Frailty in Kidney Disease: A Comprehensive Review to Advance Its Clinical and Research Applications. American journal of kidney diseases : the official journal of the National Kidney Foundation 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. 10.1053/j.ajkd.2024.04.018

Associations between frailty, genetic predisposition, and chronic kidney disease risk in middle-aged and older adults: A prospective cohort study. Maturitas OBJECTIVES:Cross-sectional evidence has shown that frailty is highly prevalent in patients with chronic kidney disease (CKD). However, there is limited evidence of the longitudinal associations between frailty, genetic predisposition to CKD, and the risk of CKD in the general population. Therefore, this study aimed to examine such associations among participants in the UK Biobank. STUDY DESIGN:This is a prospective cohort study included 370,965 middle-aged and older adults from the UK Biobank. Physical frailty was assessed using a modified version of the Fried phenotype classification. A weighted genetic risk score was built using 263 variants associated with estimated glomerular filtration rate. MAIN OUTCOME MEASURES:Incident CKD was identified from hospital inpatient records. RESULTS:Over a median follow-up of 12.3 years, we documented a total of 11,121 incident CKD cases. Time-dependent Cox proportional hazards regression models indicated that individuals with frailty (hazard ratio [HR]: 1.94, 95 % confidence interval [CI]: 1.81-2.08) and pre-frailty (HR: 1.27, 95 % CI: 1.22-1.33) had an increased risk of developing CKD, compared with non-frail individuals. No significant interaction between frailty and genetic risk score was observed (P for interaction = 0.41). The highest risk was observed among the individuals with high genetic risk and frailty (HR: 2.31, 95 % CI: 2.00-2.68). CONCLUSION:Our results demonstrated that frailty and pre-frailty were associated with increased risk of incident CKD in middle-age and older adults, regardless of genetic risk of CKD. Our study underscores the importance of frailty screening and intervention as a potential strategy to prevent CKD. Future clinical trials are needed to validate our findings. 10.1016/j.maturitas.2024.108059

The Impact of Frailty and Severe Cognitive Impairment on Survival Time and Time to Initiate Dialysis in Older Adults With Advanced Chronic Kidney Disease: A Prospective Observational Cohort Study. Cureus Background and objectives Frailty and cognitive impairment significantly impact survival time and time to initiate dialysis in older adults with advanced chronic kidney disease (CKD). This study aims to evaluate the effects of frailty and cognitive impairment on these outcomes and determine the most effective assessment tool for predicting early dialysis initiation and short survival time. Materials and methods This prospective observational cohort study involved 240 patients aged ≥65 years with stage 4 or 5 CKD, recruited from a nephrology outpatient department (ambulatory care) between March 2020 and March 2021. Frailty was assessed using the Physical Frailty Phenotype (PFP), PRISMA-7, Clinical Frailty Scale (CFS), and FRAIL scale. Cognitive function was evaluated using the Montreal Cognitive Assessment (MoCA). The primary outcomes were time to initiate dialysis and survival time, with secondary outcomes including hospitalization rates, length of stay, and mortality after dialysis initiation. Results Frail patients only showed significantly shorter time to dialysis initiation when identified by the PFP and FRAIL scale (28.3 months for frail vs. 31.2 months for non-frail, p = 0.028; 26.9 months for frail vs. 30.9 months for non-frail, p = 0.038). The PFP, FRAIL, and CFS tools indicated significantly shorter survival times for frail patients compared to non-frail patients (26.8 months for frail vs. 30.6 months for non-frail, p = 0.003). Frailty is strongly correlated with severe cognitive impairment, as 45.5% of frail patients (according to the FRAIL scale) have dementia compared to 15.1% of non-frail patients (p<0.001). However, cognitive impairment did not significantly affect the time to dialysis initiation or survival time. Hospitalization rates and length of stay in the hospital were significantly higher only for frail patients identified by PRISMA-7, with a median hospital length of stay of 9.15 days for frail patients vs 6.37 days for non-frail patients (p = 0.044). Overall, 37.5% of the patients did not survive during the study follow-up, with frail patients having a higher mortality rate. Conclusion Frailty, mainly when assessed by PFP and FRAIL, is a significant predictor of early dialysis initiation and reduced survival time in older adults with advanced CKD. Cognitive impairment, while prevalent, did not independently predict these outcomes. Regular frailty screening should be incorporated into CKD management to tailor interventions and improve patient outcomes. 10.7759/cureus.64303

Genetically predicted frailty index and risk of chronic kidney disease. Scientific reports Previous findings have reported the association between frailty and chronic kidney disease. However, the causality remains ambiguous. This study aimed to determine whether frailty index is causally associated with chronic kidney disease. We obtained the frailty genome-wide association study (GWAS) data and chronic kidney disease GWAS data from the FinnGen R5 (total n = 216,743; case = 3902, control = 212,841) as the exposure and outcome, respectively. A two-sample Mendelian randomization (MR) analysis was primarily conducted using the inverse-variance weighted (IVW), weighted median and MR-Egger regression analyses. Multivariable MR analysis (MVMR) was conducted for additional adjustment. In the two-sample Mendelian randomization analyses, a total of 14 single nucleotide polymorphisms (SNPs) were recognized as effective instrumental variables. The IVW method showed evidence to support a causal association between frailty index and chronic kidney disease (beta = 1.270; 95% CI 0.608 to 1.931; P < 0.001). MR-Egger revealed a causal association between frailty index and chronic kidney disease (beta = 3.612; 95% CI 0.805 to 6.419; P = 0.027). MR-Egger regression revealed that directional pleiotropy was unlikely to be biasing the result (intercept =  - 0.053; P = 0.119). The weighted median approach and weighted mode method also demonstrated a causal association between frailty index and chronic kidney disease (beta = 1.148; 95% CI 0.278 to 2.019; P = 0.011; beta = 2.194; 95% CI 0.598 to 3.790; P = 0.018). Cochran's Q test and the funnel plot indicated no directional pleiotropy. MVMR analysis revealed that the causal association between frailty index and chronic kidney disease remained after adjusting for potential confounders, body-mass index, inflammatory bowel disease, waist-hip ratio, and C-reactive protein. Our study provides evidence of causal association between frailty and chronic kidney disease from genetic perspectives. 10.1038/s41598-024-71881-7