The impact of OSA and CPAP treatment on cell adhesion molecules' night-morning variation.

PURPOSE: Obstructive sleep apnea (OSA) has been related to vascular inflammation and production of endothelial cell adhesion molecules (CAMs). We aimed to determine night-morning variation of CAMs in patients with OSA compared to controls and the effect of one-night continuous positive airway pressure (CPAP) treatment on them. METHODS: Nonsmoking men went through a full-attended polysomnography (PSG) study. Participants with moderate to severe OSA went through another PSG study while being treated with CPAP. Participants who did not have OSA composed the control group. Serum levels of intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and E-selectin were measured before and after sleep on both nights. RESULTS: Of 30 men, 20 had moderate to severe OSA while 10 did not. Night and morning ICAM-1 levels of patients with OSA were significantly higher than controls (p = 0.002 and p < 0.0001 respectively), while both night and morning VCAM-1 and E-selectin levels were not. Morning ICAM-1 levels of controls were significantly lower than night levels (p = 0.031), while morning ICAM-1, VCAM-1, and E-selectin levels of patients with OSA and morning VCAM-1 and E-selectin levels of controls were not. After CPAP treatment, the morning ICAM-1 levels, but not VCAM-1 levels, of patients with OSA were significantly lower than night levels (p = 0.006) and E-selectin levels showed a tendency for reduction (p = 0.06). CONCLUSIONS: OSA is associated with elevated night and morning ICAM-1 levels in adult men with OSA. Even one night of CPAP treatment restores the normal night-morning variation of ICAM-1 levels and may have an effect on E-selectin levels, as well.

Sleep apnea syndrome, inflammation and oxidative stress in hemodialysis patients.

INTRODUCTION: Sleep apnea syndrome (SAS) is an established cardiovascular risk factor in the general population related to inflammation and oxidative stress and is very common among hemodialysis patients. Cardiovascular disease and its complications is the main cause of death among hemodialysis patients. The aim of the present study was to investigate the role of SAS in the promotion of inflammation and oxidative stress and thus in the augmentation of cardiovascular risk in hemodialysis patients. METHODS: Thirty-seven hemodialysis patients underwent an overnight full polysomnography study. The following morning blood samples were obtained and TNF-α (tumor necrosis factor-α), IL-6 (interleukin-6), MPO (myeloperoxidase), and oxLDL (oxidized low density lipoprotein) were measured. FINDINGS: We investigated the correlation of patients' markers of inflammation and oxidative stress with their sleep parameters (total sleep time, AHI, apnea/hypopnea index; RDI, respiratory disturbance index; DI, desaturation index, mean and minimum SpO2 and percentage of sleep time with SpO2 < 90%). TNF-α correlated positively with BMI (r = 0.510, P < 0.0001) and total sleep time (r = 0.370, P = 0.027). IL-6 correlated positively with age (r = 0.363, P = 0.027), AHI (r = 0.385, P = 0.018), DI (r = 0.336, P = 0.042) and percentage of sleep time with SpO2 < 90% (r = 0.415, P = 0.012) and negatively with mean SpO2 (r = -0.364, P = 0.027). Myeloperoxidase correlated positively with AHI (r = 0.385, P = 0.018), DI (r = 0.380, P = 0.02) and percentage of sleep time with SpO2 < 90% (r = 0.388, P = 0.019). Finally, oxLDL correlated positively with BMI (r = 0.443, P = 0.007), AHI (r = 0.395, P = 0.015), RDI (r = 0.328, P = 0.048) and total sleep time with SpO2 <90% (r = 0.389, P = 0.019). CONCLUSIONS: These results indicate that, in hemodialysis patients, the severity of SAS and nocturnal hypoxia correlated positively with markers of inflammation and oxidative stress.

Peritoneal dialysis-related infections recommendations: 2016 update. What is new?

In 2016, the International Society of Peritoneal Dialysis (ISPD) published guidelines that focus on the importance of both prevention and treatment of peritonitis. For once more, the need for annual reporting of peritonitis rates and recording of peritonitis and exit-site infections, isolated microorganism and antimicrobial susceptibilities as a central component of a quality improvement program is highlighted. Data on new antibiotic regimens, techniques for microorganism isolation and peritoneal dialysis solutions are included. Training of both peritoneal dialysis nurses and patients seems to be crucial, while the modifiable risk factors for peritonitis seem to be of great interest. In this article, we record the changes in the last ISPD (2016) guidelines compared to the previous ones published in 2010.

Twenty-four-hour intraocular pressure monitoring in normotensive patients undergoing chronic hemodialysis.

PURPOSE: To investigate 24-hour intraocular pressure (IOP) changes caused by hemodialysis (HD). METHODS: A prospective, observational, comparative 24-hour trial was performed on consecutive subjects with normal IOP undergoing maintenance HD 3 days a week between 13:00 and 17:00 hours in an academic setting. Following a comprehensive ocular assessment, those with conditions that may influence IOP were excluded and one eye was randomly selected. Twenty-four-hour IOP monitoring was performed on HD day 1 and then on a day without HD. The IOP was measured at 10:00, 13:00, 15:00, 17:00, 22:00, 02:00, and 06:00 employing Goldmann and Perkins tonometry on habitual position. During the course of 1 year, 18 patients completed the study. RESULTS: Monitoring of IOP on HD day showed a significantly higher mean 24-hour IOP (15.4 ± 2.7 vs 14.1 ± 2.2 mm Hg; p = 0.025), higher mean peak 24-hour IOP (18.5 ± 3.5 vs 15.8 ± 2.5 mm Hg; p = 0.003), and wider 24-hour IOP fluctuation (6.2 ± 2.3 vs 4.0 ± 1.9 mm Hg; p = 0.001). When individual time points were compared, IOP was significantly higher at 17:00 on HD day, reflecting a gradual IOP elevation during HD (p = 0.021). Further, during the HD procedure (13:00-17:00), the mean IOP was significantly higher on a HD day (16.4 ± 3.0 vs 14.7 ± 2.4 mm Hg; p = 0.004). CONCLUSIONS: This prospective, before/after trial suggests that HD significantly impacts 24-hour IOP characteristics in normotensive eyes. The long-term significance of these findings requires further elucidation in normotensive patients and, predominantly, in patients with glaucoma undergoing HD.

Animal models in peritoneal dialysis.

Peritoneal dialysis (PD) has been extensively used over the past years as a method of kidney replacement therapy for patients with end stage renal disease (ESRD). In an attempt to better understand the properties of the peritoneal membrane and the mechanisms involved in major complications associated with PD, such as inflammation, peritonitis and peritoneal injury, both in vivo and ex vivo animal models have been used. The aim of the present review is to briefly describe the animal models that have been used, and comment on the main problems encountered while working with these models. Moreover, the differences characterizing these animal models, as well as, the differences with humans are highlighted. Finally, it is suggested that the use of standardized protocols is a necessity in order to take full advantage of animal models, extrapolate their results in humans, overcome the problems related to PD and help promote its use.

Peritoneal dialysis-related infections recommendations: 2010 update. What is new?

The International Society of Peritoneal Dialysis (ISPD) 2010 guidelines on PD-related infections reflect the bulk of knowledge acquired over the last 5 years. It includes new information about causative agents of peritonitis, isolation techniques, or therapeutic regimens. Monitoring of infection rates by reporting of peritonitis and exit site infections, isolated microorganism, and presumed etiology is recommended. Furthermore, special focus is given on careful evaluation of each episode of peritonitis in order to determine the route of infection and to reassess patient's training. In this article, we record the changes in the last ISPD (2010) guidelines compared to the previous ones published in March 2005.