Incidence, Risk Factors, and Sequelae of Post-kidney Transplant Delirium

Perioperative Considerations in Older Kidney and Liver Transplant Recipients: A Review

With the growth of the older adult population, the number of older adults waitlisted for and undergoing kidney and liver transplantation has increased. Transplantation is an important and definitive treatment for this population. We present a contemporary review of the unique preoperative, intraoperative, and postoperative issues that patients older than 65 y face when they undergo kidney or liver transplantation. We focus on geriatric syndromes that are common in older patients listed for kidney or liver transplantation including frailty, sarcopenia, and cognitive dysfunction; discuss important considerations for older transplant recipients, which may impact preoperative risk stratification; and describe unique challenges in intraoperative and postoperative management for older patients. Intraoperative challenges in the older adult include using evidence-based best anesthetic practices, maintaining adequate perfusion pressure, and using minimally invasive surgical techniques. Postoperative concerns include controlling acute postoperative pain; preventing cardiovascular complications and delirium; optimizing immunosuppression; preventing perioperative kidney injury; and avoiding nephrotoxicity and rehabilitation. Future studies are needed throughout the perioperative period to identify interventions that will improve patients' preoperative physiologic status, prevent postoperative medical complications, and improve medical and patient-centered outcomes in this vulnerable patient population.

Frailty in the context of kidney transplantation

Frailty, defined as an inappropriate response to stressful situations due to the loss of physiological reserve, was initially described in the elderly population, but is currently being identified in younger populations with chronic diseases, such as chronic kidney disease. It is estimated that about 20% of patients are frail at the time of kidney transplantation (KT), and there is great interest in its potential predictive value for unfavorable outcomes. A significant body of evidence has been generated; however, several areas still remain to be further explored. The pathogenesis is poorly understood and limited to the extrapolation of findings from other populations. Most studies are observational, involving patients on the waiting list or post-KT, and there is a scarcity of data on long-term evolution and possible interventions. We reviewed studies, including those with Brazilian populations, assessing frailty in the pre- and post-KT phases, exploring pathophysiology, associated factors, diagnostic challenges, and associated outcomes, in an attempt to provide a basis for future interventions.

Patient Perspectives on the Use of Aging Metrics for Kidney Transplant Decision-Making

INTRODUCTION

Frailty and cognitive function are often measured during kidney transplant evaluation. However, patient perspectives on the ethical considerations of this practice are unclear.

RESEARCH QUESTION

What are patient perspectives on the use of aging metrics in kidney transplant decision-making?

DESIGN

One hundred participants who were evaluated for kidney transplantation and were enrolled in an ongoing prospective cohort study (response rate = 61.3%) were surveyed. Participants were informed of the definitions of frailty and cognitive impairment and then asked survey questions regarding the use of these measures of aging to determine kidney transplant candidacy.

RESULTS

Participants (75.6%) thought it was unfair to prevent older adults from receiving a kidney transplant based on age, but there was less agreement on whether it was fair to deny frail (46.5%) and cognitively impaired (45.9%) patients from accessing kidney transplantation. Compared to older participants, younger participants had 5.36-times (95%CI:1.94-14.81) the odds of choosing a hypothetical younger, frail patient to list for kidney transplantation than an older, non-frail patient; they also had 3.56-times (95%CI:1.33-9.56) the odds of choosing the hypothetical frail patient with social support rather than a non-frail patient without social support. Participants disagreed on the use of patient age as a listing criterion; 19.5% ranked it as the fairest and 28.7% as the least fair.

CONCLUSION

The patient views highlighted in this study are an important step toward developing ethical guidelines to ensure fair use of frailty, cognitive function, and chronological age for kidney transplant decision-making.

Frailty in Kidney Disease: A Comprehensive Review to Advance Its Clinical and Research Applications

Frailty is a multisystem syndrome of decreased physiologic reserve that has been shown to strongly and independently predict morbidity and mortality. Frailty is prevalent in patients living with kidney disease and occurs earlier in individuals with kidney disease as compared to the general population. In this comprehensive review, we examine clinical and research applications of frailty in kidney disease populations. Specifically, we clarify the definition of frailty and address common misconceptions, review the mechanisms and epidemiology of frailty in kidney disease, discuss challenges and limitations in frailty measurement, and provide updated evidence related to risk factors for frailty, its associated adverse outcomes, and interventions. We further add to the literature in this topic by highlighting the potential applications of frailty measurement in the care of patients with kidney disease and conclude with our recommendations for future research related to this important syndrome.

Association between modified frailty index and postoperative delirium in patients after cardiac surgery: A cohort study of 2080 older adults

AIM

To evaluate the association between frailty and postoperative delirium (POD) in elderly cardiac surgery patients.

METHODS

A retrospective study was conducted of older patients admitted to the intensive care unit after cardiac surgery at a tertiary academic medical center in Boston from 2008 to 2019. Frailty was measured using the Modified Frailty Index (MFI), which categorized patients into frail (MFI ≥3) and non-frail (MFI = 0-2) groups. Delirium was identified using the confusion assessment method for the intensive care unit and nursing notes. Logistic regression models were used to examine the association between frailty and POD, and odds ratios (OR) with 95% confidence intervals (CI) were calculated.

RESULTS

Of the 2080 patients included (median age approximately 74 years, 30.9% female), 614 were frail and 1466 were non-frail. The incidence of delirium was significantly higher in the frail group (29.2% vs. 16.4%, p < 0.05). After adjustment for age, sex, race, marital status, Acute Physiology Score III (APSIII), sequential organ failure assessment (SOFA), albumin, creatinine, hemoglobin, white blood cell count, type of surgery, alcohol use, smoking, cerebrovascular disease, use of benzodiazepines, and mechanical ventilation, multivariate logistic regression indicated a significantly increased risk of delirium in frail patients (adjusted OR: 1.61, 95% CI: 1.23-2.10, p < 0.001, E-value: 1.85).

CONCLUSIONS

Frailty is an independent risk factor for POD in older patients after cardiac surgery. Further research should focus on frailty assessment and tailored interventions to improve outcomes.

Age Is Just a Number for Older Kidney Transplant Patients

The rise in the mean age of the global population has led to an increase in older kidney transplant (KT) patients. This demographic shift, coupled with the ongoing organ shortage, requires a nuanced understanding of which older adults are most suitable for KT. Recognizing the increased heterogeneity among older adults and the limitations of solely relying on chronological age, there is a need to explore alternative aging metrics beyond chronological age. In this review, we discuss the impact of older age on access to KT and postoperative outcomes. Emphasizing the need for a comprehensive evaluation that extends beyond chronological age, we explore alternative aging metrics such as frailty, sarcopenia, and cognitive function, underscoring their potential role in enhancing the KT evaluation process. Most importantly, we aim to contribute to the ongoing discourse, fostering an optimized approach to KT for the rapidly growing population of older adults.

Latest advances in frailty in kidney transplantation: A narrative review

Frailty is a clinical syndrome that is characterised by decline in multiple systems with associated decreased physiological reserve and ability to respond to stressor events. It is associated with greater healthcare burden. It is common in patients with end-stage renal disease (ESRD). Kidney transplantation is considered the optimal form of renal replacement therapy for suitable patients with ESRD. However, surgery and immunosuppression are physiological stresses that can disproportionately affect frail individuals. Frailty is emerging as a potentially important risk factor in patients waitlisted for kidney transplantation. Most of the published research to date in this area comes from a single transplant centre in the USA. Frailty, as measured using the Physical Frailty Phenotype (FP), is prevalent in waitlisted patients and has been associated with early hospital re-admission, prolonged length of stay, delayed graft function and increased mortality after kidney transplantation. However, although kidney transplantation is a substantial physiological stress to a patient's reserve, by restoring kidney function, kidney transplantation has also been shown to improve a patient's frailty status. The FP is the most studied tool in patients waitlisted for transplantation, but it has not been able to distinguish those whose frailty is improved by kidney transplantation. In summary, there remain significant gaps in knowledge and uncertainties as to how to effectively use existing frailty measures to inform decision-making around kidney transplantation. Further research is needed to address these important gaps in the literature.

Preoperative Intrathecal Morphine is Associated With Reduced Postoperative Pain, Agitation, and Delirium In Living Donor Kidney Transplantation Recipients

BACKGROUND

Postoperative delirium after organ transplantation can lead to increased length of hospital stay and mortality. Because pain is an important risk factor for delirium, perioperative analgesia with intrathecal morphine (ITM) may mitigate postoperative delirium development. We evaluated if ITM reduces postoperative delirium incidence in living donor kidney transplant (LDKT) recipients.

METHODS

Two hundred ninety-six patients who received LDKT between 2014 and 2018 at our hospital were retrospectively analyzed. Recipients who received preoperative ITM (ITM group) were compared with those who did not (control group). The primary outcome was postoperative delirium based on the Confusion Assessment Method for Intensive Care Unit results during the first 4 postoperative days.

RESULTS

Delirium occurred in 2.6% (4/154) and 7.0% (10/142) of the ITM and control groups, respectively. Multivariable analysis showed age (odds ratio [OR]: 1.07, 95% CI: 1.01-1.14; P = .031), recent smoking (OR: 7.87, 95% CI: 1.43-43.31; P = .018), preoperative psychotropics (OR: 23.01, 95% CI: 3.22-164.66; P = .002) were risk factors, whereas ITM was a protective factor (OR: 0.23, 95% CI: 0.06-0.89; P = .033).

CONCLUSIONS

Preoperative ITM showed an independent association with reduced post-LDKT delirium. Further studies and the development of regional analgesia for delirium prevention may enhance the postoperative recovery of transplant recipients.

Association of Postoperative Delirium With Incident Dementia and Graft Outcomes Among Kidney Transplant Recipients

BACKGROUND

Kidney transplant (KT) recipients have numerous risk factors for delirium, including those shared with the general surgical population (eg, age and major surgery) and transplant-specific factors (eg, neurotoxic immunosuppression medications). Evidence has linked delirium to long-term dementia risk in older adults undergoing major surgery. We sought to characterize dementia risk associated with post-KT delirium.

METHODS

Using the United States Renal Data System datasets, we identified 35 800 adult first-time KT recipients ≥55 y. We evaluated risk factors for delirium using logistic regression. We evaluated the association between delirium and incident dementia (overall and by subtype: Alzheimer's, vascular, and other/mixed-type), graft loss, and death using Fine and Gray's subhazards models and Cox regression.

RESULTS

During the KT hospitalization, 0.9% of recipients were diagnosed with delirium. Delirium risk factors included age (OR = 1.40, 95% CI, 1.28-1.52) and diabetes (OR = 1.38, 95% CI, 1.10-1.73). Delirium was associated with higher risk of death-censored graft loss (aHR = 1.52, 95% CI, 1.12-2.05) and all-cause mortality (aHR = 1.53, 95% CI, 1.25-1.89) at 5 y post-KT. Delirium was also associated with higher risk of dementia (adjusted subhazard ratio [aSHR] = 4.59, 95% CI, 3.48-6.06), particularly vascular dementia (aSHR = 2.51, 95% CI, 1.01-6.25) and other/mixed-type dementia (aSHR = 5.58, 95% CI, 4.24-7.62) subtypes. The risk of all-type dementia associated with delirium was higher for younger recipients aged between 55 and 64 y ( Pinteraction  = 0.01).

CONCLUSIONS

Delirium is a strong risk factor for subsequent diagnosis of dementia among KT recipients, particularly those aged between 55 and 64 y at the time of transplant. Patients experiencing posttransplant delirium might benefit from early interventions to enhance cognitive health and surveillance for cognitive impairment to enable early referral for dementia care.

Considerations regarding anesthesia for renal transplantation

Renal transplantation is a complex surgical procedure requiring meticulous anesthetic planning to ensure patient safety and optimal graft function. In this comprehensive review, we examined various aspects of anesthesia management during renal transplantation, including preoperative, intraoperative, and postoperative care. Preoperative optimization involves the identification and management of risks to mitigate perioperative complications. Treatment with erythropoiesis-stimulating agents is recommended to correct anemia in transplant recipients with hemoglobin levels below 9-10 g/dl. Intraoperative management focuses on hemodynamic monitoring, maintenance of intravascular volume, and careful selection of anesthetic techniques. Neuromuscular monitoring and the appropriate use of neuromuscular blocking and reversal agents are considered essential. Further, hemodynamic goals include maintaining the mean arterial pressure within the range of 80-110 mmHg. In addition, attention should be paid to perioperative glycemic control, temperature management, and diuretic use. In postoperative management, multimodal analgesia and the prevention of postoperative delirium contribute to optimal recovery. The implementation of enhanced recovery after surgery principles can further improve outcomes. Collaborative efforts among surgical teams, anesthesiologists, and healthcare professionals are crucial for achieving successful renal transplantation outcomes.

Impact of Obesity on Kidney Transplant Outcomes in Older Adults

BACKGROUND

The prevalence of obesity in older patients undergoing kidney transplantation is increasing. Older age and obesity are associated with higher risks of complications and mortality post-transplantation. The optimal management of this group of patients remains undefined.

METHODS

We retrospectively analyzed the United Network for Organ Sharing database of adults ≥70 years of age undergoing primary kidney transplant from January 1, 2014, to December 31, 2022. We examined patient and graft survival stratified by body mass index (BMI) in 3 categories, <30 kg/m2, 30 to 35 kg/m2, and >35 kg/m2. We also analyzed other risk factors that impacted survival.

RESULTS

A total of 14,786 patients ≥70 years underwent kidney transplantation. Of those, 9,731 patients had a BMI <30 kg/m2, 3,726 patients with a BMI of 30 to 35 kg/m2, and 1,036 patients with a BMI >35 kg/m2. During the study period, there was a significant increase in kidney transplants in patients ≥70 years old across all BMI groups. Overall, patient survival, death-censored graft survival, and all-cause graft survival were lower in obese patients compared with nonobese patients. Multivariable analysis showed worse patient survival and graft survival in patients with a BMI of 30 to 35 kg/m2, a BMI >35 kg/m2, a longer duration of dialysis, diabetes mellitus, and poor functional status.

CONCLUSION

Adults ≥70 years should be considered for kidney transplantation. Obesity with a BMI of 30 to 35 kg/m2 or >35 kg/m2, longer duration of dialysis, diabetes, and functional status are associated with worse outcomes. Optimization of these risk factors is essential when considering these patients for transplantation.

Frailty and Kidney Transplant Waitlisting: A Single-Center Experience

BACKGROUND

Frailty is widely prevalent among kidney transplant (KT) candidates and is associated with poor peri and post-transplant outcomes. Whether frailty is a modifiable risk factor in KT candidates is unknown. Efforts to intervene in frailty have been hindered by a lack of a standardized approach to testing and treating frailty in clinical practice.

METHODS

Patients undergoing evaluation for kidney transplantation underwent frailty testing during their clinical visits using a combination of the Short Physical Performance Battery (SPPB) and Groningen Frailty Indicator (GFI) instruments. Scores from the SPPB and GFI were combined to stratify patients into 4 risk groups. Patients in the highest-risk groups were referred to physical therapy (PT) and returned for repeat frailty testing. Pre- and post-PT scores were compared with assessment for improvement.

RESULTS

Forty patients met the criteria for PT, of which 16 (40%) completed PT and returned for repeat frailty testing. The mean SPPB score improved from 5.88 to 8.94 after PT (P < .01). The mean GFI score improved from 5.25 to 4.06 after PT but was not statistically significant (P = .081).

CONCLUSIONS

Our unique approach of using 2 validated scores, SPPB and GFI, together addressed many components of frailty evaluation, including physical, cognitive, and psychosocial components. We used PT as a targeted intervention for addressing both the physical and non-physical impairments among frail KT candidates. Physical therapy was noted to have a positive impact on each of these components.

Development and Validation of an Abridged Physical Frailty Phenotype for Clinical Use: A Cohort Study Among Kidney Transplant Candidates

BACKGROUND

Frailty is associated with poor outcomes in surgical patients including kidney transplant (KT) recipients. Transplant centers that measure frailty have better pre- and postoperative outcomes. However, clinical utility of existing tools is low due to time constraints. To address this major barrier to implementation in the preoperative evaluation of patients, we developed an abridged frailty phenotype.

METHODS

The abridged frailty phenotype was developed by simplifying the 5 physical frailty phenotype (PFP) components in a two-center prospective cohort of 3 220 KT candidates and tested for efficiency (time to completion) in 20 candidates evaluation (January 2009 to March 2020). We examined area under curve (AUC) and Cohen's kappa agreement to compare the abridged assessment with the PFP. We compared waitlist mortality risk (competing risks models) by frailty using the PFP and abridged assessment, respectively. Model discrimination was assessed using Harrell's C-statistic.

RESULTS

Of 3 220 candidates, the PFP and abridged assessment identified 23.8% and 27.4% candidates as frail, respectively. The abridged frailty phenotype had substantial agreement (kappa = 0.69, 95% CI: 0.66-0.71) and excellent discrimination (AUC = 0.861). Among 20 patients at evaluation, abridged assessment took 5-7 minutes to complete. The PFP and abridged assessment had similar associations with waitlist mortality (subdistribution hazard ratio [SHR] = 1.62, 95% CI: 1.26-2.08 vs SHR = 1.70, 95% CI: 1.33-2.16) and comparable mortality discrimination (p = .51).

CONCLUSIONS

The abridged assessment is an efficient and valid way to identify frailty. It predicts waitlist mortality without sacrificing discrimination. Surgical departments should consider utilizing the abridged assessment to evaluate frailty in patients when time is limited.

Importance of Frailty in Kidney Transplant Recipients

BACKGROUND

Frailty is a persistent chronic inflammatory syndrome present in many patients with chronic kidney disease. After kidney transplant (KT), it has been associated with complications such as delayed graft function, hospital readmission, or poorer KT survival.

PURPOSE

To assess the impact of frailty on the results of KT.

METHODS

Longitudinal prospective study of 65 patients included on the waiting list (WL) between October 2019 and October 2021. We used the FRAIL scale and recorded clinical characteristics, including demographic, dependency scales, and analytical parameters at the moment of the inclusion on the WL and at months 3 and 12 after KT.

RESULTS

The mean age was 58 years old, and 70% of KT were men. The comorbidity burden was 26% diabetes, 83% hypertension, and 12% ischemic heart disease. Forty patients (61.5%) presented ≥1 point on the FRAIL scale, and 25 (38.4%) were robust. Frail patients (FRAIL score≥3) had a higher Charlson comorbidity index at the time of KT, a lower Barthel index, and a lower quality of life measured by KDQOL-36. No significant differences were observed in other variables, such as days of admission, surgical complications, or delayed graft function. There were 3 graft losses censored for death and 4 deaths, all in frail or prefrail patients. These patients had lower graft survival (P = .164) and patient survival (P = .096). At 12 months post KT, frailty improved in 67% of patients evaluated.

CONCLUSION

Frailty is a common condition among patients on the WL, leading to poorer quality of life, greater dependency, and a higher risk of graft loss and mortality. Frailty conditions can be reversed in many patients after KT.

Putting Guidelines Into Practice: Is Frailty Measurement at the Time of Kidney Transplant Eligibility Assessment Valid, Feasible, and Acceptable to Patients?

Background

Clinical Practice Guidelines suggest that frailty be measured during kidney transplant eligibility assessments. Yet it is not known how frailty is best assessed in this setting or whether its assessment is acceptable to patients. We aimed to examine the construct validity and feasibility of Frailty Index (FI) assessment among patients attending a kidney transplant assessment clinic and to explore patients' perspectives on frailty and the acceptability of its routine assessment.

Methods

A 58-item FI was calculated for 147 clinic patients. Semistructured interviews were conducted with a subgroup of 29 patients. The FI was validated against normative FI characteristics (mean, distribution, limit), age, and the Estimated Post-Transplant Survival Score. Feasibility was assessed using descriptive statistics. Qualitative data were analyzed using reflexive thematic analysis.

Results

The mean FI was 0.23 (±0.10, normal distribution, limit 0.53). FI increased with age and Estimated Post-Transplant Survival score. The FI was completed for 62.8% of eligible patients (147/234). The median completion time was 10 min, and completion rate (with no missing data) was 100%. Four themes were identified: perceptions of frailty, acceptability, perceived benefits, and risks of frailty measurement. Patients linked frailty with age and adverse outcomes, and most did not consider themselves frail. Patients reported that the FI was quick, simple, and efficient. They felt that frailty assessment is relevant to transplant eligibility and should be used to address potentially reversible factors.

Conclusions

The FI demonstrated construct validity and was feasible and acceptable in this clinic setting. The challenge is ensuring that routine assessments lead to better care.

Old Age and Frailty in Deceased Organ Transplantation and Allocation-A Plea for Geriatric Assessment and Prehabilitation

Due to demographic ageing and medical progress, the number and proportion of older organ donors and recipients is increasing. At the same time, the medical and ethical significance of ageing and old age for organ transplantation needs clarification. Advanced age is associated with the frailty syndrome that has a negative impact on the success of organ transplantation. However, there is emerging evidence that frailty can be modified by suitable prehabilitation measures. Against this backdrop, we argue that decision making about access to the transplant waiting list and the allocation of donor organs should integrate geriatric expertise in order to assess and manage frailty and impairments in functional capacity. Prehabilitation should be implemented as a new strategy for pre-operative conditioning of older risk patients' functional capacity. From an ethical point of view, advanced chronological age per se should not preclude the indication for organ transplantation and the allocation of donor organs.

Cellular Senescence and Frailty in Transplantation

Purpose of review

To summarizes the literature on cellular senescence and frailty in solid-organ transplantation and highlight the emerging role of senotherapeutics as a treatment for cellular senescence.

Recent findings

Solid-organ transplant patients are aging. Many factors contribute to aging acceleration in this population, including cellular senescence. Senescent cells accumulate in tissues and secrete proinflammatory and profibrotic proteins which result in tissue damage. Cellular senescence contributes to age-related diseases and frailty. Our understanding of the role cellular senescence plays in transplant-specific complications such as allograft immunogenicity and infections is expanding. Promising treatments, including senolytics, senomorphics, cell-based regenerative therapies, and behavioral interventions, may reduce cellular senescence abundance and frailty in patients with solid-organ transplants.

Summary

Cellular senescence and frailty contribute to adverse outcomes in solid-organ transplantation. Continued pursuit of understanding the role cellular senescence plays in transplantation may lead to improved senotherapeutic approaches and better graft and patient outcomes.

Frailty assessment as part of transplant listing: yes, no or maybe?

Frailty, characterized by a decreased physiological reserve and an increased vulnerability to stressors, is common among kidney transplant (KT) candidates and recipients. In this review, we present and summarize the key arguments for and against the assessment of frailty as part of KT evaluation. The key arguments for including frailty were: (i) sheer prevalence and far-reaching consequences of frailty on KT, and (ii) the ability to conduct a more holistic and objective evaluation of candidates, removing the inaccuracy associated with 'eye-ball' assessments of transplant fitness. The key argument against were: (i) lack of agreement on the definition of frailty and which tools should be used in renal populations, (ii) a lack of clarity on how, by whom and how often frailty assessments should be performed, and (iii) a poor understanding of how acute stressors affect frailty. However, it is the overwhelming opinion that the time has come for frailty assessments to be incorporated into KT listing. Although ongoing areas of uncertainty exist and further evidence development is needed, the well-established impact of frailty on clinical and experiential outcomes, the invaluable information obtained from frailty assessments, and the potential for intervention outweigh these limitations. Proactive and early identification of frailty allows for individualized and improved risk assessment, communication and optimization of candidates.

Frailty and Age-Associated Assessments Associated with Chronic Kidney Disease and Transplantation Outcomes

Background. Frailty is often defined as a decrease in physiological reserve and has been shown to be correlated with adverse health outcomes and mortality in the general population. This condition is highly prevalent in the chronic kidney disease (CKD) patient population as well as in kidney transplant (KT) recipients. Other age-associated changes include sarcopenia, nutrition, cognition, and depression. In assessing the contributions of these components to patient outcomes and their prevalence in the CKD and KT patient population, it can be determined how such variables may be associated with frailty and the extent to which they may impact the adverse outcomes an individual may experience. Objectives. We sought to perform a systematic literature review to review published data on frailty and associated age-associated syndromes in CKD and KT patients. Results. Over 80 references pertinent to frailty, sarcopenia, nutrition, cognition, or depression in patients with CKD or KT were identified. Systematic review was performed to evaluate the data supporting the use of the following approaches: Fried Frailty, Short Physical Performance Battery, Frailty Index, Sarcopenia Index, CT scan quantification of muscle mass, health-related quality of life, and assessment tools for nutrition, cognition, and depression. Conclusion. This report represents a comprehensive review of previously published research articles on this topic. The intersectionality between all these components in contributing to the patient’s clinical status suggests a need for a multifaceted approach to developing comprehensive care and treatment for the CKD and KT population to improve outcomes before and after transplantation.

Factors associated with frailty in kidney transplant recipients: A cross-sectional study

BACKGROUND

Frailty is prevalent in kidney transplant recipients and associated with multiple health care challenges. The association between frailty and outcomes has been extensively studied in kidney transplant recipients, but the status of frailty and its associated factors are not well studied, hindering efforts to develop strategies to improve care and reduce frailty.

OBJECTIVES

To identify the factors that are associated with frailty in kidney transplant recipients comprehensively.

DESIGN AND PARTICIPANTS

The associated factors of frailty were explored by a cross-sectional study of 185 kidney transplant recipients.

MEASUREMENTS

Data were collected using the general information questionnaire, the Charlson comorbidity index, the Pittsburgh Sleep Quality Index, the Hospital Anxiety and Depression Scale, the Connor-Davidson Resilience Scale, the Perceived Social Support Scale and the Tilburg Frailty Indicator. Data were analyzed using the multiple linear regression analysis.

RESULTS

A total of 75 (40.5%) kidney transplant recipients were assessed as frail by Chinese TFI. Age (β = 0.228), time post-transplant (β = 0.055), sleep quality (β = 0.224) and psychological resilience (β = -0.038) entered the final multiple regression equation and accounted for 41.8% of the total frailty variation (R²  = 0.418, F = 21.31, p < 0.05).

CONCLUSIONS

Frailty was common among kidney transplant recipients. Old age, long time after transplantation, poor sleep quality and low psychological resilience were main associated factors for frailty. Integrated care interventions are therefore needed for this vulnerable population to prevent or delay frailty.

Frailty as a predictor of poor outcomes among patients awaiting liver transplant: a systematic review and meta-analysis

Aim

This review sought to evaluate the significance of a functional assessment for liver transplant candidates, i.e., frailty, in the pre-transplant setting and its association with mortality and morbidities.

Background

Liver transplantation (LT) remains the treatment of choice for patients with end-stage liver disease. Due to the shortage of organs for LT, a careful selection of suitable recipients is essential. Frailty, a measure of physiologic reserve and increased vulnerability to stressors, was initially used in geriatrics and then introduced to the field of transplantation for better patient selection.

Methods

PubMed, Scopus, and Web of Science databases were reviewed up until January 2023. The search terms included: "frail*", "liver", and "transplant*". A Meta-analysis was conducted for the hazard ratios (HRs) obtained from the COX regression models. Fifty-five studies were included in this review; ten were included in the meta-analysis.

Results

The prevalence of frailty varied from 2.82% to 70.09% in the studies. Meta-analysis showed that overall frailty had a significant association with mortality (pooled adjusted HR [95%CI]: 2.66 [1.96-3.63]). Subgroup analyses revealed that both the Liver Frailty Index and Fried Frailty Index were significantly associated with mortality. Furthermore, these studies have demonstrated that this population's frailty is associated with ascites, hepatic encephalopathy, and esophageal varices.

Conclusion

According to emerging evidence, frailty is associated with increased morbidity and mortality of the patients on the LT waiting list. Further randomized trials are required to determine the efficacy and safety of variable interventions in the frail population.

Transitions in frailty state 12 months after kidney transplantation: a prospective cohort study

BACKGROUND

Frailty is associated with several unfavorable outcomes after kidney transplantation (KTx). However, limited information is available regarding the transitions in frailty state and its components after KTx. This study aimed to evaluate the transitions in physical frailty phenotype and its components over a period of 12 months after KTx.

METHODS

In this prospective single-center cohort study, we measured physical frailty phenotype (PFP) and its components at the time of admission for KTx and 12 months after KTx. The evaluation includes five components: weakness (grip strength analysed by sex and body mass index quartiles), physical activity (kcals/week based on the Minnesota Leisure Time Physical Activity questionnaire), exhaustion (self-report using the Center for Epidemiological Studies Depression Scale), gait speed (time taken to walk 15 feet based on sex and height-specific cutoff), and unintentional weight loss (self-report of unintentional weight loss > 10 lbs in the last year). The exhaustion and physical activity components are validated in the Brazilian population. Each component is scored as 0 or 1 according to its presence or absence, and a PFP score of 3-5 defines frailty, 2 is intermediate, and 0-1 is rated as non-frail. We used the McNemar and Wilcoxon test to compare physical frailty phenotype and its components between the two periods.

RESULTS

Among 87 patients included in the study, 16.1% were classified as frail, 20.7% as intermediately frail, and 63.2% as non-frail. Sixty-four patients were included in the analysis to evaluate transitions in frailty. At the time of admission for KTx, 15.6% of patients were defined as frail compared to 4.7% of patients at 12 months after KTx (p = 0.023). Among the physical frailty phenotype components, the proportion of patients who scored in the weight loss category 12 months after KTx was significantly lower than that at the time of KTx (6.3% vs 34.4%, p < 0.001).

CONCLUSIONS

There was a 69.9% reduction in the prevalence of frail patients at the end of the 12-month follow-up after KTx. Among the components of frailty, weight loss showed a significant improvement.

Delirium, changes in cognitive function, and risk of diagnosed dementia after kidney transplantation

Kidney transplant (KT) recipients with delirium, a preventable surgical complication, are likely to reap cognitive benefits from restored kidney function, but may be more vulnerable to longer-term neurotoxic stressors post-KT (i.e., aging, immunosuppression). In this prospective cohort study, we measured delirium (chart-based), global cognitive function (3MS), and executive function (Trail Making Test Part B minus Part A) in 894 recipients (2009-2021) at KT, 1/3/6-months, 1-year, and annually post-KT. Dementia was ascertained using linked Medicare claims. We described repeated measures of cognitive performance (mixed effects model) and quantified dementia risk (Fine & Gray competing risk) by post-KT delirium. Of 894 recipients, 43(4.8%) had post-KT delirium. Delirium was not associated with global cognitive function at KT (difference = -3.2 points, 95%CI: -6.7, 0.4) or trajectories post-KT (0.03 points/month, 95%CI: -0.27, 0.33). Delirium was associated with worse executive function at KT (55.1 s, 95%CI: 25.6, 84.5), greater improvements in executive function <2 years post-KT (-2.73 s/month, 95%CI: -4.46,-0.99), and greater decline in executive function >2 years post-KT (1.72 s/month, 95%CI: 0.22, 3.21). Post-KT delirium was associated with over 7-fold greater risk of dementia post-KT (adjusted subdistribution hazard ratio = 7.84, 95%CI: 1.22, 50.40). Transplant centers should be aware of cognitive risks associated with post-KT delirium and implement available preventative interventions to reduce delirium risk.

Frailty and solid-organ transplant candidates: a scoping review

BACKGROUND

There is currently no consensus as to a standardized tool for frailty measurement in any patient population. In the solid-organ transplantation population, routinely identifying and quantifying frailty in potential transplant candidates would support patients and the multidisciplinary team to make well-informed, individualized, management decisions. The aim of this scoping review was to synthesise the literature regarding frailty measurement in solid-organ transplant (SOT) candidates.

METHODS

A search of four databases (Cochrane, Pubmed, EMBASE and CINAHL) yielded 3124 studies. 101 studies (including heart, kidney, liver, and lung transplant candidate populations) met the inclusion criteria.

RESULTS

We found that studies used a wide range of frailty tools (N = 22), including four 'established' frailty tools. The most commonly used tools were the Fried Frailty Phenotype and the Liver Frailty Index. Frailty prevalence estimates for this middle-aged, predominantly male, population varied between 2.7% and 100%. In the SOT candidate population, frailty was found to be associated with a range of adverse outcomes, with most evidence for increased mortality (including post-transplant and wait-list mortality), post-operative complications and prolonged hospitalisation. There is currently insufficient data to compare the predictive validity of frailty tools in the SOT population.

CONCLUSION

Overall, there is great variability in the approach to frailty measurement in this population. Preferably, a validated frailty measurement tool would be incorporated into SOT eligibility assessments internationally with a view to facilitating comparisons between patient sub-groups and national and international transplant services with the ultimate goal of improved patient care.

Dialysis or kidney transplantation in older adults? A systematic review summarizing functional, psychological, and quality of life-related outcomes after start of kidney replacement therapy

BACKGROUND

In older patients, the choice between kidney transplantation (KT) and dialysis may be complicated because of a high prevalence of comorbidities and geriatric syndromes. Ideally, this decision-making process focusses on older patients' outcome priorities, which frequently include functional, psychological, and quality of life (QOL)-related outcomes.

PURPOSE

This systematic review aims to summarize functional, psychological (including cognition), and QOL-related outcomes after start of kidney replacement therapy (KRT) in older adults.

METHODS

We searched PubMed and Embase for research that investigated change in these variables after start of KRT in patients aged ≥ 60 years. Data were extracted using the summary measures reported in the individual studies. Risk of bias was assessed with the ROBINS-I tool.

RESULTS

Sixteen observational studies (prospective n = 9, retrospective n = 7; KT-recipients n = 3, dialysis patients n = 13) were included. The results show that QOL improves in the majority of the older KT recipients. After start of dialysis, QOL improved or remained stable for most patients, but this seems less prevalent than after KT. Functional status decreases in a substantial part of the older dialysis patients. Furthermore, the incidence of serious fall injuries increases after start of dialysis. Nutritional status seems to improve after start of dialysis.

CONCLUSION

The interpretability and comparability of the included studies are limited by the heterogeneity in study designs and significant risk of bias in most studies. Despite this, our overview of functional, psychological (including cognition), and QOL-related outcomes is useful for older adults and their clinicians facing the decision between KT and dialysis.

Anaesthetic Approach to Enhanced Recovery after Surgery for Kidney Transplantation: A Narrative Review

Enhanced recovery after surgery (ERAS) protocols are designed to reduce medical complications, the length of hospital stays (LoS), and healthcare costs. ERAS is considered safe and effective for kidney transplant (KTx) surgery. KTx recipients are often frail with multiple comorbidities. As these patients follow an extensive diagnostic pathway preoperatively, the ERAS protocol can ideally be implemented at this stage. Small singular changes in a long perioperative pathway can result in significant positive outcomes. We have investigated the current evidence for an ERAS pathway related to anaesthetic considerations in renal transplant surgery for adult recipients.

Kidney transplantation or dialysis in older adults-an interview study on the decision-making process

BACKGROUND

In older patients with end-stage kidney disease (ESKD), the choice between kidney transplantation (KT) and dialysis may be more complex than in younger patients because of a higher prevalence of comorbidities and frailty. This study aims to provide greater insight into the current decision-making process by exploring the expectations, experiences and health outcome priorities of all stakeholders.

METHODS

We performed semi-structured interviews with patients ≥65 years with ESKD (eGFR <15 ml/min/1.73m2, KT recipient or treated with dialysis), patients' relatives and healthcare professionals (nephrologists, nurses and medical social workers). Interviews were conducted until data saturation and thematically analysed.

RESULTS

We performed 36 interviews (patients n = 18, relatives n = 5, healthcare professionals n = 13). Thematic analysis revealed five themes. Older patients' health outcome priorities were mostly related to quality of life (QOL). Individual older patients showed marked differences in the preferred level of engagement during the decision-making process (varying from 'wants to be in the lead' to 'follows the nephrologist') and in informational needs (varying from evidence-based to experience-based). On the contrary, healthcare professionals were quite unanimous on all aspects. They focused on determining eligibility for KT as start of the decision-making process, on clear and extensive information provision and on classical, medical outcomes.

CONCLUSIONS

The decision-making process could benefit from early identification of older patients' values, needs and health outcome priorities, in parallel with assessment of KT eligibility and before discussing the treatment options, and the explicit use of this information in further steps of the decision-making process.

Revision of frailty assessment in kidney transplant recipients: Replacing unintentional weight loss with CT-assessed sarcopenia in the physical frailty phenotype

Kidney transplantation (KT) experts did not support the use of subjective unintentional weight loss to measure shrinking in the physical frailty phenotype (PFP); a clinically feasible and predictive measure of shrinking is needed. To test whether unintentional weight loss could be replaced by an assessment of sarcopenia using existing CT scans, we performed a prospective cohort study of adult KT recipients with original PFP (oPFP) measured at admission (December 2008-February 2020). We ascertained sarcopenia by calculating skeletal muscle index from available, clinically obtained CTs within 1-year pre-KT (male < 50 cm² /m² ; female < 39 cm² /m² ) and combined it with the original four components to determine new PFP (nPFP) scores. Frailty was classified by frailty score: 0: non-frail; 1-2: pre-frail; ≥3: frail. Mortality and graft loss hazard ratios (HRs) were estimated using adjusted Cox proportional hazard models. Model discrimination was quantified using Harrell's C-statistic. Among 1113 recipients, 18.6% and 17.1% were frail by oPFP and nPFP, respectively. Compared to non-frail recipients, frail patients by either PFP had higher risks of mortality (oPFP HR = 1.67, 95% CI: 1.07-2.62, C = 0.710; nPFP HR = 1.68, 95% CI: 1.06-2.66, C = 0.710) and graft loss (oPFP HR = 1.67, 95% CI: 1.17-2.40, C = 0.631; nPFP HR = 1.66, 95% CI: 1.15-2.40, C = 0.634) with similar discriminations. oPFP and nPFP are equally useful in risk prediction for KT recipients; oPFP may aid in screening patients for pre-KT interventions, while nPFP may assist in nuanced clinical decision-making.

Long-Term Trajectories of Frailty and Its Components After Kidney Transplantation

BACKGROUND

Frailty is common and associated with poor outcomes among kidney transplant (KT) recipients. While frailty improves in the first 3 months post-KT with restored kidney function, longer-term trajectories are likely to plateau/decline due to aging and other stressors (eg, immunosuppression). We evaluated longer-term post-KT trajectories of the physical frailty phenotype (PFP) and its components in adult patients at 2 centers.

METHODS

PFP components were measured at admission, 1, 3, 6 months, 1 year, and annually thereafter post-KT. We used adjusted mixed-effects models to describe repeated measures of continuous components (weight, gait speed, grip strength, activity) and generalized estimating equations to quantify longitudinal, binomial response patterns (PFP; exhaustion).

RESULTS

Among 1 336 recipients (mean age = 53) followed for a median of 1.9 years (interquartile range [IQR] = 0.1-3.2), likelihood of frailty declined in the first 2.5 years post-KT (adjusted odds ratio [aOR] = 0.96, 95% confidence interval [CI]: 0.95, 0.98), but increased after 2.5 years post-KT (aOR = 1.03, 95% CI: 1.00, 1.05). In the first 2.5 years post-KT, recipients demonstrated increases in weight (0.4 lbs/month, 95% CI: 0.3, 0.5), grip strength (0.2 kg/month, 95% CI: 0.1, 0.2), and activity (23.9 kcal/month, 95% CI: 17.5, 30.2); gait speed remained stable (-0.01 s/month, 95% CI: 0.01, 0.003). Additionally, likelihood of becoming exhausted declined post-KT (OR = 0.99, 95% CI: 0.98, 1.00). After 2.5 years post-KT, recipients demonstrated decreased grip strength (-0.07 kg/month, 95% CI: -0.12, -0.01) and activity (-20 kcal/month, 95% CI: -32.3, -8.2); they had stable weight (-0.003 lbs/month, 95% CI: -0.17, 0.16), gait speed (-0.003 s/month, 95% CI: -0.02, 0.01), and likelihood of becoming exhausted (OR = 1.01, 95% CI: 0.99, 1.02).

CONCLUSION

Despite frailty improvements in the first 2.5 years, recipients' frailty worsened after 2.5 years post-KT. Specifically, they experienced gains in strength, activity, and exhaustion in the first 2.5 years post-KT, but declined in strength and activity after 2.5 years post-KT while experiencing persistent slowness. Clinicians should consider monitoring recipients for worsening frailty after 2.5 years despite shorter-term improvements.

Transplant centers that assess frailty as part of clinical practice have better outcomes

BACKGROUND

Frailty predicts adverse post-kidney transplant (KT) outcomes, yet the impact of frailty assessment on center-level outcomes remains unclear. We sought to test whether transplant centers assessing frailty as part of clinical practice have better pre- and post-KT outcomes in all adult patients (≥18 years) and older patients (≥65 years).

METHODS

In a survey of US transplant centers (11/2017-4/2018), 132 (response rate = 65.3%) centers reported their frailty assessment practices (frequency and specific tool) at KT evaluation and admission. Assessment frequency was categorized as never, sometime, and always; type of assessment tool was categorized as none, validated (for post-KT risk prediction), and any other tool. Center characteristics and clinical outcomes for adult patients during 2017-2019 were gleaned from the transplant national registry (Scientific Registry of Transplant Recipients). Poisson regression was used to estimate incidence rate ratios (IRRs) of waitlist outcomes (waitlist mortality, transplantation) in candidates and IRRs of post-KT outcomes (all-cause mortality, death-censored graft loss) in recipients by frailty assessment frequency. We also estimated IRRs of waitlist outcomes by type of assessment tool at evaluation. All models were adjusted for case mix and center characteristics.

RESULTS

Assessing frailty at evaluation was associated with lower waitlist mortality rate (always IRR = 0.91,95%CI:0.84-0.99; sometimes = 0.89,95%CI:0.83-0.96) and KT rate (always = 0.94,95%CI:0.91-0.97; sometimes = 0.88,95%CI:0.85-0.90); the associations with waitlist mortality rate (always = 0.86,95%CI:0.74-0.99; sometimes = 0.83,95%CI:0.73-0.94) and KT rate (always = 0.82,95%CI:0.77-0.88; sometimes = 0.92,95%CI:0.87-0.98) were stronger in older patients. Furthermore, using validated (IRR = 0.90,95%CI:0.88-0.92) or any other tool (IRR = 0.90,95%CI:0.87-0.93) at evaluation was associated lower KT rate, while only using a validated tool was associated with lower waitlist mortality rate (IRR = 0.89,95%CI:0.83-0.96), especially in older patients (IRR = 0.82,95%CI:0.72-0.93). At admission for KT, always assessing frailty was associated with a lower graft loss rate (IRR = 0.71,95%CI:0.54-0.92) but not with mortality (IRR = 0.93,95%CI:0.76-1.13).

CONCLUSIONS

Assessing frailty at evaluation is associated with lower KT rate, while only using a validated frailty assessment tool is associated with better survival, particularly in older candidates. Centers always assessing frailty at admission are likely to have better graft survival rates. Transplant centers may utilize validated frailty assessment tools to secure KT access for appropriate candidates and to better allocate health care resources for patients identified as frail, particularly for older patients.

Low muscle mass and early hospital readmission post-kidney transplantation

PURPOSE

Patients exhibiting features of frailty and sarcopenia increasingly are presenting for kidney transplantation (KT) assessment. Sarcopenia, when ascertained by radiological measures, is associated with a higher transplant waiting list mortality; but studies on post-operative outcomes are lacking. We aimed to determine the clinical significance of low muscle mass in chronic kidney disease (CKD) patients subsequently receiving KT.

METHODS

We retrospectively analyzed 63 patients with Stage 4-5 CKD who, between 2012 and 2020, had undergone abdominal computed tomography (CT) scanning up to 2 years before KT. The degree of skeletal muscle loss was assessed using the total cross-sectional skeletal muscle area at the third lumbar vertebral level (L3). Cox proportional-hazards regression and Frailty models were used to identify risk factors for early hospital readmission post KT.

RESULTS

Thirty-four patients (54%) displayed low muscle mass, which was independently associated with a lower serum creatinine and phosphate, lower body mass index, lower mean muscle attenuation of the L3 cross-sectional area, and higher serum parathyroid hormone (for all p < 0.05). Deceased donor transplant recipients (n = 45) with low muscle mass demonstrated greater hospital readmissions within 30 days of KT [adjusted hazard ratio (HR) = 4.24, 95% CI 1.40-12.90, p = 0.01].

CONCLUSION

Low muscle mass is highly prevalent in the pre-transplant CKD population and is associated with increased hospital readmission in the early post-transplant period.

Association between frailty and postoperative delirium: a meta-analysis of cohort study

BACKGROUND

Frailty has been suggested as a possible risk factor for postoperative delirium (POD). However, results of previous studies were not consistent. We performed a meta-analysis of cohort study to evaluate the above association.

METHODS

Relevant studies were obtained via systematic search of PubMed, Embase, SCOPUS, and Web of Science databases. Only studies with multivariate analysis were included. A random-effect model incorporating the potential heterogeneity was used to combine the results.

RESULTS

Fifteen cohort studies including 3250 adult patients who underwent surgery were included, and the prevalence of frailty was 27.1% (880/3250) before surgeries. Overall, POD occurred in 513 patients (15.8%). Pooled results showed that frailty was associated with a higher risk of POD (adjusted odds ratio [OR]: 3.23, 95% confidence interval [CI]: 2.56-4.07, P < 0.001) without significant heterogeneity (P for Cochrane's Q test = 0.25, I² = 18%). Subgroup analyses showed a more remarkable association between frailty and POD in prospective cohort studies (OR: 3.64, 95% CI: 2.95-4.49, P < 0.001) than that in retrospective cohort studies (OR: 2.32, 95% CI: 1.60-3.35, P < 0.001; P for subgroup difference = 0.04). Moreover, the association was not affected by country of the study, age group of the patient, elective or emergency surgeries, cardiac and non-cardiac surgeries, evaluation instruments for frailty, diagnostic methods for POD, or quality score of the study (P for subgroup difference all > 0.05).

CONCLUSIONS

Frailty may be associated with a higher risk of POD in adult population.

The clinical application of frailty in nephrology and transplantation

PURPOSE OF REVIEW

Clinicians treating end-stage kidney disease (ESKD) and kidney transplant patients face unique challenges in their care because of the high burden of frailty in these patients. Frailty has gained significant attention by medical and surgical specialties for risk stratification in the past decades. This review highlights the importance of measuring frailty in kidney transplant candidates and recipients.

RECENT FINDINGS

Emerging data support that frailty is present even at younger ages among patients undergoing dialysis, transplant evaluation, or transplantation. It is estimated that 18.8% of younger (18-64 years) candidates, 25.2% of older (≥65 years) candidates, 14.3% of younger recipients, and 20.8% of older recipients are frail. Additionally, frailty is dynamic and subject to change pretransplantation and posttransplantation. Although many patients and clinicians are aware of the importance of measuring frailty, further studies addressing the need for interventions to reduce frailty burden are needed.

SUMMARY

Frailty is independently associated with many adverse outcomes in ESKD and kidney transplant populations. Given the growing number of ESKD and kidney transplant patients, it is pivotal to expand the utility of frailty measurement in clinical practice, recognize the burden of frailty, and identify appropriate interventions to mitigate the adverse effects of frailty.

The Association Between Preoperative Frailty and Postoperative Delirium: A Systematic Review and Meta-analysis

PURPOSE

Identifying factors that place patients at high risk for developing postoperative delirium is an important first step to reduce incidence. Frailty is associated with poor postoperative outcomes. This meta-analysis aims to determine the association between preoperative frailty and postoperative delirium.

DESIGN

This is a systematic review and meta-analysis.

METHODS

We used PubMed, Scopus, Embase, CINAHL, Cochrane, and Web of Science as databases for the search up to April 23, 2020. We included cohort studies that assessed postoperative delirium as the outcome and described the prevalence of delirium among participants during the postoperative period. Odds ratio and 95% confidence interval were calculated to examine the association.

FINDINGS

Twenty cohort studies met our inclusion criteria, which included a total of 4,568 patients. We found that preoperative frailty was significantly associated with an increased risk of postoperative delirium (crude odds ratio: 3.28; 95% confidence interval: 2.51 to 4.28; I² = 46.7%) (adjusted odds ratio: 2.45; 95% confidence interval: 1.58 to 3.81; I² = 88.6%).

CONCLUSIONS

This meta-analysis showed that preoperative frailty is an independent risk factor for postoperative delirium. In patients undergoing cardiovascular surgery, there is a lower association between frailty and postoperative delirium. In patients with other types of surgery, preoperative frailty is closely related to postoperative delirium.

Sarcopenia and Frailty: Challenges in Mainstream Nephrology Practice

Sarcopenia and frailty are prevalent in the chronic kidney disease (CKD) population. Sarcopenia is characterised by the loss of muscle mass and function, while frailty is defined as a multi-system impairment associated with increased vulnerability to stressors. There is substantial overlap between the 2 conditions, particularly with regards to physical aspects: low grip strength, gait speed and low muscle mass. Both sarcopenia and frailty have been associated with a wide range of adverse health outcomes. Although there is no recommended pharmacological treatment as yet, it is widely accepted that exercise training and nutritional supplementation are the key interventions to maintain skeletal muscle mass and strength. This review aims to present a comprehensive overview of sarcopenia and frailty in patients with CKD.

Cognitive impairment burden in older and younger adults across the kidney transplant care continuum

BACKGROUND

Younger kidney transplant (KT) candidates and recipients may have cognitive impairment due to chronic diseases and reliance on dialysis.

METHODS

To quantify cognitive impairment burden by age across the KT care continuum, we leveraged a two-center cohort study of 3854 KT candidates at evaluation, 1114 recipients at admission, and 405 recipients at 1-year post-KT with measured global cognitive performance (3MS) or executive function (Trail Making Test). We also estimated burden of severe cognitive impairment that affects functional dependence (activities of daily living [ADL] < 6 or instrumental activities of daily living [IADL] < 8).

RESULTS

Among KT candidates, global cognitive impairment (18-34 years: 11.1%; 35-49 years: 14.0%; 50-64 years: 19.5%; ≥65 years: 22.0%) and severe cognitive impairment burden (18-34 years: 1.1%; 35-49 years: 3.0%; 50-64 years: 6.2%; ≥65 years: 7.7%) increased linearly with age. Among KT recipients at admission, global cognitive impairment (18-34 years: 9.1%; 35-49 years: 6.1%; 50-64 years: 9.3%; ≥65 years: 15.7%) and severe cognitive impairment burden (18-34 years: 1.4%; 35-49 years: 1.4%; 50-64 years: 2.2%; ≥65 years: 4.6%) was lower. Despite lowest burden of cognitive impairment among KT recipients at 1-year post-KT across all ages (18-34 years: 1.7%; 35-49 years: 3.4%; 50-64 years: 4.3%; ≥65 years: 6.5%), many still exhibited severe cognitive impairment (18-34 years: .0%; 35-49 years: 1.9%; 50-64 years: 2.4%; ≥65 years: 3.5%).

CONCLUSION

Findings were consistent for executive function impairment. While cognitive impairment increases with age, younger KT candidates have a high burden comparable to community-dwelling older adults, with some potentially suffering from severe forms. Transplant centers should consider routinely screening patients during clinical care encounters regardless of age.

Changes in Functional Status Among Kidney Transplant Recipients: Data From the Scientific Registry of Transplant Recipients

BACKGROUND

With stressors of dialysis prekidney transplantation (KT) and restoration of kidney function post-KT, it is likely that KT recipients experience a decline in functional status while on the waitlist and improvements post-KT.

METHODS

We leveraged 224 832 KT recipients from the national registry (SRTR, February 1990-May 2019) with measured Karnofsky Performance Status (KPS, 0%-100%) at listing, KT admission, and post-KT. We quantified the change in KPS from listing to KT using generalized linear models. We described post-KT KPS trajectories using adjusted mixed-effects models and tested whether those trajectories differed by age, sex, race, and diabetes status using a Wald test among all KT recipients. We then quantified risk adverse post-KT outcomes (mortality and all-cause graft loss [ACGL]) by preoperative KPS and time-varying KPS.

RESULTS

Mean KPS declined from listing (83.7%) to admission (78.9%) (mean = 4.76%, 95% confidence interval [CI]: -4.82, -4.70). After adjustment, mean KPS improved post-KT (slope = 0.89%/y, 95% CI: 0.87, 0.91); younger, female, non-Black, and diabetic recipients experienced greater post-KT improvements (Pinteractions < 0.001). Lower KPS (per 10% decrease) at admission was associated with greater mortality (adjusted hazard ratio [aHR] = 1.11, 95% CI: 1.10, 1.11) and ACGL (aHR = 1.08, 95% CI: 1.08, 1.09) risk. Lower post-KT KPS (per 10% decrease; time-varying) were more strongly associated with mortality (aHR = 1.93, 95% CI: 1.92, 1.94) and ACGL (aHR = 1.84, 95% CI: 1.83, 1.85).

CONCLUSIONS

Functional status declines pre-KT and improves post-KT in the national registry. Despite post-KT improvements, poorer functional status at KT and post-KT are associated with greater mortality and ACGL risk. Because of its dynamic nature, clinicians should repeatedly screen for lower functional status pre-KT to refer vulnerable patients to prehabilitation in hopes of reducing risk of adverse post-KT outcomes.

Development and Validation of an Inflammatory-Frailty Index for Kidney Transplantation

BACKGROUND

Physical frailty phenotype is characterized by decreased physiologic reserve to stressors and associated with poor outcomes, such as delirium and mortality, that may result from post-kidney transplant (KT) inflammation. Despite a hypothesized underlying pro-inflammatory state, conventional measures of frailty typically do not incorporate inflammatory biomarkers directly. Among KT candidates and recipients, we evaluated the inclusion of inflammatory biomarkers with traditional physical frailty phenotype components.

METHODS

Among 1154 KT candidates and recipients with measures of physical frailty phenotype and inflammation (interleukin 6 [IL6], tumor necrosis factor alpha [TNFα], C-reactive protein [CRP]) at 2 transplant centers (2009-2017), we evaluated construct validity of inflammatory-frailty using latent class analysis. Inflammatory-frailty measures combined 5 physical frailty phenotype components plus the addition of an individual inflammatory biomarkers, separately (highest tertiles) as a sixth component. We then used Kaplan-Meier methods and adjusted Cox proportional hazards to assess post-KT mortality risk by inflammatory-frailty (n = 378); Harrell's C-statistics assessed risk prediction (discrimination).

RESULTS

Based on fit criteria, a 2-class solution (frail vs nonfrail) for inflammatory-frailty was the best-fitting model. Five-year survival (frail vs nonfrail) was: 81% versus 93% (IL6-frailty), 87% versus 89% (CRP-frailty), and 83% versus 91% (TNFα-frailty). Mortality was 2.07-fold higher for IL6-frail recipients (95% CI: 1.03-4.19, p = .04); there were no associations between the mortality and the other inflammatory-frailty indices (TNFα-frail: 1.88, 95% CI: 0.95-3.74, p = .07; CRP-frail: 1.02, 95% CI: 0.52-2.03, p = .95). However, none of the frailty-inflammatory indices (all C-statistics = 0.71) improved post-KT mortality risk prediction over the physical frailty phenotype (C-statistics = 0.70).

CONCLUSIONS

Measurement of IL6-frailty at transplantation can inform which patients should be targeted for pre-KT interventions. However, the traditional physical frailty phenotype is sufficient for post-KT mortality risk prediction.

The Effect of Patient-controlled Intravenous Analgesia (PCIA) on Postoperative Delirium in Patients with Liver Transplantation: a Propensity Score Matching Analysis

Objectives Postoperative opioid use and pain are related to postoperative delirium. This study aims to compare the incidence of delirium in patients with and without patient-controlled intravenous analgesia (PCIA) among liver transplant recipients. Methods The medical records of 253 patients who received liver transplantation (LT) from January 2010 to July 2017 in a single university hospital were retrospectively reviewed. Patients were divided into two groups: the patients who had used PCIA (P group, n = 71) and those who did not use PCIA (C group, n = 182) after LT in intensive care unit (ICU). The patient data were collected, which included demographic data, and details about perioperative management and postoperative complications. Results There was no difference in the model for end-stage liver disease (MELD) score between the two groups. Postoperative delirium occurred in 10 / 71 (14.08 %) in the P group and 26 / 182 (14.29 %) in the C group after LT, respectively (P = 0.97). After propensity score matching, no differences were observed in the incidence of delirium (P = 0.359) and the time from surgery to discharge (P = 0.26) between the two groups. Conclusions Patients with PCIA after LT exhibited no relationship with postoperative delirium. Therefore, it is necessary to actively control postoperative pain using PCIA.

Frailty and Kidney Transplantation: A Systematic Review and Meta-analysis

Frailty is a multidimensional condition and is the result of the body's age-associated decline in physical, cognitive, physiological, and immune reserves. The aim of this systematic review is to assess the quality of evidence of the included studies, determine the prevalence of frailty among kidney transplant candidates, and evaluate the relationship between frailty and associated patient characteristics and outcomes after kidney transplantation.

METHODS

A systematic search was performed for relevant literature on frailty and kidney transplantation. This was followed by a meta-analysis for patient characteristics and outcomes reported by a minimum of 2 studies including mean age, gender, mean body mass index, type of kidney transplantation, dialysis, previous kidney transplantation, comorbidities, hypertension, race, preemptive kidney transplantation, delayed graft function, and length of stay.

RESULTS

A total of 18 studies were included in the systematic review and 14 of those studies were suitable for meta-analysis. The overall pooled prevalence of frailty before transplantation was estimated at 17.1% (95% confidence interval [CI], 15.4-18.7). Frailty was significantly associated with higher age (mean difference, 3.6; 95% CI, 1.4-5.9), lower rate of preemptive transplantation (relative risk, 0.60; 95% CI, 0.4-0.9), longer duration of delayed graft function (relative risk, 1.80; 95% CI, 1.1-3.0), and length of stay longer than 2 wk (odds ratio, 1.64; 95% CI, 1.2-2.3).

CONCLUSIONS

One in 6 kidney transplant recipients is frail before transplantation. The presence of frailty is associated with lower rates of preemptive transplantation, older recipient age, higher rates of delayed graft function, and longer length of stay. Future research is required to explore the association of frailty with other adverse outcomes after kidney transplantation and the effects of intervention programs to improve the different frailty domains.

Delirium Among Adults Undergoing Solid Organ Transplantation

Purpose of Review

To summarize the research on post-operative delirium among patients undergoing solid organ transplantation in efforts to improve recognition, evaluation, and management, as well as highlight areas for future research.

Recent Findings

Delirium is a common complication in patients with organ failure before and after undergoing solid organ transplant (range: 4.7-47%). However, it is frequently unrecognized and underdiagnosed-even among those closely monitored after major surgery-given that its manifestation is often variable and inconsistent. Delirium has multifactorial etiologies comprising of a complex mix of predisposing recipient, donor, and transplant factors, as well as intraoperative and perioperative factors. Evidence suggests that delirium risk increases with presence of a greater number of such risk factors, and can lead to adverse outcomes such as increased hospital length of stay, time in the ICU, time on mechanical ventilators, graft dysfunction, graft loss, and mortality. Though no trials have been conducted among transplant populations specifically, delirium has been shown to be preventable among hospitalized older adults generally. Multicomponent, primary prevention strategies designed to target multiple risk factors of delirium, such as cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration, have been identified as most effective. Whether these approaches translate to improvements in quality of life and long-term health outcomes among patients with organ failure before and after transplantation is yet to be determined.

Summary

Delirium is an important, common, yet potentially preventable complication among patients with organ failure. Future studies are needed to test the efficacy of multicomponent, primary prevention strategies on long-term health outcomes among these vulnerable populations.

[Kidney transplantation in the elderly: A benefit for all patients?]

Age per se should not be a contraindication to kidney transplantation. The first studies have shown a benefit for the survival of elderly eligible patients getting a kidney transplant compared to be maintained on the waiting list. However, more recent data suggest that this benefit is not as constant, notably with a significant early mortality period. The eligibility of elderly patients for transplantation must be based on the usual consideration of co-morbidities, but should also include, for some patients, a geriatric evaluation to detect clinical symptoms of frailty. The decision to transplant an elderly recipient must also integrate the characteristics of the donors, since the use of donors with increasingly expanding criteria can have a negative impact on the survival of these patients.

The Association Between Frailty and Delirium Among Hospitalized Patients: An Updated Meta-Analysis

OBJECTIVE

The aim of our meta-analysis was to update evidence for the association between frailty and delirium in different types of hospitalized patients, given the large volume of new studies with inconsistent results.

DESIGN

Systematic review and meta-analysis.

SETTING AND PARTICIPANTS

In this updated meta-analysis, we searched 3 databases (Embase, PubMed, and the Cochrane Library) for observational studies, exploring the association between frailty and delirium from database inception to September 21, 2020, among hospitalized patients. Relevant data were extracted from the studies that were included. A random effects model was conducted to synthesize and pool the effect size of frailty on delirium due to different frailty score instruments, different countries, and various delirium assessments that were used. The participants enrolled in this meta-analysis were hospitalized patients.

MEASURES

Delirium risk due to frailty.

RESULTS

A total of 30 independent studies from 9 countries, consisting of 217,623 patients, was identified, and the prevalence of frailty ranged from 16.20% to 78.00%. Frail patients exhibited an increased risk for delirium compared to those without frailty [odds ratio (OR) 2.96, 95% confidence interval (CI) 2.36-3.71]. In addition, different types of hospitalized patients had various OR values, which were 2.43 for selective surgical patients (95% CI 1.88-3.14), 3.61 for medical patients (95% CI 3.61-7.89), 3.76 for urgent surgical patients (95% CI 2.88-4.92), and 6.66 for emergency or critical illness patients (95% CI 1.41-31.47). Subgroup analysis based on the frailty score instrument showed the association still existed when using the Clinical Frailty Scale (OR 4.07, 95% CI 2.71-6.11), FRAIL Scale (OR 2.83, 95% CI 1.56-5.13), Frailty Index (OR 6.15, 95% CI 3.75-10.07), frailty phenotype (OR 2.30, 95%CI 1.35-5.66), or Erasmus Frailty Score (OR 2.79, 95% CI 1.63-4.77). However, an association between frailty and delirium was not observed when the Edmonton Frail Scale was used (OR 1.45, 95% CI 0.91-2.30).

CONCLUSIONS AND IMPLICATIONS

A 2.96-fold incremental risk of delirium in frail patients underscores the need for early screening of frailty and comprehensive delirium prevention. Appropriate interventions by clinicians should be performed to manage delirium, potentially reducing adverse clinical outcomes for hospitalized patients.

Interventions to Preserve Cognitive Functioning Among Older Kidney Transplant Recipients

PURPOSE OF REVIEW

To summarize the research on effective interventions for preserving cognitive function and prevent cognitive decline in patients with end-stage kidney disease (ESKD) who are undergoing dialysis and/or kidney transplantation (KT).

RECENT FINDINGS

Among ESKD patients undergoing hemodialysis, exercise training has been administered through home-based and intradialytic interventions. Additionally, one pilot study identified intradialytic cognitive training, electronic brain games, as an intervention to preserve cognitive function among patients undergoing hemodialysis. Fewer studies have investigated interventions to preserver cognitive function among KT recipients. To date, the only randomized controlled trial in this population identified B-vitamin supplements as an intervention to preserve cognitive function. The evidence from these trials support a short-term benefit of cognitive and exercise training as well as B-vitamin supplementation among patients with ESKD. Future studies should: 1) replicate these findings, 2) identify interventions specific to KT candidates, and 3) investigate the synergistic impact of both cognitive and exercise training.

SUMMARY

Cognitive prehabilitation, with cognitive and/or exercise training, may be novel interventions for KT candidates that not only reduces delirium risk and long-term post-KT cognitive decline but also prevents dementia.

An overview of frailty in kidney transplantation: measurement, management and future considerations

The construct of frailty was first developed in gerontology to help identify older adults with increased vulnerability when confronted with a health stressor. This article is a review of studies in which frailty has been applied to pre- and post-kidney transplantation (KT) populations. Although KT is the optimal treatment for end-stage kidney disease (ESKD), KT candidates often must overcome numerous health challenges associated with ESKD before receiving KT. After KT, the impacts of surgery and immunosuppression represent additional health stressors that disproportionately impact individuals with frailty. Frailty metrics could improve the ability to identify KT candidates and recipients at risk for adverse health outcomes and those who could potentially benefit from interventions to improve their frail status. The Physical Frailty Phenotype (PFP) is the most commonly used frailty metric in ESKD research, and KT recipients who are frail at KT (~20% of recipients) are twice as likely to die as nonfrail recipients. In addition to the PFP, many other metrics are currently used to assess pre- and post-KT vulnerability in research and clinical practice, underscoring the need for a disease-specific frailty metric that can be used to monitor KT candidates and recipients. Although frailty is an independent risk factor for post-transplant adverse outcomes, it is not factored into the current transplant program risk-adjustment equations. Future studies are needed to explore pre- and post-KT interventions to improve or prevent frailty.

A Systematic Review of Postoperative Delirium in the Urologic Patient

PURPOSE OF REVIEW

Postoperative delirium (POD) is a common phenomenon among general surgery patients, but it is not well described in urologic surgical patients. We sought to define the incidence and predictive risk factors for POD in patients undergoing urologic surgery.

RECENT FINDINGS

Eighteen articles were included for review. The pooled incidence rate of postoperative delirium after urologic surgery was 1.69% (0.69-46.97%). Longer intraoperative time, male sex, unmarried status, and age were shown to be risk factors for POD. POD is common after many urologic surgeries and leads to worse postoperative outcomes and higher healthcare utilization. Future studies are needed to better assess for and prevent POD.

A 'real-world' analysis of risk factors for post liver transplant delirium and the effect on length of stay

BACKGROUND

The development of delirium has been previously demonstrated to be associated with an increased risk of mortality and length of stay post liver transplant (LTx) with multiple risk factors being identified in previous studies. In this study, we have aimed to identify the most important variables associated with the onset of post-LTx delirium and understand the effect on length of stay (LOS).

METHODS

All liver transplants for chronic liver disease between 1 August 2012 and 1 August 2017 were included (n = 793). Data were collected for analysis retrospectively from electronic patient records.

RESULTS

Delirium is associated with an overall increased hospital and ICU LOS but not one-year mortality. The risk of developing post-LTx delirium was the greatest among patients: with post-LTx sepsis, who required renal sparing immunosuppression, who received donation after cardiac death (DCD) grafts and who were older. Patients with autoimmune hepatitis, primary biliary cholangitis or primary sclerosing cholangitis seemed to be at lower risk of post-LTx delirium. However, global patient LOS was only prolonged in patients with sepsis and renal failure.

CONCLUSION

Many of the risk factors previously described to be associated with the development of post-LTx delirium were not demonstrated to be significant in this study. Sepsis, renal failure, older age and DCD use are associated with delirium post-LTx. It is unclear if this syndrome is an independent risk factor for increased LOS or if it is a symptom of well established syndromes associated with increased LOS. The role for prophylactic strategies to reduce the incidence of post-LTx delirium is therefore unclear.

Clinical and Neuroimaging Correlates of Post-Transplant Delirium

Delirium is common among adults undergoing hematopoietic stem cell transplantation (HCT), although the clinical and neuroimaging correlates of post-HCT delirium have not been adequately delineated. We therefore examined the frequency of delirium and neuroimaging correlates of post-transplant delirium in a retrospective cohort of 115 adults undergoing neuroimaging after allogeneic HCT. Delirium was established using previously validated methods for retrospective identification of chart-assessed postprocedural delirium. Chart reviews were independently conducted by a multidisciplinary team with expertise in HCT, psychiatry, and psychology on consecutive allogeneic HCT patients who underwent neuroimaging assessments and transplantation at a single center between January 2009 and December 2016. Neuroimaging markers of white matter damage and brain volume loss were also recorded. In total, 115 patients were included, ranging in age from 20 to 74 years (mean [SD] age, 49 [13]). Fifty-three patients (46%) developed post-HCT delirium. In an adjusted model, delirium incidence was associated with older age (odds ratio [OR], 1.92 [1.28, 2.87] per decade, P = .002), greater severity of white matter hyperintensities (OR, 1.95 [1.06, 3.57], P = .031), and conditioning intensity (OR, 6.37 [2.20, 18.45], P < .001) but was unrelated to cortical atrophy (P = .777). Delirium was associated with fewer hospital-free days (P = .023) but was not associated with overall survival (hazard ratio, 0.95 [0.56, 1.61], P = .844). Greater incidence of delirium following HCT was associated with greater age, microvascular burden, and conditioning intensity. Pre-HCT consideration of microvascular burden and other neuroimaging biomarkers of risk may be warranted.