Sleep behavior disorders in a large cohort of chinese (Taiwanese) patients maintained by long-term hemodialysis.

BACKGROUND: Disorders of sleep behavior and sleep-related breathing disorders are common in hemodialysis patients. Most such evidence is based on studies involving small numbers of patients. METHODS: We undertook a large multicenter analysis of sleep behavior in more than 700 Taiwanese patients on maintenance hemodialysis therapy for 6 months to 20-plus years by using self-administered questionnaires: the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and Berlin Questionnaire for risk for sleep apnea, validated for the general population. Patients also completed a questionnaire to assess symptoms related to restless legs and periodic limb movements (PLMs). Sleep behavior was analyzed in relation to demographic and dialysis-related parameters provided by the participating dialysis centers. RESULTS: Sleep disturbance was very common in this cohort, with problems of insomnia (66.6%) exceeding those related to daytime sleepiness (17.8%). Sleep disturbances were associated with restless legs syndrome (RLS)/PLM and a high risk for sleep apnea, determined by using the Berlin Questionnaire. Older age increased the odds of daytime sleepiness, but not insomnia. Lower dialysis dose (single-pool Kt/V) increased the likelihood of daytime sleepiness and was associated with greater rates for RLS/PLM and risk for sleep apnea. Use of antihypertensive medications (a probable surrogate for more severe hypertension) was associated strongly with high risk for sleep apnea. Smoking was associated with RLS/PLM and risk for sleep apnea, whereas consumption of stimulant beverages (coffee and tea) had contrary effects on RLS/PLM and risk for sleep apnea and were not implicated in measures of insomnia or daytime sleepiness. A greater likelihood of insomnia for greater hemoglobin levels and greater likelihood of daytime sleepiness for patients administered vitamin D analogues were not explained by the available data. CONCLUSION: Sleep disorders and sleep-related breathing disorders are common in hemodialysis patients. Greater attention in the care of dialysis patients needs to be directed to the diagnosis and management of sleep disorders.

Protecting the endothelium: a new focus for management of chronic kidney disease.

It is being increasingly recognized that cardiovascular disease (CVD) and its complications are the most important cause of morbidity and mortality in patients with chronic kidney disease (CKD) and dialysis patients. If outcomes for these patients are to be improved, therapeutic strategies at all stages of CKD will have to target the etiologies and mechanisms that lead to CVD. In this review, we focus on the central role of endothelial dysfunction as the critical precursor of CVD. We argue that a better understanding of endothelial dysfunction by nephrologists and dialysis physicians is necessary if there is to be success in limiting the CVD epidemic that kills and maims our patients. The extensive studies to explain the high prevalence of vascular disease in patients with CKD have shown the close relationship among endothelial dysfunction, inflammation, and atherosclerosis. The pathogenesis starts with endothelial cell injury from any of many possible causes, and strategies to reduce the burden of CVD in uremic and dialysis patients must be directed at restoring normal endothelial function or, at the least, preventing aggravation of endothelial damage. At the center of the exploration of endothelial dysfunction and atherosclerosis are oxidative stress and inflammation. Of these, which is the chicken and which is the egg is unknown, but in the setting of uremia, endothelial injury because of free radical, oxidative stress is likely to precede inflammation. The issues raised here are highly complex and most renal practitioners may not have been adequately exposed to the background research underlying current thinking of the pathogenesis of vascular disease. Clearly, progress in management of CVD in patients with CKD will require collaboration with experts in the research and treatment of vascular disease. Nephrologists seeking optimum outcomes for patients with CKD will need to become "endotheliologists" or, at the least, subscribe to a mission "to protect the endothelium."