Frailty and mortality in kidney transplant recipients

Frailty, but not cognitive impairment, improves mortality risk prediction among those with chronic kidney disease-a nationally representative study

BACKGROUND

Though older adults with chronic kidney disease (CKD) have a greater mortality risk than those without CKD, traditional risk factors poorly predict mortality in this population. Therefore, we tested our hypothesis that two common geriatric risk factors, frailty and cognitive impairment, and their co-occurrence, might improve mortality risk prediction in CKD.

METHODS

Among participants aged ≥ 60 years from National Health and Nutrition Examination Survey (2011-2014), we quantified associations between frailty (physical frailty phenotype) and global/domain-specific cognitive function (immediate-recall [CERAD-WL], delayed-recall [CERAD-DL], verbal fluency [AF], executive function/processing speed [DSST], and global [standardized-average of 4 domain-specific tests]) using linear regression, and tested whether associations differed by CKD using a Wald test. We then tested whether frailty, global cognitive impairment (1.5SD below the mean), or their combination improved prediction of mortality (Cox models, c-statistics) compared to base models (likelihood-ratios) among those with and without CKD.

RESULTS

Among 3,211 participants, 1.4% were cognitively impaired, and 10.0% were frail; frailty and cognitive impairment co-occurrence was greater among those with CKD versus those without (1.2%vs.0.1%). Frailty was associated with worse global cognitive function (Cohen's d = -0.26SD,95%CI -0.36,-0.17), and worse cognitive function across all domains; these associations did not differ by CKD (pinteractions > 0.05). Mortality risk prediction improved only among those with CKD when accounting for frailty (p[likelihood ratio test] < 0.001) but not cognitive impairment.

CONCLUSIONS

Frailty is associated with worse cognitive function regardless of CKD status. While CKD and frailty improved mortality prediction, cognitive impairment did not. Risk prediction tools should incorporate frailty to improve mortality prediction among those with CKD.

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.

Pretransplant Malnutrition, Particularly With Muscle Depletion Is Associated With Adverse Outcomes After Kidney Transplantation

Background

Kidney transplant centers lack consistent diagnostic malnutrition tools. The Academy of Nutrition and Dietetics and American Society of Parenteral Nutrition Adult Malnutrition Criteria (AMC) is the widely accepted and utilized tool by Registered Dietitian Nutritionists (RDNs) to diagnose malnutrition.

Methods

In this single-center, retrospective observational study, we evaluated the outcomes of prekidney transplant malnutrition based on Academy of Nutrition and Dietetics and American Society of Parenteral Nutrition AMC, as well as the individual components of the AMC, on posttransplant outcomes including length of stay, delayed graft function (DGF), early readmission, cardiovascular events, acute rejection, death-censored graft failure, and death. Bivariable and multivariable logistic regression models were used to assess the association of malnutrition or its components with outcomes of interest.

Results

A total of 367 recipients were included, of whom 36 (10%) were malnourished (23 moderately and 13 severely) at pretransplant evaluation. In adjusted models, pretransplant malnutrition was significantly associated with increased risk for early readmission (adjusted odds ratio 2.86; 95% confidence interval: 1.14-7.21; P = 0.03) and with DGF (adjusted odds ratio 8.33; 95% confidence interval: 1.07-64.6; P = 0.04). Muscle depletion was also associated with an increased risk for readmission and with DGF. Fat depletion and reduced functionality in the adjusted model were only associated with increased risk for readmission.

Conclusions

Malnutrition could be an important consideration for selecting kidney transplant recipients because it was associated with poor clinical outcomes. A multidisciplinary approach with the involvement of RDNs to outline a nutrition intervention plan may help mitigate some of the poor outcomes.

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.

Narrative Review: Clinical Implications and Assessment of Frailty in Patients With Advanced CKD

Frailty is a multidimensional clinical syndrome characterized by low physical activity, reduced strength, accumulation of multiorgan deficits, decreased physiological reserve, and vulnerability to stressors. Frailty has key social, psychological, and cognitive implications. Frailty is accelerated by uremia, leading to a high prevalence of frailty in patients with advanced chronic kidney disease (CKD) and end-stage kidney disease (ESKD) as well as contributing to adverse outcomes in this patient population. Frailty assessment is not routine in patients with CKD; however, a number of validated clinical assessment tools can assist in prognostication. Frailty assessment in nephrology populations supports shared decision-making and advanced communication and should inform key medical transitions. Frailty screening and interventions in CKD or ESKD are a developing research priority with a rapidly expanding literature base.

[Comprehensive care for kidney transplantation-optimization of interdisciplinary support before and after kidney transplantation]

Due to the divergence between the number of potential organ recipients and organ availability, transplant survival is of particular importance. In order to create the best possible conditions, it is not only important to address the risk factors for loss of organ functionality after transplantation, but also to focus on the time before transplantation. During this period, which lasts several years on average, the patient can create the conditions for risk reduction before and after transplantation with support. The optimization of physical health plays an important role here in order to maintain transplantability, on the one hand, and to counteract the general loss of physical performance due to dialysis, on the other. Therefore, the focus must be placed on "exercise" and "nutrition", which represent an increased risk of declining physical health in dialysis patients. After transplantation, the focus should again be on physical health. Through support, patients learn how to improve their cardiovascular risk profile and increase their physical performance. Psychosocial support is also important to combat psychological comorbidities and prevent risks such as nonadherence. In addition to improved physical and mental health, the focus here is also on the long-term survival of the patient and the transplant.

Frailty and Cardiovascular Outcomes in Adults With CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVE

Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes in adults with kidney failure requiring dialysis. However, this relationship has not been thoroughly evaluated among those with non-dialysis-dependent CKD.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

2,539 adults in the Chronic Renal Insufficiency Cohort Study.

EXPOSURE

Frailty status assessed using 5 criteria: slow gait speed, muscle weakness, low physical activity, exhaustion, and unintentional weight loss.

OUTCOME

Atherosclerotic events, incident heart failure, all-cause death, and cardiovascular death.

ANALYTICAL APPROACH

Cause-specific hazards models.

RESULTS

At study entry, the participants' mean age was 62 years, 46% were female, the mean estimated glomerular filtration rate was 45.4mL/min/1.73m2, and the median urine protein was 0.2mg/day. Frailty status was as follows: 12% frail, 51% prefrail, and 37% nonfrail. Over a median follow-up of 11.4 years, there were 393 atherosclerotic events, 413 heart failure events, 497 deaths, and 132 cardiovascular deaths. In multivariable regression analyses, compared with nonfrailty, both frailty and prefrailty status were each associated with higher risk of an atherosclerotic event (HR, 2.03 [95% CI, 1.41-2.91] and 1.77 [95% CI, 1.35-2.31], respectively) and incident heart failure (HR, 2.22 [95% CI, 1.59-3.10] and 1.39 [95% CI, 1.07-1.82], respectively), as well as higher risk of all-cause death (HR, 2.52 [95% CI, 1.84-3.45] and 1.76 [95% CI, 1.37-2.24], respectively) and cardiovascular death (HR, 3.01 [95% CI, 1.62-5.62] and 1.78 [95% 1.06-2.99], respectively).

LIMITATIONS

Self-report of aspects of the frailty assessment and comorbidities, which may have led to bias in some estimates.

CONCLUSIONS

In adults with CKD, frailty status was associated with higher risk of cardiovascular events and mortality. Future studies are needed to evaluate the impact of interventions to reduce frailty on cardiovascular outcomes in this population.

PLAIN-LANGUAGE SUMMARY

Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes. We sought to evaluate the association of frailty status with cardiovascular events and death in adults with CKD. Frailty was assessed according to the 5 phenotypic criteria detailed by Fried and colleagues. Among 2,539 participants in the CRIC Study, we found that 12% were frail, 51% were prefrail, and 37% were nonfrail. Frailty status was associated with an increased risk of atherosclerotic events, incident heart failure, and death.

Assessing nutrition status, sarcopenia, and frailty in adult transplant recipients

The assessment of nutrition status, sarcopenia, and frailty holds significant relevance in the context of adult transplantation, as these factors are associated with an unfavorable prognosis; thus, transplant candidates must undergo a full nutrition assessment. Screening tools may be used to prioritize patients, this can be done using the Nutrition Risk Screening 2002 or Royal Free Hospital-Nutritional Prioritizing Tool. Subsequently, a thorough nutrition-focused physical examination should be conducted to evaluate clinical signs of nutrition deficiencies, fat and muscle loss, and fluid overload; dietary history and current intake must also be assessed. Apart from physical examination, specific testing for sarcopenia and frailty are recommended. For sarcopenia assessment, specifically for muscle quantification, the gold standard is the cross-sectional measurement of the muscle at L3 obtained from a computed tomography scan or magnetic resonance imaging; dual-energy x-ray absorptiometry is also a good tool especially when appendicular skeletal muscle index is calculated. Other more readily available options include phase angle from bioelectrical impedance or bioimpedance spectroscopy. In the sarcopenia assessment, muscle function evaluation is required, handgrip strength stands as the primary test for this purpose; this test is also part of the subjective global assessment and is included in some frailty scores. Finally, for frailty assessment, the Short Physical Performance Battery is useful for evaluating physical frailty, and for a multidimensional evaluation, the Fried frailty phenotype can be used. Specifically for liver transplant candidates, the use of Liver Frailty Index is recommended.

Do pre-transplant cultural factors predict health-related quality of life after kidney transplantation?

BACKGROUND

Post-transplant health-related quality of life (HRQOL) is associated with health outcomes for kidney transplant (KT) recipients. However, pretransplant predictors of improvements in post-transplant HRQOL remain incompletely understood. Namely, important pretransplant cultural factors, such as experience of discrimination, perceived racism in healthcare, or mistrust of the healthcare system, have not been examined as potential HRQOL predictors. Also, few have examined predictors of decline in HRQOL post-transplant.

METHODS

Using data from a prospective cohort study, we examined HRQOL change pre- to post-transplant, and novel cultural predictors of the change. We measured physical, mental, and kidney-specific HRQOL as outcomes, and used cultural factors as predictors, controlling for demographic, clinical, psychosocial, and transplant knowledge covariates.

RESULTS

Among 166 KT recipients (57% male; mean age 50.6 years; 61.4% > high school graduates; 80% non-Hispanic White), we found mental and physical, but not kidney-specific, HRQOL significantly improved post-transplant. No culturally related factors outside of medical mistrust significantly predicted change in any HRQOL outcome. Instead, demographic, knowledge, and clinical factors significantly predicted decline in each HRQOL domain: physical HRQOL-older age, more post-KT complications, higher pre-KT physical HRQOL; mental HRQOL-having less information pre-KT, greater pre-KT mental HRQOL; and, kidney-specific HRQOL-poorer kidney functioning post-KT, lower expectations for physical condition to improve, and higher pre-KT kidney-specific HRQOL.

CONCLUSIONS

Instead of cultural factors, predictors of HRQOL decline included demographic, knowledge, and clinical factors. These findings are useful for identifying patient groups that may be at greater risk of poorer post-transplant outcomes, in order to target individualized support to patients.

Baduanjin exercise intervention trial: research protocol of a randomised controlled trial for frail kidney transplant recipients

INTRODUCTION

Frailty is one of the most common comorbidities in kidney transplant recipients (KTRs). Physical, psychological and social frailty could be improved by exercise intervention. Baduanjin, also known as Eight-section Brocades, is a type of traditional Chinese medicine exercise characterised by the interplay between physical postures and movements, breathing and mind. It can help frail patients strengthen their upper and lower body muscles, improve their mood, quality of life and frailty. However, the effectiveness of Baduanjin on frail KTRs remains unknown. Therefore, we will conduct a randomised controlled trial (RCT) to evaluate the effectiveness of Baduanjin on frail KTRs.

METHODS AND ANALYSIS

This protocol describes an assessor and analyst blinded, parallel RCT for frail KTRs comparing Baduanjin group (n=72) with care-as-usual group (n=72). The primary outcomes are frailty assessed by Frailty Phenotype scale and Tilburg Frailty Indicator scale, and muscle strength assessed by a grip strength metre. The secondary outcomes are quality of life assessed by Medical Outcomes Study 36-Item Short-Form Health Survey (MOS SF-36) and depression assessed by the Hospital Anxiety and Depression Scale. All these data will be collected at the baseline, after 3, 6, 9 and 12 months, respectively. Two-way mixed analysis of variance (ANOVA) will be used to test the effectiveness of Baduanjin exercise. Qualitative interviews with participants in the intervention group will also be performed after 6 months. Themes will be extracted from interview transcripts using NVivo software.

ETHICS AND DISSEMINATION

The Ethics Committees of Beijing University of Chinese Medicine (2022BZYLL1018) and China-Japan Friendship Hospital (2022-KY-250) had approved the study. The organ donors were all from China-Japan Friendship Hospital. They provided informed consent and they were not executed prisoners. We have provided BMJ Open with documentation from the hospital that indicates that the organs will be harvested ethically. The findings of this study will be disseminated through peer-reviewed journals, international conferences, media reports and briefings.

TRIAL REGISTRATION NUMBER

ChiCTR2100041730.

Administrative coding of frailty: Its association with clinical outcomes and resource use in kidney transplantation

INTRODUCTION

Although not formalized into current risk assessment models, frailty has been associated with negative postoperative outcomes in many specialties. However, national analyses of the association between frailty and post-transplant outcomes following kidney transplantation (KT) are lacking.

METHODS

This was a retrospective cohort study of adults undergoing KT from 2016 to 2020 in the Nationwide Readmissions Databases. Frailty was defined using the Johns Hopkins Adjusted Clinical Groups frailty indicator.

RESULTS

Of an estimated 95 765 patients undergoing KT during the study period, 4918 (5.1%) were frail. After risk adjustment, frail patients were associated with significantly higher odds of in-hospital mortality (AOR 2.17, 95% CI: 1.33-3.57) compared to their non-frail counterparts. Our findings indicate that frail patients had an average increase in postoperative hospital stay of 1.44 days, a $2300 increase in hospitalization costs, as well as higher odds of developing a major perioperative complication as compared to their non-frail counterparts. Frailty was also associated with greater adjusted risk of non-home discharge.

CONCLUSIONS

Frailty, as identified by administrative coding, is independently associated with worse surgical outcomes, including increased mortality and resource use, in adults undergoing KT. Given the already limited donor organ pool, novel efforts are needed to ensure adequate optimization and timely post-transplantation care of the growing frail cohort undergoing KT.

Kidney retransplantation outcomes in adults aged 70 and older: Analysis of risk factors and survival

BACKGROUND

An increasing number of older patients are undergoing kidney transplant. Because of a finite longevity, more patients will be faced with failing allografts. At present there is a limited understanding of the benefits and risks associated with kidney retransplantation in this challenging population.

METHODS

We performed a retrospective analysis of the Organ Procurement and Transplantation Network database of all adults ≥70 undergoing kidney retransplant from January 1, 2014 to December 31, 2022. We examined patient and graft survival of retransplanted patients compared to first time transplants. We also analyzed the risk factors that impacted the survival.

RESULTS

During the study period there has been a significant rise in the number of retransplants performed, with 631 patients undergoing the procedure. Although clinically insignificant, overall graft, and patient survival rates were slightly lower in the retransplant group compared to the primary transplant group. With retransplant, patient survival was 91.3%, 75.6%, and 56.9% compared to 93.4%, 81.4%, and 64.4% with primary transplant at 1, 3, and 5 years, respectively. With retransplant, graft survival was 89.5%, 73.5%, 57.4% compared to 91.5%, 79.0%, and 63.6% in a primary transplant group at 1, 3, and 5 years, respectively. Multivariable analysis showed that factors predicting poor survival included longer time on dialysis before retransplantation and decreased functional capacity. No survival difference was noted between recipients of deceased versus living donor kidneys. Patients who underwent retransplantation before initiating dialysis had better patient and graft survival.

CONCLUSION

Patients aged ≥70 achieve satisfactory outcomes following kidney retransplantation, highlighting that chronologic age should not preclude this medically complex population from this life-saving procedure. Improvement in functional status and timely retransplantation are the key factors to successful outcome.

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.

Physical Frailty Predicts Outcomes in Patients Undergoing Evaluation for Kidney Transplantation

INTRODUCTION

An increasing number of older patients are undergoing evaluation for kidney transplantation; however, older patients experience increased rates of complications compared with younger patients, leading to the study of frailty assessments. Although many centers have evaluated the Fried Frailty Phenotype (FFP), less is known about the ability of the Short Performance Physical Battery (SPPB) to predict outcomes.

METHODS

Frailty assessment by FFP and SPPB was introduced into routine outpatient evaluation for patients aged 55 years and older referred for transplantation. Transplant rate, length of stay, readmission up to 3 months posttransplant, and death were reviewed. Patients were evaluated in an initial cohort followed by a validation cohort by FFP and SPPB. Multivariate analysis correcting for demographic characteristics was applied.

RESULTS

Patient cohorts reflected the racial and ethnic diversity of our population, including approximately 40% Hispanic patients. The first cohort of 514 patients demonstrated a significant association between frailty as measured by SPPB and transplantation (odds ratio [OR], 2.27; 95% CI, 1.38-3.83; p = .002). The second cohort of 1408 patients validated the association between frailty measured by SPPB and transplantation (OR, 2.81; 95% CI, 1.83-4.48; p < .001). In addition, there was a significant association between nonfrail status measured by SPPB and death (OR, 0.16; 95% CI, 0.04-0.62; p = .006).

CONCLUSIONS

Frailty assessment is a potentially useful approach for the assessment of transplant candidates. Our real-world study examined the performance of 2 methods of frailty evaluation methods in a diverse population, demonstrating that SPPB but not FFP was predictive of clinical outcomes. Incorporation of frailty assessments into transplant evaluation may improve risk stratification and optimize outcomes for older patients.

Association of frailty with postoperative outcomes following thoracic transplantation: A national analysis

Objective

Frailty has been repeatedly associated with inferior outcomes after surgical hospitalizations. However, a thorough evaluation of the impact of frailty on the clinical and financial outcomes of patients undergoing solid-organ thoracic transplantation is sparse in the literature. We evaluated the association of frailty, as determined by an administrative tool, with postoperative outcomes and healthcare resource use after heart or lung transplantation.

Methods

The Nationwide Readmissions Database was used to identify all adult hospitalizations for heart or lung transplant from 2014 to 2020. Patients were grouped as frail or nonfrail using International Classification of Diseases codes associated with conditions in the Johns Hopkins Adjusted Clinical Groups cluster. Multivariable regression models were developed to evaluate the association of frailty status on in-hospital mortality, complications, length of stay, costs, and unplanned readmissions.

Results

Of an estimated 35,862 heart or lung transplant recipients, 7316 (20.4%) were considered frail. After multivariable adjustment, frailty in heart transplantation was associated with greater odds of in-hospital mortality (adjusted odds ratio, 1.54; 95% CI, 1.19-1.99) and infectious complications (adjusted odds ratio, 1.77; 95% CI, 1.45-2.15; P < .001). Frailty in lung transplantation was also associated with higher odds of in-hospital mortality (adjusted odds ratio, 1.38; 95% CI, 1.11-1.69) and infectious complications (adjusted odds ratio, 1.93; 95% CI, 1.60-2.31). In addition, frailty in both heart transplantation and lung transplantation was associated with increased postoperative length of stay and greater costs.

Conclusions

Among transplant recipients, those classified as frail were associated with increased in-hospital mortality, perioperative complications, and resource use.

Malnutrition in solid organ transplant patients: A review of the literature

Screening for malnutrition is of vital importance for solid organ transplant candidates to optimize nutrition status before transplant, to improve clinical outcomes and to inform selection committees of nutritional contraindications and risks. There are multiple criteria and screening tools available for determining malnutrition diagnosis and risk. Registered Dietitian Nutritionists use these tools for nutrition assessments to quantify the severity of malnutrition, provide patient-centered interventions, and monitor progression. Many transplant centers in the United States utilize the American Society of Parenteral and Enteral Nutrition and the Academy of Nutrition and Dietetics' Adult Malnutrition Criteria, though there is limited research using these criteria specifically in the transplant population. Malnutrition, utilizing other diagnostic and screening tools, has been associated with important complications, including longer length of hospital stay, increased mortality, decreased quality of life, worsened end-stage organ progression, and decreased functional status. Malnutrition typically results from sarcopenia and cachexia, and can ultimately lead to frailty, causing further negative impacts on transplant outcomes. This literature review summarizes the current research on malnutrition in solid organ transplant candidates and provides recommendations for future research and current practice implications.

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.

Frailty and prognosis of patients with kidney transplantation: a meta-analysis

BACKGROUND

The prevalence of frailty among candidates and recipients of kidney transplantation (KT) is well-established, yet the impact of frailty on clinical outcomes following KT remains uncertain. To address this knowledge gap, we conducted a systematic meta-analysis to comprehensively assess the aforementioned relationship.

METHODS

The present study conducted a comprehensive search of PubMed, Embase, and Cochrane Library databases to identify relevant observational studies that compared mortality risk and other clinical outcomes of KT recipients with and without frailty. Two authors independently conducted data collection, literature searching, and statistical analysis. The results were synthesized using a heterogeneity-incorporating random-effects model.

RESULTS

In this meta-analysis, 6279 patients from 13 cohort studies were included, and 1435 patients (22.9%) were with frailty before KT. There were higher mortality rates among frail patients at admission, compared to those without frailty (risk ratio [RR]: 1.97, 95% confidence interval [CI]: 1.57 to 2.47, p < 0.001; I2 = 19%). Subgroup analysis suggested the association between frailty and high mortality risk after KT was consistent in studies of frailty assessed via Physical Frailty Phenotype or other methods, and in studies of follow-up duration < or ≥ 5 years. In addition, frailty was associated with higher incidence of delayed graft function (RR: 1.78, 95% CI: 1.21 to 2.61, p = 0.003; I2 = 0%), postoperative complications (RR: 1.88, 95% CI: 1.15 to 3.08, p = 0.01; I2 = 0%), and longer hospitalization (RR: 1.55, 95% CI: 1.22 to 1.97, p < 0.001; I2 = 0%).

CONCLUSION

Following KT, frail patients are at higher risks for all-cause mortality, delayed graft function, postoperative complications, and longer hospital stays.

Frailty in the Advanced Heart Failure Patient: A Challenging, Neglected, Yet Potentially Modifiable Risk Factor

Purpose of review

There is an increasing push for frailty assessment to become a routine part of the evaluation of potential candidates for advanced heart failure (AHF) therapies. The aim of this review is to highlight the importance of frailty in the care of the AHF patient.

Recent findings

This review focuses on some of the available data for the assessment of frailty specifically in the AHF, durable mechanical circulatory support (MCS), and heart transplant (HT) patients, and explores some of the challenges in assessing frailty in these patient populations.

Summary

As the presence of frailty can significantly impact outcomes after HT and durable MCS implantation, there should be an increased recognition of this entity during routine evaluation and management of the AHF patient.

Substitution of self-reported measures for objectively assessed grip strength and slow walk in the Physical Frailty Phenotype: ramifications for validity

BACKGROUND

Frailty assessment promises to identify older adults at risk for adverse consequences following stressors and target interventions to improve health outcomes. The Physical Frailty Phenotype (PFP) is a widely-studied, well validated assessment but incorporates performance-based slow walk and grip strength criteria that challenge its use in some clinical settings. Variants replacing performance-based elements with self-reported proxies have been proposed. Our study evaluated whether commonly available disability self-reports could be substituted for the performance-based criteria in the PFP while still identifying as "frail" the same subpopulations of individuals.

METHODS

Parallel analyses were conducted in 3393 female and 2495 male Cardiovascular Health Study, Round 2 participants assessed in 1989-90. Candidate self-reported proxies for the phenotype's "slowness" and "weakness" criteria were evaluated for comparable prevalence and agreement by mode of measurement. For best-performing candidates: Frailty status (3 + positive criteria out of 5) was compared for prevalence and agreement between the PFP and mostly self-reported versions. Personal characteristics were compared between those adjudicated as frail by (a) only a self-reported version; (b) only the PFP; (c) both, using bivariable analyses and multinomial logistic regression.

RESULTS

Self-reported difficulty walking ½ mile was selected as a proxy for the phenotype's slowness criterion. Two self-reported weakness proxies were examined: difficulty transferring from a bed or chair or gripping with hands, and difficulty as just defined or in lifting a 10-pound bag. Prevalences matched to within 4% between self-reported and performance-based criteria in the whole sample, but in all cases the self-reported prevalence for women exceeded that for men by 11% or more. Cross-modal agreement was moderate, with by-criterion and frailty-wide Kappa statistics of 0.55-0.60 in all cases. Frail subgroups (a), (b), (c) were independently discriminated (p < 0.05) by race, BMI, and depression in women; by age in men; and by self-reported health for both.

CONCLUSIONS

Commonly used self-reported disability items cannot be assumed to stand in for performance-based criteria in the PFP. We found subpopulations identified as frail by resultant phenotypes versus the original phenotype to systematically differ. Work to develop self-reported proxies that more closely replicate their objective phenotypic counterparts than standard disability self-reports is needed.

Use of frailty assessment instruments in nephrology populations: a scoping review

BACKGROUND

Frailty is a clinical syndrome of accelerated aging associated with adverse outcomes. Frailty is prevalent among patients with chronic kidney disease but is infrequently assessed in clinical settings, due to lack of consensus regarding frailty definitions and diagnostic tools. This study aimed to review the practice of frailty assessment in nephrology populations and evaluate the context and timing of frailty assessment.

METHODS

The search included published reports of frailty assessment in patients with chronic kidney disease, undergoing dialysis or in receipt of a kidney transplant, published between January 2000 and November 2021. Medline, CINAHL, Embase, PsychINFO, PubMed and Cochrane Library databases were examined. A total of 164 articles were included for review.

RESULTS

We found that studies were most frequently set within developed nations. Overall, 161 studies were frailty assessments conducted as part of an observational study design, and 3 within an interventional study. Studies favoured assessment of participants with chronic kidney disease (CKD) and transplant candidates. A total of 40 different frailty metrics were used. The most frequently utilised tool was the Fried frailty phenotype. Frailty prevalence varied across populations and research settings from 2.8% among participants with CKD to 82% among patients undergoing haemodialysis. Studies of frailty in conservatively managed populations were infrequent (N = 4). We verified that frailty predicts higher rates of adverse patient outcomes. There is sufficient literature to justify future meta-analyses.

CONCLUSIONS

There is increasing recognition of frailty in nephrology populations and the value of assessment in informing prognostication and decision-making during transitions in care. The Fried frailty phenotype is the most frequently utilised assessment, reflecting the feasibility of incorporating objective measures of frailty and vulnerability into nephrology clinical assessment. Further research examining frailty in low and middle income countries as well as first nations people is required. Future work should focus on interventional strategies exploring frailty rehabilitation.

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.

Physiological Age by Artificial Intelligence-Enhanced Electrocardiograms as a Novel Risk Factor of Mortality in Kidney Transplant Candidates

BACKGROUND

Mortality risk assessment before kidney transplantation (KT) is imperfect. An emerging risk factor for death in nontransplant populations is physiological age as determined by the application of artificial intelligence to the electrocardiogram (ECG). The aim of this study was to examine the relationship between ECG age and KT waitlist mortality.

METHODS

We applied a previously developed convolutional neural network to the ECGs of KT candidates evaluated 2014 to 2019 to determine ECG age. We used a Cox proportional hazard model to examine whether ECG age was associated with waitlist mortality.

RESULTS

Of the 2183 patients evaluated, 59.1% were male, 81.4% were white, and 11.4% died during follow-up. Mean ECG age was 59.0 ± 12.0 y and mean chronological age at ECG was 53.3 ± 13.6 y. After adjusting for chronological age, comorbidities, and other characteristics associated with mortality, each increase in ECG age of >10 y than the average ECG age for patients of a similar chronological age was associated with an increase in mortality risk (hazard ratio 3.59 per 10-y increase; 95% confidence interval, 2.06-5.72; P  < 0.0001).

CONCLUSIONS

ECG age is a risk factor for KT waitlist mortality. Determining ECG age through artificial intelligence may help guide risk-benefit assessment when evaluating candidates for KT.

Frailty in kidney transplant candidates and recipients: pathogenesis and intervention strategies

ABSTRACT

With the rapid aging of the global population posing a serious problem, frailty, a non-specific state that reflects physiological senescence rather than aging in time, has become more widely addressed by researchers in various medical fields. A high prevalence of frailty is found among kidney transplant (KT) candidates and recipients. Therefore, their frailty has become a research hotspot in the field of transplantation. However, current studies mainly focus on the cross-sectional survey of the incidence of frailty among KT candidates and recipients and the relationship between frailty and transplantation. Research on the pathogenesis and intervention is scattered, and relevant review literature is scarce. Exploring the pathogenesis of frailty in KT candidates and recipients and determining effective intervention measures may reduce waiting list mortality and improve the long-term quality of life of KT recipients. Therefore, this review explains the pathogenesis and intervention measures for frailty in KT candidates and recipients to provide a reference for the formulation of effective intervention strategies.

Post-kidney transplant body mass index trajectories are associated with graft loss and mortality

BACKGROUND

Early post-kidney transplantation (KT) changes in physiology, medications, and health stressors likely impact body mass index (BMI) and likely impact all-cause graft loss and mortality.

METHODS

We estimated 5-year post-KT (n = 151 170; SRTR) BMI trajectories using an adjusted mixed effects model. We estimated long-term mortality and graft loss risks by 1-year BMI change quartile (decrease [1st quartile]: change < -.07 kg/m2 /month; stable [2nd quartile]: -.07 ≤ change ≤ .09 kg/m2 /month; increase [3rd, 4th quartile]: change > .09 kg/m2 /month) using adjusted Cox proportional hazards models.

RESULTS

BMI increased in the 3 years post-KT (.64 kg/m2 /year, 95% CI: .63, .64) and decreased in years 3-5 (-.24 kg/m2 /year, 95% CI: -.26, -.22). 1-year post-KT BMI decrease was associated with elevated risks of all-cause mortality (aHR = 1.13, 95% CI: 1.10-1.16), all-cause graft loss (aHR = 1.13, 95% CI: 1.10-1.15), death-censored graft loss (aHR = 1.15, 95% CI: 1.11-1.19), and mortality with functioning graft (aHR = 1.11, 95% CI: 1.08-1.14). Among recipients with obesity (pre-KT BMI≥30 kg/m2 ), BMI increase was associated with higher all-cause mortality (aHR = 1.09, 95% CI: 1.05-1.14), all-cause graft loss (aHR = 1.05, 95% CI: 1.01-1.09), and mortality with functioning graft (aHR = 1.10, 95% CI: 1.05-1.15) risks, but not death-censored graft loss risks, relative to stable weight. Among individuals without obesity, BMI increase was associated with lower all-cause graft loss (aHR = .97, 95% CI: .95-.99) and death-censored graft loss (aHR = .93, 95% CI: .90-.96) risks, but not all-cause mortality or mortality with functioning graft risks.

CONCLUSIONS

BMI increases in the 3 years post-KT, then decreases in years 3-5. BMI loss in all adult KT recipients and BMI gain in those with obesity should be carefully monitored post-KT.

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.

The role of frailty in advanced HF and cardiac transplantation

Frailty is a complex, multi-system condition often associated with multimorbidity. It has become an important prognostic maker across a range of conditions and is particularly relevant in patients with cardiovascular disease. Frailty encompasses a range of domains including, physical, psychological, and social. There are currently a range of validated tools available to measure frailty. It is an especially important measurement in advanced HF, because frailty occurs in up to 50% of HF patients and is potentially reversible with therapies such as mechanical circulatory support and transplantation. Moreover, frailty is dynamic, and therefore serial measurements are important. This review delves into the measurement of frailty, mechanisms, and its role in different cardiovascular cohorts. Understanding frailty will help determine patients that will benefit from therapies, as well as prognosticate outcomes.

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.

Computed tomography body composition and clinical outcomes following lung transplantation in cystic fibrosis

BACKGROUND

Low muscle mass is common in patients approaching lung transplantation and may be linked to worse post-transplant outcomes. Existing studies assessing muscle mass and post-transplant outcomes include few patients with cystic fibrosis (CF).

METHODS

Between May 1993 and December 2018, 152 adults with CF received lung transplants at our institution. Of these, 83 met inclusion criteria and had usable computed tomography (CT) scans. Using Cox proportional hazards regression, we evaluated the association between pre-transplant thoracic skeletal muscle index (SMI) and our primary outcome of death after lung transplantation. Secondary outcomes, including days to post-transplant extubation and post-transplant hospital and intensive care unit (ICU) length of stay, were assessed using linear regression. We also examined associations between thoracic SMI and pre-transplant pulmonary function and 6-min walk distance.

RESULTS

Median thoracic SMI was 26.95 cm²/m² (IQR 23.97, 31.32) for men and 22.83 cm²/m² (IQR 21.27, 26.92) for women. There was no association between pre-transplant thoracic SMI and death after transplant (HR 1.03; 95% CI 0.95, 1.11), days to post-transplant extubation, or post-transplant hospital or ICU length of stay. There was an association between pre-transplant thoracic SMI and pre-transplant FEV1% predicted (b = 0.39; 95% CI 0.14, 0.63), with higher SMI associated with higher FEV1% predicted.

CONCLUSIONS

Skeletal muscle index was low for men and women. We did not identify a significant relationship between pre-transplant thoracic SMI and post-transplant outcomes. There was an association between thoracic SMI and pre-transplant pulmonary function, confirming the potential value of sarcopenia as a marker of disease severity.

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.

Kidney Transplantation Outcome Predictions (KTOP): A Risk Prediction Tool for Kidney Transplants from Brain-dead Deceased Donors Based on a Large European Cohort

BACKGROUND

European kidney donation shortages mandate efficient organ allocation by optimizing the prediction of success for individual recipients.

OBJECTIVE

To develop the first European online risk tool for kidney transplant outcomes on the basis of recipient-only and recipient plus donor characteristics.

DESIGN, SETTING, AND PARTICIPANTS

We used individual recipient and donor risk factors and three outcomes (death, death with functioning graft [DWFG], and graft loss) for 32 958 transplants within the Eurotransplant kidney allocation system and the Eurotransplant senior program between January 2006 and May 2018 in eight European countries to develop and validate a risk tool.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cox proportional-hazards models were used to analyze the association of risk factors with overall patient mortality, and proportional subdistribution hazard regression models for their association with graft loss and DWFG. Prediction models were developed with recipient-only and recipient-donor risk factors. Sensitivity analyses based on time-specific area under the receiver operating characteristic curve (AUC) with leave-one-country-out validation were performed and calibration plots were generated.

RESULTS AND LIMITATIONS

The 10-yr cumulative incidence rate was 37% for mortality, 12% for DWFG, and 41% for graft loss. In recipient-donor models the leading risk factors for mortality were recipient diabetes (hazard ratio [HR] 10.73), retransplantation (HR 3.08 per transplant), and recipient age (HR 1.08). Effects were similar for DWFG. For graft loss, diabetes (subdistributional HR [SHR] 1.32), increased donor age (SHR 1.02), and prolonged cold ischemia time (SHR 1.02) had increased SHRs. All p values were <0.001.

CONCLUSIONS

Previously identified risk factors for outcomes following kidney transplants allow for outcome prediction with 10-yr AUC values of up to 0.81.

PATIENT SUMMARY

Using European data, we estimated individual risks to predict the success of kidney transplants and support physicians in decision-making. An online tool is now available (https://riskcalc.org/ktop/) for predicting kidney transplant outcomes both before and after a donor has been identified.

Predicting the risk of a clinical event using longitudinal data: the generalized landmark analysis

BACKGROUND

In the development of prediction models for a clinical event, it is common to use the static prediction modeling (SPM), a regression model that relates baseline predictors to the time to event. In many situations, the data used in training and validation are from longitudinal studies, where predictor variables are time-varying and measured at clinical visits. But these data are not used in SPM. The landmark analysis (LA), previously proposed for dynamic prediction with longitudinal data, has interpretational difficulty when the baseline is not a risk-changing clinical milestone, as is often the case in observational studies of chronic disease without intervention.

METHODS

This paper studies the generalized landmark analysis (GLA), a statistical framework to develop prediction models for longitudinal data. The GLA includes the LA as a special case, and generalizes it to situations where the baseline is not a risk-changing clinical milestone with a more useful interpretation. Unlike the LA, the landmark variable does not have to be time since baseline in the GLA, but can be any time-varying prognostic variable. The GLA can also be viewed as a longitudinal generalization of localized prediction, which has been studied in the context of low-dimensional cross-sectional data. We studied the GLA using data from the Chronic Renal Insufficiency Cohort (CRIC) Study and the Wisconsin Allograft Replacement Database (WisARD) and compared the prediction performance of SPM and GLA.

RESULTS

In various validation populations from longitudinal data, the GLA generally had similarly or better predictive performance than SPM, with notable improvement being seen when the validation population deviated from the baseline population. The GLA also demonstrated similar or better predictive performance than LA, due to its more general model specification.

CONCLUSIONS

GLA is a generalization of the LA such that the landmark variable does not have to be the time since baseline. It has better interpretation when the baseline is not a risk-changing clinical milestone. The GLA is more adaptive to the validation population than SPM and is more flexible than LA, which may help produce more accurate prediction.

Prevalence of frailty among patients with inflammatory bowel disease and its association with clinical outcomes: a systematic review and meta-analysis

BACKGROUND

Studies have reported frailty as an independent risk factor of mortality in patients with inflammatory bowel disease (IBD). However, no systematic review and meta-analysis has been conducted to determine the relationship of frailty and IBD. We aimed to investigate the prevalence of frailty in patients with IBD and the impact of frailty on the clinical prognosis of these patients.

METHODS

We systematically searched PubMed, Ovid (Medline), Embase, Web of Science, and Cochrane Library from database inception until October 2022. This systematic review included observational studies describing IBD and frailty. We performed meta-analysis for the frailty prevalence in patients with IBD. We analyzed primary outcomes (mortality) and secondary outcomes (infections, hospitalizations, readmission, and IBD-related surgery).

RESULTS

Nine studies with a total of 1,495,695 participants were included in our meta-analysis. The prevalence of frailty was 18% in patients with IBD. The combined effect analysis showed that frail patients with IBD had a higher risk of mortality (adjusted hazard ratio = 2.25, 95% confidence interval: 1.11-4.55) than non-frail patients with IBD. The hazard ratio for infections (HR = 1.23, 0.94-1.60), hospitalizations (HR = 1.72, 0.88-3.36), readmission (HR = 1.21, 1.17-1.25) and IBD-related surgery (HR = 0.78, 0.66-0.91) in frail patients with IBD.

CONCLUSIONS

We demonstrated that frailty is a significant independent predictor of mortality in patients with IBD. Our work supports the importance of implementing frailty screening upon admission in patients with IBD. More prospective studies are needed to investigate the influence of frailty on patients with IBD and improve the poor prognosis of patients with frailty and IBD.

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.

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.

Frailty in kidney transplantation: a review on its evaluation, variation and long-term impact

The problem of frailty in kidney transplantation is an increasingly discussed topic in the transplant field, partially also generated by the multiple comorbidities by which these patients are affected. The criteria currently used to establish the presence and degree of frailty can be rapidly assessed in clinical practice, even in patients with chronic kidney disease (CKD). The main objectives of this work are: (i) to describe the method of evaluation and the impact that frailty has in patients affected by CKD, (ii) to explore how frailty should be studied in the pre-transplant evaluation, (iii) how frailty changes after a transplant and (iv) the impact frailty has over the long term on the survival of renal transplant patients.

Patient Perspectives on the Use of Frailty, Cognitive Function, and Age in Kidney Transplant Evaluation

BACKGROUND

The allocation of scarce deceased donor kidneys is a complex process. Transplant providers are increasingly relying on constructs such as frailty and cognitive function to guide kidney transplant (KT) candidate selection. Patient views of the ethical issues surrounding the use of such constructs are unclear. We sought to assess KT candidates' attitudes and beliefs about the use of frailty and cognitive function to guide waitlist selection.

METHODS

KT candidates were randomly recruited from an ongoing single-center cohort study of frailty and cognitive function. Semi-structured interviews were conducted, and thematic analysis was performed. Inductively derived themes were mapped onto bioethics principles.

RESULTS

Twenty interviews were conducted (65% contact rate, 100% participation rate) (60% male; 70% White). With respect to the use of frailty and cognitive function in waitlisting decisions, four themes emerged in which participants: (1) valued maximizing a scarce resource (utility); (2) prioritized equal access to all patients (equity); (3) appreciated a proportional approach to the use of equity and utility (precautionary utility); and (4) sought to weigh utility- and equity-based concerns regarding social support. While some participants believed frailty and cognitive function were useful constructs to maximize utility, others believed their use would jeopardize equity. Patients were uncomfortable with using single factors such as frailty or cognitive impairment to deny someone access to transplantation; participants instead encouraged using the constructs to identify opportunities for intervention to improve frailty and cognitive function prior to KT.

CONCLUSIONS

KT candidates' values mirrored the current allocation strategy, seeking to balance equity and utility in a just manner, albeit with conflicting viewpoints on the appropriate use of frailty and cognitive impairment in waitlisting decisions.

Associations between frailty trajectories and cardiovascular, renal, and mortality outcomes in chronic kidney disease

BACKGROUND

Frailty is characterized by the loss of biological reserves and vulnerability to adverse outcomes. In individuals with chronic kidney disease (CKD), numerous pathophysiological factors may be responsible for frailty development including inflammation, physical inactivity, reduced energy intake, and metabolic acidosis. Given that both CKD and frailty incur a significant healthcare burden, it is important to understand the relationship of CKD and frailty in real-world routine clinical practice, and how simple frailty assessment methods (e.g. frailty indexes) may be useful. We investigated the risk of frailty development in CKD and the impact of frailty status on mortality and end-stage kidney disease (ESKD).

METHODS

A retrospective cohort study using primary care records from the Clinical Practice Research Datalink linked to Hospital Episode Statistics and the UK Office for National Statistics was undertaken in 819 893 participants aged ≥40 years, of which 140 674 had CKD. Frailty was defined using an electronic frailty index, generated electronically from primary care records. Cox proportional hazard and flexible parametric survival models were used to investigate the risk of developing frailty and the effect of frailty on risk of all-cause and cardiovascular mortality, and ESKD.

RESULTS

The mean age of those with CKD was 77.5 (SD 9.7) years [61.0 (SD 12.1) years in no-CKD group]; 62.0% of the CKD group were female (compared with 53.3% in no-CKD group). The mean estimated glomerular filtration rate of those with CKD was 46.1 (SD 9.9) mL/min/1.73 m² . The majority of those with CKD (75.3%) were frail [vs. 45.4% in those without CKD (no-CKD)]. Over 3 years (median), 69.5% of those with CKD developed frailty. Compared with no-CKD, those with CKD had increased rates of developing mild (hazard ratio: 1.02; 95% confidence interval: 1.01-1.04), moderate (1.30; 1.26-1.34), and severe (1.50; 1.37-1.65) frailty. Mild (1.22; 1.19-1.24), moderate (1.60; 1.56-1.63), and severe (2.16; 2.11-2.22) frailty was associated with increased rates of all-cause and cardiovascular-related mortality (mild 1.35; 1.31-1.39; moderate 1.96; 1.90-2.02; and severe 2.91; 2.81-3.02). All stages of frailty significantly increased ESKD rates.

CONCLUSIONS

Frailty is highly prevalent and associated with adverse outcomes in people with CKD, including mortality and risk of ESKD. Preventative interventions should be initiated to mitigate the development of frailty. The use of a simple frailty index, generated electronically from health records, can predict outcomes and may aid prioritization for management of people with frailty.

The Impact of Frailty on All-Cause Mortality in Patients with HIV Infection: A Systematic Review and Meta-Analysis

The aim of this study was to conduct a systematic review and meta-analysis of cohort studies that have examined the association between frailty and all-cause mortality in patients with HIV infection. We searched Embase, Medline through the Ovid interface, PubMed, Cochrane Library, and Web of Science to identify potential studies. Cohort studies of death outcomes in HIV patients under debilitating conditions were included and other ineligible or inadequate data were excluded. Data related to all-cause mortality in patients with HIV were extracted. The quality of the included studies was assessed using the Newcastle-Ottawa Scale for cohort studies. Hazard ratios (HRs) and their 95% confidence intervals (CIs) were pooled to estimate the association between frailty and all-cause mortality using Stata, version 12.0. We identified 845 unduplicated citations. Of these, six cohort studies were eligible for inclusion in the review after applying our inclusion and exclusion criteria. Pooled results demonstrated that patients with HIV experiencing frailty were at an increased risk of all-cause mortality (pooled HR = 2.69, 95% CI = 1.83-3.97, p < .001) compared with those without frailty. Frailty was significantly associated with an increased risk of all-cause mortality among patients with HIV, indicating that frailty is an important predictor of adverse clinical outcomes. Therefore, more attention should be paid to screen patients with HIV for frailty and adopt appropriate interventions and personalized treatment plans to prevent the occurrence of adverse events. However, these results need to be validated in further prospective cohort studies in ethnically or geographically diverse populations.

Frailty in end stage renal disease: Current perspectives

Frailty is common in end stage renal disease (ESRD) and is a marker of poor outcomes. Its prevalence increases as chronic kidney disease (CKD) progresses. There are different measurement tools available to assess frailty in ESRD. The pathogenesis of frailty in ESRD is multifactorial including uraemia and dialysis related factors. In this current review, we discuss the importance of frailty, its pathogenesis, screening methods, prognostic implications and management strategies in context of ESRD.

Increased mortality after kidney transplantation in mildly frail recipients

Background

Physical Frailty Phenotype (PFP) is the most used frailty instrument among kidney transplant recipients, classifying patients as pre-frail if they have 1–2 criteria and as frail if they have ≥3. However, different definitions of robustness have been used among renal patients, including only those who have 0 criteria, or those with 0–1 criteria. Our aim was to determine the impact of one PFP criterion on transplant outcomes.

Methods

We undertook a retrospective study of 296 kidney transplant recipients who had been evaluated for frailty by PFP at the time of evaluating for transplantation.

Results

Only 30.4% of patients had 0 criteria, and an additional 42.9% showed one PFP criterion. As PFP score increased, a higher percentage of women and cerebrovascular disease were found. Recipients with 0–1 criteria had lower 1-year mortality after transplant than those with ≥2 (1.8% vs 10.1%), but this difference was already present when we only considered those who scored 0 (mortality 1.1%) and 1 (mortality 2.4%) separately. The multivariable analysis confirmed that one PFP criterion was associated to a higher risk of patient death after kidney transplantation [hazard ratio 3.52 (95% confidence interval 1.03–15.9)].

Conclusions

Listed kidney transplant candidates frequently show only one PFP frailty criterion. This has an independent impact on patient survival after transplantation.

Inclusion of Exercise Prescription in Solid Organ Transplant in Physical Therapy Curricula Across Canadian Universities: A National Survey

Purpose : This study evaluated the extent of education about exercise prescription for patients with solid organ transplant (SOT) provided in physical therapy (PT) entry-level programmes across Canadian universities. The nature (content being taught), delivery (modes used to disseminate information), time dedicated to the topic, and opinions of educators were explored. Method : A cross-sectional survey was emailed to 36 educators at Canadian universities. The survey questions related to the nature, delivery, and time dedicated to SOT exercise prescription, and the opinions of educators. Results : The response rate was 93%. Educators reported that lung and heart transplantation were taught the most, followed by kidney and liver, with little to no emphasis on pancreas transplants. This material was mainly taught at the graduate level and as part of cardiopulmonary courses with minimal emphasis on practical skills. Aerobic exercise is the main exercise prescription being taught. The main barrier to offering more SOT prescription education experienced by educators was the lack of available class time. Conclusions : SOT exercise prescription is not extensively covered in PT curricula and does not include all organ groups to the same extent. Students have few practical opportunities, which are important to gain the abilities and confidence to treat this population. The development of a continuing education course could promote greater knowledge.

Kidney Transplantation After Rescue Allocation-the Eurotransplant Experience: A Retrospective Multicenter Outcome Analysis

BACKGROUND

At Eurotransplant (ET), kidneys are transferred to "rescue allocation" (RA), whenever the standard allocation (SA) algorithms Eurotransplant Kidney Allocation System (ETKAS) and Eurotransplant Senior Program (ESP) fail. We analyzed the outcome of RA.

METHODS

Retrospective patient clinical and demographic characteristics association analyses were performed with graft outcomes for 2422 recipients of a deceased donor renal transplantation (DDRT) after RA versus 25 481 after SA from 71 centers across all ET countries from 2006 to 2018.

RESULTS

Numbers of DDRTs after RA increased over the time, especially in Germany. RA played a minor role in ESP versus ETKAS (2.7% versus 10.4%). RA recipients and donors were older compared with SA recipients and donors, cold ischemia times were longer, waiting times were shorter, and the incidence of primary nonfunction was comparable. Among ETKAS recipients, HLA matching was more favorable in SA (mean 3.7 versus 2.5). In multivariate modeling, the incidence of graft loss in ETKAS recipients was reduced in RA compared with SA (subdistribution hazard ratio, 0.80; 95% confidence interval [0.70-0.91], P < 0.001), whereas other outcomes (mortality, death with functioning graft (DwFG)) were not significantly different. None of the 3 outcomes were significantly different when comparing RA with SA within the ESP program.

CONCLUSIONS

Facing increased waiting times and mortality on dialysis due to donor shortage, this study reveals encouragingly positive DDRT outcomes following RA. This supports the extension of RA to more patients and as an alternative tool to enable transplantation in patients in countries with prohibitively long waiting times or at risk of deterioration.

Distinct Phenotypes of Kidney Transplant Recipients in the United States with Limited Functional Status as Identified through Machine Learning Consensus Clustering

Background: There have been concerns regarding increased perioperative mortality, length of hospital stay, and rates of graft loss in kidney transplant recipients with functional limitations. The application of machine learning consensus clustering approach may provide a novel understanding of unique phenotypes of functionally limited kidney transplant recipients with distinct outcomes in order to identify strategies to improve outcomes. Methods: Consensus cluster analysis was performed based on recipient-, donor-, and transplant-related characteristics in 3205 functionally limited kidney transplant recipients (Karnofsky Performance Scale (KPS) < 40% at transplant) in the OPTN/UNOS database from 2010 to 2019. Each cluster’s key characteristics were identified using the standardized mean difference. Posttransplant outcomes, including death-censored graft failure, patient death, and acute allograft rejection were compared among the clusters Results: Consensus cluster analysis identified two distinct clusters that best represented the clinical characteristics of kidney transplant recipients with limited functional status prior to transplant. Cluster 1 patients were older in age and were more likely to receive deceased donor kidney transplant with a higher number of HLA mismatches. In contrast, cluster 2 patients were younger, had shorter dialysis duration, were more likely to be retransplants, and were more likely to receive living donor kidney transplants from HLA mismatched donors. As such, cluster 2 recipients had a higher PRA, less cold ischemia time, and lower proportion of machine-perfused kidneys. Despite having a low KPS, 5-year patient survival was 79.1 and 83.9% for clusters 1 and 2; 5-year death-censored graft survival was 86.9 and 91.9%. Cluster 1 had lower death-censored graft survival and patient survival but higher acute rejection, compared to cluster 2. Conclusion: Our study used an unsupervised machine learning approach to characterize kidney transplant recipients with limited functional status into two clinically distinct clusters with differing posttransplant outcomes.

Evolving Trends in Risk Profiles and Outcomes in Older Adults Undergoing Kidney Retransplantation

BACKGROUND

In older adults (≥65), access to and outcomes following kidney transplantation (KT) have improved over the past 3 decades. It is unknown if there were parallel trends in re-KT. We characterized the trends, changing landscape, and outcomes of re-KT in older adults.

METHODS

Among the 44,149 older kidney-only recipients (1995-2016) in the Scientific Registry of Transplant Recipients, we identified 1743 who underwent re-KT. We analyzed trends and outcomes (mortality, death-censored graft failure [DCGF]) by eras (1995-2002, 2003-2014, and 2015-2016) that were defined by changes to the expanded criteria donors and Kidney Donor Profile Index policies.

RESULTS

Among all older kidney-only recipients during 1995-2002, 2003-2014, 2015-2016 the proportion that were re-KTs increased from 2.7% to 4.2% to 5.7%, P < 0.001, respectively. Median age at re-KT (67-68-68, P = 0.04), years on dialysis after graft failure (1.4-1.5-2.2, P = 0.003), donor age (40.0-43.0-43.5, P = 0.04), proportion with panel reactive antibody 80-100 (22.0%-32.7%-48.7%, P < 0.001), and donation after circulatory death (1.1%-13.4%-19.5%, P < 0.001) have increased. Despite this, the 3-y cumulative incidence for mortality (22.3%-19.1%-11.5%, P = 0.002) and DCGF (13.3%-10.0%-5.1%, P = 0.01) decreased over time. Compared with deceased donor retransplant recipients during 1995-2002, those during 2003-2014 and 2015-2016 had lower mortality hazard (aHR = 0.78, 95% confidence interval, 0.63-0.86 and aHR = 0.55, 95% confidence interval, 0.35-0.86, respectively). These declines were noted but not significant for DCGF and in living donor re-KTs.

CONCLUSIONS

In older retransplant recipients, outcomes have improved significantly over time despite higher risk profiles; yet they represent a fraction of the KTs performed. Our results support increasing access to re-KT in older adults; however, approaches to guide the selection and management in those with graft failure need to be explored.

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.

Effects of Artificial Intelligence-Derived Body Composition on Kidney Graft and Patient Survival in the Eurotransplant Senior Program

The Eurotransplant Senior Program allocates kidneys to elderly transplant patients. The aim of this retrospective study is to investigate the use of computed tomography (CT) body composition using artificial intelligence (AI)-based tissue segmentation to predict patient and kidney transplant survival. Body composition at the third lumbar vertebra level was analyzed in 42 kidney transplant recipients. Cox regression analysis of 1-year, 3-year and 5-year patient survival, 1-year, 3-year and 5-year censored kidney transplant survival, and 1-year, 3-year and 5-year uncensored kidney transplant survival was performed. First, the body mass index (BMI), psoas muscle index (PMI), skeletal muscle index (SMI), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) served as independent variates. Second, the cut-off values for sarcopenia and obesity served as independent variates. The 1-year uncensored and censored kidney transplant survival was influenced by reduced PMI (p = 0.02 and p = 0.03, respectively) and reduced SMI (p = 0.01 and p = 0.03, respectively); 3-year uncensored kidney transplant survival was influenced by increased VAT (p = 0.04); and 3-year censored kidney transplant survival was influenced by reduced SMI (p = 0.05). Additionally, sarcopenia influenced 1-year uncensored kidney transplant survival (p = 0.05), whereas obesity influenced 3-year and 5-year uncensored kidney transplant survival. In summary, AI-based body composition analysis may aid in predicting short- and long-term kidney transplant survival.