Fatigue in CKD: Epidemiology, Pathophysiology, and Treatment

Skeletal muscle mass and kidney function among Chinese older adults: a cross-sectional study

OBJECTIVES

To assess the association between kidney function and odds of having low skeletal muscle mass (LSMM) in Chinese adults on the basis of a community study.

DATA AND METHODS

In this cross-sectional study, we included 3726 Chinese older persons who participated in an ongoing prospective study, the China Health and Retirement Longitudinal Study(CHARLS). Fasting blood samples were collected in 2012 and analyzed for serum creatinine. Estimated glomerular filtration rate(eGFR) was computed using serum creatinine, gender, and age, according to the 2021 race-free Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). We classified the target population into three categories according to eGFR (normal eGFR;90mL/min/1.73m2, mildly-impaired eGFR;60 to < 90 mL/min/1.73 m2, moderate to severve impaired eGFR;<60 mL/min/1.73 m2). BMI-adjusted muscle mass was used to measure skeletal muscle mass.The association between eGFR(per interquartile range(IQR) increment) and the risk of low skeletal muscle mass was assessed using logistic regression model.

RESULTS

Worsening renal function was associated with being high risk for LSMM after adjusting for potential confounders:the odds ratios (ORs) 95% confidence intervals (CIs) were 0.76 (95% CI = 0.63 - 0.88) for male, and [0.71, (0.61-0.82)]in female, p < 0.001. Specifically, male participants with mildly renal impairment were more prone to develop LSMM (multiadjusted OR, 1.43, 95% CI(0.92 to 2.09), p = 0.1) than femal(multiadjusted OR, 1.32, 95% CI(0.85 to 2.00), p = 0.2), the gender difference was not significant in severe renal dysfunction.However, there was a non-linear relationship between eGFR(per IQR increment) and risk of LSMM(eGFR/IQR =5.42, knot = 4 OR =1, p for non-linear <0.001).

CONCLUSIONS

Lower levels of eGFR had a high likelihood of being high risk for LSMM. Older male patients with mildly renal insufficiency are more likely to experience a decrease in skeletal muscle mass compared to female.

Dose-dependent association between estimated glomerular filtration rate and the subsequent risk of depression: An analysis of a nationwide epidemiological dataset

BACKGROUND

Although the risk of depression is well-known in the patients with kidney dysfunction, especially at the late stages, little is known about the exact point at which the decline in estimated glomerular filtration rate (eGFR) begins to significantly increase the risk of depression. In the present study, we analysed a nationwide epidemiological dataset to investigate the dose-dependent association between baseline eGFR and a future risk of developing depression in a general population.

METHODS

We retrospectively analysed 1,518,885 individuals (male: 46.3%) without a history of depression identified between April 2014 and November 2022 within a nationwide epidemiological database, provided by DeSC Healthcare (Tokyo, Japan). We investigated the association of eGFR with the incidence of depression using Cox regression analyses and also conducted cubic spline analysis to investigate the dose-dependent association between eGFR and depression.

RESULTS

In the mean follow-up of 1218 ± 693 days, 45,878 cases (3.0% for total participants, 2.6% for men and 3.3% for women) of depression were recorded. The risk of depression increased with the eGFR decline as well as the presence of proteinuria. Multivariable Cox regression analysis showed the hazard ratio (95% CI) of depression in each kidney function category (eGFR ≥90, 60-89, 45-59, 30-44, 15-29, and < 15 mL/min/1.73 m2) was 1.14 (1.11-1.17), 1 (reference), 1.11 (1.08-1.14), 1.51 (1.43-1.59), 1.77 (1.57-1.99) and 1.77 (1.26-2.50), respectively. In the cubic spline analysis, the risk of depression continued to increase monotonically as the eGFR declined when the eGFR fell below approximately 65 mL/min/1.73 m2.

CONCLUSIONS

Our analysis using a large-scale epidemiological dataset presented the dose-dependent association between eGFR decline and the risk of depression, which highlights the importance of incorporating mental health assessments into the routine care of patients with kidney dysfunction, regardless of the stage of their disease.

Does Physical Exercise Ameliorate Chronic Kidney Disease-Related Complications? The Case of Anaemia and Chronic Kidney Disease-Mineral Bone Disorder

BACKGROUND

Physical exercise (PE) can regulate inflammation, cardiovascular health, sarcopenia, anaemia, and bone health in the chronic kidney disease (CKD) population. Experimental and clinical studies both help us better understand the mechanisms that underlie the beneficial effects of the exercise, especially in renal anaemia and CKD-mineral bone disorders (CKD-MBDs). Here, we summarize this evidence, exploring the biological pathways involved, locally released substances, and crosstalk between tissues, but also the shortcomings of current knowledge.

SUMMARY

Anaemia: Both in healthy and CKD subjects, PE may mimic hypoxia, inhibiting PHDs; so hydroxylate HIF-α subunits may be translocated into the nucleus, resulting in dimerization of HIF-1α and HIF-1β, recruitment of p300 and CBP, and ultimately, binding to HREs at target genes to cause activation. However, in CKD subjects acute PE causes higher levels of lactate, leading to iron restriction by upregulating hepatic hepcidin expression, while chronic PE allows an increased lactate clearance and HIF-α and VEGFα levels, stimulating both erythropoiesis and angiogenesis.

CKD-MBD

PE may improve bone health decreasing bone resorption and increasing bone formation throughout at least three main pathways: (a) increasing osteoprotegerin and decreasing RANKL system; (b) decreasing cytokine levels; and (c) stimulating production of myokines and adipokines.

KEY MESSAGES

Future research needs to be defined to develop evidence-based exercise guidance to provide optimal benefit for CKD using exercise interventions as adjuvant therapy for CKD-related complications such as anaemia and CKD-MBD.

Early growth response protein 2 promotes partial epithelial-mesenchymal transition by phosphorylating Smad3 during renal fibrosis

Chronic kidney disease (CKD) is a serious health problem worldwide, which ultimately leads to end-stage renal disease (ESRD). Renal fibrosis is the common pathway and major pathological manifestation for various CKD proceeding to ESRD. However, the underlying mechanisms and effective therapies are still ambiguous. Early growth response 2 (EGR2) is reportedly involved in organ formation and cell differentiation. To determine the role of EGR2 in renal fibrosis, we respectively confirmed the increased expression of EGR2 in kidney specimens from both CKD patients and mice with location in proximal tubules. Genetic deletion of EGR2 attenuated obstructive nephropathy while EGR2 overexpression further promoted renal fibrosis in mice subjected to unilateral ureteral obstruction (UUO) due to extracellular matrix (ECM) deposition mediating by partial epithelial-mesenchymal transition (EMT) as well as imbalance between matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs (TIMPs). We found that EGR2 played a critical role in Smad3 phosphorylation, and inhibition of EGR2 reduced partial EMT leading to blockade of ECM accumulation in cultured human kidney 2 cells (HK2) treated with transforming growth factor β1 (TGF-β1). In addition, the transcription co-stimulator signal transducer and activator of transcription 3 (STAT3) phosphorylation was confirmed to regulate the transcription level of EGR2 in TGF-β1-induced HK2 cells. In conclusion, this study demonstrated that EGR2 played a pathogenic role in renal fibrosis by a p-STAT3-EGR2-p-Smad3 axis. Thus, targeting EGR2 could be a promising strategy for CKD treatment.

The impact of population ageing on the burden of chronic kidney disease

The burden of chronic kidney disease (CKD) and its risk factors are projected to rise in parallel with the rapidly ageing global population. By 2050, the prevalence of CKD category G3-G5 may exceed 10% in some regions, resulting in substantial health and economic burdens that will disproportionately affect lower-income countries. The extent to which the CKD epidemic can be mitigated depends largely on the uptake of prevention efforts to address modifiable risk factors, the implementation of cost-effective screening programmes for early detection of CKD in high-risk individuals and widespread access and affordability of new-generation kidney-protective drugs to prevent the development and delay the progression of CKD. Older patients require a multidisciplinary integrated approach to manage their multimorbidity, polypharmacy, high rates of adverse outcomes, mental health, fatigue and other age-related symptoms. In those who progress to kidney failure, comprehensive conservative management should be offered as a viable option during the shared decision-making process to collaboratively determine a treatment approach that respects the values and wishes of the patient. Interventions that maintain or improve quality of life, including pain management and palliative care services when appropriate, should also be made available.

Predictors of Fatigue Among Patients on Hemodialysis: An Observational Study

Background Hemodialysis is a chronic replacement therapy recommended during end-stage renal disease (ESRD) in chronic kidney disease (CKD). Post-dialysis fatigue (PDF) is one of the symptoms patients experience after the treatment. This multifactorial condition is subjective and characterized by a lack of physical and emotional energy. It can be associated with other symptoms such as nausea, headache, muscle cramps, and hypotension. Currently, researchers have not been able to find defined etiologies and pathogenesis. This study aims to analyze the influence of PDF predictors within a sample of patients undergoing hemodialysis. Methodology A multicenter, observational study was conducted on a convenience sample of 250 CKD patients with ESRD on hemodialysis between February and July 2023. PDF was assessed using the Piper Fatigue Scale (PFS), administered in both paper and electronic formats. The data analysis was done using descriptive and inferential statistics and correlation tests. Results The analysis revealed that sleep disorders perceived (p = 0.0001; τ = 0.23), the presence of comorbidity (p = 0.003; τ = 0.18), the number of weekly sessions (p = 0.012; τ = 0.15), and the period of hemodialysis (p = 0.0069; τ = 0.15) had a positive correlation with the PFS score. The study highlighted that hemoglobin level (p = 0.017; τ = - 0.14) and sex (p = 0.012; τ = 0.15) affected the PDF perception. Patients who engaged in physical activities or used distraction techniques (p = 1.83e-05; τ = 0.26) to alleviate PDF reported lower average scores on the PFS (2.27 points) compared to those who did not engage in any such activities. Conclusions Hemodialysis appears to be a source of stress for most patients, as they showed a moderate-to-severe score on the PFS scale. PDF is a multifactorial problem that must be recognized and treated properly by nurses through pharmacological therapies, as well as by educating and providing alternative strategies, that can contribute to alleviating the effects of fatigue.

Creatinine, cystatin C, muscle mass, and mortality: Findings from a primary and replication population-based cohort

BACKGROUND

Serum creatinine is used as initial test to derive eGFR and confirmatory testing with serum cystatin C is recommended when creatinine-based eGFR is considered less accurate due to deviant muscle mass. Low muscle mass is associated with increased risk of premature mortality. However, the associations of serum creatinine and cystatin C with muscle mass and mortality remain unclear and require further investigation to better inform clinical decision-making.

METHODS

We included 8437 community-dwelling adults enrolled in the Dutch PREVEND study and 5033 in the US NHANES replication cohort. Associations of serum creatinine and/or cystatin C with muscle mass surrogates and mortality were quantified with linear and Cox proportional hazards regression, respectively. Missing observations in covariates were multiply imputed using Substantive Model Compatible Fully Conditional Specification.

RESULTS

Mean (SD) age of PREVEND and NHANES participants (50% and 48% male) were 49.8 (12.6) and 48.7 (18.7) years, respectively. Median (Q1-Q3) serum creatinine and cystatin C were 71 (61-80) and 80 (62-88) μmol/L and 0.87 (0.78-0.98) and 0.91 (0.80-1.10) mg/L, respectively. Higher serum creatinine was associated with greater muscle mass, while serum cystatin C was not associated with muscle mass. Adjusting both markers for each other strengthened the positive relationship between serum creatinine and muscle mass and revealed an inverse association between serum cystatin C and muscle mass. In the PREVEND cohort, 1636 (19%) deaths were registered over a median follow-up of 12.9 (5.8-16.3) years with a 10-year mortality rate (95% CI) of 7.6% (7.1-8.2%). In the NHANES, 1273 (25%) deaths were registered over a median follow-up of 17.9 (17.3-18.5) years with a 10-year mortality rate of 13.8% (12.8-14.7%). Both markers were associated with increased mortality. Notably, when adjusted for each other, higher serum creatinine was associated with decreased mortality, while the association between serum cystatin C and increased mortality strengthened. The shapes of the associations in the PREVEND study and NHANES were almost identical.

CONCLUSIONS

The strong association between serum creatinine and muscle mass challenges its reliability as GFR marker, necessitating a more cautious approach in its clinical use. The minimal association between serum cystatin C and muscle mass supports its increased use as a more reliable alternative in routine clinical practice.

Prevalence and Risk Factors of Fatigue in Adults with Stage 3 and 4 CKD: Findings from the National Health and Nutrition Examination Survey, 2007-2012

Key Points

Fatigue is a common symptom experienced by adults with CKD. Physiological, sociodemographic, psychological, and behavioral factors are associated with fatigue.

Background

Fatigue is a devastating symptom experienced by adults with CKD, but less is known about the prevalence of fatigue and factors associated with fatigue in a general population of adults with CKD. Therefore, we examined the prevalence of fatigue and identified factors associated with fatigue among a national cohort of US adults with CKD.

Methods

We utilized cross-sectional data from 1079 adults from the National Health and Nutrition Examination Survey 2007–2012 and included participants aged 18 years and older with stage 3 and 4 CKD (eGFR between 15 and 60 ml/min per 1.73 m2) who had available data evaluating fatigue. Unadjusted and adjusted logistic regression models were used to evaluate the odds of having fatigue in the context of physiological, sociodemographic, psychological, and behavioral factors.

Results

We estimated that 48% of those with CKD had fatigue. Among the risk factors examined, those with the strongest evidence of association in multivariable analyses were female sex (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.02 to 2.17), pain (OR, 2.49; 95% CI, 1.57 to 3.93), poor mental health (OR, 1.97; 95% CI, 1.05 to 3.72), anxiety (OR, 1.95; 95% CI, 1.14 to 3.34), and depressive symptoms (OR, 2.58; 95% CI, 1.17 to 5.66).

Conclusions

Fatigue is a common symptom experienced by adults with CKD in the United States. Physiological, sociodemographic, psychological, and behavioral factors are associated with fatigue, with psychological factors being most strongly associated with fatigue. Future work is needed to identify interventions to mitigate fatigue and risk factors of fatigue in adults with CKD.

Experience of Chronic Kidney Disease and Perceptions of Transplantation by Sex

Importance

The pathway to kidney transplantation (KT) begins with the patient's acceptance of this surgical procedure after discussion with the nephrologist. The patients' perceptions of the disease and of KT may influence their willingness to undergo transplantation.

Objective

To describe patients' experiences of kidney disease and their perceptions of KT and the nephrologists' perceptions of the patient experience.

Design, Setting, and Participants

This qualitative study collected data through semistructured interviews with patients with chronic kidney disease and nephrologists in the Bretagne, Île-de-France and Normandie regions, France. Researchers involved in the study in each region purposely selected 99 patients with chronic kidney disease who initiated dialysis in 2021, based on their age, sex, dialysis facility ownership, and also 45 nephrologists, based on their sex and years of experience. Data analysis was performed from January to October 2023.

Main Outcomes and Measures

Themes were identified using inductive thematic analysis. Specific characteristics of men and women as well as the nephrologist's views for each theme were described.

Results

This study included 42 men and 57 women (56 [57%] aged 60 years or older) who started dialysis in 2021 and 45 nephrologists (23 women and 22 men). Six major themes were identified: (1) burden of chronic kidney disease on patients and their families, (2) health care professional-patient relationship and other factors that modulate chronic kidney disease acceptance, (3) dialysis perceived as a restrictive treatment, (4) patients' representation of the kidney graft, (5) role of past experiences in KT perception, and (6) dualistic perception of KT. In some cases, women and nephrologists indicated that women's perceptions and experiences were different than men's; for example, the disease's psychological impact and the living donor KT refusal were mainly reported by 8 women.

Conclusions and Relevance

Patients' past experience of chronic kidney disease in general and of KT in particular, as well as their relationship with their family and nephrologist, were substantial determinants of KT perception in this qualitative study. Targeted policies on these different factors might help to improve access to KT, and more research is needed to understand whether there are sex-based disparities.

Tyrosine phenol-lyase inhibitor quercetin reduces fecal phenol levels in mice

Tyrosine phenol-lyase (TPL), which is expressed in intestinal bacteria, catalyzes the formation of phenol from the substrate L-Tyr. Bacterial metabolite phenol and the sulfate conjugate (phenyl sulfate) are known as a type of uremic toxins, some of which exert cytotoxicity. Therefore, pathologically elevated phenol and phenyl sulfate levels are strongly implicated in the etiology and outcome of uremia. In this study, we explored the inhibitory effects of dietary polyphenols on TPL-catalyzed phenol production using a TPL activity assay. Quercetin, one of the most popular polyphenols, exhibited the strongest inhibitory activity (Ki = 19.9 µM). Quercetin competitively inhibited TPL, and its activity was stronger than that of a known TPL inhibitor (Tyr analog; 2-aza-Tyr, Ki = 42.0 µM). Additionally, quercetin significantly inhibited phenol production in TPL-expressing bacterial cultures (Morganella morganii and Citrobacter koseri) and Tyr-rich (5%) diet-fed C57BL/6J mouse feces. Our findings suggest that quercetin is the most promising polyphenol for reducing phenol levels. Because quercetin has a low gastrointestinal absorption rate, TPL inhibition in the intestinal tract by quercetin may be an effective strategy for treating uremia.

Indole Lactic Acid in Plasma and Urine: A Potential Biomarker for Chronic Kidney Disease and Inflammatory

Purpose

We aimed to explore changes in plasma and urine indole lactic acid (ILA) levels and the relationship between inflammation and ILA in chronic kidney disease (CKD) patients and healthy people.

Patients and Methods

Forty-seven CKD patients and 30 healthy individuals were included in this study. One-way ANOVA was used for variables with normal distribution and homogeneous variance. A rank-sum test was performed for non-normally distributed variables. Correlation analyses were performed using Pearson's or Spearman correlation analyses. Independent relationship between patients and CKD was analyzed using ordinal and binary logistic regressions. Receiver operating characteristic (ROC) curve was used.

Results

Plasma and urine ILA levels were positively correlated (r = 0.51, P < 0.01). Plasma ILA was positively correlated with BMI, age, creatinine, BUN, triglycerides, and uric acid and negatively correlated with hemoglobin levels. Urine ILA levels were positively correlated with age, creatinine, BUN, and uric acid and negatively correlated with hemoglobin and albumin levels. Ordered logistic regression analysis showed that CKD was significantly correlated with plasma ILA (OR=4.49, P < 0.01), urinary ILA (OR=2.14,P < 0.01), urea levels (OR=1.43, P < 0.01) and hemoglobin levels (OR=0.95, P < 0.01) were significantly related. ROC curves indicated that plasma and urinary ILA were reliable predictors of CKD. CKD was correlated with plasma, urine ILA (OR=5.92, P < 0.01; OR=2.79, P < 0.01) and Hs-CRP (OR=2.45, P < 0.01).

Conclusion

Plasma and urine ILA can potentially be used as biomarkers of CKD and inflammatory status.

Analysis of factors influencing the trajectory of fatigue in maintenance haemodialysis patients: a longitudinal study

OBJECTIVE

To explore the potential categories and influencing factors of fatigue trajectory in maintenance haemodialysis patients.

METHODS

Between June 2023 and December 2023, a convenience sample of 306 maintenance haemodialysis patients in a tertiary hospital haemodialysis centre in Zhenjiang City was selected as the study population, and patient information was collected monthly after the baseline survey using the General Information Questionnaire, Pittsburgh Sleep Quality Scale, Piper Fatigue Revision Scale, Collaborative Social Support Scale, Patient Health Questionnaire Depression Scale, Comprehensive Economic Toxicity Rating Scale, and Fear of Disease Progression Simplified Scale, for a total of six follow-up visits. In addition, the potential category growth model was used to identify the developmental trajectory of fatigue, and univariate analysis and binary logistic regression were used to analyse its determinants.

RESULTS

The 6 month fatigue trajectory of maintenance haemodialysis patients could be divided into two categories: persistent low-fatigue group (59.8%) and fluctuating high-fatigue group (40.2%). Age, surgical history, level of social support, sleep, economic toxicity, and changes in ultrafiltration volume during dialysis were the influencing factors for repeated fatigue in maintenance haemodialysis patients (p < 0.05).

CONCLUSION

The fatigue trajectory of maintenance haemodialysis patients is heterogeneous, suggesting that clinical workers should focus on the haemodialysis patients with repeated fatigue and make targeted interventions to improve their fatigue status and reduce the occurrence of adverse events in patients.

Association between higher intermuscular adipose tissue and decreased renal function in patients with systemic lupus erythematosus mediated by insulin resistance

OBJECTIVES

To quantify the relationship between abdominal computed tomography (CT)-based body composition parameters and renal function in systemic lupus erythematosus (SLE) patients and evaluate the potential effect of insulin resistance on this relationship.

METHODS

SLE patients from institutions A and B between January 2017 and August 2023 were enrolled. Areas and attenuation values of subcutaneous adipose tissue, visceral adipose tissue, intermuscular adipose tissue (IMAT), and skeletal muscle index on CT images were measured at the L3 vertebral level. Logistic regression analysis was used to identify risk factors associated with decreased renal function. Linear regression models were used to describe the relationships between body composition parameters and estimated glomerular filtration rate (eGFR). Finally, we used a single-point insulin sensitivity estimator to indirectly reflect the degree of insulin resistance and assess its mediating effect on the association between IMAT area and decreased renal function.

RESULTS

Three-hundred thirty-nine SLE patients from institution A (internal dataset) and 114 SLE patients from institution B (external validation dataset) were included. Multivariate logistic regression revealed that IMAT area (odds ratio (OR)institution A: 1.05 (95% confidence intervals (95% CI): 1.01, 1.10), and ORinstitution B: 1.19 (95% CI: 1.03, 1.39)) was an independent risk factor for decreased renal function in SLE patients. In the adjusted linear regression model, high IMAT area was significantly associated with reduced eGFR (βinstitution A = -1.15, Pinstitution A = 0.005; βinstitution B = -0.98, Pinstitution B = 0.049). Additionally, insulin resistance contributed a mediating role of 22.8% to the association.

CONCLUSION

High IMAT area was associated with decreased renal function in SLE patients and insulin resistance mediated this relationship.

CRITICAL RELEVANCE STATEMENT

High intermuscular adipose tissue area is associated with decreased renal function in systemic lupus erythematosus patients mediated by insulin resistance and is correlated with chronicity index in lupus nephritis patients.

KEY POINTS

High intramuscular adipose tissue (IMAT) area was associated with decreased renal function in systemic lupus erythematosus (SLE) patients. Insulin resistance mediated the association between IMAT area and eGFR. IMAT area was associated with chronicity index in lupus nephritis patients.

Symptom profiles in patients receiving maintenance hemodialysis and their association with quality of life: a longitudinal study

PURPOSE

Many patients receiving maintenance hemodialysis experience one or multiple symptoms. Using a latent profile analysis to identify symptom profiles may provide insights for person-centered symptom management strategies.

METHODS

This is a longitudinal study based on data from patients receiving maintenance hemodialysis at three hospitals in Shanghai, China. Of the 448 patients who completed the surveys at baseline (T1), 309 completed the 12-month follow-up survey (T2). Symptoms and quality of life were measured by the Chinese version of Kidney Disease Quality of Life 36 Short Form. The optimal classification of symptoms was identified using latent profile analysis.

RESULTS

Five symptom profiles were identified: High (9.2%), Fatigue and Gastrointestinal (7.1%), Fatigue and Skin (10.7%), Skin (23.2%), and Low (49.8%). The high-symptom profile and the-fatigue-and-skin-symptom profile were associated with a lower level of physical functioning, a higher burden of kidney disease, and more negative effects of kidney disease than the low symptom profile at T1 and T2. Multivariate regression analysis showed that the high-symptom profile predicted a poorer physical functioning at T2, and the-fatigue-and-skin-symptom profile predicted a poorer physical functioning and higher burden of kidney disease at T2.

CONCLUSION

Patients receiving maintenance hemodialysis reported unique symptom experiences which could be classified into different profiles. Patients reporting an overall high level of symptoms or a high level of fatigue and skin symptoms were more likely to have a poorer quality of life.

Fatigue by the Chalder Questionnaire and post-hemodialysis recovery in a population of predominantly African descent: The PROHEMO

BACKGROUND/OBJECTIVE

A high prevalence of fatigue and a positive association between fatigue and post-hemodialysis recovery have been reported in predominantly white populations of maintenance hemodialysis (MHD) patients. The present study evaluates associations between self-reported fatigue by the 11-item Chalder Fatigue Questionnaire (CFQ-11) and the need for post-hemodialysis recovery in a predominantly African-descent MHD population.

METHODS

A total of 233 patients (94% Black or Mixed-Race) participating in the "Prospective Study of the Prognosis of Patients on Maintenance Hemodialysis" (PROHEMO), Salvador, Brazil were recruited for this cross-sectional study. The CFQ-11 was used to measure fatigue: <4 for absent or mild, ⩾4 for moderate to severe. Patients were also asked if they needed some time to recover after the hemodialysis. Logistic regression was used to estimate odds ratio (OR) of the association with adjustments for age, sex, race, educational level, economic class level, diabetes, hearth failure, and hemoglobin.

RESULTS

Mean age was 51.5 ± 12.5 years. Moderate to severe fatigue (⩾4 points) was observed in 70.8% (165/233), and absent or mild fatigue (<4 points) in 29.2% (68/233). Compared to patients with fatigue scores <4 (20.6%), the need for post-hemodialysis recovery was 2.5 times greater in patients with fatigue scores ⩾4 (52.7%). The covariate-adjusted logistic regression OR was 4.60, 95% CI: 2.27, 9.21.

CONCLUSION

This study in MHD patients of predominantly African descent supports self-reported fatigue assessed by the CFQ-11 as a relevant predictor of the need for post-hemodialysis recovery. The results offer a rationale for investigating whether interventions to prevent fatigue reduce the need of post-hemodialysis recovery.

Effectiveness of Acupressure for Fatigue Alleviation in Patients Receiving Hemodialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Fatigue, a major health concern among patients receiving hemodialysis, is associated with poor quality of life, negative emotions, and cognitive dysfunction. Acupressure is a low-cost and noninvasive traditional Chinese therapy that has been widely used in community and clinic settings. However, the beneficial effects of acupressure on various aspects of fatigue among these patients have not been systematically investigated.

PURPOSE

This study was designed to determine the effects of acupressure on fatigue in patients receiving hemodialysis. The moderating influences of bio-sociodemographic characteristics and methodology on the association between acupressure and posthemodialysis fatigue were also examined.

METHODS

Four electronic databases were searched for qualified articles published between database inception and November 2, 2022. Only randomized controlled trials designed to investigate the effects of acupressure on fatigue in patients receiving hemodialysis were qualified for consideration. A random-effects model was used for data analysis.

RESULTS

Eight randomized controlled trials with 11 effect sizes and 725 participants were included in this study. In these studies, acupressure was found to have a significantly higher alleviation effect on general fatigue (g = -0.78; 95% confidence interval [-1.09, -0.48]) and the behavioral, emotional, sensory, and cognitive domains of fatigue (g = -0.51, -0.51, -0.72, and -0.41, respectively) among patients receiving hemodialysis than those in the control groups. Furthermore, the stimulation of the Shenmen acupoint was found to increase the effects (p < .01) of acupressure on fatigue reduction significantly. Notably, the use of special equipment to perform the acupressure was not found to significantly improve outcomes (p = .99).

CONCLUSIONS/IMPLICATIONS FOR PRACTICE

Acupressure is effective in alleviating fatigue in patients receiving hemodialysis, particularly when the Shenmen acupoint is used together with other acupoints, and is effective without the application of special equipment. Acupressure may be adopted as a complementary therapy for fatigue alleviation in patients receiving hemodialysis. Based on the findings, healthcare providers should coach patients receiving hemodialysis with fatigue on how to use acupressure therapy appropriately to alleviate this health concern.

Hemoglobin and Its Relationship with Fatigue in Long-COVID Patients Three to Six Months after SARS-CoV-2 Infection

Background: While some long-term effects of COVID-19 are respiratory in nature, a non-respiratory effect gaining attention has been a decline in hemoglobin, potentially mediated by inflammatory processes. In this study, we examined the correlations between hemoglobin levels and inflammatory biomarkers and evaluated the association between hemoglobin and fatigue in a cohort of Long-COVID patients. Methods: This prospective cohort study in the Netherlands evaluated 95 (mostly hospitalized) patients, aged 40-65 years, 3-6 months post SARS-CoV-2 infection, examining their venous hemoglobin concentration, anemia (hemoglobin < 7.5 mmol/L in women and <8.5 mmol/L in men), inflammatory blood biomarkers, average FSS (Fatigue Severity Score), demographics, and clinical features. Follow-up hemoglobin was compared against hemoglobin during acute infection. Spearman correlation was used for assessing the relationship between hemoglobin concentrations and inflammatory biomarkers, and the association between hemoglobin and fatigue was examined using logistic regression. Results: In total, 11 (16.4%) participants were suffering from anemia 3-6 months after SARS-CoV-2 infection. The mean hemoglobin value increased by 0.3 mmol/L 3-6 months after infection compared to the hemoglobin during the acute phase (p-value = 0.003). Whilst logistic regression showed that a 1 mmol/L greater increase in hemoglobin is related to a decrease in experiencing fatigue in Long-COVID patients (adjusted OR 0.38 [95%CI 0.13-1.09]), we observed no correlations between hemoglobin and any of the inflammatory biomarkers examined. Conclusion: Our results indicate that hemoglobin impairment might play a role in developing Long-COVID fatigue. Further investigation is necessary to identify the precise mechanism causing hemoglobin alteration in these patients.

Exploring the nexus between fatigue, body composition, and muscle strength in hemodialysis patients

BACKGROUND

Fatigue is a relatively prevalent condition among hemodialysis patients, resulting in diminished health-related quality of life and decreased survival rates. The purpose of this study was to investigate the relationship between fatigue and body composition in hemodialysis patients.

METHODS

This cross-sectional study included 92 patients in total. Fatigue was measured by Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F) (cut-off ≤ 34). Body composition was measured based on quantitative computed tomography (QCT), parameters including skeletal muscle index (SMI), intermuscular adipose tissue (IMAT), and bone mineral density (BMD). Handgrip strength was also collected. To explore the relationship between fatigue and body composition parameters, we conducted correlation analyses and binary logistic regression.

RESULTS

The prevalence of fatigue was 37% (n = 34), abnormal bone density was 43.4% (n = 40). There was a positive correlation between handgrip strength and FACIT-F score (r = 0.448, p < 0.001). Age (r = - 0.411, p < 0.001), IMAT % (r = - 0.424, p < 0.001), negatively associated with FACIT-F score. Multivariate logistic regression analysis shows that older age, lower serum phosphorus, higher IMAT% are associated with a high risk of fatigue.

CONCLUSION

The significantly increased incidence and degree of fatigue in hemodialysis patients is associated with more intermuscular adipose tissue in paraspinal muscle.

Core Patient-Reported Outcomes for Trials in Nephrology

The outcomes reported in trials across all stages of chronic kidney disease (CKD) are highly variable and often do not include outcomes that are directly relevant to patients and caregivers. Frequently, the outcomes reported in trials are often unvalidated surrogate biochemical end points. The omission of outcomes that are meaningful and important to patients can diminish the value of trials in supporting treatment decisions. In response, there have been increasing efforts across many health and medical disciplines to develop core outcome sets, defined as the minimum set of outcomes to be reported in all trials in a specific health area to improve the relevance and consistency of reporting trial outcomes. The international Standardized Outcomes in Nephrology (SONG) initiative was established in 2014 and has since developed seven core outcome sets for different diagnosis and treatment stages of CKD. The core outcomes were based on consensus among patients, caregivers, and health professionals. Each core outcome set includes at least one patient-reported outcome, including fatigue (hemodialysis), life participation (kidney transplantation, peritoneal dialysis, early CKD not yet requiring kidney replacement therapy, children and adolescents, and glomerular disease), and pain (polycystic kidney disease). This article outlines how patient-reported outcomes are currently reported in trials, discusses core patient-reported outcomes that have been established for trials in kidney disease, and outlines strategies for implementing core patient-reported outcomes in trials.

Why does malaise/fatigue occur? Underlying mechanisms and potential relevance to treatments in rheumatoid arthritis

INTRODUCTION

Fatigue and malaise are commonly associated with a wide range of medical conditions, including rheumatoid arthritis (RA). Evidence suggests that fatigue and malaise can be overwhelming for patients, yet these symptoms remain inadequately-managed, largely due to an incomplete elucidation of the underlying causes.

AREAS COVERED

In this assessment of the published literature relating to the pathogenesis of fatigue or malaise in chronic conditions, four key mechanistic themes were identified. Each theme (inflammation, hypothalamic-pituitary-adrenal axis, dysautonomia, and monoamines) is discussed, as well as the complex network of interconnections between themes which suggests a key role for inflammatory cytokines in the development and persistence of fatigue.

EXPERT OPINION

Fatigue is multifaceted, poorly defined, and imperfectly comprehended. Moreover, the cause and severity of fatigue may change over time, as a consequence of the natural disease course or pharmacologic treatment. This detailed synthesis of available evidence permits us to identify avenues for current treatment optimization and future research, to improve the management of fatigue and malaise in RA. Within the development pipeline, several new anti-inflammatory therapies are currently under investigation, and we anticipate that the next five years will herald much-needed progress to reduce the debilitating nature of fatigue in patients with RA.

The relationship between fatigue, pruritus, and thirst distress with quality of life among patients receiving hemodialysis: a mediator model to test concept of treatment adherence

Hemodialysis is a conservative treatment for end-stage renal disease. It has various complications which negatively affect quality of life (QOL). This study aimed to examine the relationship between fatigue, pruritus, and thirst distress (TD) with QOL of patients receiving hemodialysis, while also considering the mediating role of treatment adherence (TA). This cross-sectional study was carried out in 2023 on 411 patients receiving hemodialysis. Participants were consecutively recruited from several dialysis centers in Iran. Data were collected using a demographic information form, the Fatigue Assessment Scale, the Thirst Distress Scale, the Pruritus Severity Scale, the 12-Item Short Form Health Survey, and the modified version of the Greek Simplified Medication Adherence Questionnaire for Hemodialysis Patients. Covariance-based structural equation modeling was used for data analysis. The structural model and hypothesis testing results showed that all hypotheses were supported in this study. QOL had a significant inverse association with fatigue, pruritus, and TD and a significant positive association with TA. TA partially mediated the association of QOL with fatigue, pruritus, and TD, denoting that it helped counteract the negative association of these complications on QOL. This model explained 68.5% of the total variance of QOL. Fatigue, pruritus, and TD have a negative association with QOL among patients receiving hemodialysis, while TA reduces these negative associations. Therefore, TA is greatly important to manage the associations of these complications and improve patient outcomes. Healthcare providers need to assign high priority to TA improvement among these patients to reduce their fatigue, pruritus, and TD and improve their QOL. Further studies are necessary to determine the most effective strategies for improving TA and reducing the burden of complications in this patient population.

A tryptophan-derived uremic metabolite/Ahr/Pdk4 axis governs skeletal muscle mitochondrial energetics in chronic kidney disease

Chronic kidney disease (CKD) causes accumulation of uremic metabolites that negatively affect skeletal muscle. Tryptophan-derived uremic metabolites are agonists of the aryl hydrocarbon receptor (AHR), which has been shown to be activated in CKD. This study investigated the role of the AHR in skeletal muscle pathology of CKD. Compared with controls with normal kidney function, AHR-dependent gene expression (CYP1A1 and CYP1B1) was significantly upregulated in skeletal muscle of patients with CKD, and the magnitude of AHR activation was inversely correlated with mitochondrial respiration. In mice with CKD, muscle mitochondrial oxidative phosphorylation (OXPHOS) was markedly impaired and strongly correlated with the serum level of tryptophan-derived uremic metabolites and AHR activation. Muscle-specific deletion of the AHR substantially improved mitochondrial OXPHOS in male mice with the greatest uremic toxicity (CKD + probenecid) and abolished the relationship between uremic metabolites and OXPHOS. The uremic metabolite/AHR/mitochondrial axis in skeletal muscle was verified using muscle-specific AHR knockdown in C57BL/6J mice harboring a high-affinity AHR allele, as well as ectopic viral expression of constitutively active mutant AHR in mice with normal renal function. Notably, OXPHOS changes in AHRmKO mice were present only when mitochondria were fueled by carbohydrates. Further analyses revealed that AHR activation in mice led to significantly increased pyruvate dehydrogenase kinase 4 (Pdk4) expression and phosphorylation of pyruvate dehydrogenase enzyme. These findings establish a uremic metabolite/AHR/Pdk4 axis in skeletal muscle that governs mitochondrial deficits in carbohydrate oxidation during CKD.

Effect of Exercise on Fatigue in Patients Receiving Maintenance Hemodialysis Treatment: A Systematic Review and Network Meta-analysis

OBJECTIVE

This study aimed to evaluate the effect of different exercises for improving fatigue in maintenance hemodialysis patients.

DESIGN

PubMed, Embase, Web of Science, Cochrane, PEDro, CNKI, VIP, Wanfang data, CBM, and CINAHL were conducted from the establishment of the database to July 2023. We independently screened the literature, evaluated the quality, analyzed the data using Stata 15.0, and performed subgroup analysis on intervention time and exercise intervention adherence.

RESULTS

Twenty-three studies were analyzed, with 1867 patients and nine interventions. Based on the surface under cumulative ranking curves and pairwise comparisons effects, overall long-term, short-term, and exercise intervention adherence >90% effects have all presented that during dialysis aerobic-resistance combined exercise was ranked as the most effective compared with routine care (surface under cumulative ranking curves = 83.9%, standardized mean difference = -1.45, 95% CI = -2.23 to -0.67; surface under cumulative ranking curves = 85.9%, standardized mean difference = -1.38, 95% CI = -2.24 to -0.52; surface under cumulative ranking curves = 86.6%, standardized mean difference = -1.54, 95% CI = -2.58 to -0.49; surface under cumulative ranking curves = 83.6%, standardized mean difference = -1.45, 95% CI = -2.25 to -0.66, respectively), followed by interdialytic period muscle relaxation exercise, interdialytic period aerobic-resistance combined exercise, interdialytic period aerobic exercise, and interdialytic period Baduanjin.

CONCLUSIONS

Dialysis aerobic-resistance combined exercise may be considered in practice when resources allow. However, high-quality, multicenter, and large-sample randomized control trials must further verify this conclusion.

Iron dysregulation and inflammatory stress erythropoiesis associates with long-term outcome of COVID-19

Persistent symptoms following SARS-CoV-2 infection are increasingly reported, although the drivers of post-acute sequelae (PASC) of COVID-19 are unclear. Here we assessed 214 individuals infected with SARS-CoV-2, with varying disease severity, for one year from COVID-19 symptom onset to determine the early correlates of PASC. A multivariate signature detected beyond two weeks of disease, encompassing unresolving inflammation, anemia, low serum iron, altered iron-homeostasis gene expression and emerging stress erythropoiesis; differentiated those who reported PASC months later, irrespective of COVID-19 severity. A whole-blood heme-metabolism signature, enriched in hospitalized patients at month 1-3 post onset, coincided with pronounced iron-deficient reticulocytosis. Lymphopenia and low numbers of dendritic cells persisted in those with PASC, and single-cell analysis reported iron maldistribution, suggesting monocyte iron loading and increased iron demand in proliferating lymphocytes. Thus, defects in iron homeostasis, dysregulated erythropoiesis and immune dysfunction due to COVID-19 possibly contribute to inefficient oxygen transport, inflammatory disequilibrium and persisting symptomatology, and may be therapeutically tractable.

Exercise for patients with chronic kidney disease: from cells to systems to function

Chronic kidney disease (CKD) is among the leading causes of death and disability, affecting an estimated 800 million adults globally. The underlying pathophysiology of CKD is complex creating challenges to its management. Primary risk factors for the development and progression of CKD include diabetes mellitus, hypertension, age, obesity, diet, inflammation, and physical inactivity. The high prevalence of diabetes and hypertension in patients with CKD increases the risk for secondary consequences such as cardiovascular disease and peripheral neuropathy. Moreover, the increased prevalence of obesity and chronic levels of systemic inflammation in CKD have downstream effects on critical cellular functions regulating homeostasis. The combination of these factors results in the deterioration of health and functional capacity in those living with CKD. Exercise offers protective benefits for the maintenance of health and function with age, even in the presence of CKD. Despite accumulating data supporting the implementation of exercise for the promotion of health and function in patients with CKD, a thorough description of the responses and adaptations to exercise at the cellular, system, and whole body levels is currently lacking. Therefore, the purpose of this review is to provide an up-to-date comprehensive review of the effects of exercise training on vascular endothelial progenitor cells at the cellular level; cardiovascular, musculoskeletal, and neural factors at the system level; and physical function, frailty, and fatigability at the whole body level in patients with CKD.

Musculoskeletal Health Worsened from Carnitine Supplementation and Not Impacted by a Novel Individualized Treadmill Training Protocol

INTRODUCTION

Chronic kidney disease (CKD) negatively affects musculoskeletal health, leading to reduced mobility, and quality of life. In healthy populations, carnitine supplementation and aerobic exercise have been reported to improve musculoskeletal health. However, there are inconclusive results regarding their effectiveness and safety in CKD. We hypothesized that carnitine supplementation and individualized treadmill exercise would improve musculoskeletal health in CKD.

METHODS

We used a spontaneously progressive CKD rat model (Cy/+ rat) (n = 11-12/gr): (1) Cy/+ (CKD-Ctrl), (2) CKD-carnitine (CKD-Carn), and (3) CKD-treadmill (CKD-TM). Carnitine (250 mg/kg) was injected daily for 10 weeks. Rats in the treadmill group ran 4 days/week on a 5° incline for 10 weeks progressing from 30 min/day for week one to 40 min/day for week two to 50 min/day for the remaining 8 weeks. At 32 weeks of age, we assessed overall cardiopulmonary fitness, muscle function, bone histology and architecture, and kidney function. Data were analyzed by one-way ANOVA with Tukey's multiple comparisons tests.

RESULTS

Moderate to severe CKD was confirmed by biochemistries for blood urea nitrogen (mean 43 ± 5 mg/dL CKD-Ctrl), phosphorus (mean 8 ± 1 mg/dL CKD-Ctrl), parathyroid hormone (PTH; mean 625 ± 185 pg/mL CKD-Ctrl), and serum creatinine (mean 1.1 ± 0.2 mg/mL CKD-Ctrl). Carnitine worsened phosphorous (mean 11 ± 3 mg/dL CKD-Carn; p < 0.0001), PTH (mean 1,738 ± 1,233 pg/mL CKD-Carn; p < 0.0001), creatinine (mean 1 ± 0.3 mg/dL CKD-Carn; p < 0.0001), cortical bone thickness (mean 0.5 ± 0.1 mm CKD-Ctrl, 0.4 ± 0.1 mm CKD-Carn; p < 0.05). Treadmill running significantly improves maximal aerobic capacity when compared to CKD-Ctrl (mean 14 ± 2 min CKD-TM, 10 ± 2 min CKD-Ctrl; p < 0.01).

CONCLUSION

Carnitine supplementation worsened CKD progression, mineral metabolism biochemistries, and cortical porosity and did not have an impact on physical function. Individualized treadmill running improved maximal aerobic capacity but did not have an impact on CKD progression or bone properties. Future studies should seek to better understand carnitine doses in conditions of compromised renal function to prevent toxicity which may result from elevated carnitine levels and to optimize exercise prescriptions for musculoskeletal health.

A Current State of the Art and Science of Exercise in Dialysis: A Narrative Review

Purpose of the review

The purpose of the review is to discuss current proven benefits and problems of integrating exercise in the care of people receiving dialysis by reviewing literature from the last few years and identifying important questions that still need to be asked and answered.

Methods

A focused review and appraisal of the literature were done. Original peer-reviewed articles, review articles, opinion pieces and guidelines were identified from PubMed and Google Scholar databases. Only sources in English were accessed. Search terms "exercise" and "dialysis" were used to find active recruiting randomized trials in various clinical trial registry platforms.

Key findings

Numerous studies have demonstrated the benefits of exercise training in individuals receiving dialysis, limited by factors such as short duration of follow-up and inconsistent adverse event reporting and outcomes selected. Notable gaps in exercise research in dialysis include ways to maintain programs and patient motivation, studies in peritoneal dialysis and home hemodialysis patients, and how best to define and measure outcomes of interest.

Implications

This review summarizes the current state of exercise in people receiving dialysis and serves as a call to action to conduct large, randomized controlled trials to improve the quality of evidence needed to implement and sustain innovative, exercise interventions, and programs for this population.

Oral Nutritional Supplement Prescription and Patient-Reported Symptom Burden Among Patients With Late-Stage Non-Dialysis Chronic Kidney Disease

Background

Malnutrition and protein-energy wasting (PEW) are nutritional complications of advanced chronic kidney disease (CKD) that contribute to morbidity, mortality, and decreased quality of life. No previous studies have assessed the effect of oral nutritional supplements (ONSs) on patient-reported symptom burden among patients with non-dialysis CKD (CKD-ND) who have or are at risk of malnutrition/PEW.

Objective

The objective of this study was (1) to quantify the associations between baseline nutritional parameters and patient-reported symptom scores for wellbeing, tiredness, nausea, and appetite and (2) to compare the change in symptom scores among patients prescribed ONS with patients who did not receive ONS in a propensity-score-matched analysis.

Design

This study conducted observational cohort analysis using provincial registry data.

Setting

This study was done in multidisciplinary CKD clinics in British Columbia.

Patients

Adult patients >18 years of age with CKD-ND entering multidisciplinary CKD clinics between January 1, 2010-July 31, 2019 who had at least 2 Edmonton Symptom Assessment System Revised: Renal (ESASr:Renal) assessments.

Measurements

The measurements include nutrition-related parameters such as body mass index (BMI), serum albumin, serum phosphate, serum bicarbonate, neutrophil-to-lymphocyte ratio (NLR), and ESASr:Renal scores (overall and subscores for wellbeing, tiredness, nausea, and appetite).

Methods

Multivariable linear regression was applied to assess associations between nutritional parameters and ESASr:Renal scores. Propensity-score matching using the greedy method was used to match patients prescribed ONS with those not prescribed ONS using multiple demographic, comorbidity, health care utilization, and temporal factors. Linear regression was used to assess the association between first ONS prescription and change in ESASr:Renal overall score and subscores for wellbeing, tiredness, nausea, and appetite.

Results

Of total, 2076 patients were included. Higher baseline serum albumin was associated with lower overall ESASr:Renal score (-0.20, 95% confidence interval [CI] = -0.40 to -0.01 per 1 g/L increase in albumin), lower subscores for tiredness (-0.04, 95% CI = -0.07 to -0.01), nausea (-0.03, 95% CI = -0.04 to -0.01), and appetite (-0.03, 95% CI = -0.06 to -0.01). Higher BMI was associated with higher overall ESASr:Renal score (0.32, 95% CI = 0.16 to 0.48 per 1 kg/m2 increase in BMI), higher symptom subscores for wellbeing (0.02, 95% CI = 0.00 to 0.04) and tiredness (0.05, 95% CI = 0.02 to 0.07). Higher baseline NLR was associated with higher overall score (0.21, 95% CI = 0.03 to 0.39 per 1 unit increase in NLR), higher symptom subscores for wellbeing (0.03, 95% CI = 0.01 to 0.05) and nausea (0.03, 95% CI = 0.02 to 0.05). In the propensity-score-matched analysis, there were no statistically significant associations between ONS prescription and change in overall ESASr:Renal (beta coefficient for change in ESASr:Renal = 0.17, 95% CI = -2.64 to 2.99) or for subscores for appetite, tiredness, nausea, and wellbeing.

Limitations

Possible residual confounding. The ESASr:Renal assessments were obtained routinely only in patients with G5 CKD-ND and/or experiencing significant CKD-related symptoms.

Conclusions

This exploratory observational analysis of patients with advanced non-dialysis CKD demonstrated BMI, serum albumin, and NLR were modestly associated with patient-reported symptoms, but we did not observe an association between ONS use and change in ESASr:Renal scores.

Resistance exercise interventions for sarcopenia and nutritional status of maintenance hemodialysis patients: a meta-analysis

Background

A previous meta-analysis showed that exercise training improves patients' physical function and health status. However, the efficacy of resistance exercise (RE) in improving patients' physical function and nutritional status is uncertain.

Objective

To evaluate the effect of RE on sarcopenia and nutritional indicators in maintenance hemodialysis (MHD) patients.

Design

A meta-analysis.

Methods

Randomized controlled trials up to March 28, 2023 were searched from eight databases, including PubMed, Web of Science, Embase, Cochrane, China National Knowledge Infrastructure, Wan Fang, China Science and Technology Journal Database, and CBM. The risk of bias of the literature eligible for inclusion was assessed using the Cochrane risk-of-bias tool. When a high heterogeneity was detected, a random-effects model was used. Egger's tests were used to assess publication bias. This review was conducted in accordance with the PRISMA guidelines. The reliability of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation method, and a meta-analysis of the collected data was performed using Review Manager 5.4.1 software.

Results

Nine studies that met the criteria were identified, and 541 patients were included in these research.

Subjects

The results of this review showed that RE improved patients' grip strength levels (mean difference (MD) = 4.39, 95% confidence interval (CI) [3.14-5.64]; P < 0.00001), 6 min walking distance (MD = 40.71, 95% CI [8.92-72.49]; P = 0.01), muscle mass (MD = 4.50, 95% CI [2.01-6.99]; P = 0.0004), and serum albumin level (MD = 3.16, 95% CI [1.13-5.19]; P = 0.002) compared with the controls. However, the improvement caused by RE on hemoglobin (MD = 1.69, 95% CI [-1.49 to 4.87], P = 0.30) and cholesterol (MD = 2.33, 95% CI [-5.00 to 9.65], P = 0.53) levels was not statistically significant.

Conclusion

RE showed a significant effect on muscle function and strength of MHD patients. This meta-analysis provides new ideas on the efficacy of RE in muscle function and strength of MHD patients. The use of consistent RE patterns and nutritional interventions should be considered in future studies for further assessment of its effects. In the future, more high-quality studies will be required to verify these results.

Implications for practice

This meta-analysis identified the effect of RE on muscle strength, muscle function, and walking ability of HD patients, and provided a basis for clinical formulation of the optimal timing of intervention and the optimal frequency, intensity, modality, and content of intervention.

Patient or public contribution

No patient or public contribution because it does not apply to my work. This review has been registered at the International Platform of Registered Systematic Review and Meta-analysis (INPLASY) (registration number: INPLASY202340078).

Perceived Fatigability, Fatigue, and Mortality in Mid-to-Late Life in the Baltimore Longitudinal Study of Aging

INTRODUCTION/PURPOSE

Fatigue is an established prognostic indicator of mortality risk. It remains unknown whether fatigability anchored to a physical task is a more sensitive prognostic indicator and whether sensitivity differs by prevalent chronic conditions.

METHODS

A total of 1076 physically well-functioning participants 50 yr or older in the Baltimore Longitudinal Study of Aging self-reported fatigue (unusual tiredness or low energy) and had perceived fatigability assessed after a standardized treadmill walk. All-cause mortality was ascertained by proxy contact and National Death Index linkage. Cox proportional hazards models estimated associations of perceived fatigability and fatigue with all-cause mortality, adjusting for demographic and clinical covariates. Interactions by chronic conditions were also examined.

RESULTS

Each 1 SD higher in perceived fatigability, unusual tiredness, or low energy was associated with a higher relative hazard of all-cause mortality after covariate adjustment (fatigability: hazard ratio (HR), 1.18 (95% confidence interval (CI), 1.03-1.36); unusual tiredness: HR, 1.25 (95% CI, 1.08-1.44); low energy: HR, 1.27 (95% CI, 1.10-1.46)). Models had similar discrimination ( P > 0.14 for all). Perceived fatigability was associated with mortality risk among participants free of arthritis or osteoarthritis who otherwise appeared healthy (no arthritis: HR, 1.45 (95% CI, 1.15-1.84); arthritis: HR, 1.09 (95% CI, 0.92-1.30); P -interaction = 0.031). Unusual tiredness was associated with mortality among those with a history of diabetes (no diabetes: HR, 1.16 (95% CI, 0.97-1.38); diabetes: HR, 1.65 (95% CI, 1.22-2.23); P -interaction = 0.045) or pulmonary disease (no pulmonary disease: HR, 1.22 (95% CI, 1.05-1.43); pulmonary disease: HR, 2.15 (95% CI, 1.15-4.03); P -interaction = 0.034).

CONCLUSIONS

Higher perceived fatigability and fatigue symptoms were similarly associated with higher all-cause mortality, but utility differed by chronic condition. Perceived fatigability might be useful for health screening and long-term mortality risk assessment for well-functioning adults. Alternatively, self-reported fatigue seems more disease-specific with regard to mortality risk.

Impairments of functional exercise capacity, muscle strength, balance and kinesiophobia in patients with chronic kidney disease: a cross-sectional study

BACKGROUND

Muscle weakness, balance, and functional capacity are affected in patients with chronic kidney disease (CKD) in dialysis. However, studies about kinesiophobia, peripheral and respiratory muscle strength, balance, exercise capacity, fatigue, and physical activity level in patients with CKD 3-4 are limited. The study aimed to compare the functional exercise capacity, peripheral and respiratory muscle strength, pulmonary function, balance, kinesiophobia, physical activity, fatigue, and dyspnea between patients with CKD 3-4 and controls.

METHODS

This cross-sectional study included 43 patients and 45 controls. Functional exercise capacity [6-Minute Walking Test (6MWT)], peripheral and respiratory muscle strength, pulmonary function, dyspnea, fatigue, physical activity, balance [Berg Balance Scale (BBS)], and kinesiophobia were evaluated.

RESULTS

Demographic characteristics were similar in patients [53(50-57) y, 26 M/17F] and controls [51(4.506-55) y, 33 M/12F] (p > 0.05). The 6MWT, respiratory and peripheral muscle strength, pulmonary function, physical activity, and BBS were significantly lower, and the level of dyspnea and kinesiophobia were higher in patients compared with controls (p < 0.05).

CONCLUSIONS

Patients had impaired functional exercise capacity, upper and lower extremity muscle strength, respiratory muscle strength, pulmonary function, and balance, increased perception of dyspnea and kinesiophobia, and reduced physical activity level compared with controls. Patients should be directed to cardiopulmonary rehabilitation programs.

Evaluating the effect of a digital health intervention to enhance physical activity in people with chronic kidney disease (Kidney BEAM): a multicentre, randomised controlled trial in the UK

BACKGROUND

Remote digital health interventions to enhance physical activity provide a potential solution to improve the sedentary behaviour, physical inactivity, and poor health-related quality of life that are typical of chronic conditions, particularly for people with chronic kidney disease. However, there is a need for high-quality evidence to support implementation in clinical practice. The Kidney BEAM trial evaluated the clinical effect of a 12-week physical activity digital health intervention on health-related quality of life.

METHODS

In a single-blind, randomised controlled trial conducted at 11 centres in the UK, adult participants (aged ≥18 years) with chronic kidney disease were recruited and randomly assigned (1:1) to the Kidney BEAM physical activity digital health intervention or a waiting list control group. Randomisation was performed with a web-based system, in randomly permuted blocks of six. Outcome assessors were masked to treatment allocation. The primary outcome was the difference in the Kidney Disease Quality of Life Short Form version 1.3 Mental Component Summary (KDQoL-SF1.3 MCS) between baseline and 12 weeks. The trial was powered to detect a clinically meaningful difference of 3 arbitrary units (AU) in KDQoL-SF1.3 MCS. Outcomes were analysed by an intention-to-treat approach using an analysis of covariance model, with baseline measures and age as covariates. The trial was registered with ClinicalTrials.gov, NCT04872933.

FINDINGS

Between May 6, 2021, and Oct 30, 2022, 1102 individuals were assessed for eligibility, of whom 340 participants were enrolled and randomly assigned to the Kidney BEAM intervention group (n=173) or the waiting list control group (n=167). 268 participants completed the trial (112 in the Kidney BEAM group and 156 in the waiting list control group). All 340 randomly assigned participants were included in the intention-to treat population. At 12 weeks, there was a significant improvement in KDQoL-SF.13 MCS score in the Kidney BEAM group (from mean 44·6 AU [SD 10·8] at baseline to 47·0 AU [10·6] at 12 weeks) compared with the waiting list control group (from 46·1 AU [10·5] to 45·0 AU [10·1]; between-group difference of 3·1 AU [95% CI 1·8-4·4]; p<0·0001).

INTERPRETATION

The Kidney BEAM physical activity platform is an efficacious digital health intervention to improve mental health-related quality of life in patients with chronic kidney disease. These findings could facilitate the incorporation of remote digital health interventions into clinical practice and offer a potential intervention worthy of investigation in other chronic conditions.

FUNDING

Kidney Research UK.

Progress in the study of nutritional status and selenium in dialysis patients

Malnutrition is very common in patients with chronic kidney disease, especially in those on maintenance dialysis. Malnutrition is one of the major factors affecting survival and death of dialysis patients, and reducing their activity tolerance and immunity. There are numerous and interacting risk factors for malnutrition, such as reduced nutritional intake, increased energy expenditure, hormonal disorders, and inflammation. Selenium, in the form of selenoproteins, is involved in many physiological processes in the body and plays an important role in maintaining redox homeostasis. Oxidative stress and infection are very common in dialysis patients, and selenium levels in dialysis patients are significantly lower than those in the healthy population. It has been shown that there is a correlation between selenium levels in hemodialysis patients and their nutrition-related indicators, and that selenium supplementation may improve malnutrition in patients. However, further studies are needed to support this conclusion and there is a lack of basic research to further characterize the potential mechanisms by which selenium may improve malnutrition in dialysis patients. The purpose of this review is to provide a comprehensive overview of factors associated with malnutrition in dialysis patients and to describe the progress of research on nutritional status and selenium levels in dialysis patients.

The Effect of Listening to the Holy Qur'an and a Back Massage on Fatigue and Quality of Life for Participants Undergoing Hemodialysis: A Quasi-Experimental Study

This study examined the effects of combining listening to the Holy Qur'an and back massage on fatigue and the quality of life in participants undergoing hemodialysis in Indonesia. This nonrandomized clinical trial was conducted in 40 patients (n = 20 intervention group, n = 20 control group). The FACIT-fatigue scale was used to measure fatigue, and the KDQOL scale was used to measure quality of life. After the intervention, the mean score on the FACIT-fatigue scale in the intervention group was 36.7 ± 2.1, whereas it was 23.4 ± 5.8 in the control group. Likewise, while the average KDQOL score was 61.2 ± 5.8 in the intervention group, it was 49.5 ± 8.6 in the control group. In the between-group comparisons, fatigue score was significantly lower in the intervention group compared to the control group (p < 0.05), and the between-group comparison also demonstrated a significant difference favoring the intervention group. We conclude that the combination of listening to the Holy Qur'an and back massage improve participant's fatigue and quality of life.

Fatigue in Patients Receiving Maintenance Hemodialysis: A Review

Fatigue surrounding hemodialysis treatments is a common and often debilitating symptom that impacts patients' quality of life. Intradialytic fatigue develops or worsens immediately before hemodialysis and persists through the dialysis treatment. Little is known about associated risk factors or pathophysiology, although it may relate to a classic conditioning response. Postdialysis fatigue (PDF) develops or worsens after hemodialysis and may persist for hours. There is no consensus on how to measure PDF. Estimates for the prevalence of PDF range from 20%-86%, likely due to variation in methods of ascertainment and participant characteristics. Several hypotheses seek to explain the pathophysiology of PDF, including inflammation, hypothalamic-pituitary-adrenal axis dysregulation, and osmotic and fluid shifts, but none is currently supported by compelling or consistent data. PDF is associated with several clinical factors, including cardiovascular and hemodynamic effects of the dialysis procedure, laboratory abnormalities, depression, and physical inactivity. Clinical trials have reported hypothesis-generating data about the utility of cold dialysate, frequent dialysis, clearance of large middle molecules, treatment of depression, and exercise as potential treatments. Existing studies are often limited by sample size, lack of a control group, observational design, or short intervention duration. Robust studies are needed to establish the pathophysiology and management of this important symptom.

Lactate modulates iron metabolism by binding soluble adenylyl cyclase

Overproduction of lactate (LA) can occur during exercise and in many diseases such as cancers. Individuals with hyperlactatemia often display anemia, decreased serum iron, and elevated hepcidin, a key regulator of iron metabolism. However, it is unknown whether and how LA regulates hepcidin expression. Here, we show LA binds to soluble adenylyl cyclase (sAC) in normal hepatocytes and affects systemic iron homeostasis in mice by increasing hepcidin expression. Comprehensive in vitro, in vivo, and in silico experiments show that the LA-sAC interaction raises cyclic adenosine monophosphate (cAMP) levels, which activates the PKA-Smad1/5/8 signaling pathway to increase hepcidin transcription. We verified this regulatory axis in wild-type mice and in mice with disordered iron homeostasis. LA also regulates hepcidin in humans at rest and subjected to extensive exercise that produce elevated LA. Our study links hyperlactatemia to iron deficiency, offering a mechanistic explanation for anemias seen in athletes and patients with lactic acidosis.

Managing the symptom burden associated with maintenance dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Individuals with kidney failure undergoing maintenance dialysis frequently report a high symptom burden that can interfere with functioning and diminish life satisfaction. Until recently, the focus of nephrology care for dialysis patients has been related primarily to numerical targets for laboratory measures, and outcomes such as cardiovascular disease and mortality. Routine symptom assessment is not universal or standardized in dialysis care. Even when symptoms are identified, treatment options are limited and are initiated infrequently, in part because of a paucity of evidence in the dialysis population and the complexities of medication interactions in kidney failure. In May of 2022, Kidney Disease: Improving Global Outcomes (KDIGO) held a Controversies Conference-Symptom-Based Complications in Dialysis-to identify the optimal means for diagnosing and managing symptom-based complications in patients undergoing maintenance dialysis. Participants included patients, physicians, behavioral therapists, nurses, pharmacists, and clinical researchers. They outlined foundational principles and consensus points related to identifying and addressing symptoms experienced by patients undergoing dialysis and described gaps in the knowledge base and priorities for research. Healthcare delivery and education systems have a responsibility to provide individualized symptom assessment and management. Nephrology teams should take the lead in symptom management, although this does not necessarily mean taking ownership of all aspects of care. Even when options for clinical response are limited, clinicians should focus on acknowledging, prioritizing, and managing symptoms that are most important to individual patients. A recognized factor in the initiation and implementation of improvements in symptom assessment and management is that they will be based on locally existing needs and resources.

Assessing Fatigue in Patients Receiving Kidney Replacement Therapy Using PROMIS Computer Adaptive Testing

RATIONALE & OBJECTIVE

Fatigue is a debilitating symptom for many patients receiving kidney replacement therapy (KRT). Patient-reported outcome measures can help clinicians identify and manage fatigue efficiently. We assessed the measurement characteristics of the Patient Reported Outcome Measurement Information System (PROMIS)-Fatigue Computer Adaptive Test (PROMIS-F CAT) in patients receiving KRT using the previously validated Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

198 adults treated with dialysis or recipients of a kidney transplant in Toronto, Canada.

PREDICTORS

Demographic data, FACIT-F scores, KRT type.

OUTCOME

Measurement properties of PROMIS-F CAT T scores.

ANALYTICAL APPROACH

Reliability and test-retest reliability were assessed using standard errors of measurement and intraclass correlation coefficient (ICC), respectively. Construct validity was assessed using correlation and comparisons across predefined groups expected to have different levels of fatigue. Receiver operating characteristic (ROC) curves were used to assess the discrimination of PROMIS-F CAT, with clinically relevant fatigue defined by a FACIT-F score of≤30.

RESULTS

Of the 198 participants, 57% were male, the mean±SD age was 57±14 years; 65% had received a kidney transplant. Based on the FACIT-F score, 47 patients (24%) had clinically relevant fatigue. PROMIS-F CAT and FACIT-F were strongly correlated (ρ =-0.80, P<0.001). PROMIS-F CAT had excellent reliability (>0.90 for 98% of sample), and good test-retest reliability (ICC=0.85). The ROC analysis demonstrated outstanding discrimination (area under ROC=0.93 [95%, CI 0.89-0.97]). A PROMIS-F CAT cutoff score of≥59 accurately identified most patients with clinically relevant fatigue (sensitivity=0.83; specificity=0.91).

LIMITATIONS

A convenience sample of clinically stable patients. FACIT-F items are a part of the PROMIS-F item bank, although there was minimal overlap with only 4 FACIT-F items completed in PROMIS-F CAT.

CONCLUSIONS

PROMIS-F CAT has robust measurement properties with low question burden to assess fatigue among patients with KRT.

Sleep duration and cognitive function among older adults with chronic kidney disease: results from the National Health and Nutrition Examination Survey (2011-2014)

BACKGROUND

Short and long sleep durations are associated with cognitive dysfunction. Given the increased prevalence of sleep abnormalities in the chronic kidney disease (CKD) population, we tested whether the association between sleep duration and cognitive function differed between older adults with and without CKD.

METHODS

This was a study of 3215 older adults (age ≥60 years) enrolled in the National Health and Nutrition Examination Survey (2011-14) evaluating sleep duration, cognitive function (immediate recall, delayed recall, verbal fluency, executive function and processing speed and global cognition) and kidney function. We quantified the association between sleep duration and cognitive function using linear regression and tested whether the associations differed among those with CKD and without using a Wald test for interaction.

RESULTS

Among 3215 participants, 13.3% reported 2-5 hours of sleep/day, 75.2% reported 6-8 hours, and 11.5% reported ≥9 hours. Persons with CKD were more likely to sleep ≥9 hours [odds ratio 1.73 (95% confidence interval 1.22-2.46)]. Among participants with CKD, those with a sleep duration ≥9 hours demonstrated worse global cognitive function (P for interaction = .01), immediate recall (P for interaction = .01) and verbal fluency (P for interaction = .004) than those with a sleep duration of 6-8 h; no differences were observed for participants with CKD who slept 2-5 hours. Among participants without CKD, sleep was not associated with any measures of cognitive function.

CONCLUSIONS

Longer sleep duration is associated with worse cognitive function only among persons with CKD, and global cognition, delayed recall and verbal fluency are particularly affected. Studies should identify interventions to improve sleep patterns and quality in this population.

Prevalence of post-dialysis fatigue: a systematic review and meta-analysis

OBJECTIVES

The purpose of this study was to synthesise data on the prevalence of post-dialysis fatigue (PDF) among haemodialysis (HD) patients.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

China National Knowledge Infrastructure, Wanfang, Chinese Biological Medical Database, PubMed, EMBASE and Web of Science were searched from their inception to 1 April 2022.

ELIGIBILITY CRITERIA

We selected patients who must receive HD treatment for at least 3 months. Cross-sectional or cohort studies published in Chinese or English were eligible for inclusion. The main search terms used in the abstract were: "renal dialysis", "hemodialysis" and "post-dialysis", in combination with the word "fatigue".

DATA EXTRACTION AND SYNTHESIS

Two investigators independently performed data extraction and quality assessment. Data were pooled to estimate the overall prevalence of PDF among HD patients using the random-effects model. Cochran's Q and I² statistics were adopted to evaluate heterogeneity.

RESULT

A total of 12 studies were included, with 2152 HD patients, of which 1215 were defined as having PDF. The overall prevalence of PDF in HD patients was 61.0% (95% CI: 53.6% to 68.3%, p<0.001, I²=90.0%). Subgroup analysis failed to explain the source of heterogeneity, but univariable meta-regression showed that a mean age of ≥50 years might be the source of heterogeneity. Egger's test revealed no publication bias among the studies (p=0.144).

CONCLUSIONS

PDF is highly prevalent among HD patients.

Quality of life in the older adults: The protective role of self-efficacy in adequate coping in patients with chronic diseases

The purpose of the present study was to establish the association between self-efficacy, perception of disease, emotional regulation, and fatigue and the health-related quality of life in older adults living in the departments of Cesar and Atlántico in Colombia and who have been diagnosed with a chronic disease. The participants were 325 older adults of both sexes, with literacy and no presence of cognitive impairment in the Mini-Mental State Examination (MMSE); A non-probabilistic sampling was carried out. We used the MOS-SF-36 questionnaire, the Brief Illness Perception Questionnaire scale for measuring the perception of disease, the Stanford Patient Education Research Center’s Chronic Disease Self self-efficacy questionnaire for chronic patients, the Difficulties in Emotional Regulation Scale, and the Fatigue Severity Questionnaire as measurement instruments. The design was non-experimental cross-sectional with a correlational scope. The results indicate that self-efficacy, disease perception, emotional regulation and severity of fatigue are variables that could impact the physical function of quality of life, confirming that self-efficacy would work as a factor that decreases the probability that a participant score low on this dimension of quality of life. On the other hand, both the perception of the disease and the severity of fatigue were identified as factors that probably negatively influence quality of life.

Neural Drive Impairment in Chronic Kidney Disease Patients Is Associated with Neuromuscular Fatigability and Fatigue

INTRODUCTION

Chronic kidney disease (CKD) patients have a high degree of fatigue relating to neuromuscular symptoms. There is a lack of evidence regarding the etiology of neuromuscular fatigability in elderly CKD patients.

METHODS

Inclusion criteria are as follows: age ≥60 yr, glomerular filtration rate (GFR) <45 mL·min -1 per 1.73 m 2 in CKD patients, and GFR >60 mL·min -1 ·1.73 m -2 in controls. The fatigability protocol consisted in a submaximal handgrip task at 40% peak force. Fatigue was assessed using the Multidimensional Fatigue Inventory-20 items (MFI-20) and the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaires. Peak rate of force development (RFD peak , normalized: NRFD peak ) and rate of EMG rise (RER) were measured during explosive contractions; peak force and mean surface EMG were measured during maximum voluntary contractions. Multilevel models tested neuromuscular parameters adjusted for clinical and Multidimensional Fatigue Inventory-20 items subscales. Neuromuscular fatigability contribution to fatigue description was tested using model comparison.

RESULTS

The study included 102 participants; 45 CKD patients and 57 controls. CKD mainly affected the mental and the reduced motivation subscales of fatigue. CKD was associated with greater neuromuscular fatigability assessed using NRFD peak (group-time interaction, -16.7 % MVF·s -1 , P = 0.024), which increased with fatigue severity ( P = 0.018) and with a higher rate of decrement in RER compared with controls (RER at 50 ms: β = -121.2 μV·s -1 , P = 0.016, and β = -48.5 μV·s -1 , P = 0.196, respectively). Furthermore, these patients show an association between the reduced motivation subscale and the RER (e.g., 30 ms: β = -59.8% EMG peak ·s -1 , P < 0.001). Only peak force fatigability contributed to fatigue variance, whereas RFD peak did not.

CONCLUSIONS

In CKD patients, the neuromuscular fatigability assessed using RFD peak is related to an impairment in motor-unit recruitment or discharge rates, whereas only peak force fatigability was related to fatigue. This suggests that targeting exercise interventions might lessen fatigue and improve quality of life in CKD patients.

Serum 25-Hydroxyvitamin D Level Is Negatively Associated with Fatigue in Elderly Maintenance Hemodialysis Patients

INTRODUCTION

Chronic kidney disease-mineral and bone disorder (CKD-MBD) is frequently observed in maintenance hemodialysis (MHD) patients and is associated with fracture, muscle weakness, malnutrition, etc.; however, relationships of CKD-MBD markers and fatigue are not well established.

METHODS

This was a cross-sectional study including 244 MHD patients (89 elders) from July to September 2021 in the First Affiliated Hospital of Shandong First Medical University. CKD-MBD markers and other clinical data were collected from medical records. Fatigue in the past week was measured by Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) fatigue measure; fatigue at the end of hemodialysis was measured by numeric rating scale (NRS). Spearman correlation, linear regression, and robust linear regression were.

RESULTS

In all MHD patients, lg[25(OH)D] (nmol/L) was negatively correlated with SONG-HD score (β = -1.503, 95% CI: -2.826 to 0.18, p = 0.026) and NRS score (β = -1.532, p = 0.04) in multiple regression models adjusting for sex, age, and all CKD-MBD characters; but no correlations were found on univariate regression or in other multiple regression models. Interaction effects between age ≥65 years and lg(25[OH]D [nmol/L]) in terms of fatigue scores were significant based on multiple linear regressions (SONG-HD score β = -3.613, p for interaction = 0.006; NRS score β = -3.943, p for interaction = 0.008). Compared with non-elderly patients, elderly patients were with higher ACCI scores (7 [6, 8] vs. 4 [3, 5], p < 0.001), higher SONG-HD scores (3 [2, 6] vs. 2 [1, 3], p < 0.001), higher NRS score (4 [2, 7] vs. 3 [1, 5], p < 0.001), lower serum phosphate levels (1.65 [1.29, 2.10] vs. 1.87 [1.55, 2.26] mmol/L, p = 0.002), and lower serum iPTH levels (160.6 [90.46, 306.45] vs. 282.2 [139, 445.7] pg/mL, p < 0.001). There were no differences in serum calcium, alkaline serum, or 25(OH)D levels between the two groups. In elderly patients, lg[25(OH)D] was negatively correlated with SONG-HD score (β = -3.323, p = 0.010) and NRS score (β = -3.521, p = 0.006) on univariate linear regressions. Following adjustment for sex, age, and all CKD-MBD characters, lg[25(OH)D] was negatively correlated with SONG-HD scores (multiple linear regression β = -4.012, p = 0.004; multiple robust regression β = -4.012, p = 0.003) or NRS scores (multiple linear regression β = -4.104, p = 0.002; multiple robust regression β = -4.104, p = 0.001). There were no significant correlations between fatigue scores and other CKD-MBD markers (calcium, phosphate, lgiPTH, alkaline phosphatase) in elderly MHD patients, on either univariate linear regressions or multiple regressions.

CONCLUSION

Serum 25(OH)D level is negatively associated with fatigue in elderly MHD patients.

Ubiquitin-specific protease 11 promotes partial epithelial-to-mesenchymal transition by deubiquitinating the epidermal growth factor receptor during kidney fibrosis

The aberrant expression of ubiquitin-specific protease 11 (USP11) is believed to be related to tumor progression. However, few studies have reported the biological function and clinical importance of USP11 in kidney fibrosis. Here, we demonstrated USP11 was highly upregulated in the kidneys from patients with chronic kidney disease and correlated positively with fibrotic lesion but negatively with kidney function. Conditional USP11 deletion or pharmacologic inhibition with Mitoxantrone attenuated pathological lesions and improved kidney function in both hyperuricemic nephropathy (HN)- and folic acid (FA)-induced mouse models of kidney fibrosis. Mechanistically, by RNA sequencing, USP11 was found to be involved in nuclear gene transcription of the epidermal growth factor receptor (EGFR). USP11 co-immunoprecipitated and co-stained with extra-nuclear EGFR and deubiquitinated and protected EGFR from proteasome-dependent degradation. Genetic or pharmacological depletion of USP11 facilitated EGFR degradation and abated augmentation of TGF-β1 and downstream signaling. This consequently alleviated the partial epithelial-mesenchymal transition, G2/M arrest and aberrant secretome of profibrogenic and proinflammatory factors in uric acid-stimulated tubular epithelial cells. Moreover, USP11 deletion had anti-fibrotic and anti-inflammatory kidney effects in the murine HN and FA models. Thus, our study provides evidence supporting USP11 as a promising target for minimizing kidney fibrosis and that inhibition of USP11 has potential to be an effective strategy for patients with chronic kidney disease.

Fatigue in Patients on Chronic Hemodialysis: The Role of Indoleamine 2,3-Dioxygenase (IDO) Activity, Interleukin-6, and Muscularity

Fatigue is a frequent symptom in hemodialysis (HD), and the indolamine-2,3-dioxygenase (IDO) metabolic trap has been hypothesized in the pathogenesis of fatigue. The association between IDO activity according to fatigue and its relationship with muscle mass and function in HD patients was verified. Chronic HD patients were considered, and fatigue was assessed. The plasma kynurenines and tryptophan ratio (Kyn/Trp), as surrogate of IDO activity, and interleukin (IL)-6 were measured. Muscularity was assessed by BIA and muscle strength by hand-grip dynamometer. 50 HD patients were enrolled, and fatigue was present in 24% of the cohort. Patients with fatigue showed higher Kyn/Trp (p = 0.005), were older (p = 0.007), and IL-6 levels resulted higher than in non-fatigue patients (p < 0.001). HD patients with fatigue showed lower intracellular water (surrogate of muscle mass) (p < 0.001), as well as lower hand grip strength (p = 0.02). The Kyn/Trp ratio positively correlated with IL-6 and ECW/ICW (p = 0.004 and p = 0.014). By logistic regression analysis, higher ICW/h² was associated with lower odds of fatigue (OR, 0.10; 95% CI, 0.01 to 0.73). In conclusion, our cohort fatigue was associated with a higher Kyn/Trp ratio, indicating a modulation of IDO activity. The Kyn/Trp ratio correlated with IL-6, suggesting a potential role of IDO and inflammation in inducing fatigue and changes in muscularity.

The Role of Mitochondrial and Redox Alterations in the Skeletal Myopathy Associated with Chronic Kidney Disease

Significance: An estimated 700 million people globally suffer from chronic kidney disease (CKD). In addition to increasing cardiovascular disease risk, CKD is a catabolic disease that results in a loss of muscle mass and function, which are strongly associated with mortality and a reduced quality of life. Despite the importance of muscle health and function, there are no treatments available to prevent or attenuate the myopathy associated with CKD. Recent Advances: Recent studies have begun to unravel the changes in mitochondrial and redox homeostasis within skeletal muscle during CKD. Impairments in mitochondrial metabolism, characterized by reduced oxidative phosphorylation, are found in both rodents and patients with CKD. Associated with aberrant mitochondrial function, clinical and preclinical findings have documented signs of oxidative stress, although the molecular source and species are ill-defined. Critical Issues: First, we review the pathobiology of CKD and its associated myopathy, and we review muscle cell bioenergetics and redox biology. Second, we discuss evidence from clinical and preclinical studies that have implicated the involvement of mitochondrial and redox alterations in CKD-associated myopathy and review the underlying mechanisms reported. Third, we discuss gaps in knowledge related to mitochondrial and redox alterations on muscle health and function in CKD. Future Directions: Despite what has been learned, effective treatments to improve muscle health in CKD remain elusive. Further studies are needed to uncover the complex mitochondrial and redox alterations, including post-transcriptional protein alterations, in patients with CKD and how these changes interact with known or unknown catabolic pathways contributing to poor muscle health and function. Antioxid. Redox Signal. 38, 318-337.

Lactate: a pearl dropped in the ocean-an overlooked signal molecule in physiology and pathology

Lactate, once recognized as a wasty product from anaerobic glycolysis, is proved to be a pivotal signal molecule. Lactate accumulation occurs in diverse physiological and pathological settings due to the imbalance between lactate production and clearance. Under the condition with drastic changes in local microenvironment, such as tumorigenesis, inflammation, and microbial infection, the glycolysis turns to be active in surrounding cells leading to increased lactate release. Meanwhile, lactate can be utilized by these cells as an energy substrate and acts as a signal molecule to regulate cell functions through receptor-dependent or independent pathways. In this review, we tended to tease out the contribution of lactate in tumor progression and immunomodulation. And we also discussed the accessory role of lactate, beyond as the energy source only, in the growth of invading pathogens.

Impact of Exercise on Fatigue in Patients Undergoing Dialysis in a Tertiary Care Hospital

Background Chronic kidney disease (CKD) is a current public health problem associated with progression to end-stage renal disease (ESRD), cardiovascular disease, and increased mortality rates. The disease is progressive. It is estimated that there are about 20-25 patients with milder kidney damage for every patient on renal replacement therapy. Physical activity is one of the critical elements for the prevention of chronic diseases and exercises in CKD help to improve muscular strength, cardiorespiratory endurance, overall function, and quality of life. Fatigue can cause an inability to perform exercises and can affect physiological and psychological function. There is a need to analyze the effects of exercises on fatigue in outpatients undergoing dialysis in the Indian rural population. Methods This study was a randomized, controlled, interventional, single-center trial. The participants diagnosed with ESRD and who were on hemodialysis were randomly assigned to group A, the exercise group (EG), which had exercise training during dialysis, and group B, the control group (CG), which had no added exercises during dialysis or at home and followed a standard routine method. The outcome measure of fatigue was evaluated through the total Fatigue Assessment Scale (FAS) score at 0, 12, 24, and 36 weeks. The exercise was pilot tested and planned based on the guidelines and carried out during hemodialysis two days a week. It was followed up with a five-day home exercise program when the patients did not undergo dialysis. Results A total of 48 participants were chosen for the study, of which 30 participants completed 36 weeks of training, with exercise adherence of more than 60%. There was a statistically significant difference in FAS between the two groups (F (3, 84) = 10.513, P < 0.001) at a 95% confidence interval (P < 0.05). Post hoc comparisons between groups at baseline and at 12 weeks indicated that there was no significant difference in FAS (P = 0.271 and P = 0.08), but recorded a significant difference (P = 0.001) at 24 and 36 weeks, respectively, between the EG and CG. Conclusions The results indicate that the intradialytic exercise intervention was effective in reducing the level of fatigue in outpatients undergoing dialysis on a long-term exercise program.

Fatigue assessment and its predictors in pediatric patients with chronic kidney disease stages III to V

Background

Chronic fatigue is an intense subjective feeling of mental or physical exhaustion. It influences patients’ daily functioning and quality of life, delays recovery, and increases mortality, especially in chronic kidney disease (CKD) patients. The aim of this study is to assess and determine predictors of chronic fatigue in children with ESRD, dialysis, and pre-dialysis stages that can affect the patients’ quality of life (QOL).

Methods

We conducted a cross-sectional study on 114 patients diagnosed with CKD stages III to V, following at the nephrology outpatient clinic and hemodialysis (HD) unit of Cairo University Children’s Hospital during the period September 2020 till April 2021. Demographic and laboratory data of patients were gathered, and dialytic analysis in the form of frequency, duration of dialysis sessions, and adequacy of hemodialysis was calculated. The fatigue severity score (FSS) questionnaire was used to assess fatigue’s effects on daily functions, querying its relationship to motivation, physical activity, work, family, and social life.

Results

The mean age in the current study was (8.8 ± 1.8) years, with 62% being males. The median FSS score was 5.8, with a higher FSS score in stage V CKD patients. High e-GFR, serum sodium, folic acid, and L-carnitine supplementation all reduced the intensity of fatigue, while prolonged HD duration, acidosis, hypertension, and non-compliance to vitamin D replacement increased tiredness severity.

Conclusion

Routine fatigue assessment and measures to reduce it is a fundamental issue in pediatric CKD patients for better QOL.