Current status of the assessment of sarcopenia, frailty, physical performance and functional status in chronic kidney disease patients

Thresholds of handgrip strength for all-cause mortality in patients with chronic kidney disease: a secondary systematic review with dose-response meta-analysis

BACKGROUND

Although handgrip strength is associated with all-cause mortality in patients with chronic kidney disease (CKD), whether this relationship is dose-related is unknown. Therefore, we examined dose-response relationships between handgrip strength and all-cause mortality in CKD patients based on previous studies by meta-analysis.

METHODS

Data sources included three electronic databases (PubMed, Web of Science, and Embase) from inception through October 2023. The included cohort was a CKD population not limited to disease stage, and their handgrip strength was objectively measured. Two researchers independently screened studies, extracted data, and assessed the risk of bias. We utilized estimates of handgrip strength categories using robust-error meta-regression (REMR), pooled study-specific estimates, and established dose-response relationships. Outcomes of interest included only all-cause mortality.

RESULTS

A total of 18 studies with 4810 participants (aged 47-71 years) were included. REMR modeling showed a U-shaped trend of association between handgrip strength and all-cause mortality in patients with CKD. Higher handgrip strength values, from 10 kg to approximately 28 kg, were associated with lower mortality risk. After that, the risk of death increased slightly.

CONCLUSION

A U-shaped association exists between handgrip strength and all-cause mortality risk in CKD patients. Future studies with quantitative measurements for each CKD stage will help to determine precise relative risk estimates between handgrip strength and mortality risk in patients with different stages of CKD.

FRAIL scale as a screening tool and a predictor of mortality in non-dialysis dependent patients

BACKGROUND

This study aimed to compare the diagnostic yield of the FRAIL scale with respect to the physical frailty phenotype measure and their association with mortality in non-dialysis-dependent patients.

METHODS

In this prospective cohort study, non-dialysis dependent patients with chronic kidney disease (CKD) stages 3b-5 seen in the nephrology outpatient clinics of two university hospitals were included. The presence of frailty was evaluated by physical frailty phenotype measure and the FRAIL scale. Patients were evaluated for six months, and mortality was recorded. The Kappa test was used to evaluate the diagnostic properties between the methods, and logistic regression to test the association between frailty and mortality.

RESULTS

One hundred fifty-three patients were evaluated; average age was 65 (56-70) years, 50.9% were women, and the all-cause mortality rate was 2.6%. Forty-six patients were classified as living with frailty according to the physical frailty phenotype while 36 patients were rated frail by the FRAIL scale. In adults < 60 years of age, the FRAIL scale showed good accuracy (84.9%) and specificity (93.2%) but had low sensitivity (41.3%) and moderate agreement (Kappa = 0.41; p < 0.001) compared to the definition of the physical frailty phenotype. The adjusted logistic regression model showed that the patients with frailty assessed by the FRAIL scale had a greater chance of mortality than the non-frail patients (OR: 6.8; CI95%:1.477-31.513; p = 0.014).

CONCLUSION

Physical frailty phenotype identifies more patients as having pre-frailty and frailty in non-dialysis dependent patients as compared to the FRAIL scale. However, the FRAIL scale is a simple bedside tool that can be useful for screening for frailty and whose results were associated with mortality.

Phosphate is associated with frailty in older patients with chronic kidney disease not on dialysis

PURPOSE

Frailty is common in older patients with chronic kidney disease (CKD) and has been considered an independent risk factor for adverse clinical outcomes in this population. CKD-associated mineral and bone metabolism (CKD-MBD) increases energy expenditure and causes malnutrition and inflammation leading to frailty. We investigated whether CKD-MBD markers and energy metabolism are associated with frailty in patients with advanced CKD on conservative management.

METHODS

In this cross-sectional study, we investigated factors associated with frailty in a sample of 75 patients ≥ 65 years, with stage 4 or 5 CKD. Collected data included age, sex, body mass index, physical activity status, educational level, Charlson Comorbidity Index, and laboratory markers. Frailty was evaluated according to Fried's classification.

RESULTS

Frailty was observed in 51.3% and pre-frailty in 47.3%. The frail population was significantly older, with a high proportion of females, more inactive, had lower educational levels, spent a long time sitting throughout the day, and had higher phosphate and fibroblast growth factor 21 (FGF-21). In the multivariate logistic analysis age (odds ratio 1.13, p = 0.026) and phosphate (odds ratio 3.38, p = 0.021) remained independently associated with frailty.

CONCLUSION

Serum phosphate seems to be a toxin associated with the frailty phenotype in older patients with CKD. Whether strategies to decrease serum phosphate would reduce the risk of frailty in this population deserves further evaluation.

Molecular mechanism of Shengyang Yiwei Decoction in treating chronic kidney disease based on network pharmacology

There is a serious worldwide health problem caused by chronic kidney disease (CKD), yet there are few viable therapies. Therapeutic promise in the treatment of chronic kidney disease (CKD) has been shown by the use of the traditional Chinese herbal compound Shengyang Yiwei Decoction (SYD). However, the chemical processes through which SYD exerts its effects are still unknown. The purpose of this network pharmacology research is to better understand the molecular mechanism of action of Shengyang Yiwei Decoction (SYD) in the treatment of chronic kidney disease (CKD). Traditional Chinese Medicine Systems Pharmacology (TCMSP) was first searched for information on the chemical components of Shengyang Yiwei Decoction. The molecular targets of SYD were then predicted using the Pharm Mapper service. After that, we used databases like DIG-SEE, TTD, and OMIM to zero down on the targets most closely linked to CKD. Cytoscape 3.2.1 was used to generate the component-target network representing SYD's therapy of CKD. In addition, KEGG signal pathways and GO biological processes were analyzed using the DAVID database, and the findings were displayed via OmicShare Tools. Twenty-two active components were isolated from Shengyang Yiwei Decoction, and they were linked to 36 therapeutic targets for CKD in the current investigation. According to the results of the network pharmacology study, 41 signaling pathways are involved in mediating the therapeutic effects of SYD. In addition, SYD's broad therapeutic impact in CKD therapy was shown to include 29 molecular activities, 14 cell components, and 91 biological processes. This research utilizes a multivariate analysis to provide light on the strategies and outcomes of treating CKD using Shengyang Yiwei Decoction. Clinical therapeutic methods for CKD management may benefit greatly from a thorough knowledge of the underlying processes and material foundation of this disease.

Prevalence of physical frailty and impact on survival in patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Frailty is common in chronic kidney disease (CKD) patients and becomes more prevalent as kidney disease progresses. This study aimed to investigate the prevalence of physical frailty and quantify the relationship between frailty and mortality risk in patients with CKD.

METHODS

PubMed, Web of Science, Embase, Cochrane Central Register of Controlled Trials, Clinicaltrial.gov, and major renal academic conferences were systematically searched, and additional references to relevant articles were manually searched. The prevalence of physical frailty and the risk of mortality based on random-effects models were assessed using percentages and hazard ratio (HR) with a 95% confidence interval (CI).

RESULTS

A total of 139 articles, including 1,675,482 participants, met the eligibility criteria for the meta-analysis. The results showed that 34.5% (95% CI 31.0 to 38.1%) of CKD patients showed signs of frailty, and 39.4% (95% CI 35.4 to 43.5%) had prefrail symptoms. Compared to non-frail patients, the risk of mortality was increased by 94.1% (95% CI 1.586 to 2.375) in frail patients and 34.5% (95% CI 1.231 to 1.469) in prefrail patients.

CONCLUSION

The high prevalence of frailty and prefrail in adults with CKD and resulting in premature death emphasize the importance of measuring frailty, which provides important prognostic information and may provide opportunities for interventions to improve the prognosis of patients with CKD.

Pharmacokinetics of Antibacterial Agents in the Elderly: The Body of Evidence

Infections are important factors contributing to the morbidity and mortality among elderly patients. High rates of consumption of antimicrobial agents by the elderly may result in increased risk of toxic reactions, deteriorating functions of various organs and systems and leading to the prolongation of hospital stay, admission to the intensive care unit, disability, and lethal outcome. Both safety and efficacy of antibiotics are determined by the values of their plasma concentrations, widely affected by physiologic and pathologic age-related changes specific for the elderly population. Drug absorption, distribution, metabolism, and excretion are altered in different extents depending on functional and morphological changes in the cardiovascular system, gastrointestinal tract, liver, and kidneys. Water and fat content, skeletal muscle mass, nutritional status, use of concomitant drugs are other determinants of pharmacokinetics changes observed in the elderly. The choice of a proper dosing regimen is essential to provide effective and safe antibiotic therapy in terms of attainment of certain pharmacodynamic targets. The objective of this review is to perform a structure of evidence on the age-related changes contributing to the alteration of pharmacokinetic parameters in the elderly.

Indoxyl sulfate mediates low handgrip strength and is predictive of high hospitalization rates in patients with end-stage renal disease

Background and aims

Sarcopenia has a higher occurrence rate in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD) than in the general population. Low handgrip strength-and not sarcopenia per se-is associated with clinical outcomes in patients with CKD, including cardiovascular mortality and hospitalization. The factors contributing to low handgrip strength are still unknown. Accordingly, this study aimed to determine whether uremic toxins influence low handgrip strength in patients with CKD.

Materials and methods

This cohort study lasted from August 2018 to January 2020. The participants were divided into three groups: the control group [estimated glomerular filtration rate (eGFR) ≥ 60 ml/min], an advanced CKD group (eGFR = 15-60 ml/min), and an ESRD group (under maintenance renal replacement therapy). All participants underwent handgrip strength measurement, dual-energy X-ray absorptiometry, and blood sampling for myokines (irisin, myostatin, and interleukin 6) and indoxyl sulfate. Sarcopenia was defined according to the Asian Working Group for Sarcopenia consensus as low appendicular skeletal muscle index (appendicular skeletal muscle/height2 of < 7.0 kg/m2 in men and < 5.4 kg/m2 in women) and low handgrip strength (< 28 kg in men and < 18 kg in women).

Results

Among the study participants (control: n = 16; CKD: n = 17; and ESRD: n = 42), the ESRD group had the highest prevalence of low handgrip strength (41.6 vs. 25% and 5.85% in the control and CKD groups, respectively; p < 0.05). The sarcopenia rate was similar among the groups (12.5, 17.6, and 19.5% for the control, CKD, and ESRD groups, respectively; p = 0.864). Low handgrip strength was associated with high hospitalization rates within the total study population during the 600-day follow-up period (p = 0.02). The predictions for cardiovascular mortality and hospitalization were similar among patients with and without sarcopenia (p = 0.190 and p = 0.094). The serum concentrations of indoxyl sulfate were higher in the ESRD group (227.29 ± 92.65 μM vs. 41.97 ± 43.96 μM and 6.54 ± 3.45 μM for the CKD and control groups, respectively; p < 0.05). Myokine concentrations were similar among groups. Indoxyl sulfate was associated with low handgrip strength in univariate and multivariate logistic regression models [univariate odds ratio (OR): 3.485, 95% confidence interval (CI): 1.372-8.852, p = 0.001; multivariate OR: 8.525, 95% CI: 1.807-40.207, p = 0.007].

Conclusion

Handgrip strength was lower in the patients with ESRD, and low handgrip strength was predictive of hospitalization in the total study population. Indoxyl sulfate contributed to low handgrip strength and counteracted the benefits of myokines in patients with CKD.

Food-Derived Uremic Toxins in Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have a higher cardiovascular risk compared to the average population, and this is partially due to the plasma accumulation of solutes known as uremic toxins. The binding of some solutes to plasma proteins complicates their removal via conventional therapies, e.g., hemodialysis. Protein-bound uremic toxins originate either from endogenous production, diet, microbial metabolism, or the environment. Although the impact of diet on uremic toxicity in CKD is difficult to quantify, nutrient intake plays an important role. Indeed, most uremic toxins are gut-derived compounds. They include Maillard reaction products, hippurates, indoles, phenols, and polyamines, among others. In this review, we summarize the findings concerning foods and dietary components as sources of uremic toxins or their precursors. We then discuss their endogenous metabolism via human enzyme reactions or gut microbial fermentation. Lastly, we present potential dietary strategies found to be efficacious or promising in lowering uremic toxins plasma levels. Aligned with current nutritional guidelines for CKD, a low-protein diet with increased fiber consumption and limited processed foods seems to be an effective treatment against uremic toxins accumulation.

Angiotensin II type 1a receptor deficiency alleviates muscle atrophy after denervation

The study aim was to determine if suppressed activation of angiotensin II type 1 receptor (AT1) prevents severe muscle atrophy after denervation. The sciatic nerves in right and left inferior limbs were cut in AT1a knockout homo (AT1a^-/-) male mice and wild-type (AT1a^+/+) male mice. Muscle weight and cross-sectional areas of type IIb muscle fibers in gastrocnemius muscle decreased at 7 and 21 days postdenervation in both AT1a^-/- mice and AT1a^+/+ mice, and the reduction was significantly attenuated in the denervated muscles of AT1a^-/- mice compared to the AT1a^+/+ mice. Gene expressions in the protein degradation system [two E3 ubiquitin ligases (muscle RING-finger protein-1 and Atrogin-1)] upregulated at 7 days postdenervation in all denervated mice were significantly lower in AT1a^-/- mice than in AT1a^+/+ mice. Activations of nuclear factor κB and Forkhead box subgroup O1, and protein expression of monocyte chemoattractant protein-1 were significantly suppressed in the AT1a^-/- mice compared with those in the AT1a^+/+ mice. In addition, suppressed apoptosis, lower infiltration of M1 macrophages, and higher infiltration of M2 macrophages were significantly observed at 21 days postdenervation in the AT1a^-/- mice compared with those in the AT1a^+/+ mice. In conclusion, the AT1 receptor deficiency retarded muscle atrophy after denervation.

The "adult inactivity triad" in patients with chronic kidney disease: A review

Background

The "pediatric inactivity triad" framework consists of three complex, interrelated conditions influencing physical inactivity and associated health risks. Evidence on the beneficial effects of physical activity in adults with chronic kidney disease (CKD) continues to grow, but few studies have explored the complex interactions behind inactivity in this population.

Results

Based on the "pediatric inactivity triad" framework and prior research, we would like to propose a new concept, the "adult inactivity triad" in CKD, including (1) exercise deficit disorder, (2) sarcopenia, and (3) physical illiteracy. Individuals can shift from "adult inactivity triad" to "adult activity triad" and move at different rates and directions along the arrows in each of the three components.

Conclusion

This review explores and summarizes previous research on the three main adult inactivity triad components in the chronic kidney disease population.

Sarcopenia and sarcopenic obesity in chronic kidney disease: update on prevalence, outcomes, risk factors and nutrition treatment

PURPOSE OF REVIEW

This review summarizes literature from the last 18 months reporting on sarcopenia (or its components) in chronic kidney disease (CKD).

RECENT FINDINGS

The prevalence of sarcopenia in CKD is reported to be 5-62.5%, with higher rates observed later in the disease. Sarcopenic obesity rates are reported to be 2-23%. Sarcopenia in CKD is associated with increased risk of mortality, cardiovascular disease and vascular calcification. Risk factors include kidney disease itself and the impacts of CKD on lifestyle (reduced physical activity, diet changes). In earlier stages of CKD, if the risks from sarcopenia outweigh the risk of reaching end-stage renal disease, ensuring adequate energy intake combined with modest protein liberalization and physical activity may be indicated. Protein intakes above 1.3 g/kg of body weight per day should be avoided. For dialysis patients, interventions that provide a combination of carbohydrate, protein and fat appear more effective than those that provide protein alone, though it may take as long as 48 weeks for detectable changes in muscle mass.

SUMMARY

Sarcopenia is prevalent in CKD as kidney disease significantly impacts muscle mass and function. Nutrition interventions can improve components of sarcopenia, with an emphasis on adequate energy and protein.

Frailty, multimorbidity and sarcopaenia in haemodialysis patients

PURPOSE OF REVIEW

It is well recognised that haemodialysis patients have higher levels of multimorbidity, frailty and sarcopaenia. This review examines the current understanding of the three concepts in relation to the general population and haemodialysis patients, and the methods used to quantify them. It also looks at the interaction between multimorbidity, frailty and sarcopaenia in this patient group and proposes a new model that utilises muscle mass index and fat mass index as a surrogate representation of the three concepts.

RECENT FINDINGS

Multimorbidity in on the rise in the general population and this is one of the contributing factors to higher rates of chronic kidney disease, progression to end-stage renal disease and multimorbidity in haemodialysis patients. Malnutrition and haemodialysis induced end organ damage further contributes to muscle loss and frailty in this patient group. There is a significant overlap and interaction between multimorbidity, frailty and sarcopaenia in haemodialysis and their presence carries a significant impact on quality of life and survival. There are multiple scores for measuring multimorbidity, frailty and sarcopenia and there is no consensus on their utilisation in haemodialysis patients. We propose the use of fat mass index and muscle mass index model as a surrogate method for clinically quantifying multimorbidity, frailty and sarcopaenia.

SUMMARY

Effective public health policies are likely to have an impact on reducing the prevalence of multimorbidity and the development of end stage renal disease. Future research is required to develop interventions that are targeted at maintaining muscle mass and function in haemodialysis patients.

The Effect of Nutrition and Exercise on Body Composition, Exercise Capacity, and Physical Functioning in Advanced CKD Patients

Patients with stages 4 and 5 chronic kidney disease (CKD), and particularly chronic dialysis patients, commonly are found to have substantially reduced daily physical activity in comparison to age- and sex-matched normal adults. This reduction in physical activity is associated with a major decrease in physical exercise capacity and physical performance. The CKD patients are often physically deconditioned, and protein energy wasting (PEW) and frailty are commonly present. These disorders are of major concern because physical dysfunction, muscle atrophy, and reduced muscle strength are associated with poor quality of life and increased morbidity and mortality in CKD and chronic dialysis patients. Many randomized controlled clinical trials indicate that when CKD and chronic dialysis are provided nutritional supplements or undergo exercise training their skeletal muscle mass and exercise capacity often increase. It is not known whether the rise in skeletal muscle mass and exercise capacity associated with nutritional support or exercise training will reduce morbidity or mortality rates. A limitation of these clinical trials is that the sample sizes of the different treatment groups were small. The aim of this review is to discuss the effects of nutrition and exercise on body composition, exercise capacity, and physical functioning in advanced CKD patients.

Changes in renal function after nephroureterectomy for upper urinary tract carcinoma: analysis of a large multicenter cohort (Radical Nephroureterectomy Outcomes (RaNeO) Research Consortium)

PURPOSE

To investigate prevalence and predictors of renal function variation in a multicenter cohort treated with radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

METHODS

Patients from 17 tertiary centers were included. Renal function variation was evaluated at postoperative day (POD)-1, 6 and 12 months. Timepoints differences were Δ1 = POD-1 eGFR - baseline eGFR; Δ2 = 6 months eGFR - POD-1 eGFR; Δ3 = 12 months eGFR - 6 months eGFR. We defined POD-1 acute kidney injury (AKI) as an increase in serum creatinine by ≥ 0.3 mg/dl or a 1.5 1.9-fold from baseline. Additionally, a cutoff of 60 ml/min in eGFR was considered to define renal function decline at 6 and 12 months. Logistic regression (LR) and linear mixed (LM) models were used to evaluate the association between clinical factors and eGFR decline and their interaction with follow-up.

RESULTS

A total of 576 were included, of these 409(71.0%) and 403(70.0%) had an eGFR < 60 ml/min at 6 and 12 months, respectively, and 239(41.5%) developed POD-1 AKI. In multivariable LR analysis, age (Odds Ratio, OR 1.05, p < 0.001), male gender (OR 0.44, p = 0.003), POD-1 AKI (OR 2.88, p < 0.001) and preoperative eGFR < 60 ml/min (OR 7.58, p < 0.001) were predictors of renal function decline at 6 months. Age (OR 1.06, p < 0.001), coronary artery disease (OR 2.68, p = 0.007), POD-1 AKI (OR 1.83, p = 0.02), and preoperative eGFR < 60 ml/min (OR 7.80, p < 0.001) were predictors of renal function decline at 12 months. In LM models, age (p = 0.019), hydronephrosis (p < 0.001), POD-1 AKI (p < 0.001) and pT-stage (p = 0.001) influenced renal function variation (ß 9.2 ± 0.7, p < 0.001) during follow-up.

CONCLUSION

Age, preoperative eGFR and POD-1 AKI are independent predictors of 6 and 12 months renal function decline after RNU for UTUC.