Fatigue is a predictor for cardiovascular outcomes in patients undergoing hemodialysis

Possible clinical effects of molecular hydrogen (H2) delivery during hemodialysis in chronic dialysis patients: Interim analysis in a 12 month observation

Background and aim

It is supposed that enhanced oxidative stress and inflammation are involved with the poor clinical outcomes in patients on chronic dialysis treatment. Recent studies have shown that molecular hydrogen (H₂) is biologically active as an anti-inflammatory agent. Thus, we developed a novel hemodialysis (E-HD) system which delivers H₂ (30 to 80 ppb)-enriched dialysis solution, to conduct a prospective observational study (UMIN000004857) in order to compare the long-term outcomes between E-HD and conventional-HD (C-HD) in Japan. The present interim analysis aimed to look at potential clinical effects of E-HD during the first 12 months observation.

Subjects and method

262 patients (140, E-HD; 122, C-HD) were subjected for analysis for comprehensive clinical profiles. They were all participating in the above mentioned study, and they had been under the respective HD treatment for 12 consecutive months without hospitalization. Collected data, such as, physical and laboratory examinations, medications, and self-assessment questionnaires on subjective symptoms (i.e., fatigue and pruritus) were compared between the two groups.

Results

In a 12-month period, no clinical relevant differences were found in dialysis-related parameters between the two groups. However, there were differences in the defined daily dose of anti-hypertensive agents, and subjective symptoms, such as severe fatigue, and pruritus, which were all less in the E-HD group. Multivariate analysis revealed E-HD was an independent significant factor for the reduced use of anti-hypertensive agents as well as the absence of severe fatigue and pruritus at 12 months after adjusting for confounding factors.

Conclusion

The data indicates E-HD could have substantial clinical benefits beyond conventional HD therapy, and support the rationale to conduct clinical trials of H₂ application to HD treatment.

Serum Macro TSH Level is Associated with Sleep Quality in Patients with Cardiovascular Risks - HSCAA Study

Macro thyroid-stimulating hormone (TSH) has been reported to be associated with seasonality and regulated by changes in day length in rodents, different from free TSH. In the present study, we investigated structural differences between macro TSH and free TSH levels in human serum, as well as the association of macro TSH with sleep quality. We enrolled 314 patients registered in the Hyogo Sleep Cardio-Autonomic Atherosclerosis (HSCAA) study. Sleep quality shown by actigraphy, sleep physical activity, and percent sleep in all and TSH closely matched subjects were significantly associated with high macro TSH levels. Macro and free TSH were similarly increased following thyrotropin-releasing hormone (TRH) stimulation, while circadian changes associated with those were distinct. To further analyze the structure of macro TSH, serum samples were separated by gel filtration chromatography. Although treatment with glycosidase did not affect morbidity, the macro TSH fraction had a markedly low affinity to the Con A column as compared with free TSH, indicating a distinct glycosylation structure. In conclusion, an increase in serum macro TSH is associated with low sleep quality and regulated in a manner distinct from free TSH, potentially due to an altered glycosylation structure.

1-year course of fatigue in patients on chronic hemodialysis

PURPOSE

Fatigue is common in end-stage renal disease patients receiving hemodialysis, reduces significantly their quality of life and is associated with all-cause and cardiac-related mortality. Unfortunately, little is known about the course of fatigue in patients on chronic hemodialysis.

METHODS

The Vitality Subscale of the SF-36 (SF-36 VS), Short-Form Health Survey, was administered to 45 patients in January (T1), June (T2) and November (T3) 2015.

RESULTS

The score of the SF-36 VS did not differ significantly among T1, T2 and T3. Similarly, the 1-year course of the SF-36 Vitality Subscale score did not differ significantly among T1, T2 and T3 after stratification of patients for sex, age, BMI, IADL and Charlson. Between T1 and T2, 21 out of 45 patients (46.6%) changed their fatigue status: 8 fatigued patients became not-fatigued and 13 not-fatigued patients became fatigued. Between T2 and T3, 12 out of 45 (26.6%) patients changed their fatigue status: 5 fatigued patients became not-fatigued and 7 not-fatigued patients became fatigued. Between T1 and T3, 19 out of 45 patients (42.2%) changed their fatigue status: 6 fatigued patients became not-fatigued and 13 not-fatigued became fatigued.

CONCLUSION

The present study is the first to identify variations in fatigue status among patients on chronic hemodialysis during 1-year course. These findings suggest to frequently assess the presence and severity of fatigue in patients on chronic hemodialysis.

The role of psychological factors in fatigue among end-stage kidney disease patients: a critical review

Fatigue is a common and debilitating symptom, affecting 42-89% of end-stage kidney disease patients, persisting even in pre-dialysis care and stable kidney transplantation, with huge repercussions on functioning, quality of life and patient outcomes. This paper presents a critical review of current evidence for the role of psychological factors in renal fatigue. To date, research has concentrated primarily on the contribution of depression, anxiety and subjective sleep quality to the experience of fatigue. These factors display consistent and strong associations with fatigue, above and beyond the role of demographic and clinical factors. Considerably less research is available on other psychological factors, such as social support, stress, self-efficacy, illness and fatigue-specific beliefs and behaviours, and among transplant recipients and patients in pre-dialysis care. Promising evidence is available on the contribution of illness beliefs and behaviours to the experience of fatigue and there is some indication that these factors may vary according to treatment modality, reflecting the differential burdens and coping necessities associated with each treatment modality. However, the use of generic fatigue scales casts doubt on what specifically is being measured among dialysis patients, illness-related fatigue or post-dialysis-specific fatigue. Therefore, it is important to corroborate the available evidence and further explore, qualitatively and quantitatively, the differences in fatigues and fatigue-specific beliefs and behaviours according to renal replacement therapy, to ensure that any model and subsequent intervention is relevant and grounded in the experiences of patients.

Plasma leptin concentration is associated with fatigue severity in patients with cardiovascular risk factors - HSCAA study

Fatigue induced by complex dysfunctions of the central nervous system is frequently complained by patients with cardiovascular risk factors. Although leptin is considered to regulate the central nervous system, there are no reports regarding its association with fatigue in those patients. This cross-sectional study included 347 patients with cardiovascular risk factors. Fatigue score and plasma leptin concentration were measured. In addition, abdominal fat accumulation, systemic inflammation, sleep condition, and functions of hypothalamus-pituitary axis and autonomic system were estimated. Plasma leptin concentration (natural logarithm transformed) was significantly and positively (r=0.222, p<0.001) associated with fatigue score, and significantly (p<0.001) higher in the moderately-fatigued group (2.32±0.75ng/ml, mean±SD, n=52) than in the normally-fatigued group (1.85±1.02ng/ml, mean±SD, n=295). Multiple logistic regression analysis showed that plasma leptin concentration was significantly and independently associated with a moderately-fatigued condition independent of other factors, including age, gender, presence of diabetes, hypertension, dyslipidemia, alcohol consumption habit, urinary free cortisol, serum high-sensitive CRP concentration, visceral and subcutaneous fat area, apnea/hypopnea index, sleep efficiency, and heart rate variability. Hyperleptinemia may contribute to fatigue severity in patients with cardiovascular risk factors.

Both low and high serum ferritin levels predict mortality risk in hemodialysis patients without inflammation

Background

Serum ferritin concentration >100 ng/mL was associated with a higher risk of death in hemodialysis patients in Japan, whereas such an association was less clear in hemodialysis patients in Western countries. Since Japanese dialysis patients are generally less inflamed than those in Western countries, inflammation may modify the association between serum ferritin and the adverse outcomes.

Methods

We performed an observational cohort study using data from 2606 Japanese hemodialysis patients who participated in the Dialysis Outcomes and Practice Patterns Study (DOPPS) III (2005–2008) or DOPPS IV (2009–2012). The predictor was serum ferritin category (<50, 50–99.9, 100–199.9, and ≥200 ng/mL), and the primary and secondary outcomes were all-cause mortality and cardiovascular hospitalization, respectively. C-reactive protein (CRP, cut-off by 0.3 mg/dL) and serum albumin (cut-off by 3.8 g/dL) were stratification factors related to systemic inflammation.

Results

After adjustment for relevant confounding factors, a U-shaped association was observed between serum ferritin and all-cause mortality in the group with low CRP levels, whereas such relationship was not significant in the high CRP counterparts. In contrast, we found a linear association between serum ferritin and cardiovascular hospitalization in the low CRP and high CRP groups commonly. Similar results were obtained when the total cohort was stratified by serum albumin.

Conclusions

Serum ferritin showed different patterns of association with all-cause mortality in hemodialysis patients with versus without inflammation, whereas its association with cardiovascular hospitalization was similar regardless of inflammatory conditions.

Association of Erythropoietin Resistance with Fatigue in Hemodialysis Patients: A Cross-Sectional Study

BACKGROUND/AIMS

Fatigue is a common symptom in patients receiving hemodialysis (HD) and is generally associated with anemia. However, it can be difficult to resolve, even when anemia has been treated using erythropoiesis-stimulating agents and iron replacement therapy. In the present study, we examined the associations of anemia, the erythropoietin resistance index (ERI) and iron deficiency with fatigue during HD.

METHODS

In this cross-sectional study, fatigue score was calculated on the basis of questionnaire responses in HD patients. Participants were divided into 3 groups according to their hemoglobin (Hb) levels (low, normal and high). Iron deficiency was assessed as a transferrin saturation (TSAT) of <20%.

RESULTS

We included 571 HD patients (men/women 368/203; mean age 62.2 ± 10.8 years). Among the 3 groups, fatigue scores increased significantly with decreasing Hb levels. HD patients with low Hb levels (<90 g/l) had significantly higher fatigue scores than those with higher Hb levels (≥120 g/l). In the multiple regression analysis, we showed that a high ERI (β = 0.208) and a low TSAT (β = -0.155), but not the Hb level, were significantly associated with increased fatigue score. Moreover, this was independent of age, gender and modifiable confounders linked to anemia. Even after restricting patients to those without iron deficiency (TSAT ≥20%), the ERI (β = 0.258) retained a significant and independent association with the fatigue score.

CONCLUSION

Iron deficiency and a high ERI despite iron sufficiency may cause fatigue in HD patients.

Associations of Sleep Quality and Awake Physical Activity with Fluctuations in Nocturnal Blood Pressure in Patients with Cardiovascular Risk Factors

BACKGROUND

Sleep quality and awake physical activity are important behavioral factors involved in the occurrence of cardiovascular diseases, potentially through nocturnal blood pressure (BP) changes. However, the impacts of quantitatively measured sleep quality and awake physical activity on BP fluctuation, and their relationships with several candidate causal factors for nocturnal hypertension are not well elucidated.

METHODS

This cross-sectional study included 303 patients registered in the HSCAA study. Measurements included quantitatively determined sleep quality parameters and awake physical activity obtained by actigraph, nocturnal systolic BP (SBP) fall [100 × (1- sleep SBP/awake SBP ratio)], apnea hypopnea index, urinary sodium and cortisol secretion, plasma aldosterone concentration and renin activity, insulin resistance index, parameters of heart rate variability (HRV), and plasma brain-derived neurotrophic factor (BDNF).

RESULTS

Simple regression analysis showed that time awake after sleep onset (r = -0.150), a parameter of sleep quality, and awake physical activity (r = 0.164) were significantly correlated with nocturnal SBP fall. Among those, time awake after sleep onset (β = -0.179) and awake physical activity (β = 0.190) were significantly and independently associated with nocturnal SBP fall in multiple regression analysis. In a subgroup of patients without taking anti-hypertensive medications, both time awake after sleep onset (β = -0.336) and awake physical activity (β = 0.489) were more strongly and independently associated with nocturnal SBP falls.

CONCLUSION

Sleep quality and awake physical activity were found to be significantly associated with nocturnal SBP fall, and that relationship was not necessarily confounded by candidate causal factors for nocturnal hypertension.

Pursuing minimally disruptive medicine: disruption from illness and health care-related demands is correlated with patient capacity

BACKGROUND

Chronic conditions burden patients with illness and treatments. We know little about the disruption of life by the work of dialysis in relation to the resources patients can mobilize, that is, their capacity, to deal with such demands. We sought to determine the disruption of life by dialysis and its relation to patient capacity to cope.

METHODS

We administered a survey to 137 patients on dialysis at an academic medical center. We captured disruption from illness and treatment, and physical, mental, personal, social, financial, and environmental aspects of patient capacity using validated scales. Covariates included number of prescriptions, hours spent on health care, existence of dependents, age, sex, and income level.

RESULTS

On average, patients reported levels of capacity and disruption comparable to published levels. In multivariate regression models, limited physical, financial, and mental capacity were significantly associated with greater disruption. Patients in the top quartile of disruption had lower-than-expected physical, financial, and mental capacity.

CONCLUSIONS

Our sample generally had capacity comparable to other populations and may be able to meet the demands imposed by treatment. Those with reduced physical, financial, and mental capacity reported higher disruption and represent a vulnerable group that may benefit from innovations in minimally disruptive medicine.

Frontier studies on fatigue, autonomic nerve dysfunction, and sleep-rhythm disorder

Fatigue is defined as a condition or phenomenon of decreased ability and efficiency of mental and/or physical activities, caused by excessive mental or physical activities, diseases, or syndromes. It is often accompanied by a peculiar sense of discomfort, a desire to rest, and reduced motivation, referred to as fatigue sensation. Acute fatigue is a normal condition or phenomenon that disappears after a period of rest; in contrast, chronic fatigue, lasting at least 6 months, does not disappear after ordinary rest. Chronic fatigue impairs activities and contributes to various medical conditions, such as cardiovascular disease, epileptic seizures, and death. In addition, many people complain of chronic fatigue. For example, in Japan, more than one third of the general adult population complains of chronic fatigue. It would thus be of great value to clarify the mechanisms underlying chronic fatigue and to develop efficient treatment methods to overcome it. Here, we review data primarily from behavioral, electrophysiological, and neuroimaging experiments related to neural dysfunction as well as autonomic nervous system, sleep, and circadian rhythm disorders in fatigue. These data provide new perspectives on the mechanisms underlying chronic fatigue and on overcoming it.

The impact of depression on fatigue in patients with haemodialysis: a correlational study

AIMS AND OBJECTIVES

To investigate the fatigue levels and important fatigue predictors for patients undergoing haemodialysis.

BACKGROUND

Fatigue is a common symptom for haemodialysis patients. With its debilitating and distressing effects, it impacts patients in terms of their quality of life while also increasing their mortality rate.

DESIGN

A descriptive correlational study.

METHODS

Convenience sampling was conducted at six chosen haemodialysis centres in Southern Taiwan. Data were collected via a structured questionnaire from 193 haemodialysis patients. The scales involved in this study were socio-demographic details, the Center for Epidemiologic Studies Depression Scale, and the Fatigue Scale for haemodialysis patients. Data analysis included percentages, means, standard deviations and hierarchical multiple regression analysis.

RESULTS

The fatigue level for haemodialysis patients was in the moderate range. Results from the hierarchical multiple regression analysis indicated that age, employment status, types of medications, physical activity and depression were significant. Of those variables, depression had the greatest impact on the patients' fatigue level, accounting for up to 30·6% of the explanatory power. The total explanatory power of the regression model was 64·2%.

CONCLUSION

This study determined that for haemodialysis patients, unemployment, increased age, taking more medications or lower exercise frequencies resulted in more severe depression, which translated in turn to higher levels of fatigue. Among all these factors, depression had the greatest impact on the patients' fatigue levels.

RELEVANCE TO CLINICAL PRACTICE

Not only is this finding beneficial to future studies on fatigue as a source of reference, it is also helpful in our understanding of important predictors relating to fatigue in the everyday lives of haemodialysis patients. It is recommended that when caring for fatigued patients, more care should be dedicated to their psychological states, and assistance should be provided in a timely way so as to reduce the amount of fatigue suffered.

Effects of nutritional supplementation on fatigue, and autonomic and immune dysfunction in patients with end-stage renal disease: a randomized, double-blind, placebo-controlled, multicenter trial

BACKGROUND

Fatigue is a predictor of cardiovascular events in patients with end-stage renal disease (ESRD) undergoing hemodialysis treatment. We hypothesized that multinutritional support would improve quality of life, fatigue symptoms, and potential quantitative measures including endocrine, immune and autonomic functions in patients with ESRD undergoing hemodialysis.

METHODS

Two hundred and two hemodialysis patients were randomly assigned to receive active treatment (containing vitamin B1, vitamin B2, niacin, vitamin B6, vitamin B12, folic acid, vitamin C, carnitine, coenzyme Q10, naïve galacto-oligosaccharide, and zinc) or placebo after each dialysis session for 12 weeks. The patients and attending physicians were blinded to the treatment, and 172 patients (86 in each group) completed the study. Fatigue was evaluated via fatigue questionnaire at 0, 4, and 12 weeks. To assess human herpes virus (HHV) 6 and 7 reactivation, numbers of viral DNA copies were determined in saliva by polymerase chain reaction at weeks 0 and 12. Autonomic function was determined via measurement of beat-to-beat variation by using acceleration plethysmography.

RESULTS

Clinical characteristics, changes in fatigue, quality of life score, endocrine functions, and laboratory data did not differ significantly between the two groups. Several parameters of heart rate variability significantly increased after nutritional treatment compared to placebo. Nutritional drink for 12 weeks significantly suppressed HHV7 DNA copy numbers. Similarly, HHV6 DNA copy numbers tended to be decreased by treatment but without reaching statistical significance.

CONCLUSIONS

Nutritional supplementation may modulate immune and autonomic dysfunction in ESRD patients undergoing hemodialysis.

Psychometric properties of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in Chinese patients receiving maintenance dialysis

CONTEXT

Fatigue is a common symptom reported by patients with end-stage renal disease, and it can significantly decrease patients' quality of life. A brief and convenient fatigue assessment tool is needed for Chinese patients on maintenance dialysis.

OBJECTIVES

To determine the psychometric characteristics of the Chinese version of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in patients receiving maintenance dialysis.

METHODS

The Chinese version of the FACIT-Fatigue was obtained from the FACIT system. Test-retest reliability of this scale was examined using intraclass correlation coefficients, and the internal consistency was calculated by Cronbach's alpha. Content validity was examined using the content validity index (CVI), scale-level CVI/universal agreement, and scale-level CVI/average agreement. Construct validity was tested using Pearson product-moment correlations of the FACIT-Fatigue scores with the Revised Piper Fatigue Scale, Hospital Anxiety and Depression Scale, Pittsburgh Sleep Quality Index, and disease characteristics during the same period.

RESULTS

A total of 172 patients (111 males and 61 females, mean age 52.6 ± 12.5 years) completed this study, with a median FACIT-Fatigue score of 41 (first and third quartiles 34.3-46). The Chinese version of the FACIT-Fatigue had excellent test-retest reliability (intraclass correlation coefficient = 0.98) and internal consistency (Cronbach's alpha = 0.92); the validity of the scale was supported by CVI, scale-level CVI/universal agreement, and scale-level CVI/average agreement values of at 0.67-1, 0.85, and 0.96, respectively. The standard error of measurement of the FACIT-Fatigue was 1.2. The significant correlations between the FACIT-Fatigue score and the Revised Piper Fatigue Scale (r = -0.658), Hospital Anxiety and Depression Scale (-0.566), and Pittsburgh Sleep Quality Index (-0.489) were supported by the FACIT-Fatigue, with good construct validity (all P < 0.01).

CONCLUSION

The FACIT-Fatigue had acceptable validity and reliability for maintenance dialysis patients and can be used as a valid tool for the measurement of fatigue among these Chinese patients.

Sleep, cardiac autonomic function, and carotid atherosclerosis in patients with cardiovascular risks: HSCAA study

OBJECTIVES

Behavioral and psychosocial factors have been gaining increased attention in regard to cardiovascular diseases. We evaluated sleep conditions, cardiac autonomic function, and carotid atherosclerosis in subjects who participated in the Hyogo Sleep Cardio-Autonomic Atherosclerosis (HSCAA) Study.

METHODS

This cross-sectional study included 330 serial patients registered in the HSCAA study who were free from past cardiovascular diseases, and prescribing α- or β-blockers. In addition to clinical background and classical cardiovascular risk factors, sleep efficiency, apnea hypopnea index (AHI), awake physical activity, heart rate variability (HRV), carotid intima-media thickness (IMT), presence of plaque and plaque score were determined.

RESULTS

Sleep efficiency (r = -0.183) and all HRV parameters (SDNN: r = -0.202; rMSSD: r = -0.234; pNN50: r = -0.277) were significantly (p < 0.01) and negatively associated with IMT, while AHI (r = 0.220, p < 0.001) was positively associated with IMT. Similarly, sleep efficiency (r = -0.129), HRV parameters (SDNN: r = -0.170; rMSSD: r = -0.217; pNN50: r = -0.260) and AHI (r = 0.184) were also significantly (p < 0.05) associated with plaque scores. Multivariate logistic regression analyses showed that rMSSD, but not sleep efficiency or AHI, was significantly associated with carotid plaque (OR 0.74, 95% CI 0.56-0.98, p = 0.037), independent of classical risk factors. The association of rMSSD with carotid plaque remained significant even after adjustment for sleep efficiency or AHI. A comparison of risk factors in specific subgroups showed that the association of lower HRV with carotid plaque was more prominent in patients with cardiovascular risk factors including male gender, hypertension, dyslipidemia and diabetes mellitus.

CONCLUSION

Cardiac autonomic nervous dysfunction was independently associated with carotid atherosclerosis, independent of sleep condition. Moreover, that association was more prominent in specific subgroups with cardiovascular risk factors.

Neural mechanisms underlying chronic fatigue

Fatigue is defined as a condition or phenomenon of declined ability and efficiency of mental and/or physical activities, caused by excessive mental or physical activities, diseases, or syndromes. Acute fatigue is a normal condition that disappears after a period of rest; in contrast, chronic fatigue does not disappear after an ordinary rest. Chronic fatigue impairs daily activities and contributes to various medical conditions and death. In addition, many people complain of chronic fatigue. It would thus be of great value to clarify the mechanisms underlying chronic fatigue and to develop efficient treatment methods to overcome it. Here, we review data primarily from behavioral, neurophysiological, and neuroimaging experiments related to the neural mechanisms underlying chronic fatigue. We propose that repetitive and prolonged overwork and/or stress cause neural damage of a facilitation system, as well as central sensitization and classical conditioning of an inhibition system. We also propose a new treatment strategy for chronic fatigue on the basis of its underlying neural mechanisms.

Regulatory mechanism of performance in chronic cognitive fatigue

Chronic cognitive fatigue is characterized by a sensation of long-lasting fatigue that impairs cognitive functions. Facilitation and inhibition systems in the central nervous system play primary roles in determining the output to the peripheral system, that is, performance. Sensory input from the peripheral system to the central nervous system activates the inhibition system to limit performance, whereas motivational input activates the facilitation system to enhance performance. The dysfunction of the facilitation system and central sensitization and classical conditioning of the inhibition system play important roles in the pathophysiology of chronic cognitive fatigue. Because the dorsolateral prefrontal cortex receives input from both the facilitation and inhibition systems to determine performance, metabolic, functional, and structural impairments of the dorsolateral prefrontal cortex induced by repetitive and prolonged overwork, stress, and stress responses contribute to the impaired functioning and cognitive performance that occur in people with chronic cognitive fatigue. This hypothesis of the regulatory mechanism of performance provides a new perspective on the neural mechanisms underlying chronic cognitive fatigue.

Ecological momentary assessment of fatigue, sleepiness, and exhaustion in ESKD

Background

Many patients on maintenance dialysis experience significant sleepiness and fatigue. However, the influence of the hemodialysis (HD) day and circadian rhythms on patients’ symptoms have not been well characterized. We sought to use ecological momentary assessment to evaluate day-to-day and diurnal variability of fatigue, sleepiness, exhaustion and related symptoms in thrice-weekly maintenance HD patients.

Methods

Subjects used a modified cellular phone to access an interactive voice response system that administered the Daytime Insomnia Symptom Scale (DISS). The DISS assessed subjective vitality, mood, and alertness through 19 questions using 7- point Likert scales. Subjects completed the DISS 4 times daily for 7 consecutive days. Factor analysis was conducted and a mean composite score of fatigue-sleepiness-exhaustion was created. Linear mixed regression models (LMM) were used to examine the association of time of day, dialysis day and fatigue, sleepiness, and exhaustion composite scores.

Results

The 55 participants completed 1,252 of 1,540 (81%) possible assessments over the 7 day period. Multiple symptoms related to mood (e.g., feeling sad, feeling tense), cognition (e.g., difficulty concentrating), and fatigue (e.g., exhaustion, feeling sleepy) demonstrated significant daily and diurnal variation, with higher overall symptom scores noted on hemodialysis days and later in the day. In factor analysis, 4 factors explained the majority of the observed variance for DISS symptoms. Fatigue, sleepiness, and exhaustion loaded onto the same factor and were highly intercorrelated. In LMM, mean composite fatigue-sleepiness-exhaustion scores were associated with dialysis day (coefficient and 95% confidence interval [CI] 0.21 [0.02 – 0.39]) and time of day (coefficient and 95% CI 0.33 [0.25 – 0.41]. Observed associations were minimally affected by adjustment for demographics and common confounders.

Conclusions

Maintenance HD patients experience fatigue-sleepiness-exhaustion symptoms that demonstrate significant daily and diurnal variation. The variability in symptoms may contribute to poor symptom awareness by providers and greater misclassification bias of fatigue related symptoms in clinical studies.

Geriatric nutritional risk index is a strong predictor of mortality in hemodialysis patients: data from the Riscavid cohort

INTRODUCTION

Malnutrition is a common complication in hemodialysis (HD) patients and it is related to morbidity and mortality. Although a gold standard method for diagnosis of malnutrition is not available, serum albumin, body weight and height are commonly used and are included in the calculation of the Geriatric nutritional risk index (GNRI). Recently the association between GNRI and mortality in chronic HD patients has been documented in Asian populations. Our aim was to examine the relative reliability of the GNRI as a mortality and morbidity predictor in an Italian HD cohort.

METHODS

We prospectively examined the GNRI of 753 maintenance HD patients aged 65.7 ± 14.1 years, 457 males, included in the Riscavid cohort, and followed them up for 84 months. Predictors for all-cause death were examined using Kaplan-Meier and Cox proportional-hazards analyses.

RESULTS

Low GNRI was significantly associated with signs of wasting, i.e. low Body mass index, hypoalbuminemia, low normalized protein catabolic rate. Patients within the lowest GNRI quartile had a significantly lower survival rate than those in the 2nd to 4th quartile (p < 0.001). Multivariate Cox proportional-hazards analysis demonstrated that the lowest quartile of GNRI was a significant predictor of case mix adjusted all-cause mortality (HR 1.72; CI 1.35-2.18, p < 0.001).

CONCLUSIONS

These results demonstrate that low GNRI (<92) is associated with malnutrition and is a strong predictor of overall mortality in HD patients. However, cardiovascular events did not differ among the GNRI quartiles. A low GNRI score can be considered a simple and reliable marker of malnutrition and predictor for mortality risk in Caucasian HD patients.

Effects of chicken essence on recovery from mental fatigue in healthy males

Background

Fatigue is a common symptom in modern society. There has been a recent resurgence of interest in traditional remedies for fatigue. Chicken essence, which is rich in anserine and carnosine, has been widely taken in Asian countries as a traditional remedy with various aims, including attenuation of physical and mental fatigue. However, the evidence for its efficacy specifically for mental fatigue remains unclear. We examined the effect of essence of chicken on mental fatigue in humans, using our established fatigue-inducing task and evaluation methods.

Material/Methods

In this placebo-controlled crossover study, 20 healthy male volunteers were randomized to receive daily oral administration of essence of chicken or placebo drink provided by Cerebos Pacific Ltd. via Suntory holdings Ltd. for 4 weeks. The participants performed 2-back test trials as a fatigue-inducing mental task and then had a rest session. Just before and after each session, they completed cognitive task trials focusing on selective attention to evaluate the level of mental fatigue.

Results

After essence of chicken intake for 1 and 4 weeks, the reaction times on the cognitive task trials after the rest session were significantly shorter than those at baseline, and significant changes were not observed with placebo intake. The reaction times before and after the fatigue-inducing session were not altered by either essence of chicken or placebo intake.

Conclusions

We showed that daily intake of essence of chicken could be effective for the recovery from mental fatigue and is a promising candidate for use as an anti-fatigue food.

Association of segmental wall motion abnormalities occurring during hemodialysis with post-dialysis fatigue

BACKGROUND

Post-dialysis fatigue (PDF) is a common, debilitating symptom that remains poorly understood. Cardiac wall motion abnormalities (WMAs) may worsen during dialysis, but it is unknown whether WMA are associated with PDF.

METHODS

Forty patients were recruited from University of California San Francisco-affiliated dialysis units between January 2010 and February 2011. Participants underwent echocardiograms before and during the last hour of 79 dialysis sessions. Myocardial segments were graded 1-4 by a blinded reviewer, with four representing the worst WMA, and the segmental scores were summed for each echocardiogram. Patients completed questionnaires about their symptoms. Severe PDF (defined as lasting >2 h after dialysis) was analysed using a generalized linear model with candidate predictors including anemia, intradialytic hemodynamics and cardiac function.

RESULTS

Forty-four percent of patients with worsened WMA (n=9) had severe PDF, compared with 13% of patients with improved or unchanged WMA (P = 0.04). A one-point increase in the WMA score during dialysis was associated with a 10% higher RR of severe PDF [RR: 1.1, 95% CI (1.1, 1.2), P < 0.001]. After multivariable adjustment, every point increase in the WMA score was associated with a 2-fold higher risk of severe PDF [RR: 1.9, 95% CI (1.4, 2.6), P < 0.001]. History of depression was associated with severe PDF after adjustment for demographics and comorbidities [RR: 3.4, 95% CI (1.3, 9), P = 0.01], but anemia, hemodynamics and other parameters of cardiac function were not.

CONCLUSIONS

Although cross-sectional, these results suggest that some patients may experience severe PDF as a symptom of cardiac ischemia occurring during dialysis.

The perception of sleep quality in kidney transplant patients during the first year of transplantation

OBJECTIVE

Poor sleep quality is one of the factors that adversely affects patient quality of life after kidney transplantation, and sleep disorders represent a significant cardiovascular risk factor. The objective of this study was to investigate the prevalence of changes in sleep quality and their outcomes in kidney transplant recipients and analyze the variables affecting sleep quality in the first years after renal transplantation.

METHODS

Kidney transplant recipients were evaluated at two time points after a successful transplantation: between three and six months (Phase 1) and between 12 and 15 months (Phase 2). The following tools were used for assessment: the Pittsburgh Sleep Quality Index; the quality of life questionnaire Short-Form-36; the Hospital Anxiety and Depression scale; the Karnofsky scale; and assessments of social and demographic data. The prevalence of poor sleep was 36.7% in Phase 1 and 38.3% in Phase 2 of the study.

RESULTS

There were no significant differences between patients with and without changes in sleep quality between the two phases. We found no changes in sleep patterns throughout the study. Both the physical and mental health scores worsened from Phase 1 to Phase 2.

CONCLUSION

Sleep quality in kidney transplant recipients did not change during the first year after a successful renal transplantation.

Fatigue in hemodialysis patients: a review of current knowledge

CONTEXT

End-stage renal disease is a common chronic illness increasing in incidence and prevalence. Although kidney function is partially replaced through dialysis, patients endure many symptoms of the disease such as fatigue. Many factors have been studied regarding their relationship with fatigue in this population.

OBJECTIVES

To provide a state of the science review regarding fatigue in hemodialysis patients by examining the experience of fatigue for patients on hemodialysis and correlates of fatigue in patients on hemodialysis.

METHODS

PubMed, the Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and Sociological Abstracts were searched using the key terms "fatigue," "dialysis," and "hemodialysis." Articles written after 1980 and those with explicit findings related to fatigue were included in this review. Articles that discussed fatigue in peritoneal dialysis patients or renal transplant patients were not included.

RESULTS

There is little knowledge regarding the experience of fatigue for patients on hemodialysis and there has been little success identifying demographic, psychosocial, or physiological factors that are consistently related to fatigue.

CONCLUSION

Further work in this area of inquiry would be of benefit and may shed light on the domains of life that are affected by fatigue for hemodialysis patients. It also may help deepen our knowledge regarding correlates that could identify hemodialysis patients who are at increased risk for fatigue.

Effect of mental fatigue on the central nervous system: an electroencephalography study

BACKGROUND

Fatigue can be classified as mental and physical depending on its cause, and each type of fatigue has a multi-factorial nature. We examined the effect of mental fatigue on the central nervous system using electroencephalography (EEG) in eighteen healthy male volunteers.

METHODS

After enrollment, subjects were randomly assigned to two groups in a single-blinded, crossover fashion to perform two types of mental fatigue-inducing experiments. Each experiment consisted of four 30-min fatigue-inducing 0- or 2-back test sessions and two evaluation sessions performed just before and after the fatigue-inducing sessions. During the evaluation session, the participants were assessed using EEG. Eleven electrodes were attached to the head skin, from positions F3, Fz, F4, C3, Cz, C4, P3, Pz, P4, O1, and O2.

RESULTS

In the 2-back test, the beta power density on the Pz electrode and the alpha power densities on the P3 and O2 electrodes were decreased, and the theta power density on the Cz electrode was increased after the fatigue-inducing mental task sessions. In the 0-back test, no electrodes were altered after the fatigue-inducing sessions.

CONCLUSIONS

Different types of mental fatigue produced different kinds of alterations of the spontaneous EEG variables. Our findings provide new perspectives on the neural mechanisms underlying mental fatigue.

Exertional fatigue in patients with CKD

BACKGROUND

Fatigue is one of the most prevalent symptoms in chronic kidney disease (CKD). However, fatigue mechanisms are poorly understood due in part to nonspecific definitions. This study investigates exertional fatigue during simulated activities of daily living, focusing on oxygen delivery and utilization.

STUDY DESIGN

"Explanatory" matched-cohort study.

PARTICIPANTS & SETTING

13 patients with CKD (stages 3b-4; mean age, 62 ± 13 [SD] years) and 13 healthy controls, mean matched for age, height, body mass and composition, and physical activity level. Participants completed an incremental cycle ergometer test to simulate energy expenditure of typical activities of daily living.

FACTOR

4 exercise intensities: 1, 1.8, 2.4, and 3.1 metabolic equivalent tasks (METs).

OUTCOMES

The primary outcome was exertional fatigue by rating of perceived exertion (RPE) on a 6-20 scale.

MEASUREMENTS

Other multidimensional measures of fatigue: UK Short Form Health Survey 36 (UK SF-36) Vitality and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) subscales. Physiologic measures of the oxygen transport and utilization chain (expired gas analysis, cardiac output, and arterial oxygen content) and blood lactate.

RESULTS

RPE was increased in patients compared with controls at 2.4 (10.5 [ie, light] ± 2.7 vs 8.7 [very light] ± 1.7 units) and 3.1 (12.5 [somewhat hard] ± 2.6 vs 10.2 [light] ± 1.7 units) METs (interaction P = 0.03), which was consistent with higher chronic fatigue in patients by both the UK SF-36 Vitality (P = 0.01) and FACIT-Fatigue (P = 0.004) subscales. Arterial oxygen content was decreased in patients (P = 0.001), but cardiac output and oxygen extraction ratio were unchanged, decreasing oxygen delivery (P = 0.04). Respiratory exchange ratio (P = 0.004) and blood lactate production (P = 0.002) were increased.

LIMITATIONS

Those inherent to a matched-cohort study.

CONCLUSIONS

Using a novel application of the outcome measure RPE, patients with non-dialysis-dependent CKD reported considerable exertional fatigue during simulated activities of daily living. Poor compensation for mild anemia contributed to this symptom. In addition to anemia, the entire oxygen transport chain needs to be targeted to treat fatigue in patients with CKD.

Systematic review of the impact of erythropoiesis-stimulating agents on fatigue in dialysis patients

BACKGROUND

One of the cardinal symptoms of anemia in chronic kidney disease (CKD) patients is fatigue. Recently, results from Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT) raised questions about the role of erythropoiesis-stimulating agents (ESAs) in improving fatigue and the appropriate hemoglobin (Hb) target in anemic patients with CKD. These discussions should be considered with all available evidence to determine the level of benefits and risks associated with ESA therapy on fatigue among both early-stage CKD patients and end-stage renal disease patients on dialysis.

METHODS

The study was a systematic review of the literature on fatigue in adults on maintenance dialysis therapy. The requirement for inclusion in the review was the measurement of fatigue before and after ESA treatment. Outcomes that were assessed were fatigue as measured by the Kidney Disease Questionnaire, the 36-item Short-Form general health survey, the Nottingham Health Profile, the Profile of Mood States or the Functional Assessment of Chronic Illness Therapy-Fatigue scale. Several different measures of fatigue were used in the studies.

RESULTS

Fifteen articles met the criteria for inclusion, including 10 distinct studies and one extension study. There was one placebo-controlled randomized clinical trial (RCT) and one extension, five single-arm, three high versus low, one intravenous versus subcutaneous and one switch from epoetin alfa to darbepoetin alfa. The only placebo-controlled RCT found a 22-26% improvement in fatigue. Single-arm cohort studies demonstrated a reduction in fatigue after a substantial increase in Hb. Studies with a baseline Hb <10 g/dL and partial correction to a minimum Hb ≥ 10 g/dL showed an average improvement in fatigue of 34.6%. Studies with a baseline Hb ≥ 11 g/dL and full correction to a minimum Hb ≥ 12 g/dL showed an average improvement in fatigue of 5.5%, while studies with no change in Hb (either placebo or control group) showed a decline of 0.7% in fatigue outcomes.

CONCLUSION

Partial correction of anemia with ESA results in improvement of fatigue among patients on dialysis, most strikingly in those patients with baseline Hb levels <10 g/dL.

Fatigue in chronic dialysis patients

Fatigue is common in chronic hemodialysis (HD) patients and impacts on daily living, impairs significantly the quality of life, increases the risk of cardiovascular events and negatively influences survival. Although numerous social, demographic, clinical, and laboratory variables have been associated with fatigue, the causes of this symptom are often unclear. In the absence of an underlying, treatable disorder, the results of therapeutic intervention are typically frustrating. So far, none of the drugs tested can be recommended for preventing and treating fatigue in chronic HD patients. There is some evidence that exercise may significantly improve fatigue in dialysis patients; however, this requires confirmation through large, prospective, randomized studies.

Impact of fatigue on outcomes in the hemodialysis (HEMO) study

BACKGROUND

Fatigue is a common debilitating symptom in chronic kidney disease patients on maintenance hemodialysis. However, little is known about its pathogenesis and association with survival.

METHODS

This study examines the correlates and outcomes of fatigue among 1,798 hemodialysis patients enrolled in the HEMO study. Fatigue was assessed using the SF-36 vitality scale. Multivariable analysis was used to assess independent associations of demographic and clinical characteristics with baseline fatigue and longitudinal changes in fatigue. The association of fatigue with all-cause and cause-specific mortality and cardiac hospitalizations was also assessed.

RESULTS

Higher index of coexistent diseases (ICED) score, diabetes, non-African-American race, lower serum albumin, use of medications for sleep and poor sleep quality were found to be significantly associated with more fatigue at baseline. In longitudinal analyses, patients who were older, had been on dialysis longer, had higher ICED score, and reported using medications for sleep were more likely to experience worsening fatigue, whereas higher serum albumin was strongly associated with an improvement in level of fatigue. A 10-point increase in vitality score was associated with 10% increase in mean survival (p < 0.0001).

CONCLUSIONS

Demographic and clinical factors have significant associations with fatigue, which itself predicts mortality. Improving fatigue in the end-stage renal disease population may positively impact patient well-being and survival.