Sleep disorders in end-stage renal disease: ‘Markers of inadequate dialysis?’

Survival benefit of CPAP therapy among dialysis patients with obstructive sleep apnea

BACKGROUND AND HYPOTHESIS

We observed lower risk of all-cause mortally among continuous positive airway pressure (CPAP) users compared to those non-users using a large polysomnography (PSG) registry. However, the effect of CPAP on mortality risk has not been examined in dialysis patents.

METHODS

We studied 9841 patients with PSG performed from September 1990 to 2010 in Nakamura clinic, Okinawa. Among them, we found 195 dialysis patients: 16 (1.0%) dialysis patients with apnea hypopnea index (AHI) < 5/hour in 1665 subjects and 179 (2.2%) in 8176 obstructive sleep apnea (OSA) patients. CPAP users were defined as patients who had been on CPAP for more than one month. Patients qualified and eligible for CPAP but refused were assigned as CPAP non-users. The median observation was 6.6 years. Mortality rates were compared between CPAP users and non-users using multivariate logistic analysis adjusted for age, sex, body mass index (BMI), AHI and medical history.

RESULTS

Among OSA dialysis patients (men 127, women 37), 116 (2.6%) were CPAP users and 48 (2.3%) were CPAP non-users. The number of deaths was 52 (29 CPAP users and 23 (CPAP non-users) during follow-up. The death rate was 25.0% for CPAP users and 47.9% for non-users. CPAP users showed better survival; hazard ratio (HR) 0.47 and 95% confidence interval (CI) of 0.27-0.81 (P = 0.007).

CONCLUSION

Dialysis patients with OSA showed better survival rates with the use of CPAP. Screening for OSA is recommended if patients complain of sleep problems, such as insomnia, daytime sleepiness, headache, and fatigue.

Sleep disturbances in adults with chronic kidney disease: an umbrella review

BACKGROUND

This umbrella review aimed to synthesise the existing evidence on sleep disturbances and sleep disorders in the adult chronic kidney disease (CKD) population.

METHODS

A systematic search across five electronic databases. Reviews were grouped according to aspects of sleep and the focus of the review. The JBI critical appraisal checklist was used for quality assessment, and Preferred Reporting Items for Overviews of Reviews (PRIOR) guideline was used for reporting. The protocol was registered in the international registry PROSPERO (CRD42024527039).

RESULTS

We identified 50 reviews covering three main aspects of sleep (sleep apnoea, restless legs syndrome and other sleep disturbances) across five focus areas (prevalence, interventions, health outcomes, determinants of sleep and patient experience). Most reviews reported on sleep disturbances (72%, 36 reviews) and focused on interventions (58%, 29 reviews). In contrast, evidence on sleep determinants and patient experience was limited. A high prevalence of sleep apnoea (49%), restless legs syndrome (27.2%) and other sleep disturbances (55%) was reported. Non-pharmacological interventions, including aromatherapy, dialysis, muscle relaxation, yoga, music, and nurse-led management, were found to improve sleep. However, this evidence was based on a single meta-analysis with few primary studies.

CONCLUSIONS

Despite the growing number of reviews on interventions to improve sleep, the evidence for their effectiveness is limited by the small number of primary studies and the high degree of overlap between reviews. Further research is needed to identify effective interventions. Additionally, qualitative studies exploring patients' perspectives on sleep are essential, as evidence in this area remains scarce.

Sleep quality in middle-aged and elderly hemodialysis patients: Impact of a structured nursing intervention program

BACKGROUND

Poor sleep quality is common among hemodialysis patients and can significantly impact their well-being. This study aimed to evaluate the effectiveness of a structured nursing intervention program in improving sleep quality in middle-aged and elderly hemodialysis patients.

AIM

To evaluate the impact of nursing intervention on sleep quality in hemodialysis patients.

METHODS

This cross-sectional study was conducted in a tertiary hospital, the First Affiliated Hospital of Nanchang University, in 2023. This study included 105 middle-aged and elderly hemodialysis patients aged ≥ 45 years who underwent maintenance hemodialysis for at least 3 mo, utilizing the Pittsburgh Sleep Quality Index (PSQI) to identify poor sleepers. Those identified underwent a 12-wk nursing intervention program focusing on education, relaxation techniques, and counseling. Post-intervention, sleep quality was reassessed using the PSQI.

RESULTS

The study found that 68.6% of hemodialysis patients were poor sleepers. Following the 12-wk nursing intervention program, there was a significant decrease in the mean global PSQI score from 8.9 ± 3.2 to 5.1 ± 2.7 (P < 0.001), indicating improved sleep quality. This demonstrated the effectiveness of the structured nursing intervention in enhancing sleep quality for middle-aged and elderly hemodialysis patients.

CONCLUSION

The structured nursing intervention program focusing on sleep hygiene education, relaxation techniques, and counseling effectively improved sleep quality among middle-aged and elderly hemodialysis patients. The significant decrease in the mean global PSQI score post-intervention indicates the positive impact of tailored nursing interventions in addressing poor sleep quality in this patient population. These findings emphasize the importance of implementing targeted nursing interventions to enhance the quality of life for hemodialysis patients by addressing the prevalent issue of poor sleep quality.

Lower urinary tract symptoms among male patients on hemodialysis: Prospective and multi-central cross-sectional study

Background

Lower urinary tract symptoms are common and can significantly impact quality of life, especially in men with co-morbidities and end-stage renal disease. The presence of lower urinary tract symptoms affect the quality of life of patients on hemodialysis.

Objectives

The purpose of this study is assessing the presence and severity of lower urinary tract symptoms among male patients on hemodialysis. Factors that may exacerbate lower urinary tract symptoms were assessed and studied. The impact of lower urinary tract symptoms on quality of life was also identified.

Methods

A prospective, multi-central, and cross-sectional study of male patients on hemodialysis was conducted. Demographics, clinical data, and core lower urinary tract symptoms score questionnaire were all collected. A correlation has been made between all variables.

Results

One hundred forty-five patients were enrolled. Eighty-seven percent of hemodialysis patients had at least one storage symptom, and 85% had at least one voiding symptom. The prevalence of storage symptoms (frequency, nocturia, urgency, and urgency incontinence) was found to be 3%, 70%, 44%, and 12%, respectively. The voiding symptoms were mainly weak stream, straining, and incomplete emptying, which were found in 60%, 43%, and 36%, respectively. Fifteen percent of the cohort had a negatively significant impact on their quality of life. The absence of voiding symptoms was statistically linked to a better quality of life (p < 0.05). Hemodialysis patients who are over 60 years old, smokers, or obese were found to be significantly more likely to report storage symptoms (18%, 9%, and 79%, respectively; p < 0.05). Bladder pain was significantly correlated to the dialysis duration of more than 24 months (p < 0.05).

Conclusion

Storage and voiding lower urinary tract symptoms are common among hemodialysis male patients with a minor impact on their quality of life. Age, smoking, and obesity are major risks of exaggerating such symptoms.

Effectiveness of Combined Hemodialysis-Hemadsorption Therapy in Improving Uremic Toxin Clearance, Inflammatory Markers, and Symptoms in Maintenance Hemodialysis Patients

INTRODUCTION

Combined hemodialysis (HD) and hemadsorption (HA) therapy has shown the highest clearance rates for middle and large-sized uremic toxin molecules and reduced mortality rates among maintenance HD (MHD) patients. This study aimed to investigate the effectiveness of combined HD and HA therapy in patients undergoing MHD.

METHODS

Forty patients with end-stage renal disease (ESRD) were divided into three groups: HD only (14), HD + biweekly HA (14), and HD + weekly HA (12). The duration of the study was 8 weeks. Uremic toxins (β2-microglobulin, leptin, parathyroid hormone), inflammatory markers (interleukin-6, C-reactive protein), and symptoms (appetite, pruritus, sleep quality) were assessed before the start and at the completion of therapy. Changes in the parameters were compared between the three groups. Mean differences of parameters in each group were also compared between before and after therapy.

RESULTS

Decrease in BUN level (-61.34 mg/dL [95% CI: -71.33 to -51.34], p < 0.0001) and pruritus score (-3.93 [95% CI: -6.89 to -0.97], p = 0.013) was significantly larger in HD + biweekly HA group compared to the others. Only HD + biweekly HA group showed significant reductions in CRP level (-0.10 mg/L [95%: -0.18 to -0.01], p = 0.034), VAS appetite score (10.43 [95% CI: 4.99-15.87], p = 0.001), and pruritus score (-3.93 [95% CI: -6.89 to -0.97], p = 0.013) after therapy. Both HD + biweekly HA (-2.79 [95% CI: -4.97 to -0.60], p = 0.016) and HD + weekly HA group (-2.33 [95% CI: -4.59 to -0.08], p = 0.044) exhibited a significant improvement in sleep quality score after therapy.

CONCLUSIONS

HD combined with a biweekly HA is associated with a greater reduction in BUN level and better improvement of pruritus in ESRD patients compared to HD alone. HD + biweekly HA can significantly reduce CRP levels, alleviate pruritus, improve appetite, and enhance sleep quality.

Demographic and clinical risk factors for diagnosis of sleep disorders in ESRD patients

BACKGROUND

Sleep disturbances in patients with end-stage renal disease (ESRD) are common and more prevalent than in the general population. This study aims to assess the demographic and clinical risk factors for the diagnosis of sleep disorders in ESRD patients.

METHODS

This study is a retrospective analysis of the United States Renal Data System (USRDS) to evaluate risk factors for the diagnosis of sleep disorders, including hypersomnolence, insomnia, restless leg syndrome (RLS), or obstructive or central sleep apnea (OSA/CSA). All ESRD subjects enrolled in the USRDS between 2004-2015 were eligible for inclusion. The risk factors analyzed were age, race, sex, ethnicity, access type, dialysis modality, and the Charlson Comorbidity Index (CCI). All statistical analysis was performed using SAS 9.4, and statistical significance was assessed using an alpha level of 0.05. Descriptive statistics on all variables overall and by each sleep diagnosis were determined.

RESULTS

Increasing age, black race, other race, and Hispanic ethnicity were associated with decreased risk of each sleep diagnosis while CCI was associated with increased risk. Females were at increased risk of RLS and insomnia while males were at increased risk of OSA/CSA. Catheter and graft access decreased risk of RLS but increased risk of insomnia compared to AVF access. Catheter access increased risk of OSA/CSA compared to graft access. Hemodialysis increased risk of OSA/CSA compared to peritoneal dialysis.

CONCLUSIONS

Some ESRD patients are at an increased risk for diagnosis of sleep disorders based on age, race, sex, comorbid health conditions, and dialysis modality.

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.

History of Sleep Disorders in Chronic Kidney Disease: First Approach

OBJECTIVES

In this study, we examined the history of sleep disorders in chronic kidney disease, 60 years after the advent of hemodialysis and renal transplant of genetically nonrelated organs, which have spurred a critical mass of data.

MATERIALS AND METHODS

We analyzed selected literature on sleep disorders in chronic kidney disease from 1959 onward.

RESULTS

Sleep disturbances are present in the general population. They cause loss of renal function and progressive nephron loss. Insomnia, sleep apnea, restless leg syndrome, and periodic limb movements represent sleep disturbances in chronic kidney disease. These symptoms manifest early in chronic kidney disease and are a rule in patients on dialysis and kidney transplant recipients. Sleep disturbances cause fatigue, excessive daily sleepiness, impaired daytime function, impaired health-related quality of life, increased morbidity, and increased mortality.

CONCLUSIONS

Sleep disorders affect most patients with chronic kidney disease. No ascertained pharmacological therapy exists, and even a successful transplant does not totally restore a refreshing sleep. Longer nocturnal hemodialysis is of benefit. Sleep apnea may be cured with continuous positive airway pressure.

Nurse-based educational interventions in patients with peritoneal dialysis: A systematic review and meta-analysis

Background

Peritoneal dialysis (PD) is a major renal replacement therapy modality for patients with end-stage kidney disease (ESKD) worldwide. As poor self-care of PD patients could lead to serious complications, including peritonitis, exit-site infection, technique failure, and death; several nurse-based educational interventions have been introduced. However, these interventions varied and have been supported by small-scale studies so the effectiveness of nurse-based educational interventions on clinical outcomes of PD patients has been inconclusive.

Objectives

To evaluate the effectiveness of nurse-based education interventions in PD patients.

Design

A systematic review and meta-analysis of Randomized Controlled Trials (RCTs).

Methods

We performed a systematic search using PubMed, Embase, and CENTRAL up to December 31, 2021. Selection criteria included Randomized Controlled Trials (RCTs) relevant to nurse-based education interventions in ESKD patients with PD in the English language. The meta-analyses were conducted using a random-effects model to evaluate the summary outcomes of peritonitis, PD-related infection, mortality, transfer to hemodialysis, and quality of life (QoL).

Results

From 9,816 potential studies, 71 theme-related abstracts were selected for further full-text articles screening against eligibility criteria. As a result, eleven studies (1,506 PD patients in seven countries) were included in our systematic review. Of eleven studies, eight studies (1,363 PD patients in five countries) were included in the meta-analysis. Sleep QoL in the intervention group was statistically significantly higher than control (mean difference = 12.76, 95% confidence intervals 5.26-20.27). There was no difference between intervention and control groups on peritonitis, PD-related infection, HD transfer, and overall QoL.

Conclusions

Nurse-based educational interventions could help reduce some PD complications, of which only the sleep QoL showed statistically significant improvement. High-quality evidence on the nurse-based educational interventions was limited and more RCTs are needed to provide more robust outcomes.

Tweetable abstract

Nurse-based educational interventions showed promising sleep quality improvement and potential peritonitis risk reduction among PD patients.

The Biological Roles of Urea: A Review of Preclinical Studies

Urea is an organic compound that has been reported to be effective against many pathological conditions. However, many other studies have reported the toxic effects of urea. These controversies on the biological roles of urea remain unresolved. This review aims to evaluate the biological roles of urea in experimental animals from data published in peer-reviewed journals. A PubMed search was conducted using the phrase, "urea application in experimental animals." A total of 13 publications that met the inclusion criteria were evaluated. The test substance, animal model, number of animals, doses, duration of treatment, and effects were recorded. Regarding the toxic effect, urea caused decreased excretion of other nitrogenous compounds, increased oxidative stress, decreased insulin, and impairment of beta-cell glycolysis. Furthermore, it caused endothelial dysfunction, loss of synapsis, and decreased olfaction. Regarding the therapeutic effects, urea caused increased growth, increased digestion, and decreased hepatic dysfunction. It also induced apoptosis of tumor cells and exerted neuroprotective properties. Products containing urea should be used with caution, especially in individuals with symptoms of chronic kidney disease. However, more studies are needed to elucidate the mechanisms of its therapeutic effects.

Factors affecting quality of daytime and nighttime sleep among dialysis patients: A single center experience

BACKGROUND

Hemodialysis is the most common treatment modality for patients with chronic kidney disease (CKD). Excessive daytime sleepiness and poor nighttime sleep is a common problem among these patients. Patients on maintenance hemodialysis (MHD) are regularly exposed to impaired fluid balance, which may cause overhydration of varying degree. However, the role of hydration status in sleep quality has not been explored in Indian setting. Hence, this study was undertaken to assess the factors affecting sleep quality among patients on MHD in a tertiary care hospital.

MATERIAL AND METHODS

Patients (N = 55) were enrolled if they aged above18 years, on MHD for at least 3 months, and gave consent. The daytime sleep quality was assessed using Epworth Sleepiness Scale (ESS) and Insomnia Severity Index (ISI). The data were analyzed using SPSS version 20 and STATA software.

RESULTS

The mean age of the patients was 40.4 ± 14.7 years. The prevalence rate of predialysis fluid overload was 85.4%. The median ESS score was 7 and ISI score was 3 indicating normal daytime sleep and not significant insomnia. Multivariate regression with variables adjustment showed that interdialytic weight gain (P = 0.33), tingling sensation (P = 0.36) and numbness (P = 0.35) were significant predictive factors for quality of sleep.

CONCLUSION

The major factors affecting sleep quality were numbness, tingling sensation, and interdialytic weight gain. Fluid overload did not play any role in sleep quality. Another study may be carried out on assessment of pattern, duration, quality of sleep in multiple dialysis sessions, and effect of optimizing fluid status on the sleep parameters.

Insomnia and Poor Sleep in CKD: A Systematic Review and Meta-analysis

Rationale & Objective

Poor sleep quality and insomnia are pervasive among patients with advanced chronic kidney disease (CKD); however, these health issues have not been systematically evaluated.

Study Design

Systematic review and meta-analysis.

Setting & Study Populations

Adult patients with CKD not receiving kidney replacement therapy (KRT), as well as adults receiving KRT, including hemodialysis, peritoneal dialysis, and kidney transplantation.

Selection Criteria for Studies

A systematic literature search using PubMed, Embase, and PsycNET, was conducted for articles published between January 1, 1990, and September 28, 2018.

Data Extraction

Data on the prevalences of poor sleep quality and insomnia in patients with CKD, including those receiving and not receiving KRT, were extracted.

Analytical Approach

Pooled prevalences were estimated using a random-effects meta-analysis and were stratified according to age, CKD stage, World Health Organization region, risk of bias, Pittsburgh Sleep Quality Index score, and the different criteria for insomnia that were used at diagnosis.

Results

Of 3,708 articles, 93 were selected, and significant methodological heterogeneity was present. The pooled prevalences of poor sleep quality for CKD without KRT, hemodialysis, peritoneal dialysis, and kidney transplantation were 59% (95% CI, 44%-73%), 68% (95% CI, 64%-73%), 67% (95% CI, 44%-86%), and 46% (95% CI, 34%-59%), respectively. The corresponding prevalences of insomnia were 48% (95% CI, 30%-67%), 46% (95% CI, 39%-54%), 61% (95% CI, 41%-79%), and 26% (95% CI, 9%-49%), respectively. Insomnia was significantly more prevalent among patients aged 51-60 years and those aged >60 years than among those aged <50 years. The prevalence of insomnia in the European region was the lowest of all World Health Organization regions.

Limitations

High interstudy heterogeneity.

Conclusions

Approximately half of the patients with advanced CKD had poor sleep quality or insomnia, and the prevalence was even higher among those who received KRT. Kidney transplantation may reduce the burden of poor sleep quality and insomnia.

The impact of quality of life measured by WHOQOL-BREF on mortality in maintenance hemodialysis patients: a single center retrospective cross-sectional study

BACKGRUOUND

Several previous studies have reported that quality of life (QoL) in hemodialysis patients affects mortality. However, the 36-item Short Form Health Survey, which has been used mainly in previous studies, is complicated in terms of questionnaire composition and interpretation. This study aimed to identify the impact of QoL on mortality in hemodialysis patients using an easier and simpler diagnostic tool.

METHODS

This retrospective study included 160 hemodialysis patients. QoL was evaluated using the World Health Organization Quality of Life Questionnaire-Brief version (WHOQOL-BREF). Psychosocial factors were evaluated using the Hospital Anxiety and Depression Scale, Multidimensional Scale of Perceived Social Support, Montreal Cognitive Assessment, and Pittsburgh Sleep Quality Index. We also evaluated medical factors, such as dialysis adequacy and laboratory results.

RESULTS

The mean hemodialysis vintage was 70.7±38.0 months. The proportion of patients who were elderly was higher in the mortality group than in the surviving group, and the Charlson Comorbidity Index score was also higher in the former group. Of the four domains of the WHOQOL-BREF, the physical health and psychological scores of the mortality group were significantly lower than those of the survival group. When the score in the physical health domain or psychological domain was ≤10, the 10-year mortality rate after hemodialysis initiation increased by approximately 2.3- and 2-fold, respectively.

CONCLUSION

QoL may have a significant effect on mortality in patients undergoing hemodialysis. The WHOQOL-BREF is an instrument that can measure QoL relatively easily and can be used to improve the long-term prognosis of patients undergoing hemodialysis.

Subjective Assessment of Sleep Quality and Excessive Daytime Sleepiness in Conventional Hemodialysis Population: A Single-Center Experience

Introduction

Sleep disturbances are common in patients with end-stage kidney disease on hemodialysis (hemodialysis population: HDP). Higher rates of primary sleep disorders, demographic characteristics, metabolic abnormalities, and the efficacy of treatment place HDP at higher risk. The pattern observed is delayed onset of sleep, frequent awakening episodes, insomnia, sleep apnoea, excessive daytime sleepiness, restless leg syndrome, abnormal limb movements, pain in limbs, confusion, and nightmares. Two commonly used subjective assessment scores are the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality and the Epworth Sleepiness Scale (ESS) to assess excessive daytime sleepiness.

Objective

Subjective assessment of sleep using PSQI and ESS scores in HDP and correlation with clinical and demographic characteristics.

Patients and Methods

A cross-sectional descriptive study of 148 patients with ESKD undergoing in-center hemodialysis. From June 2021 to October 2021 in Madurai medical college, Madurai, India. Subjective assessment with PSQI and ESS scores was done to identify sleep quality and daytime sleepiness, respectively.

Results

The median PSQI score was 6 (IQ:4–10), and as much as 68.24% scored >5 on the PSQI (poor sleepers). The median ESS score of the study participants was 4 (Iq range 3–7), and 19.59% had a total ESS score of more than 10 (excessive daytime sleepiness). The mean age of the participants was 44±14.5. Age more than 60, lower body mass index, unemployment, higher dialysis vintage of more than 2 years, lower hemoglobin, high calcium-phosphorus product are statistically significant for both PSQI and ESS scores.

Conclusion

The prevalence of poor sleep quality and excessive daytime sleepiness is high in HDP. Subjective assessment scores (PSQI and ESS) on the bedside are valuable tools in identifying sleep quality and EDS where objective assessment methods are not feasible and will help in the short time identification and management of sleep disturbances.

Sleep Patterns, Genetic Susceptibility, and Incident Chronic Kidney Disease: A Prospective Study of 370 671 Participants

Objectives

Unhealthy sleep behaviors may be potential risk factors for chronic kidney disease (CKD). We aimed to examine the associations of combined sleep patterns and genetic susceptibility with incident CKD.

Methods

This large-scale prospective cohort study included 370,671 participants without CKD at baseline (2006–2010) in UK Biobank data. Five sleep behaviors were made up of sleep duration, insomnia, snoring, chronotype, and daytime sleepiness according to questionnaire. Overall sleep patterns by summing the five scores were created. Weighted genetic risk score of kidney function was calculated. Incident CKD was recorded from death register, primary care, and hospital inpatient records. A subset of 41,130 individuals who participated both the initial assessment visit and follow-up visit (2012+) was also used.

Results

During a median follow-up of 10.6 years (about 3.9 million person-years), we documented 6,365 patients with incident CKD. In five sleep behaviors, sleep 7–8 h/day, free of insomnia and no frequent daytime sleepiness were independently associated with incident CKD, with a 12% (95%CI 7–16), 9% (3–14), 13% (9–18) lower risk, respectively. Compared to those with a sleep score of 0–1, participants with a score of 5 had a 21% (10–31%) lower risk of CKD. 17.1% of CKD in this cohort could be attributed to total poor sleep pattern. Participants with high genetic risk and intermediate or poor sleep pattern showed the highest risk of CKD (OR = 2.58, 95%CI 2.24–2.96; OR = 2.59, 95%CI 2.02–3.32, respectively), although there was no significant interaction between sleep patterns and genetic risk categories. Among individuals who participated both the initial assessment visit and follow-up visit, we found that the association between amelioration of sleep pattern and risk of CKD was significant after fully adjustment (OR = 0.60, 95%CI 0.36–0.99), compared with group of stable sleep pattern.

Conclusion

In this large prospective study, participants with a healthy sleep pattern was associated with a significant reduction of incident CKD risk no matter they had a high, intermediate, or low genetic risk.

Sleep pattern in a group of patients undergoing hemodialysis compared to control

Background

Patients with chronic kidney disease progress regularly every year to end-stage renal disease and have to undergo dialysis. Sleep disturbances have been reported to be frequent among patients receiving dialysis and contributing to the increase of their mortality and morbidity. The present research aimed to study the sleep pattern in hemodialysis patients and the risk factors associated. This cross-sectional case-control study included 40 subjects divided into 2 groups: 20 cases recruited from Ain Shams University Hospital’s dialysis unit and 20 in the control group with normal Pittsburgh Sleep Quality Index score matched for age and sex. Both groups were subjected to overnight polysomnography, and the cases group was assessed by the Pittsburgh Sleep Quality Index to determine their sleep quality.

Results

Nearly all polysomnographic parameters were significantly abnormal in the cases group except for sleep onset latency (P > 0.05), showing obstructive sleep apnea and periodic limb movement (P value 0.001). Based on their Pittsburgh Sleep Quality Index score, 30% were classified as good sleepers and 70% as bad sleepers. On comparing both groups, a significant difference was found. Poor sleepers had more worse sleep efficiency (62.9%), spent longer time during their sleep in stage 1 (26.6%) with shorter REM onset latency (113.5 ± 99.5), and had a longer duration of illness with lower serum creatinine level compared to good sleepers.

Conclusions

The prevalence of obstructive sleep apnea and periodic limb movement in hemodialysis patients is high; patients with longer time on dialysis are at more risk of sleep disorders, whereas hemoglobin levels, BUN, and other demographic factors do not seem to play a role in sleep disorder. Hence, patients on hemodialysis need to be screened for sleep disorders so as to improve their mortality and morbidity.

Emerging Treatments for Insomnia, Sleep Apnea, and Restless Leg Syndrome Among Dialysis Patients

Sleep disturbances are highly prevalent in patients with predialysis chronic kidney disease, end-stage kidney disease, and after a kidney transplant. They contribute to impairment in daily function and are associated with a high burden of physical and psychiatric symptoms, decreased quality of life, and increased morbidity and mortality. Sleep disturbances also may precipitate and accelerate kidney disease progression. They often evolve across the spectrum of kidney dysfunction and may persist or re-emerge in kidney transplant recipients. Investigation into the multifaceted and dynamic relationships between sleep disturbance and chronic kidney disease requires consideration of myriad contributors including the progression of kidney disease itself, the role of treatment via dialysis and kidney transplant, psychosocial factors, and underlying sleep disorders. Despite sleep disturbance being identified as a priority to address by patients and caregivers, sleep disorders including insomnia, sleep apnea, and restless leg syndrome remain under-recognized and undertreated, and innovation in their management remains modest. In this article, we review the relationships between sleep disturbance and kidney disease, the impact of sleep disturbance and sleep disorders on symptom burden and mental health, and treatment opportunities that may address overlapping symptoms across the spectrum of kidney disease and that could improve patient-related and clinical outcomes.

Prevalence of Depression and Sleep Disorders in Patients on Dialysis: A Cross-Sectional Study in Qatar

Patients with end-stage renal disease treated with dialysis have poor quality of life (QOL). Improving QOL in these patients with multiple comorbidities is a large challenge. We performed a cross-sectional study to evaluate the prevalence and associated factors of depression and sleep disorders in this population. Our primary aim was to evaluate QOL measures in dialysis patients in Qatar through a series of validated questionnaires mainly concerning depression and sleep disorders. Our secondary aim was to study the associations of age, sex, and comorbid conditions with the QOL measures. We hypothesized that end-stage renal disease (ESRD) patients on dialysis would have disturbed QOL due to both ESRD and dialysis and comorbidities. This prospective cross-sectional study included adult ESRD patients receiving either hemodialysis (HD) or peritoneal dialysis (PD) in the main tertiary dialysis unit in Qatar. We administered two surveys to evaluate depression (the Center for Epidemiologic Studies Depression Scale, http://www.bmedreport.com/archives/7139) and sleep disorders (the Pittsburgh Sleep Quality Index, https://www.sleep.pitt.edu/instruments/). We also reviewed patient demographics, comorbidities, and laboratory test results to evaluate any associated factors. We randomly studied 253 patients (62% on HD and 38% on PD). Overall, 48% of patients had depression, while 83.8% had sleep disorders. The PD had more poor sleepers than the HD group (89.1% versus (vs.) 75%, p=0.003). Most of our dialysis patients had poor sleep, but it was more significant in the elderly group 109 (90%) than in the young group 103 (78%) (p=0.009). Patients with diabetes mellitus (DM) had significantly more prevalence of poor sleep (131 (88.5%)) than those without DM (81 (77.1%), p=0.01). More female patients had depression than male patients (52% vs. 25%, p < 0.0001; odds ratio: 3.27 (95% confidence interval: 1.9-5.6), p < 0.0001). This is the first study in Qatar to evaluate depression and sleep disorders in patients on dialysis therapy.

REM sleep latency as an independent risk for cardiovascular events in hemodialysis patients

Background

Clinical significance of objectively measured poor sleep quality (SQ) as a risk for cardiovascular disease (CVD) events is not well known in hemodialysis (HD) patients, independently of sleep‐related breathing disorders (SRBDs) and sleep‐related metabolic abnormality.

Methods

The present study investigated baseline levels of objective sleep architecture together with obstructive sleep apnea (OSA) and central sleep apnea (CSA) using polysomnography in 88 HD study participants (M/F, 56/32; age 68.4 ± 9.3). Then, HD study participants were monitored for the occurrence of new‐onset CVD events with a median (range) follow‐up period of 33 (1–64) months.

Results

Among various measures of SQ, log (REM sleep latency [REM‐SL]) (interval between sleep‐onset and the first REM period) alone correlated in negative manners with triglycerides and non‐HDL‐C in all study participants and with fasting plasma glucose and HbA1c in study participants with type‐2 diabetes mellitus. In the Kaplan–Meier analysis, HD study participants with shorter REM‐SL had a significantly higher rate of new‐onset CVD events than those with longer REM‐SL. Stepwise logistic regression analysis and multivariate Cox proportional hazard regression analysis identified shorter REM‐SL as an independent risk factor for the development of a new‐onset CVD events, independent of mean oxygen saturation, log (AHI+1), log (central AHI+1), diabetes mellitus, CVD history, systolic blood pressure, statins use, and non‐HDL‐C.

Conclusions

The present study demonstrated that reduction of REM‐SL is independently associated with a higher rate of new‐onset of CVD events, independent of SRBDs (OSA and CSA) and diabetes mellitus, non‐HDL‐C in HD study participants, suggesting impaired SQ as a potential CVD risk factor, and thus a definite treatment target to protect against CVD specifically in HD study participants. REM‐SL might be a new risk factor of CVD events in HD patients with SRBDs.

The challenge of insomnia for patients on haemodialysis

Insomnia is common among patients on maintenance haemodialysis and may be exacerbated by the challenges of the COVID pandemic. However, data on the efficacy of insomnia interventions in this population are limited. Efforts are needed to address this important problem and increase access to insomnia interventions for patients on haemodialysis.

Sleep-HD trial: short and long-term effectiveness of existing insomnia therapies for patients undergoing hemodialysis

BACKGROUND

Patients with end-stage kidney disease (ESKD) treated with hemodialysis (HD) experience many distressing symptoms. One frequently reported symptom is insomnia. There are unique issues about HD treatments and schedules that disrupt regular sleep/wake routines and possibly contribute to the high severity of insomnia. Despite evidence for broad-ranging health effects of insomnia, very few clinical trials have tested the efficacy of treatments for HD patients. Cognitive-behavioral therapy for insomnia (CBT-I) is a recommended first-line therapy but largely inaccessible to HD patients in the United States, partly because they commit considerable amounts of time to thrice-weekly dialysis treatments. Another important reason could be the logistical and reimbursement challenges associated with providing behavioral health care at the dialysis center. CBT-I delivered by telehealth can overcome barriers to access, but its efficacy has never been rigorously tested for these patients. Pharmacotherapy is the most widely used treatment for insomnia; however, some drugs presently used are unsafe as they are associated with a higher risk for death for HD patients (benzodiazepines and zolpidem-like drugs). The efficacy and safety of other medications (trazodone) for the treatment of insomnia has never been tested for patients treated with HD.

METHODS

This trial tests the short- and long-term comparative effectiveness of 6-week treatment with telehealth CBT-I, trazodone, or medication placebo. This will be accomplished with a randomized controlled trial (RCT) in which 126 participants treated with HD in community-based dialysis facilities with chronic insomnia will be assigned 1:1:1 to telehealth CBT-I, trazodone, or medication placebo, respectively; short-term effectiveness of each treatment arm will be determined at the end of 6-weeks of treatment and long-term effectiveness at 25-weeks. The primary and secondary patient-reported outcomes will be assessed with computer-based telephone interviewing by research scientists blinded to treatment assignment; additional secondary outcomes will be assessed by participant interview and actigraphy.

DISCUSSION

This clinical RCT will provide the first evidence for the comparative effectiveness of two distinct approaches for treating chronic insomnia and other patient-reported outcomes for patients receiving maintenance HD.

TRIAL REGISTRATION

NCT03534284 May 23, 2018. SLEEP-HD Protocol Version: 1.3.4 (7/22/2020).

Prevalence and Risk Factors of Restless Legs Syndrome in Hemodialysis Patients

OBJECTIVE

The current study aimed to investigate the prevalence and risk factors of restless legs syndrome (RLS) in patients undergoing hemodialysis, as well as the mortality and risks of cardiovascular and cerebrovascular events.

METHODS

A total of 354 hemodialysis patients from four hospitals were enrolled. RLS was diagnosed using the International RLS Study Group (IRLSSG) criteria. The patients were evaluated face-to-face using the IRLSSG rating scale, Epworth Sleepiness Scale (ESS), Hamilton Anxiety Scale, Hamilton Depression Scale, and Pittsburgh Sleep Quality Index (PSQI). The patients were followed up for 9 months. Death was considered an endpoint event. The cardiovascular and cerebrovascular events were investigated.

RESULTS

The prevalence of RLS in hemodialysis patients was 40.7% and was associated with factors such as duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. The scores of the PSQI, ESS, and Hamilton Depression Scale in the RLS group were significantly higher than those in the non-RLS group (p < 0.05). During follow-ups, the incidence rate of cardiovascular diseases was 18.8% in the RLS group and 8.6% in the non-RLS group (p < 0.005). The IRLSSG rating scores were significantly higher in RLS patients with kidney transplantation failure compared with those without transplantation (p < 0.05).

CONCLUSION

The prevalence of RLS was high in hemodialysis patients. The risk factors of RLS included duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. RLS affected sleep quality and emotion and increased the risk of cardiovascular diseases in hemodialysis patients. RLS was more severe in patients with kidney transplantation failure compared with those without transplantation.

Sleep Quality in Iranian Hemodialysis Patients: A Systematic Review and Meta-analysis

Background:

Hemodialysis is a major therapeutic method for many chronic kidney disease patients that causes complications. One of these complications tends to be sleep disorders. This study was performed through systematic review and meta-analysis to determine the prevalence of low sleep quality in hemodialysis patients in Iran.

Materials and Methods:

Journal papers written in English and Persian searched from January 2000 to July 2018 were selected. The search keywords included (Prevalence OR Epidemiology) AND (hemorenodialysis OR hemodialysate OR 'intermittent chronic haemodialysis' OR 'intermittent chronic hemodialysis' OR 'intermittent haemodialysis' OR 'intermittent hemodialysis' OR 'kidney dialysis' OR 'renal dialysis') AND ('sleep problem' OR 'sleep disturbance' OR 'sleep disorder' OR 'sleep quality' OR 'chronobiology disorders' OR dyssomnia). To determine the pooled prevalence, the stochastic DerSimonian-Laird model was used, computing the effect size with its 95 per cent confidence interval. The main international electronic databases were Embase, PubMed/MEDLINE, ISI/Web of Science (WOS), Scopus, Psych INFO, and Iranian databases such as MagIran, SID and Irandoc. The data were analysed using the Stata (version 13.0).

Results:

After searching through the databases and other resources, 21 articles (7 in Persian and 14 in English language) were included. The overall prevalence of low sleep quality in dialysis patients was 75.30 per cent (95 per cent confidence interval, 70.08–82.50). The heterogeneity study showed moderate heterogeneity among studies (I² = 50.30 per cent, p < 0.05).

Conclusions:

The results of this study showed that the prevalence of low sleep quality in hemodialysis patients has become a common problem. Thus, patients' sleep quality need to be evaluated periodically.

Male Patients on Peritoneal Dialysis Have a Higher Risk of Sleep Apnea

STUDY OBJECTIVES

Peritoneal dialysis (PD) is a renal replacement therapy. One concern is whether patients on PD have a higher risk of sleep apnea (SA) due to intra-abdominal pressure increase and worsened ultrafiltration capacity. Despite this concern, to date, whether the risk of SA differs between PD, hemodialysis (HD), and groups without uremia is still uncertain.

METHODS

In this retrospective cohort study, data were obtained from the National Health Insurance Research Database of Taiwan. This database enrolled almost all patients on dialysis in the country. A total of 7,645 incident patients on PD and 38,225 incident patients on HD were enrolled. In addition, 38,225 patients without uremia were selected as the comparison cohort. Individuals were monitored for the occurrence of SA until 2013.

RESULTS

The results showed that patients on PD, regardless of sex, all had a higher risk of SA than non-dialysis groups. In contrast, the risk of SA in patients on HD was not significantly different from that of patients without uremia. We also compared the risk of SA between patients on PD and HD directly. The results showed that male patients on PD had a significantly higher risk of SA risk than male patients on HD. However, the risk of SA did not differ between female patients on PD and HD.

CONCLUSIONS

Patients on PD should receive regular SA assessments and that an increased awareness and a higher index of suspicion for SA should be maintained in these patients, especially male patients.

Social support as a mediator between sleep disturbances, depressive symptoms, and health-related quality of life in patients undergoing hemodialysis

Background

The hemodialysis regimen is an inevitable and mandatory treatment for patients with end-stage renal disease (ESRD). During the dialysis journey, patients may experience maladaptation in terms of sleep disturbances, depressive symptoms, and reduced health-related quality of life (HRQOL). Psychosocial resources such as social support may have beneficial influences on health outcomes, but studies have rarely analyzed the integrated relationships among risk factors which include pain, sleep disturbances, duration since diagnosis and various health outcomes in Taiwan. This study aimed to bridge this gap by investigating the relationships among related risk factors, social support, sleep disturbances, depressive symptoms, and HRQOL, which is composed of physical quality of life (PQOL) and mental quality of life (MQOL), in ESRD patients.

Method

A correlational design was used, and 178 patients aged 20 years or older were recruited via convenience sample. The relationships among the risk factors, the mediators, depressive symptoms, PQOL, and MQOL were analyzed using structural equation modeling.

Results

The findings showed that more than 70% of the participants reported poor sleep quality, and 32% reported depressive symptoms. When participants had greater pain and more sleep disorders, they were more likely to be depressed. When participants had more appraisal support; they had better PQOL and fewer depressive symptoms. Overall, the structural equation model explained 31.8% of the variance in self-reported depressive symptoms, 29.4% of the variance in PQOL, and 5.7% of the variance in MQOL. Moreover, appraisal support enhanced PQOL and reduced depressive symptoms by exerting its two mediating effects on sleep disturbances.

Conclusion

Our findings indicate that patients with ESRD who have more social support have better PQOL and MQOL and fewer depressive symptoms than those with less social support.

Additional hemoperfusion is associated with improved overall survival and self-reported sleep disturbance in patients on hemodialysis

Introduction:

Patients with maintenance hemodialysis have experienced long-standing sleep disturbance. In this study, we attempted to explore whether long-term hemoperfusion could improve sleep and increase the overall survival in hemodialysis patients.

Methods:

A total of 158 patients, who underwent routine hemodialysis, were assessed in this study. These patients were computer-matched into two groups, with one group including 80 patients with absolute hemodialysis and the other consisting of 78 cases with hemodialysis in combination with hemoperfusion. Hemoperfusion was performed 1–2 times biweekly, with each session lasting 2 h. Self-reported sleep disturbance was evaluated before and after the observational time (2-year period); sleep quality was measured using the Pittsburgh Sleep Quality Index.

Findings:

Using multivariate regression analyses, we found sleep duration was associated with age, diabetes, low income, pruritus, hyperphosphatemia, hypercalcemia, high parathyroid hormone, and hemoglobin ( P < 0.001). The overall survival rate of the hemodialysis in combination with hemoperfusion group was significantly higher than that of the absolute hemodialysis group ( P < 0.05) after adjusting for sex, age, and diabetes. A 2-year hemoperfusion therapy was associated with improved sleep disturbance and sleep efficiency; this was accompanied by an increase in nocturnal melatonin levels. Furthermore, there was a significant difference in the first hospitalization between the hemodialysis and hemodialysis in combination with hemoperfusion groups ( P < 0.01).

Discussion:

Our results indicated that hemoperfusion in combination with hemodialysis is associated with an increase in the overall survival and improved sleep disorders in hemodialysis patients.

Association between abnormal thalamic metabolites and sleep disturbance in patients with end-stage renal disease

Sleep disturbances are common in end-stage renal disease (ESRD) patients. However, the underlying neuropathological mechanisms are largely unclear. Previous studies have revealed the important role of the thalamus in the potential mechanisms of sleep disorders. We hypothesized that the sleep disturbances in ESRD patients may correspond to metabolic changes of thalamus and the uremic factors may have a vital contribution on these changes. We performed multi-voxel ¹H-MRS of bilateral thalami in 27 ESRD patients who currently receiving hemodialysis treatment and 21 age-matched healthy volunteers. ESRD patients underwent Pittsburgh Sleep Quality Index (PSQI) scale and restless legs syndrome (RLS) rating scale assessment. Laboratory blood tests including serum creatinine, serum urea, cystatin-C, serum parathyroid hormone (PTH), calcium and phosphorus levels, hemoglobin and hematocrit were performed in all ESRD patients close to the time of the MR examination. We found correlations among elevated PTH, higher PSQI score and RLS rating score in ESRD patients. ESRD patients displayed decreased N-acetylaspartate and creatine ratio (NAA/Cr) of thalami compared with controls. There were significantly negative correlation between NAA/Cr and serum PTH level or PSQI score. The metabolic changes of thalami played an important role in the neuropathological mechanisms of lower sleep quality in ESRD patients. Secondary hyperparathyroidism as one of the main uremia-related factors was closely related to abnormal metabolites of the thalamus in patients with ESRD, revealing the crosstalk procedure between renal impairment and brain function.

Exploring sleep disorders in patients with chronic kidney disease

Kidney disorders have been associated with a variety of sleep-related disorders. Therefore, researchers are placing greater emphasis on finding the role of chronic kidney disease (CKD) in the development of obstructive sleep apnea and restless legs syndrome. Unfortunately, the presence of other sleep-related disorders with CKDs and non-CKDs has not been investigated with the same clinical rigor. Recent studies have revealed that myriad of sleep disorders are associated with CKDs. Furthermore, there are a few non-CKD-related disorders that are associated with sleep disorders. In this narrative review, we provide a balanced view of the spectrum of sleep disorders (as identified in International Classification of Sleep disorders-3) related to different types of renal disorders prominently including but not exclusively limited to CKD.

Association between changes in quality of life and mortality in hemodialysis patients: results from the DOPPS

Background

Cross-sectional health-related quality of life (HR-QOL) measures are associated with mortality in hemodialysis (HD) patients. The impact of changes in HR-QOL on outcomes remains unclear. We describe the association of prior changes in HR-QOL with subsequent mortality among HD patients.

Methods

A total of 13 784 patients in the Dialysis Outcomes and Practice Patterns Study had more than one measurement of HR-QOL. The impact of changes between two measurements of the physical (PCS) and mental (MCS) component summary scores of the SF-12 on mortality was estimated with Cox regression.

Results

Mean age was 62 years (standard deviation: 14 years); 59% were male and 32% diabetic. Median time between HR-QOL measurements was 12 months [interquartile range (IQR): 11, 14]. Median initial PCS and MCS scores were 37.5 (IQR: 29.4, 46.2) and 46.4 (IQR: 37.2, 54.9); median changes in PCS and MCS scores were -0.2 (IQR: -5.5, 4.7) and -0.1 (IQR: -6.8, 5.9), respectively. The adjusted hazard ratio (HR) for a 5-point decline in HR-QOL score was 1.09 [95% confidence interval (CI): 1.06-1.12] for PCS and 1.05 (95% CI: 1.03-1.08) for MCS. Adjusting for the second QOL score, the change was not associated with mortality: HR = 1.01 (95% CI: 0.98-1.05) for delta PCS and 1.01 (95% CI: 0.98-1.03) for delta MCS. Categorizing the first and second scores as predictors, only the second PCS or MCS score was associated with mortality.

Conclusions

In our study, only the most recent HR-QOL score was associated with mortality. Hence, the predictive power of a measurement of HR-QOL is not affected by changes in HR-QOL prior to that measurement; more frequent HR-QOL measurements are needed to improve the prediction of outcomes in HD. Further studies are needed to determine the optimal frequency and appropriate instrument to be used for serial measurements.

The Association of Sleep Duration and Quality with CKD Progression

Evidence suggests that sleep disorders are common in individuals with CKD, but the influence of sleep duration and quality on CKD progression is unknown. We examined the association of habitual sleep duration and quality with CKD progression in 431 Chronic Renal Insufficiency Cohort (CRIC) Study participants, of whom 48% were women and 50% had diabetes (mean age of 60 years old, mean eGFR =38 ml/min per 1.73 m², and median urine protein-to-creatinine ratio [UPCR] =0.20 g/g). We assessed sleep duration and quality by 5-7 days of wrist actigraphy and self-report. Primary outcomes were incident ESRD, eGFR slope, log-transformed UPCR slope, and all-cause death. Participants slept an average of 6.5 hours per night; mean sleep fragmentation was 21%. Over a median follow-up of 5 years, we observed 70 ESRD events and 48 deaths. In adjusted analyses, greater sleep fragmentation associated with increased ESRD risk (hazard ratio, 1.04; 95% confidence interval, 1.01 to 1.07 per 1% increase in fragmentation). In adjusted mixed effects regression models, shorter sleep duration (per hour less) and greater sleep fragmentation (per 1% more) each associated with greater eGFR decline (-1.12 and -0.18 ml/min per 1.73 m² per year, respectively; P=0.02 and P<0.01, respectively) and greater log UPCR slope (0.06/yr and 0.01/yr, respectively; P=0.02 and P<0.001, respectively). Self-reported daytime sleepiness associated with increased risk for all-cause death (hazard ratio, 1.11; 95% confidence interval, 1.02 to 1.20 per one-point increase in the Epworth Sleepiness Scale score). These findings suggest that short and poor-quality sleep are unrecognized risk factors for CKD progression.

Hypoxia: The Force that Drives Chronic Kidney Disease

In the United States the prevalence of end-stage renal disease (ESRD) reached epidemic proportions in 2012 with over 600,000 patients being treated. The rates of ESRD among the elderly are disproportionally high. Consequently, as life expectancy increases and the baby-boom generation reaches retirement age, the already heavy burden imposed by ESRD on the US health care system is set to increase dramatically. ESRD represents the terminal stage of chronic kidney disease (CKD). A large body of evidence indicating that CKD is driven by renal tissue hypoxia has led to the development of therapeutic strategies that increase kidney oxygenation and the contention that chronic hypoxia is the final common pathway to end-stage renal failure. Numerous studies have demonstrated that one of the most potent means by which hypoxic conditions within the kidney produce CKD is by inducing a sustained inflammatory attack by infiltrating leukocytes. Indispensable to this attack is the acquisition by leukocytes of an adhesive phenotype. It was thought that this process resulted exclusively from leukocytes responding to cytokines released from ischemic renal endothelium. However, recently it has been demonstrated that leukocytes also become activated independent of the hypoxic response of endothelial cells. It was found that this endothelium-independent mechanism involves leukocytes directly sensing hypoxia and responding by transcriptional induction of the genes that encode the β2-integrin family of adhesion molecules. This induction likely maintains the long-term inflammation by which hypoxia drives the pathogenesis of CKD. Consequently, targeting these transcriptional mechanisms would appear to represent a promising new therapeutic strategy.

Sleep disordered breathing and cardiovascular risk in older patients initiating dialysis in the United States: a retrospective observational study using medicare data

Background

Sleep disordered breathing (SDB) such as sleep apnea is associated with cardiovascular disease in the general population. However, little is known about the cardiovascular risks of SDB in patients with end-stage renal disease (ESRD).

Methods

We identified Medicare fee-for-service beneficiaries aged ≥67 years initiating dialysis between 2004 and 2009. Outcomes of interest included all-cause mortality, incident myocardial infarction, ischemic stroke, and atrial fibrillation. We compared patients with and without diagnosed SDB using Cox proportional hazards regression.

Results

Between 2004 and 2009, 184,217 older patients developed ESRD, of whom 15,121 (8.2 %) were previously diagnosed with SDB. Patients diagnosed with SDB were younger, more likely to be male and Caucasian, less Medicaid eligible, had more non-Nephrology clinic visits, higher body mass index, and more comorbidity. In analyses adjusting for demographics and BMI, diagnosed SDB was associated with higher risk of death and atrial fibrillation, but not associated with myocardial infarction or ischemic stroke risk. After further adjustment for all baseline characteristics, diagnosed SDB was associated with slightly lower risks of death (hazard ratio [HR]: 0.93, 95 % confidence interval [CI]: 0.91–0.96), myocardial infarction (HR: 0.92, CI: 0.87–0.98), and ischemic stroke (HR: 0.90, 95 % CI: 0.82–0.98), and not associated with atrial fibrillation (HR: 1.02, CI: 0.98–1.07).

Conclusions

In older patients initiating dialysis in the U.S., diagnosed SDB was weakly associated with lower risks of death and important cardiovascular outcomes, thus adding to the list of established risk factors that are paradoxically associated with cardiovascular outcomes in the ESRD population.

Chronic Kidney Disease and Sleeping Disordered Breathing (SDB)

The outlines of the current manuscript are: 1. Re-establish the link between hypertension and SDB including prevalence, mechanism, and reversal of process (i.e. improvement in hypertension with improvement in SDB), why it is important-cardiovascular mortality with numbers. 2. Re-establish the link between hypertension and CKD including same points as above. Then ask if both CKD and SDB are combined, what happens to hypertension and cardiovascular mortality. 3. Lastly, talk about links between CKD and SDB on how each process feeds on the other and is a growing, common problem.

Altered sleep structure in patients with end-stage renal disease

OBJECTIVE

Although symptoms of sleep disturbances are widely recognized in end-stage renal disease (ESRD), the effect of uremia on sleep structure has not been well investigated. We hypothesized that compared to individuals without ESRD, those with ESRD would have altered sleep structure after controlling for the severity of sleep apnea (SA).

METHODS

We studied 57 ESRD patients (42 men) and 57 controls (46 men) who had undergone polysomnography. Control subjects were matched to the ESRD patients by age, body mass index (BMI), frequency of periodic leg movements per hour of sleep, and the frequency of apneas and hypopneas per hour of sleep [apnea-hypopnea index (AHI)].

RESULTS

The AHI and the percentage of patients with an AHI ≥15 were similar between ESRD and control groups. However, total (p = 0.002), rapid eye movement (REM) (p = 0.007), and non-REM (p = 0.022) sleep times were lower in ESRD patients than in the control group. In a multivariable analysis adjusted for age, sex, AHI, BMI, arousal index, and diabetes, ESRD remained independently associated with lower REM (p = 0.021) and total sleep times (p = 0.026).

CONCLUSION

ESRD is independently associated with reduced total and REM sleep times after controlling for the severity of SA and other variables. Although we could not identify the cause of reduced sleep times, these could be related to uremia or fluid overload or both. Accordingly, our data provide a strong rationale for examining the effects of intensifying dialysis on sleep structure in ESRD patients.

Restless Legs Syndrome: Associated Risk Factors in Hemodialysis Patients

Background:

Restless legs syndrome (RLS) may be associated with increased morbidity and mortality among end-stage renal disease (ESRD) patients; however, it is a disorder that is neglected in dialysis centers.

Objectives:

The goal of this study was to investigate the clinical factors associated with RLS among ESRD patients.

Patients and Methods:

This cross-sectional study was conducted on ESRD patients undergoing maintenance hemodialysis (HD) in three HD centers in Ahvaz city in Southwest Iran. Blood samples were obtained prior to a dialysis session to check the routine laboratory test results and assess the adequacy of dialysis. The presence of RLS was assessed by using the international RLS study group (IRLSSG) diagnostic criteria. The IRLSSG rating scale was also used to evaluate the severity of the RLS symptoms.

Results:

Of the 139 HD patients enrolled in this study, 60 were female (43.2%) and 79 were male (56.8%), with a mean age of 51.82 ± 13.31 years. The prevalence of RLS was 15.8% (22 patients), with 50% of them (11 patients) having severe or very severe symptoms. There was a significant relationship between RLS and longer durations of dialysis (P < 0.001). The mean level of serum ferritin was lower in patients without RLS, but it was not significant (P = 0.065). No significant differences were found according to age, gender, dialysis shifts, and hemoglobin (Hb) level among patients with and without RLS.

Conclusions:

We conclude that a significant percentage of ESRD patients undergoing maintenance HD have severe or very severe RLS symptoms. The presence of RLS is associated to longer durations of dialysis.

A Novel Application of a Biopsychosocial Theory in the Understanding of Disturbed Sleep before and after Kidney Transplantation

STUDY OBJECTIVES

Sleep and fatigue difficulties appear to be highly prevalent among individuals with end-stage renal disease and individuals who have received a kidney transplant. While there is some evidence of biopsychosocial factors predicting sleep disturbance in these populations, previous studies have relied on single time point retrospective measurements.

METHODS

The study utilized a 2-week prospective measurement approach, including one night of polysomnographic measurement, nightly sleep diaries, and self-report measures of health, sleep, and mood.

RESULTS

The current study demonstrates that a number of psychological and behavioral factors, including negative mood, quality of life, napping, and caffeine consumption, are related to sleep disturbance among pre- and post-kidney transplant patients. This study also found that many of these factors have different relationships with sleep disturbance when comparing pre- and post-kidney transplant patients.

CONCLUSIONS

These results suggest that such factors may be worthwhile areas for intervention in treating the symptoms of insomnia among pre- and post-transplant recipients. A nuanced approach to understanding sleep problems is likely warranted when conceptualizing insomnia and developing a treatment plan.

Obstructive Sleep Apnea and Kidney Disease: A Potential Bidirectional Relationship?

Chronic kidney disease (CKD) is associated with high mortality rates and heavy economic and social burdens. Nearly 10% of the United States population suffer from CKD, with fatal outcomes increased by 16-40 times even before reaching end-stage renal disease. The prevalence of obstructive sleep apnea (OSA) is between 3% and 7% in the general population, and has increased dramatically during the last 2 decades along with increased rates of obesity. However, the prevalence of OSA is much greater in patients with CKD. In addition, aggressive dialysis improves OSA. The current literature suggests a bidirectional association between CKD and OSA through a number of potential pathological mechanisms, which increase the possibility of both diseases being possible risk factors for each other. CKD may lead to OSA through a variety of mechanisms, including alterations in chemoreflex responsiveness, pharyngeal narrowing due to fluid overload, and accumulation of uremic toxins. It is also being increasingly recognized that OSA can also accelerate loss of kidney function. Moreover, animals exposed to intermittent hypoxia suffer histopathological renal damage. Potential mechanisms of OSA-associated renal dysfunction include renal hypoxia, hypertension, endothelial dysfunction, activation of the sympathetic nervous system, and increased oxidative stress.

Cheyne-Stokes respiration during sleep: mechanisms and potential interventions

Cheyne-Stokes respiration is characterized by a typical waxing and waning pattern in breathing amplitude, interspersed with central apnoeas or hypopnoeas. This article reviews current knowledge regarding Cheyne-Stokes respiration with a particular emphasis on the mechanisms and latest methods of intervention.

Prevalence of sleep disorders among ESRD patients

Sleep disorders are common among the patients undergoing dialysis in end stage renal disease (ESRD). Although variable, their prevalence has been reported to be higher when compared to the general population. The most frequently reported complaints are insomnia, restless leg syndrome (RLS), sleep-disordered breathing and excessive daytime sleepiness (EDS). The aim of this study was to assess the prevalence of sleep disorders in end stage renal disease patients on regular hemodialysis (group I with 30 patients) and CKD patients (group II with 30 patients) in comparison to 30 normal population (control group). In addition to laboratory investigations which included creatinine clearance using Cockroft and Gault formula, hemoglobin level (Hb), blood urea, serum creatinine, serum albumin, serum calcium and phosphorus and lipid profile, all subjects underwent one night of laboratory-based polysomnography (PSG) consisting of a standard montage of electroencephalography (EEG) (C3/A1 and O2/C3 or O1/C4), monopolar left and right electrooculography (EOG) referenced to the opposite mastoid, surface mentalis electromyography (EMG), respiratory airflow (measured by thermistor) and effort (piezoelectric sensors), electrocardiography (ECG), anterior tibialis EMG and pulse oximetry. For hemodialysis subjects, this study was performed on a night immediately following hemodialysis treatment. The results showed that patients on hemodialysis have sleep disorders, and that sleep disorders are common in group I and II than control group. The percentage of sleep disorders in hemodialysis patients were as follows: insomnia (69%), followed by obstructive sleep apnea syndrome OSAS (24%), RLS and periodic limb movement PLM (18%), nightmares (13%), EDS (12%), sleepwalking (2%), possible rapid eye movement behavior disorders RED (2%), possible narcolepsy (1.4%). While the percentage of sleep disorders in CKD patients were as follows: insomnia (54%), followed by RLS (19%), PLM (12%), OSAS (16%), nightmares (15%), EDS (15%), sleepwalking (4%), possible RBD (3%), possible narcolepsy (1%). There was inverse correlation between sleep disorders and Hb, albumin and creatinine clearance; also there was positive correlation between sleep disorder and phosphorus. We concluded that the sleep disorders are common in CKD patients either on conservative management or on regular hemodialysis. Treatment of anemia, hyperphosphatemia and hypoalbuminemia may improve sleep disorders among those patients.