Older Kidney Transplant Research Articles

Evolving Trends in Kidney Transplant Outcomes Among Older Adults: A Comparative Analysis Before and During the COVID-19 Pandemic.

Advancements in medical technology, healthcare delivery, and organ allocation resulted in improved patient/graft survival for older (age ≥65) kidney transplant (KT) recipients. However, the recent trends in these post-KT outcomes are uncertain in light of the mounting burden of cardiovascular disease, changing kidney allocation policies, heterogeneity in candidates' risk profile, and the coronavirus disease 2019 pandemic. Thus, we examined secular trends in post-KT outcomes among older and younger KT recipients over the last 3 decades. We identified 73 078 older and 378 800 younger adult (aged 18-64) recipients using Scientific Registry of Transplant Recipients (1990-2022). KTs were grouped into 6 prepandemic eras and 1 postpandemic-onset era. Kaplan-Meier and Cox proportional hazards models were used to examine temporal trends in post-KT mortality and death-censored graft failure. From 1990 to 2022, a 19-fold increase in the proportion of older KT recipients was observed compared to a 2-fold increase in younger adults despite a slight decline in the absolute number of older recipients in 2020. The mortality risk for older recipients between 2015 and March 14, 2020, was 39% (adjusted hazard ratio [aHR] = 0.61, 95% confidence interval [CI], 0.50-0.75) lower compared to 1990-1994, whereas that for younger adults was 47% lower (aHR = 0.53, 95% CI, 0.48-0.59). However, mortality risk during the pandemic was 25% lower (aHR = 0.75, 95% CI, 0.61-0.93) in older adults and 37% lower in younger adults (aHR = 0.63, 95% CI, 0.56-0.70) relative to 1990-1994. For both populations, the risk of graft failure declined over time and was unaffected during the pandemic relative to the preceding period. The steady improvements in 5-y mortality and graft survival were disrupted during the pandemic, particularly among older adults. Specifically, mortality among older adults reflected rates seen 20 y prior.

A Comprehensive Review of Infections in Older Kidney Transplant Recipients

While a great deal of literature has been published in recent years on infections in kidney transplant (KT) recipients, there is a relative paucity of literature on infections and their impact on the graft and overall health of older KT recipients. We reviewed the most recent literature and guidelines in the field of kidney transplantation and summarized the current recommendations for physicians caring for older KT recipients at risk for infections. Older KT recipients are at an increased risk of infections during the first year post-KT resulting in readmission or other poor outcomes, compared to younger KT recipients. Immune senescence and frailty likely increase the risk for infections in older KT recipients during the first year post-KT when KT recipients are receiving a higher degree of immune suppressive therapy. Most common infections include urinary tract infections, bloodstream infections, cytomegalovirus reactivation or primary infection, and BK virus. A majority of older KT recipients survive and have a functioning graft at 1 year. KT can be a successful treatment for older adults on dialysis if post-transplant complications, including rejection and infection, can be appropriately managed. Despite this increased risk for infections, older KT recipients have a lower risk for all-cause mortality and death secondary to infections compared with patients on dialysis. Further studies on modification of immune suppression and prophylactic strategies are much needed in this high-risk KT population.

OLDER ADULT KIDNEY TRANSPLANT RECIPIENTS: THE LIVED EXPERIENCE OF ADAPTATION AND INTEGRATION

As the prevalence of end-stage renal disease increases in the United States, a growing number of adults aged 65 and over are receiving kidney transplants. While older adult recipients tend to fare well from a clinical standpoint, far less is known about their psychosocial wellbeing following transplantation. This study seeks to better understand the lived experience of older adult kidney transplant recipients, focusing on the ‘liminal’ period of adaptation following organ transplantation that has been reported elsewhere in the literature. Applying the hermeneutic phenomenology of philosopher Paul Ricoeur, the study explores the lived experience of 10 deceased donor kidney transplant recipients aged 65 and over. Guided by Ricoeur’s conceptual approach to identity as constituted through two forms, idem and ipse, preliminary findings suggest that despite expressing some distress around the ‘strangeness’ of integrating part of another into oneself (disruption of the idem sense of self), participants also constructed powerful narratives of resilience and coping that were rooted in the continuity of a deeply held ipse sense of identity over the life course. In particular, participants emphasized their ability to overcome adversity as an anchor of their ipse sense of self that enabled them to navigate the idem corporeal changes of transplantation. Moreover, they described kidney transplantation as a form of liberation, ultimately restoring their idem sense of self that had been profoundly disrupted by ‘machine life’ (time spent on dialysis). These findings will have significant implications for ensuring the provision of optimal support to older adult kidney transplant recipients.

POST-TRANSPLANT FUNCTIONAL STATUS TRAJECTORY AMONG ADULT KIDNEY TRANSPLANT RECIPIENTS

Frailty and disabilities are highly prevalent among kidney transplant (KT) recipients, but are not routinely measured in KT recipients. The Karnofsky Performance Scale (KPS) is a clinically perceived measure used to evaluate patient’s ability to manage daily activities, but little is known about its post-KT trajectories and its relationship to frailty and disability in KT recipients. We leveraged a cohort of 159,992 adult KT recipients from SRTR (1/2005-6/2018) and a cohort of 1,106 adult KT recipients from a prospective cohort study on aging and KT with recorded KPS (range 10%-100% integers). In each separate cohort, we used mixed effects models to assess differences in trajectories of KPS post-KT. In 159,992 KT recipients in SRTR, the mean unadjusted KPS score was 88.34% (95%CI: 88.28%, 88.40%) and declined at a rate of -0.59%/year (95%CI: -0.61%, -0.57%) post-KT, such that by 2-years post-KT the average was 87.00% (95%CI: 86.94%, 87.05%). Age at KT was associated with steeper decline in KPS (p0.05). KPS is a measure of functional status distinct from frailty, ADL, IADL, and SPPB at KT admission that declines with older age post-KT. Older KT recipients should be monitored closely for declines in physical function, and potentially undergo prehabilitation to improve functional status post-KT.

Outcomes in Older Kidney Transplant Recipients After Prior Nonkidney Transplants.

Recipients of nonkidney solid organ transplants (nkSOT) are living longer, and 11%-18% will develop end stage renal disease (ESRD). While our general inclination is to treat nkSOT recipients who develop ESRD with a kidney transplant (KT), an increasing number are developing ESRD at an older age where KT may not be the most appropriate treatment. It is possible that the risk of older age and prior nkSOT might synergize to make KT too risky, but this has never been explored. To examine death-censored graft loss and mortality for KT recipients with and without prior nkSOT, we used Scientific Registry of Transplant Recipients data to identify 42 089 older (age ≥65) KT recipients between 1995 and 2016. Additionally, to better understand treatment options for these patients and survival benefit of KT, we identified 5023 older (age ≥65) with prior nkSOT recipients listed for subsequent KT, of whom 863 received transplants. Compared with 41 159 older KT recipients without prior nkSOT, death-censored graft loss was similar (adjusted hazard ratio [aHR]: 1.13, 95% CI: 0.93-1.37, P = 0.2), but mortality (aHR: 1.40, 95% CI: 1.28-1.54, P < 0.001) was greater for older KT recipients with prior nkSOT. Nonetheless, in a survival benefit model (survival with versus without the transplant), among older prior nkSOT recipients, KT decreased the risk of mortality by more than half (aHR: 0.47, 95% CI: 0.42-0.54, P < 0.001). Older prior nkSOT recipients who subsequently develop ESRD derive survival benefit from KT, but graft longevity is limited by overall survival in this population. These findings can help guide patient counseling for this challenging population.

Early Hospital Readmission in Older and Younger Kidney Transplant Recipients

Background: Up to 31% of kidney transplant (KT) recipients experience early hospital readmission (EHR). We hypothesized that EHR among older KT recipients is higher than younger recipients due to increased comorbidities and higher prevalence of frailty. Methods: We identified 22,458 older (age ≥65) and 86,372 younger (18 to < 65) first-time KT recipients (December 1, 1999 – December 31, 2014) using United States Renal Data System data. We estimated the association between patient-level characteristics and EHR (30 days post-KT discharge) with modified Poisson regression among older and younger KT recipients, separately. We estimated the association between graft loss and mortality and EHR using Cox proportional hazards. Results: EHR was more common in older KT recipients (30.1 vs. 27.6%; p < 0.001). Risk factors for EHR that differed by recipient age included female sex, African American race, diabetes, smoking, dialysis vintage, donor age, and length of stay. Risk of graft loss associated with EHR was greater among older KT recipients (adjusted hazard ratio [aHR] 1.64, 95% CI 1.51–1.77, p < 0.001) than younger KT recipients (aHR 1.43, 95% CI 1.38–1.48, p < 0.001; interaction p < 0.01). However, the risk of mortality associated with EHR was greater among younger recipients (aHR 1.52, 95% CI 1.47–1.57, p < 0.001) than that in older ­recipients (aHR 1.40, 95% CI 1.34–1.47, p < 0.001; interaction p < 0.01). Conclusions: Older KT recipients are more likely to experience EHR and are at a higher risk of graft loss after EHR than younger recipients. Targeted interventions to prevent EHR and subsequent graft loss in this population should be identified.

Dementia and Alzheimer's Disease among Older Kidney Transplant Recipients.

Older patients with ESRD who receive a kidney transplant (KT) may develop post-KT dementia and Alzheimer's disease (AD) associated with their long-standing kidney disease and/or neurotoxic immunosuppressant agents. To investigate this possibility, we studied 40,918 older (aged ≥55 years) KT recipients (January 1, 1999 to December 31, 2011) linked to Medicare claims through the US Renal Data System. We estimated dementia and AD risk (cumulative incidence) and studied factors associated with these sequelae using competing risks models. We estimated the risk of death-censored graft loss and mortality after developing dementia or the AD subtype of dementia, separately, using adjusted Cox proportional hazards models. Older recipients had a 10-year dementia risk ranging from 5.1% for recipients aged 55-60 years to 17.0% for recipients aged ≥75 years; 10-year AD risk ranged from 1.0% to 6.7%, respectively. The strongest predictors for dementia and AD were older recipient age and pretransplant diabetes. The 10-year graft loss risk was 28.8% for those who did not develop dementia and 43.1% for those who did, and the corresponding mortality risks were 55.7% and 89.9%, respectively. Older recipients with dementia had a 1.52-fold (95% confidence interval, 1.39 to 1.68) increased risk of graft loss and a 2.38-fold (95% confidence interval, 2.26 to 2.49) increased risk of mortality. We observed similar results for AD. We conclude that older KT recipients have a high risk of post-KT dementia and AD, and these sequelae associate with a profound effect on patient and graft survival.