Figure 2). The diabetic donor group required postoperative dialysis more frequently (18.1% vs 14.3%, p = 0.01) and had longer post-transplant length of stay (18 days [IQR 12.0-28.0] vs 16.0 [IQR 11.0-25.0], p = 0.004). Thirty-day mortality (3.9% vs 3.5%, p = 0.59), postoperative permanent pacemaker requirement (3.7% vs 2.6%, p = 0.11), and stroke (4.6% vs 3.3%, p = 0.08) were similar between the diabetic donor and non-diabetic donor groups (Table 2).
Figure 2.
Cohort derivation from the United Network for Organ Sharing (UNOS) database.
Table 2.
Short-term Outcomes Before and After Propensity Score Matching.
|
Overall Cohort |
Propensity-Matched Cohort |
|||||
|---|---|---|---|---|---|---|
| Non-Diabetic Donor (n = 12,551) | Diabetic Donor (n = 540) | P-value | Non-Diabetic Donor (n = 539) | Diabetic Donor (n = 539) | P-value | |
| 30-day mortality | 434 (3.5%) | 21 (3.9%) | 0.59 | 22 (4.1%) | 20 (3.7%) | 0.76 |
| Dialysis | 1793 (14.3%) | 98 (18.1%) | 0.01 | 84 (15.6%) | 97 (18.0%) | 0.29 |
| Pacemaker | 323 (2.6%) | 20 (3.7%) | 0.11 | 13 (2.4%) | 20 (3.7%) | 0.22 |
| Stroke | 408 (3.3%) | 25 (4.6%) | 0.08 | 15 (2.8%) | 25 (4.6%) | 0.11 |
| Length of stay (days) | 16.0 (11.0, 25.0) | 18.0 (12.0, 28.0) | 0.00 | 16.0 (11.0, 23.0) | 18.0 (12.0, 28.0) | 0.002 |
Propensity score matching was performed on 26 preoperative and operative variables, resulting in 539 matched pairs (99.8% match). Covariate balance was acceptable with standardized mean differences < 10% across all matched variables (Table 1). Within the matched cohort, post-transplant length of stay was longer in the diabetic donor group (18 days [IQR 12.0-28.0] vs 16.0 [IQR 11.0-23.0], p = 0.002). No differences in 30-day mortality (3.7% vs 4.1%, p = 0.76), dialysis requirement (18.0% vs 15.6%, p = 0.29), permanent pacemaker requirement (3.7% vs 2.4%, p = 0.22), or postoperative stroke (4.6% vs 2.8%, p = 0.11) were observed when comparing the matched cohorts. At 10-year follow-up, survival was lower among recipients of diabetic donor hearts compared with non-diabetic donor hearts (45.1% vs 54.0%; adjusted HR 1.26, 95% CI 1.00-1.59; p = 0.04; Figure 3, Figure 4, Supplemental Table 2). A sensitivity analysis adjusting for center volume was performed given the independent association of donor age in our Cox model and prior reports of older donor utilization at higher-volume centers. Centers were categorized into tertiles of annual heart transplant volume during the study period (1.2-6.94, 7.0-18.5, and 18.6-74.1 transplants/year). Donor diabetes remained associated with worse 10-year survival in this sensitivity analysis (adjusted HR 1.27, 95% CI 1.00-1.60, p = 0.04; Supplemental Table 3).
Figure 3.
Ten-year unadjusted survival in diabetic heart transplant recipients stratified by donor diabetes status (45% [95% CI 39.2%-51.7%] vs 53.6% [95% CI 52.4%-54.8%]; p = 0.02).
Figure 4.
Ten-year adjusted survival of diabetic heart transplant recipients stratified by donor diabetes status, following propensity score matching on 26 preoperative and operative variables in a Cox proportional hazards model (45.1% vs 54.0%, adjusted HR: 1.26 [95% CI: 1.00-1.59], p = 0.04).
Discussion
DM is a common comorbidity in patients with chronic heart failure with a growing prevalence in heart transplant candidates.22 While prior studies have investigated the impact of donor and recipient diabetes statuses individually, the interaction between the 2 is unknown in the heart transplant population. Our study demonstrates that among diabetic recipients, donor diabetes is associated with worse long-term survival despite comparable early outcomes.
The deleterious effects of DM on cardiovascular physiology have been extensively investigated. Through metabolic derangements, pro-inflammatory signaling, and endothelial injury, diabetes promotes myocardial fibrosis and impaired coronary perfusion to ultimately yield both diastolic and systolic function of the native heart.23, 24, 25 While hearts from diabetic donors do not exhibit these overt signs of chronic diabetic heart failure, we hypothesize these donor organs may still contain aberrant (though clinically undetectable) molecular signatures that predispose the graft to subsequent injury when transplanted into a diabetic recipient. Multiple studies have implicated chronic post-transplant hyperglycemia in the pathogenesis of chronic graft failure through its effects on endothelial injury, microvascular inflammation, and ultimately cardiac allograft vasculopathy (CAV).26, 27, 28 Still, adequate post-transplant glycemic control remains a clinical challenge affecting up to 40% of recipients at 1-year follow-up in institutional case series.29, 30, 31, 32 Interestingly, while long-term follow-up was limited, Munshi and colleagues demonstrated significantly worse glycemic control among recipients with pre-transplant DM compared to those with no prior diagnosis of DM.30 Thus, our findings may reflect a potential 2-hit phenomenon: the introduction of a molecularly abnormal donor organ into a pathogenic environment that accelerates graft decline.
This phenomenon has been previously explored in the solid organ literature. Like diabetic heart transplant recipients, lung, kidney, and liver transplant recipients with pre-transplant DM experience worse long-term survival.33, 34 Donor diabetes has also been linked to adverse outcomes in kidney and lung transplantation, although the interaction between donor and recipient diabetes status has yielded heterogeneous results. In lung transplantation, subgroup analyses suggest that the excess mortality associated with donor diabetes may be attenuated among diabetic recipients.35 In kidney transplantation, however, donor diabetes appears to compound the risk associated with recipient diabetes.14, 15, 16 Our study adds to this literature as the first to examine the interplay between donor and recipient diabetes status in the heart transplant population. While our findings are consistent with those reported in kidney transplantation, the divergence that we observed from the lung transplant population suggests that the response of allografts from diabetic donors in a diabetic recipient environment may be organ-specific.
Limitations
Our study has several limitations. First, donor DM was defined in our analysis based on past medical history per standard UNOS criteria, rather than a numerical cutoff such as hemoglobin A1c (HbA1c). While this approach considers the long-term effects of DM beyond the 3-month period reflected by HbA1c measurements, we are unable to comment on the severity of donor DM in our analysis. The missingness of the variable for donor HbA1c in the UNOS database also limited its use in the analysis of our cohort. Second, our study lacks clinical granularity regarding the longitudinal glycemic control of recipients after transplantation. While we hypothesize that this carries implications on long-term graft function, it is unclear what glucose-lowering agents were utilized and the subsequent success of these interventions. Third, our study is unable to draw mechanistic conclusions to explain the observed differences in survival. While we hypothesize that diabetic donor hearts may be more prone to vascular injury and subsequent development of CAV, the lack of granular data on CAV and long-term graft rejection remains a key limitation of the UNOS database. Lastly, despite doubly robust statistical adjustment for potential confounding covariates, our study is subject to residual unmeasured confounding given its retrospective nature and the limited follow-up data in the UNOS database. Potentially significant areas include treatment of pre-transplant sensitization status, post-transplant immunosuppression strategies, and long-term management of comorbid metabolic disease.
Conclusions
Among diabetic heart transplant recipients, receipt of a diabetic donor heart is associated with worse 10-year survival. While the mechanism of this relationship is unclear, our findings highlight the importance of diligent postoperative surveillance. While the mechanism of this relationship is unclear, our findings highlight the importance of diligent postoperative surveillance and raise questions regarding the potential impact of long-term metabolic health on graft function. Future longitudinal studies examining markers of recipient metabolism may identify modifiable contributors to late graft failure and long-term survival.
Disclosure statement
None of the authors involved in this study have relevant financial relationships to disclose.
Conflicts of Interest statement
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
Allen A. Razavi and Aminah Sallam are supported by the National Institutes of Health for advanced heart disease research (T32HL116273).
Footnotes
Supplementary data associated with this article can be found in the online version at doi:10.1016/j.jhlto.2026.100631.
Appendix A. Supplementary material
Supplementary material
References
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