Prevalence of sleep disturbances in chinese patients with end-stage renal failure on continuous ambulatory peritoneal dialysis

Sleep disorders in chronic kidney disease

Sleep disorders are highly prevalent in chronic kidney disease (CKD) but are often under-recognized. Restless legs syndrome, which is common in CKD owing to issues with dopamine metabolism and is exacerbated by iron deficiency and uraemia, can lead to poor sleep quality and increased daytime fatigue. Insomnia is also prevalent in CKD, particularly in patients requiring dialysis, with increased sleep latency and sleep fragmentation being reported. The cause of insomnia in CKD is multifactorial - poor sleep habits and frequent napping during dialysis, uraemia, medications and mood disorders have all been suggested as potential contributing factors. Sleep apnoea and CKD are also now recognized as having a bi-directional relationship. Sleep apnoea is a risk factor for accelerated progression of CKD, and fluid overload, which is associated with kidney failure, can lead to both obstructive and central sleep apnoea. The presence of obstructive sleep apnoea in CKD can exacerbate the already heightened cardiovascular morbidity and mortality in these patients, as well as leading to daytime fatigue and reduced quality of life. Increased awareness, timely diagnosis and appropriate therapeutic interventions are essential to reduce the negative impact of sleep disorders in patients with kidney disease.

Sleep Disorders and Dementia Risk in Older Patients with Kidney Failure: A Retrospective Cohort Study

Key Points

Older patients with kidney failure who are newly diagnosed with sleep disorders are at higher risk of developing any type of dementia, vascular dementia, and other/mixed types of dementia. For older patients with kidney failure who are diagnosed with obstructive sleep apnea, positive airway pressure therapy is an intervention that is associated with lower dementia risk.

Background

Community-dwelling older adults with sleep disorders are at higher risk of developing dementia. Greater than 50% of older patients with kidney failure experience sleep disorders, which may explain their high burden of dementia.

Methods

Among 216,158 patients (aged 66 years and older) with kidney failure (United States Renal Data System; 2008–2019), we estimated the risk of dementia (including subtypes) associated with sleep disorders using Cox proportional hazards models with propensity score weighting. We tested whether positive airway pressure (PAP) therapy was associated with reduced dementia risk among patients with obstructive sleep apnea (OSA).

Results

26.3% of patients were diagnosed with sleep disorders; these patients had a higher 5-year unadjusted cumulative incidence for any type of dementia (36.2% versus 32.3%; P < 0.001), vascular dementia (4.4% versus 3.7%; P < 0.001), and other/mixed dementia (29.3% versus 25.8%; P < 0.001). Higher risk of any type of dementia was identified in patients with insomnia (adjusted hazard ratio [aHR], 1.42; 95% confidence interval [CI], 1.34 to 1.51), sleep-related breathing disorders (SRBDs) (aHR, 1.20, 95% CI, 1.17 to 1.23), and other sleep disorders (aHR, 1.24; 95% CI, 1.11 to 1.39). Higher vascular dementia risk was observed in patients with insomnia (aHR, 1.43; 95% CI, 1.19 to 1.73) and SRBDs (aHR, 1.15; 95% CI, 1.07 to 1.24). Patients with SRBDs (aHR, 1.07; 95% CI, 1.00 to 1.15) were at higher risk of Alzheimer disease. Among patients with OSA, PAP therapy was associated with lower risk of any type of dementia (aHR, 0.82; 95% CI, 0.76 to 0.90) and vascular dementia (aHR, 0.65; 95% CI, 0.50 to 0.85).

Conclusions

Older patients with kidney failure and sleep disorders are at a higher risk of dementia. Sleep is an important modifiable factor that should be considered for targeted interventions to mitigate dementia risk in patients with kidney failure. For patients with OSA, PAP therapy is associated with lower dementia risk.

Restless Legs Syndrome in Chronic Kidney Disease- a Systematic Review

Objectives

The objective of this review is to provide updated information on the epidemiology, correlating factors and treatment of chronic kidney disease associated restless legs syndrome (CKD-A-RLS) in both adult and pediatric population.

Materials and Methods

We have reviewed the Medline search and Google Scholar search up to May 2022, using key words restless legs syndrome, chronic kidney disease and hemodialysis and kidney transplant. The reviewed articles were studied for epidemiology, correlating factors, as well as pharmacologic and non-pharmacologic treatment options.

Results

Our search revealed 175 articles, 111 were clinical trials or cross- sectional studies and 64 were review articles. All 111 articles were retrieved and studied in detail. Of these, 105 focused on adults and 6 on children. A majority of studies on dialysis patients reported a prevalence between 15-30%, which is notably higher than prevalence of RLS in general population (5-10%). The correlation between presence of CKD-A-RLS with age, gender, abnormalities of hemogram, iron, ferritin, serum lipids, electrolytes and parathyroid hormones were also reviewed. The results were inconsistent and controversial. Limited studies have reported on the treatment of CKD-A-RLS. Non-pharmacological treatment focused on the effect(s) of exercise, acupuncture, massage with different oils and infra-red light whereas, pharmacologic treatment options include the effects of dopaminergic drugs, Alpha2-Delta ligands (gabapentin and pregabalin), vitamins E and C, and intravenous iron infusion.

Conclusion

This updated review showed that RLS is two to three times more common in patients with CKD compared to the general population. More patients with CKD-A-RLS demonstrated increased mortality, increased incidence of cardiovascular accident, depression, insomnia and impaired quality of life than those with CKD without RLS. Dopaminergic drugs such as levodopa, ropinirole, pramipexole and rotigotine as well as calcium channel blockers (gabapentin and pregabalin) are helpful for treatment of RLS. High quality studies with these agents are currently underway and hopefully confirm the efficacy and practicality of using these drugs in CKD-A-RLS. Some studies have shown that aerobic exercise and massage with lavender oil can improve symptoms of CKD-A- RLS suggesting that these measures can be useful as adjunct therapy.

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.

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.

Factors Associated with Symptom Burden in Adults with Chronic Kidney Disease Undergoing Hemodialysis: A Prospective Study

People with end stage renal disease and undergoing hemodialysis experience a high symptom burden that impairs quality of life. This study aimed to assess the prevalence, dynamicity and determinants of symptom burden among middle-aged and older adult hemodialysis patients. A descriptive cross-sectional study together with a longitudinal assessment was used. A total of 118 and 102 hemodialysis patients were assessed at baseline and at a 6-month follow-up. Validated questionnaires were used to assess the symptom burden, stress, illness perception and social support. Multiple linear regression analysis was used to determine the factors associated with symptom burden. The median number of symptoms experienced was 21 (Interquartile Range (IQR); 18−23) and 19 (IQR; 13−22) at baseline and 6 months, respectively. Having elevated stress (β = 0.65, p ≤ 0.005) and illness perception (β = 0.21, p = 0.02) were significantly predicted symptom burden at baseline (F (4, 112) = 55.29, p < 0.005, R2 = 0.664). Stress (β = 0.28, p = 0.003), illness perception (β = 0.2, p = 0.03), poor social support (β = −0.22, p = 0.01) and low body weight (β = −0.19, p = 0.03) were the determinants for symptom burden at 6 months (F (5, 93) = 4.85, p ≤ 0.005, R2 = 0.24). Elevated stress, illness perception level, poor social support and low post-dialysis body weight were found to be determinants for symptom burden. Attention should be given to psychosocial factors of hemodialysis patients while conducting assessment and delivering care to patients.

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.

Changes in the Shape and Volume of Subcortical Structures in Patients With End-Stage Renal Disease

Introduction: End-stage renal disease (ESRD) typically causes changes in brain structure, and patients with ESRD often experience cognitive and sleep disorders. We aimed to assess the changes in the subcortical structure of patients with ESRD and how they are associated with cognitive and sleep disorders.

Methods: We involved 36 adult patients for maintenance hemodialysis and 35 age- and gender-matched control individuals. All participants underwent neuropsychological examination and 3T magnetic resonance imaging (MRI) to acquire T1 anatomical images. The laboratory blood tests were performed in all patients with ESRD close to the time of the MR examination. We used volumetric and vertex-wise shape analysis approaches to investigate the volumes of 14 subcortical structural (e.g., bilateral accumbens, amygdala, hippocampus, caudate, globus pallidus, putamen, and thalamus) abnormalities in the two groups. Analyses of partial correlations and shape correlations were performed in order to identify the associations between subcortical structure, cognition, and sleep quality in patients with ESRD.

Results: The volumetric analysis showed that compared with the healthy control group, patients with ESRD had less bilateral thalamus (left: p < 0.001; right: p < 0.001), bilateral accumbens (left: p < 0.001; right: p = 0.001), and right amygdala (p = 0.002) volumes. In the vertex-wise shape analysis, patients with ESRD had abnormal regional surface atrophy in the bilateral thalamus, right accumbens, left putamen, and bilateral caudate. Moreover, the Montreal Cognitive Assessment (MoCA) score was associated with volume reduction in the bilateral thalamus (left: Spearman ρ = 0.427, p = 0.009; right: ρ = 0.319, p = 0.018), and the Pittsburgh Sleep Quality Index (PSQI) score was associated with volume reduction in the bilateral accumbens (left: ρ = −0.546, p = 0.001; right: ρ = −0.544, p = 0.001). In vertex-wise shape correlation analysis, there was a positive significant correlation between regional shape deformations on the bilateral thalamus and MoCA score in patients with ESRD.

Conclusion: Our study suggested that patients with ESRD have subcortical structural atrophy, which is related to impaired cognitive performance and sleep disturbances. These findings may help to further understand the underlying neural mechanisms of brain changes in patients with ESRD.

Risk factors for sleep disorders in patients undergoing peritoneal dialysis

Sleep disorders in patients with end-stage renal disease are common but have rarely been reported in previous studies. Therefore, we examined the prevalence of sleep disorders and the risk factors for declining sleep quality in patients undergoing peritoneal dialysis (PD). A multicenter prospective cohort study was conducted at five PD centers across different provinces in China. A total of 449 patients who underwent PD between March to November 2013 were enrolled. Demographic data, laboratory indicators, presence of depression, and sleep assessment data were collected. Sleep questionnaires reflecting five categories of sleep disorders, namely, insomnia, restless legs syndrome, excessive daytime sleepiness, possible narcolepsy, and sleepwalking and nightmares, were administered at baseline and at 24 months postoperatively. Sleep disorders were diagnosed when a patient had at least one sleep problem. At baseline, 335 (74.6%) patients had at least one type of sleep disorder. Depression, diabetes mellitus (DM), and male were found to be associated with the presence of a sleep disorder. At follow-up, the prevalence of insomnia, restless legs syndrome, and excessive daytime sleepiness had significantly increased in 285 patients. Furthermore, cardiovascular disease (CVD) was found to be associated with the presence of sleep disorders in patients with one or more disorders at baseline, whereas a low serum albumin level was found to be associated with sleep disorders in patients without any sleep disorders at baseline. The prevalence of sleep disorders was relatively high among PD patients at baseline and increased afterthe2-year follow-up. Depression, DM, and male were associated with all sleep disorders at baseline. CVD was associated with the presence of a sleep disorder at baseline and worse sleep quality at the 2-year follow-up; whereas a low serum albumin level was associated with the risk of acquiring a sleep disorder at the 2-year follow-up among patients with normal sleep status at baseline.

Patient and caregiver perspectives on sleep in dialysis

Sleep disturbances are common among patients receiving dialysis and are associated with an increased risk of mortality and morbidity, and impaired quality of life. Despite being highly prioritised by patients, sleep problems remain under-diagnosed and inadequately managed. The aim of the present study was to describe the perspectives of patients receiving dialysis and their caregivers on sleep. We extracted qualitative data on sleep from 26 focus groups, two international Delphi surveys, and two consensus workshops involving 644 patients and caregivers from 86 countries as part of the Standardised Outcomes in Nephrology-Haemodialysis and -Peritoneal Dialysis (SONG-HD/SONG-PD) initiatives. The responses were from patients aged ≥18 years receiving haemodialysis or peritoneal dialysis, and their caregivers. We analysed the data using thematic analysis with five themes identified: constraining daily living (with subthemes of: battling intrusive tiredness, exacerbating debilitating conditions, broken and incapacitated); roadblocks in relationships (unable to meet family needs, antipathy due to misunderstanding, wreaking emotional havoc); burden on caregivers (stress on support persons, remaining alert to help); losing enjoyment (limiting social contact, disempowerment in life); and undermining mental resilience (aggravating low mood, diminishing coping skills, reducing functional ability). Sleep disturbances are exhausting for patients on dialysis and pervade all aspects of their lives including the ability to do daily tasks, and maintaining relationships, mental and emotional well-being. Better assessment and management of sleep problems in dialysis is needed, which may lead to improvements in overall health and quality of life.

Factors Associated with Sleep Disorders in Chinese Patients on Continuous Ambulatory Peritoneal Dialysis

Objective

This study aimed at identifying factors that are associated with sleep disorders in Chinese patients on continuous ambulatory peritoneal dialysis (CAPD).

Study Design

Questionnaire survey.

Setting

Renal dialysis unit of a tertiary-care hospital.

Patients

179 Chinese patients on CAPD.

Main Outcome Measures

The quantity and quality of sleep were compared between CAPD patients with and without self-reported sleep disorders. Demographic variables, personality traits, behavioral factors, somatic symptoms, and clinical parameters were correlated with the presence of sleep disorders.

Results

The mean age of the patients was 61 ± 12 years and the male-to-female ratio was 1:1.3. The mean duration of CAPD was 47 ± 42 months. 110 patients (61%) had self-reported sleep disorders. Among patients with self-reported sleep disorders, difficulty falling asleep was the most frequent complaint (74.5%), followed by frequent awakening (68%) and early morning waking (68%). The mean duration of sleep among these patients was 4.6 ± 2.2 hours, versus 7.3 ± 1.4 hours in patients without self-reported sleep disorders. Three personality traits (anxiety, worry, and sadness) and two somatic symptoms (bone pain and arthralgia) were the factors significantly associated with sleep disorders. Patients with sleep disorders also more frequently reported certain symptoms suggestive of sleep apnea. Demographic variables, behavioral factors ( e.g., caffeine or alcohol intake), and clinical parameters ( e.g., adequacy of dialysis, body mass index, hemoglobin, albumin, parathyroid hormone levels) did not differ between patients with and without sleep disorders.

Conclusions

Sleep disorders are prevalent among Chinese CAPD patients. Personality traits (anxiety, worry, and sadness) and somatic symptoms (bone pain and arthralgia) were the factors significantly associated with sleep disorders in this patient population. Behavioral factors, demographic variables, and clinical parameters did not appear to predict sleep disorders. Further studies evaluating the impact of various psychological factors on sleep disorders among CAPD patients are warranted.

Quality of Sleep and Psychosocial Factors for Patients Undergoing Peritoneal Dialysis

Objectives

Sleep disorders are common in end-stage renal disease patients. This study examined the relationship between self-reported quality of sleep (QoS) and certain psychosocial domains for patients on peritoneal dialysis (PD).

Methods

The study subjects included 190 PD patients from 7 urban dialysis clinics in Northern Taiwan, from whom we obtained biochemical parameters and demographic data. QoS, quality of life (QoL), religious/spiritual activity, and depression were assessed using the Pittsburgh Sleep Quality Index (PSQI) questionnaire, Medical Outcomes Study Short Form (SF-36) for QoL, the Royal Free Questionnaire, and the Beck Depression Inventory, respectively.

Results

The average PSQI score was 9.1 ± 4.1 and, in total, 85.8% of all patients were poor sleepers (global PSQI ≥ 5). There was no difference in age, gender, and mode or duration of PD between good and poor sleepers. Biochemical data did not differ between the two groups. Widowed patients experienced significantly poorer QoS than patients with other marital status (PSQI scores: 12.3 ± 4.9 vs 8.88 ± 4.0, p = 0.006). The percentage of patients that held a bachelor's degree or above was significantly higher in good sleepers (55.6% vs 29.4%, p = 0.008). The PSQI value correlated negatively with the QoL scale in both physical ( r = –0.295, p < 0.001) and mental domains ( r = –0.410, p < 0.001), and correlated positively with the depression scale ( r = 0.351, p < 0.001). There appeared to be no association between QoS and spiritual/religious activity ( r = –0.097, p = 0.223).

Conclusions

Psychosocial factors including depression, patients’ perceptions regarding QoL, marital status, and educational background correlated significantly to the subjective QoS for PD patients. When dealing with sleep disorders in PD patients, physicians should pay considerable attention to their psychosocial backgrounds.

Differential effects of age on quality of sleep and depression in patients receiving maintenance haemodialysis

BACKGROUND

Poor quality of sleep and depression are common and highly associated with each other in patients on haemodialysis. We aimed to investigate whether they share common risk factors and how age may influence their development.

METHODS

Cross-sectional observation study on 120 haemodialysis patients with quality of sleep and depression assessed by Pittsburgh Sleep Quality Index (PSQI) and Taiwanese Depression Questionnaire (TDQ), respectively.

RESULTS

The prevalence of poor quality of sleep and depression was 92.5% and 43.3%, respectively. PSQI scores were associated with age, gender, education and monthly income while TDQ scores were associated with low serum creatinine and albumin levels. Elderly patients at ages older than 65 had the highest average PSQI score (12.26 ± 4.35) than the young group at age 20-44 (8.25 ± 4.39) (P = 0.028) but the average TDQ scores were similar across three age groups. The proportion of those who had high PSQI scores was significantly higher in the elderly group (54.4%, P = 0.017) and the 44-65-years group (51.9%, P = 0.028) than the young group (16.7%). The proportion of those who reported normal quality of sleep was much lower in the elderly group (0.0%) than the other two groups (25.0%, P < 0.001 and 11.7%, P < 0.01). The proportions of those who had different ranges of TDQ scores did not show such a pattern of strong age dependence.

CONCLUSIONS

Poor quality of sleep in haemodialysis patients is associated with socio-economic factors while depression is more related to biochemistry indicators. A majority of older patients suffer very poor quality of sleep while depression appears equally severe and common across different age groups.

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.

Health-related quality of life in peritoneal dialysis patients: A narrative review

Health-related quality of life (HRQOL) is an important aspect of patients´ health that should be an integral part of the evaluation of patient-centered outcomes, not least because HRQOL associates with patients´ morbidity and mortality. This applies also to chronic kidney disease patients, including those dependent on renal replacement therapies, the type of which may influence patients´ perception of HRQOL. Several studies have addressed HRQOL in chronic kidney disease patients undergoing renal replacement therapies, especially transplanted patients and hemodialysis patients, while publications concerning peritoneal dialysis (PD) patients are scarcer. This review describes some of the methods used to assess HRQOL, factors influencing HRQOL in PD patients, HRQOL in PD vs hemodialysis, and the relation between HRQOL and patient outcomes. We conclude that assessment of HRQOL-often neglected at present-should be included as a standard measure of patient-centered outcomes and when monitoring the quality and effectiveness of renal care including PD treatment.

Auditory Deficits in Patients With Mild and Moderate Obstructive Sleep Apnea Syndrome: A Speech Syllable Evoked Auditory Brainstem Response Study

Objectives

The energy consumption process of cochlea and neural signal transduction along the auditory pathway are highly dependent on blood oxygen supply. At present, it is under debate on whether the obstructive sleep apnea syndrome (OSAS) would affect the auditory function since the patients suffer from low oxygen saturation. Moreover, it is difficult to detect the functional state of auditory in less severe stage of OSAS. Recently, speech-evoked auditory brainstem response (speech-ABR) has been reported to be a new electrophysiological tool in characterizing the auditory dysfunction. The aim of the present study is to evaluate the auditory processes in adult patients with mild and moderate OSAS by speech-ABR.

Methods

An experimental group of 31 patients with mild to moderate OSAS, and a control group without OSAS diagnosed by apnea hypopnea index in polysomnogram were recruited. All participants underwent otologic examinations and tests of pure-tone audiogram, distortion product otoacoustic emissions, click-evoked auditory brainstem response (click-ABR) and speech-ABR, respectively.

Results

The results of pure-tone audiogram, distortion product otoacoustic emissions, and click-ABR in OSAS group showed no significant differences compared with the control group (P>0.05). Speech-ABRs for OSAS participants and controls showed similar morphological waveforms and typical peak structures. There were significant group differences for the onset and offset transient peaks (P<0.05), where OSAS group had longer latencies for peak V (6.69± 0.33 ms vs. 6.39±0.23 ms), peak C (13.48±0.30 ms vs. 13.31±0.23 ms), and peak O (48.27±0.39 ms vs. 47.60± 0.40 ms) compared to the control group. The latency of these peaks showed significant correlations with apnea hypopnea index for peak V (r=0.37, P=0.040), peak C (r=0.36, P=0.045), as well as peak O (r=0.55, P=0.001).

Conclusion

These findings indicate that some auditory dysfunctions may be present in patients with mild and moderate OSAS, and the damages were aggravated with the severity of OSAS, which suggests that speech-ABR may be a potential biomarker in the diagnosis and evaluation at early stage of OSAS.

Restless Legs Syndrome in Dialysis Patients: Does the Dialysis Modality Influence Its Occurrence and Severity?

Background

Restless legs syndrome (RLS) is more prevalent in chronic kidney patients than in the general population, but it is often diagnosed late and its predictors are unknown.

Purpose

To diagnose RLS in a group of chronic kidney patients on dialysis, determine its frequency and severity, compare the prevalence and severity of the condition among dialytic modalities, and identify possible predictive factors in this population.

Methods

An observational and cross-sectional study with 326 patients who had been on dialysis for more than 3 months, 241 on hemodialysis (HD) and 85 on automatic peritoneal dialysis (APD), using the criteria established by the International Study Group on RLS for the diagnosis and the RLS Rating Scale to determine its severity.

Results

RLS was diagnosed in 19.3% of the patients, 52.4% with severe or very severe forms. Patients with and without RLS did not differ in clinical and demographic characteristics and dialytic modality; however, patients on APD presented higher RLS severity compared to the HD group.

Conclusions

RLS is frequent in dialysis patients and occurs predominantly in its most severe forms; the dialytic modality seems to have no influence on its occurrence; however, it is more severe in patients on APD.

Effect of Sedative-Hypnotic Medicines on Mortality in Peritoneal Dialysis Patients with Sleep Disorders: A Retrospective Cohort Study

BACKGROUND

Sedative-hypnotic medication is widely used among continuous ambulatory peritoneal dialysis (CAPD) patients with sleep disorders; however, its effect on mortality has rarely been investigated.

METHODS

Logistic regression was employed to identify factors associated with sedative-hypnotic medication, whose effect on mortality was evaluated by Cox proportional hazards models.

RESULTS

A total of 146 CAPD patients with sleep disorders were recruited, of which 46 patients (31.5%) used either benzodiazepines or zolpidem. Sedative-hypnotic medication was more frequently used by older patients and those with longer duration of CAPD therapy and there was no significant association between sedative-hypnotic medicines and all-cause mortality after adjusting for age, gender, diabetes, cardiovascular disease, and duration of CAPD.

CONCLUSION

Sedative-hypnotic medication was more often used by older patients and patients with a longer duration of CAPD. There was no association between these agents and all-cause mortality in CAPD patients with sleep disorders.

Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

Background

Objective of the study is to assess prevalence and survival among end stage renal disease patients with restless legs syndrome (RLS) within a national database (USRDS).

Methods

A case-control, retrospective analysis was performed. Differences in characteristics between the groups, RLS and those with no sleep disorder (NSD), were determined using χ2 tests. Cox proportional hazard regression was used to assess survival between those with RLS and propensity score matched controls.

Results

Cases of restless legs syndrome were defined as patients that had received an ICD-9 code of 333.94 at any point during their treatment (n = 372). RLS group demonstrated a significantly higher proportion of patients with major depressive disorder, dysthymic disorder, anxiety, depression, minor depressive disorder, and psychological disorder. The difference between the survival was not statistically significant in those without sleep disorder as compared to those with RLS (HR =1.16±0.14, p = 0.3).

Conclusions

True prevalence of RLS in dialysis patients can only be estimated if knowledge gap for care providers in diagnosis of RLS is addressed. RLS patients also have increased incidence of certain psychological disorders which needs to be addressed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0660-0) contains supplementary material, which is available to authorized users.

Restless leg syndrome in chronic hemodialysis patients in Mashhad hemodialysis centers

Introduction: Restless leg syndrome (RLS) is a sensory motor disorder. Patients with this syndrome have serious and uncontrollable desire to move their legs, which is mostly due to an uncomfortable feeling intensified when they are motionless. It may be a genetic disorder or secondary to iron deficiency, neurodegenerations, pregnancy, some drugs and severe kidney diseases.

Objectives: This study was designed to find out the prevalence and its risk factors of RLS in hemodialysis patients.

Patients and Methods: This multicenter cross-sectional study was done on 260 hemodialysis patients. The prevalence of RLS was measured using International Restless Legs Syndrome Study Group (IRLSSG)’s RLS Questionnaire (RLSQ). Potential risk factors for RLS including underlying cause of chronic renal failure, duration on dialysis, biochemical tests, dialysis adequacy, and erythropoietin and also venofer dosage in recent month and demographic data were also evaluated.

Results: The prevalence of RLS was 55% including 59.4% males and 40.6% females. Their mean age of RLS patients and their dialysis duration were significantly higher than other group (P<0.05). Their body mass index (BMI) and serum calcium were significantly higher (P<0.05). However erythropoietin dosage and serum hemoglobin level were lower in RLS patients (P<0.05). Significant predictors of RLS were history of diabetes mellitus (DM), hypertension (HTN), smoking (P<0.05). There was not significant relation between RLS and dialysis adequacy, serum intact parathyroid hormone (iPTH), urea, ferritin and venofer dosage (P>0.05).

Conclusion: According to the results, RLS is a common disorder in hemodialysis patients which can affect strongly on their life. So particular attention and sooner diagnosis of RLS in high risk patients for better management is necessary.

Sleep influences the immune response and the rejection process alters sleep pattern: Evidence from a skin allograft model in mice

INTRODUCTION

Sleep generally regulates immune functions in a supportive manner and can affect parameters that are directly involved in the rejection process.

STUDY OBJECTIVES

The first objective was to assess whether sleep deprivation (SD) or sleep restriction (SR) affects the allograft rejection process in mice. The second objective was to investigate whether the rejection process itself modulates the sleep pattern of allografted mice.

DESIGN

Adult BALB/c and C57BL/6J male mice were used as the donors and recipients, respectively, except for the syngeneic group (ISOTX), which received skin from mice of the same strain (C57BL/6J). The recipients were randomly assigned to either one of two control groups - TX (allogenic) or ISOTX (syngeneic) - which underwent stereotaxic surgery to enable sleep recording prior to the allograft but were not sleep deprived; one of two paradoxical sleep deprived groups - SDTX and TXSD - which underwent 72h of continuous SD either before or after the allograft respectively, and one of two sleep restricted groups - SRTX and TXSR - which underwent 21h of SD and 3h of sleep for 15days either before or after the allograft respectively.

INTERVENTIONS

The skin allograft was inspected daily to determine the survival time, expected as 8.0±0.4days in this transplant model under no treatment. The sleep pattern was controlled throughout the rejection process in the SD and SR groups. Draining lymph nodes, spleen, blood and skin grafts were harvested on the 5th day after transplantation for evaluation of the immune parameters related to allograft rejection.

MEASUREMENTS AND RESULTS

In the control groups, we observed a reduction in paradoxical sleep throughout the entire allograft rejection process. Acute and chronic experimental sleep loss in the SD and SR groups produced marked alterations in the immune response. Both SD and SR prolonged allograft survival compared to the non-sleep-deprived group. There were reductions in the following parameters involved in the allograft rejection under sleep loss: CD4⁺ and CD8⁺ T cell subpopulations in the peripheral lymph organs and spleen, circulating sIL-2R levels, graft-infiltrating CD4⁺ T cells and skin allograft global gene expression.

CONCLUSIONS

We provide, as far as we are aware, the first evidence in vivo that the immune response can alter the normal sleep pattern, and that sleep loss can conversely affect the immune response related to graft rejection.

Prevalence of restless legs syndrome in chronic kidney disease: a systematic review and meta-analysis of observational studies

INTRODUCTION

Nowadays prevalence of restless legs syndrome (RLS) in chronic kidney disease (CKD) patients was reported in many studies, while the results varied. The aim of our study was to investigate the prevalence of RLS in this population, considering different data collecting measures and diagnostic criteria.

METHODS

MEDLINE, Embase, PsycINFO, and Scopus databases were searched for relevant studies. We limited the analyses to studies using clinical interview or questionnaire for diagnosis. Univariate meta-regression analysis was preformed to assess the effects of the disease-related covariates on prevalence estimates. Comprehensive Meta-Analysis 2.0 was used to perform the meta-analysis.

RESULTS

Fifty-one studies were included in the analysis. Prevalence of RLS was varied by renal function and diagnostic methods. Overall prevalence in CKD populations was 24.2% (95%CI, 20.1-28.7). Pooled prevalence of RLS was higher in patients diagnosed by questionnaire than by clinical interview [26.2% (95%CI, 17.9-36.5) vs. 23.6% (95%CI, 19.6-28.1)]. When grouped by CKD setting, the prevalence was 28.4% (95%CI, 24.6-32.6) in dialysis patients, followed by early stages patients [9.9% (95%CI, 5.4-17.5)], and kidney transplant recipients [6.7% (95%CI, 5.6-7.8)].

CONCLUSIONS

Our meta-analysis suggested that more than one-quarter of CKD sufferers, especially those who were on dialysis, were plagued by RLS. Higher sensitivity of diagnostic criteria in interview may be valuable for timely treatment.

Lowest Oxyhemoglobin Saturation May Be an Independent Factor Influencing Auditory Function in Severe Obstructive Sleep Apnea

STUDY OBJECTIVES

The aims of this study were to determine if a correlation exists between the level of hypoxia induced by severe obstructive sleep apnea syndrome (OSAS) and the level of auditory dysfunction when verifying such a relationship using polysomnography (PSG).

METHODS

A retrospective review of 41 patients with severe OSAS was performed. Independent risk factors for hearing impairment included parameters of PSG, which were analyzed in two hearing groups at a level ≥ 40 decibels (dB).

RESULTS

Oxyhemoglobin saturation, especially the lowest oxyhemoglobin saturation level, showed lower thresholds in the hearing impairment group than in the control group (p = 0.039 at NREM stage; p = 0.029 at REM stage; p = 0.001 at total sleep stage). After adjusting for other risk factors, the sole variable that remained significant was lowest oxyhemoglobin saturation (total; p = 0.046). In the correlation analysis, a decreasing lowest oxyhemoglobin saturation (from all subjects, n = 41) correlated with a greater mean hearing threshold (R(2) = 0.297; p < 0.001).

CONCLUSION

Our results indicated that lowest oxyhemoglobin saturation in PSG is the only variable correlated with the hearing threshold. This finding could be predictive of possible hearing alternation in patients with severe OSAS.

COMMENTARY

A commentary on this article appears in this issue on page 641.

Sleep disorders and chronic kidney disease

Sleep disorders have a profound and well-documented impact on overall health and quality of life in the general population. In patients with chronic disease, sleep disorders are more prevalent, with an additional morbidity and mortality burden. The complex and dynamic relationship between sleep disorders and chronic kidney disease (CKD) remain relatively little investigated. This article presents an overview of sleep disorders in patients with CKD, with emphasis on relevant pathophysiologic underpinnings and clinical presentations. Evidence-based interventions will be discussed, in the context of individual sleep disorders, namely sleep apnea, insomnia, restless leg syndrome and excessive daytime sleepiness. Limitations of the current knowledge as well as future research directions will be highlighted, with a final discussion of different conceptual frameworks of the relationship between sleep disorders and CKD.

Objective and subjective sleep disorders in automated peritoneal dialysis

Background

Automated peritoneal dialysis (APD) is one of the fastest growing dialysis modalities. It is unknown whether sleep and mood are disturbed while performing repeated overnight exchanges.

Objectives

In this report, we aim to describe and compare the prevalence of sleep-disordered breathing (SDB), periodic limb movements (PLMS), poor sleep quality (SQ), and depression among APD patients compared with stages 3b–5 (estimated glomerular filtration rate ≤44 ml/min/1.73 m2) chronic kidney disease (CKD) and hemodialysis (HD) patients.

Design

This is a cross-sectional, descriptive study.

Setting

Study participants were recruited from outpatient nephrology clinics, local dialysis centers, and the Thomas E. Starzl Transplant Institute in Western Pennsylvania between April 2004 and July 2009.

Patients

There were 186 participants in this study including 22 APD patients, 89 CKD patients, and 75 HD patients.

Measurements

In-home polysomnography was performed and two questionnaires were completed, the Pittsburgh Sleep Quality Index (PSQI) and the Patient Health Questionnaire-9 (PHQ-9).

Methods

SDB and PLMS were quantified by in-home unattended polysomnography; poor SQ was defined by a score >5 on the PSQI, and the presence of moderate to severe depression was defined by a score >5 on the PHQ-9.

Results

The APD patients had a median age of 37.5 years, were predominantly female (72.7 %), and had a median body mass index (BMI) of 23.8 kg/m2. In univariate analyses, APD patients had significantly lower apnea-hypopnea index compared to HD patients by 12.2 points (likelihood ratio test p = 0.008) and revealed the least percent of TST with nocturnal hypoxemia compared to CKD patients by 2.7 points, respectively (likelihood ratio test p = 0.01). The APD group had also significantly greater stages 3 to 4 sleep compared to the CKD patients by 8.6 points (likelihood ratio test p = 0.009). In multivariate analyses and after adjustment for age, gender, race, and BMI, both APD and HD patients had higher average PSQI scores than CKD patients by 2.54 and 2.22 points, respectively (likelihood ratio test p = 0.005). No other comparisons of sleep parameters among groups reached statistical significance.

Limitations

The limitations of this study are the small sample size of the APD population and the demographic and clinical differences among the three study groups.

Conclusions

Despite differences in univariate analyses, after multivariate adjustment, APD patients had similar sleep parameters and sleep architecture and as poor SQ and symptoms of depression as HD patients. Future studies with larger APD cohorts are needed.

Executive summary of the KDIGO Controversies Conference on Supportive Care in Chronic Kidney Disease: developing a roadmap to improving quality care

Patients with advanced chronic kidney disease (CKD) have a high burden of physical and psychosocial symptoms, poor outcomes, and high costs of care. Current paradigms of care for this highly vulnerable population are variable, prognostic and assessment tools are limited, and quality of care, particularly regarding conservative and palliative care, is suboptimal. The KDIGO Controversies Conference on Supportive Care in CKD reviewed the current state of knowledge in order to define a roadmap to guide clinical and research activities focused on improving the outcomes of people living with advanced CKD, including those on dialysis. An international group of multidisciplinary experts in CKD, palliative care, methodology, economics, and education identified the key issues related to palliative care in this population. The conference led to a working plan to address outstanding issues in this arena, and this executive summary serves as an output to guide future work, including the development of globally applicable guidelines.

The influence of parathyroidectomy on restless legs syndrome in patients with renal hyperparathyroidism

BACKGROUND

Restless legs syndrome (RLS) is a common and poorly understood movement disorder that leads to unpleasant leg sensations. Although RLS can be idiopathic, secondary etiologies such as iron deficiency and renal failure are common. The aim of this prospective cohort study was to evaluate whether RLS is a common feature in patients undergoing parathyroidectomy for renal hyperparathyroidism (rHPT) and if RLS-related symptoms can be influenced by surgery.

METHODS

After providing written consent, patients who underwent a parathyroidectomy for rHPT between January and November 2011 answered a validated RLS-screening-questionnaire (RLSSQ). If this was suggestive for RLS a confirming questionnaire (IRLS) was also completed on the day before surgery, on the fifth postoperative day, and again during follow-up (minimum 12 months). Perioperative parathyroid hormone and calcium levels, as well as the scores of the questionnaires were analyzed.

RESULTS

Twenty-one patients (14 men, 7 women) with a mean age of 47.8 ± 3.2 years underwent total parathyroidectomy with bilateral cervical thymectomy and parathyroid autotransplantation for rHPT. The mean score of the RLSSQ of all 21 patients prior to operation was 6.1 ± 0.5. In 10 of 21 patients (47.6 %) the results of the RLSSQ were suggestive for RLS with a mean score of 8.0 ± 0.3. The consecutive scores of the IRLS in these latter patients significantly dropped from 26.6 ± 1.4 to 19.0 ± 2.2 between the preoperative and postoperative settings (p < 0.05). After a mean follow-up of 17.3 ± 3.7 months the mean scores of the RLSSQ and the IRLS were 6.1 ± 0.6 and 16.3 ± 1.8.

CONCLUSIONS

rHPT may play a major role in the severity of RLS-associated symptoms in patients with renal failure. Consequently, parathyroidectomy may prove to be a valuable tool to reduce RLS-associated morbidity in affected patients. However, larger prospective trials are required to confirm the possible relation between RLS and rHPT seen in the present study

Prevalence and sleep related disorders of restless leg syndrome in hemodialysis patients

Background:

Despite being frequently described, Restless Leg Syndrome (RLS) in patients, who are on hemodialysis, is a common disease which, has not been well documented in Iran.

Objectives:

The current study aimed to investigate the prevalence of RLS and its sleep disorders in Iranian patients on hemodialysis.

Patients and Methods:

In this multicenter cross sectional study, 397 consecutive patients on hemodialysis were evaluated by face-to-face interviews. RLS was diagnosed using the International RLS Study Group (IRLSS) criteria. In addition, three validated sleep disorder questionnaires (Insomnia Severity Index, Epworth sleepiness scale and Pittsburgh sleep quality index) were completed by the patients.

Results:

One hundred-twenty-six patients with RLS (31.7%; mean age 57.6 ± 15.4 years) participated in the current study. RLS mostly occurs in females (P < 0.001). RLS cases showed poorer quality of sleep (Pittsburgh Sleep Quality Index > 5, P = 0.001), higher scores of Epworth Sleepiness Scale (P < 0.001) and insomnia severity index (P = 0.001). Except thyroid gland dysfunction (P < 0.03, OR ≈ 2.50) and anti-hypertensive medications (P < 0.01, OR ≈ 1.7), there were no significant differences between age, duration of dialysis, etiology of renal insufficiency, intake of nicotine, alcohol or caffeine, and other associated comorbidities between the patients with and without RLS.

Conclusions:

In the current study, prevalence of RLS was near the weighted-mean prevalence of other studies (mean 30%, range 8%t-52%). This is not just racial variability and may attribute to narrow or wide definition of the disease, plus variations of the prevalence recording time, and sometimes not using the standard criteria or standard interview.

Nonapnea sleep disorders and incident chronic kidney disease: a population-based retrospective cohort study

Nonapnea sleep disorders (NASDs) are associated with an increased risk of stroke, diabetes, and hypertension. No longitudinal study has yet examined the association between NASD and chronic kidney disease (CKD) by using epidemiologic study methods. To test this hypothesis, we examined the effect of NASD on the incidence of CKD in a large population-based retrospective cohort study. Based on a retrospective cohort study of a general population sample of 128 to 436 patients in the Taiwan National Health Insurance Research Database from January 1, 1998 to December 31, 2001, 42 to 812 NASD patients were followed up for 10.2 ± 3.12 years, and additional 85 to 624 individuals had no NASD at baseline. The International Classification of Diseases, Ninth Revision, Clinical Modification was used to identify the diagnosis of disease. Cox proportional hazard regression models were used to assess the association between NASD and subsequent CKD risk. The incidence rate of CKD was significantly higher in the NASD cohort than in the comparison cohort (2.68 vs 1.88 per 1000 person-years, respectively). After we adjusted for age, sex, and comorbidities, the risk of developing CKD was significant for patients with NASD (adjusted hazard ratio [HR] = 1.13; 95% confidence interval [CI] = 1.05-1.22; P < 0.01). Among different types of NASDs, patients with sleep disturbance associated disorders had a 14% increased risk of developing CKD (95% CI = 1.03-1.26; P < 0.01), whereas patients with insomnia had a 13% increased risk of subsequent CKD (95% CI = 1.02-1.25; P < 0.05) compared with the non-NASD cohort. Kaplan-Meier survival analysis indicated that the CKD-free rate was 1% lower in the NASD cohort than in the comparison cohort (log-rank test, P < 0.0001). Our study provides evidence that patients with NASD have an increased risk of developing subsequent CKD compared with patients without NASD; men, elderly people, and patients with concomitant comorbidities are at the greatest risk.

Physical activity and self-reported symptoms of insomnia, restless legs syndrome, and depression: the comprehensive dialysis study

Symptoms of sleep and mood disturbances are common among patients on dialysis and are associated with significant decrements in survival and health-related quality of life. We used data from the Comprehensive Dialysis Study (CDS) to examine the association of self-reported physical activity with self-reported symptoms of insomnia, restless legs syndrome (RLS), and depression in patients new to dialysis. The CDS collected data on physical activity, functional status, and health-related quality of life from 1678 patients on either peritoneal (n = 169) or hemodialysis (n = 1509). The Human Activity Profile was used to measure self-reported physical activity. Symptoms were elicited in the following manner: insomnia using three questions designed to capture difficulty in initiating or maintaining sleep, RLS using three questions based on the National Institutes of Health workshop, and depression using the two-item Patient Health Questionnaire. We obtained data on symptoms of insomnia and depression for 1636, and on symptoms of RLS for 1622 (>98%) patients. Of these, 863 (53%) reported one of three insomnia symptoms as occurring at a persistent frequency. Symptoms of RLS and depression occurred in 477 (29%) and 451 (28%) of patients, respectively. The Adjusted Activity Score of the Human Activity Profile was inversely correlated with all three conditions in models adjusting for demographics, comorbid conditions, and laboratory variables. Sleep and mood disturbances were commonly reported in our large, diverse cohort of patients new to dialysis. Patients who reported lower levels of physical activity were more likely to report symptoms of insomnia, RLS, and depression.

Daytime sleepiness and quality of life in peritoneal dialysis patients

We aimed to compare automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD) therapy with regard to patients' excessive daytime sleepiness (EDS) and quality of life (QOL). EDS was assessed with the Epworth Sleepiness Scale (ESS) and QOL with the Medical Outcomes Study 36-Item Short Form (SF-36) health survey. We included 59 patients (CAPD/APD, 30/29; male/female, 33/26; age, 45.3±15.8 years; dialysis duration, 42.0±33.6 months). The CAPD and APD groups were similar with respect to factors that affected sleep quality (age, sex, duration of PD), smoking, alcohol intake, socioeconomic status, body mass index, comorbid disease, and various laboratory parameters. Although one patient (3.3%) treated with CAPD and four patients (13.8%) treated with APD experienced EDS, there was no significant differences in ESS scores between the CAPD and APD patients. There was no difference in the SF-36 total and subscale scores when APD patients were compared with CAPD patients. The independent predictors of ESS were the serum albumin level (β= -2.04, P<0.01), total SF-36 score (β= 0.08, P=0.02), social functioning score (β= -2.47, P=0.01), and role-emotional subscale score (β= -1.12, P=0.05). The incidence of EDS was slightly higher in APD patients, but it did not negatively affect daily activities or QOL.

Impact of sleep quality on cardiovascular outcomes in hemodialysis patients: results from the frequent hemodialysis network study

BACKGROUND

Poor sleep quality is a common, persistent, and important problem to patients with end-stage renal disease (ESRD). This report examines whether sleep quality is associated with dialysis treatment factors and other modifiable clinical factors in a large group of hemodialysis (HD) patients.

METHODS

Cross-sectional analyses were conducted on baseline data collected from participants in the Frequent Hemodialysis Network trials. Sleep quality was measured using the Medical Outcomes Study Sleep Problems Index II (SPI II), a 9-item measure of sleep quality with higher scores reflecting poorer sleep quality.

RESULTS

The participants had an age of 51.2 ± 13.6 years, 61% were male, 38% were black, and 42% had diabetes. Higher pre-dialysis serum phosphorus (per 0.5 mg/ml) (OR 0.91; 95% CI 0.85, 0.96) and depression (OR 0.16; 95% CI 0.10, 0.25) were independently associated with decrements in sleep quality. There was also a difference in time to recovery from dialysis for the fourth versus the first SPI II quartile (5.1 h; p < 0.0001).

CONCLUSION

These findings underscore the link between sleep and daytime function and suggest that improving sleep may provide an opportunity to improve outcomes in ESRD. Whether sleep problems may be improved by reduction of serum phosphorus or treatment of depression in the HD population merits further investigation.

Sleep apnea is a novel risk predictor of cardiovascular morbidity and death in patients receiving peritoneal dialysis

Sleep apnea syndrome is increasingly recognized in peritoneal dialysis patients; however, its prognostic implication in this population is unknown. To study this, we prospectively followed the clinical outcome of 93 peritoneal dialysis patients with baseline polysomnography. Of these, 51 were diagnosed with the syndrome defined by an apnea-hypopnea index (AHI) of at least 15 per hour. During a median follow-up of 41 months, there were 30 deaths, of which 17 were due to cardiovascular causes. Kaplan-Meier analysis for the entire follow-up period indicated that patients with sleep apnea at baseline had significantly higher all-cause and cardiovascular mortality during follow-up than those without. Minimal nocturnal saturation and desaturation indices were predictors of mortality and cardiovascular events at univariate analysis. Multivariable Cox regression analysis identified significant sleep apnea syndrome at baseline as an independent predictor of increased all-cause mortality independent of age, male gender, and diabetic status. Further, an absolute increase in the AHI was associated with an incremental risk of cardiovascular events. Thus, sleep apnea syndrome, detected at the start of peritoneal dialysis, is a novel risk predictor for subsequent mortality and cardiovascular events.

Sleep disorders and home dialysis

Sleep disorders, such as restless legs, periodic limb movements and sleep apnea, and sleep complaints such as insomnia and daytime sleepiness, are very common in end-stage renal disease patients despite treatment with 3-times-a-week conventional hemodialysis. If left untreated, they are likely to impair quality of life and may alter cardiovascular outcomes in this patient population. Home dialysis has the potential to improve sleep disorders by offering more effective dialysis than conventional modalities. Although there has been little direct comparison between the impact of home dialysis and conventional dialysis on sleep disorders, there is evidence that both nocturnal peritoneal dialysis and nocturnal hemodialysis improve sleep apnea. The impact of home dialysis on other sleep disorders and sleep complaints is less impressive, but the data, thus far, have been limited. Further research is required to evaluate the impact of home dialysis on all sleep disorders and sleep complaints in this patient population and to determine whether this improves quality of life and cardiovascular morbidity and mortality.

[Epidemiology of restless legs syndrome]

INTRODUCTION

Restless legs syndrome (RLS) is a chronic sensorimotor disorder where patients complain of an almost irresistible urge to move their legs. This urge can often be accompanied by pain or other unpleasant sensations, it either occurs or worsens with rest particularly at night, and improves with activity. The International Restless Legs Syndrome Study Group has established four essential criteria for clinical diagnosis of RLS.

STATE OF ART

Affecting an estimated 7.2 to 11.5% of the adult population, the symptoms of RLS may be associated with significant sleep disturbance and may have a negative impact on quality of life. The prevalence of RLS increases with age, and women are more frequently affected than men. In France, the estimated prevalence is 8.5%. Among sufferers, 4.4% complain of very severe symptoms. Although RLS is mainly idiopathic, several clinical conditions have been associated with it, especially iron deficiency with or without anemia, end-stage renal disease and pregnancy. These conditions may share a common pathophysiological mechanism involving a disorder of iron metabolism. By contrast, controversy persists as to whether polyneuropathy, particularly when associated with diabetes, is to be considered as an important cause of secondary RLS. This association is difficult to demonstrate as conventional electromyography is not adequate to detect small fiber neuropathy often associated with diabetes.

CONCLUSION AND PERSPECTIVES

RLS is often underdiagnosed and few subjects receive recommended RLS drug treatment. There is a clear need for complementary education to improve the accurate diagnosis of RLS. Indeed, better knowledge of this syndrome is a prerequisite to prompt an appropriate therapeutic management.

Restless legs syndrome in patients on hemodialysis: symptom severity and risk factors

Background and Purpose

Restless legs syndrome (RLS) is a sleep disorder that frequently occurs in dialysis patients, which disturbs the sleep and reduces the quality of life. The aim of this study was to determine the risk factors for RLS in dialysis patients.

Methods

Patients who visited any of four outpatient dialysis clinics between September 2005 and May 2006 were included in this study. The diagnosis of RLS and the severity assessment were made using the criteria described by the International Restless Legs Syndrome Study Group. We collected basic demographic data, clinical information, and laboratory findings, and then analyzed their association with various aspects of RLS using univariate and multivariate analyses.

Results

RLS was present in 46 (28.0%) of 164 dialysis patients. We found no significant risk factor for inducing RLS. The predialysis serum blood urea nitrogen (BUN) level in the dialysis patients with RLS was significantly correlated with RLS symptom severity.

Conclusions

Predialysis BUN is related to RLS symptom severity. Further studies on the underlying mechanism are needed.