Endogenous soluble receptor of advanced glycation end-products (esRAGE) is negatively associated with vascular calcification in non-diabetic hemodialysis patients

Background

Advanced glycation end-products (AGE) accumulate in CKD and may predispose to cardiovascular disease by inducing inflammatory and oxidant stress in the vascular endothelium. Soluble forms of the receptor for AGE (RAGE) may be protective against these effects by binding AGE in the soluble phase. Accumulating evidence suggests a protective role of soluble RAGE against vascular calcification. This study investigates the association between endogenous soluble RAGE (esRAGE) and vascular calcification in hemodialysis patients.

Methods

We studied 65 non-diabetic hemodialysis patients, on 3?×?4?h dialysis schedule, and 19 controls. Serum levels of esRAGE, hsCRP, parathormone, lipids, calcium, and phosphorus were measured. Aortic calcification index (ACI) was measured using non-contrast CT of the abdominal aorta.

Results

Aortic calcification was detected in 64 out of 65 hemodialysis patients. Levels of esRAGE were lower in hemodialysis patients (278?pg/ml, SD 101.1) than in controls (443?±?109?pg/ml; P?=?0.001). ACI correlated negatively in stepwise multivariate analysis with esRAGE (P?=?0.002) and positively with hsCRP (<0.0001), systolic blood pressure (P?<?0.0001) and dialysis vintage (P?=?0.05); R ²?=?0.65.

Conclusion

Levels of esRAGE were low among hemodialysis patients and correlated negatively with ACI.     

QT dispersion predicts mortality and correlates with both coronary artery calcification and atherosclerosis in hemodialysis patients

Purpose

QT dispersion (QTd) was shown to be an independent predictor of mortality in hemodialysis (HD) patients. It may be hypothesized that coronary artery calcification is related to QTd in HD patients because widespread calcification may also involve the cardiac conducting system in these patients. In this study, we aimed to investigate the relationships of corrected QTd (QTcd) with coronary artery calcification score (CACS), carotid plaque score (CPS) and possible influence of these parameters on survival of HD patients.

Methods

Seventy-two HD patients (33 male, 39 female) were enrolled into the study. Mean age of the patients was 44 ± 12 years. Mean follow-up duration was 77 ± 24 months. CACS was determined by computed tomography. QTcd values were calculated as the difference of maximum and minimum QT intervals. Left ventricular mass index (LVMI) and CPS were measured by echocardiography.

Results

QTcd was significantly correlated with CACS (r = 0.233, p = 0.049), CPS (r = 0.354, p = 0.003) and LVMI (p = 0.011, r = 0.299). CPS was found to be significantly higher in the group with high QTcd (>60 ms) [2 (1–4) versus 0 (0–1), p = 0.02]. CACS was significantly correlated with age (r = 0.44, p < 0.001), LVMI (r = 0.52, p < 0.001) and CPS (r = 0.32, p = 0.003). In Kaplan–Meier analysis, survival of patients with high QTcd was significantly lower than the patients with low QTcd. In Cox regression analysis for predicting mortality, age, serum albumin and QTcd were found to be the independent predictors of mortality.

Conclusions

QTcd independently predicted mortality, and it was significantly associated with coronary artery calcification, left ventricular hypertrophy and atherosclerosis in HD patients.     

Calcification of the thoracic aorta determined by three-dimensional computed tomography predicts cardiovascular complications in patients undergoing hemodialysis

Purpose

In patients on dialysis, the most common cause of death is cardiovascular disease. This is caused, at least in part, by excessive vascular calcification. Studies that have examined coronary calcification have been published, but these measurements require expensive equipment. Here, we used computed tomography to determine aortic calcification and evaluated these data as prognostic markers for cardiovascular disease.

Methods

Computed tomography with contrast medium was performed on 49 patients undergoing hemodialysis (29 males and 20 females; average age, 68.9 ± 11.0 years). A calcification score (CS) was defined as the ratio of the volume of vascular calcification to the volume of the thoracic aorta. All patients were monitored for cardiovascular end points, which included cerebral infarction or hemorrhage, myocardial infarction, electrocardiographic, or echocardiographic abnormalities that suggested myocardial ischemia, cardiac surgery, leg amputation, and hospitalization or death due to heart failure.

Results

Patients were followed for 3 years, with 12 patients reaching the end point. Both high CS (p = 0.007) and male gender (p = 0.009) were significantly associated with cardiovascular events. In contrast, events were not related to age, dialysis duration, diabetes mellitus, smoking status, low-density lipoprotein cholesterol level, pulse-wave velocity, maximum intima-media thickness of the carotid artery wall, systolic blood pressure, or left ventricular hypertrophy. Multiple logistic regression analysis revealed that a high baseline CS was a significant predictor for cardiovascular events (p < 0.05).

Conclusions

Calcification of the thoracic aorta determined by three-dimensional computed tomography predicts cardiovascular complications in patients on hemodialysis.     

Barriers to medication adherence and its relationship with outcomes in pediatric dialysis patients

Background

Medication adherence is a major factor determining outcome in children with chronic disease. Children with end-stage renal disease are challenged with requirements for renal replacement therapy in addition to complicated medication regimens.

Methods

We assessed barriers to medication adherence in 22 pediatric patients receiving chronic dialysis [63.6 % hemodialysis (HD), 36.4 % peritoneal dialysis (PD); age 15.9?±?0.7 years, dialysis vintage 31.6?±?6.5 months]. Adherence was assessed by a 16-question survey with a maximum score (difficulty) of 64.

Results

The overall mean adherence score was 30.9?±?2.4 (range 16–49; median? 27.5). There was a trend for lower adherence scores in patients on HD (27.5?±?2.9) compared to those on PD (36.8?±?3.7) (p?=?0.06). Compared to HD patients, the mean score/question was significantly higher in PD patients (1.7?±?0.2 vs. 2.4?±?0.2, respectively; p?=?0.006). Of the 16 questions, HD and PD patients gave a mean response of ≤1.2 for five and zero questions, respectively. Neither gender, age nor dialysis vintage was related to adherence scores. There was also a trend for adherence scores to be higher in females (35.6?±?3.7) than in males (27.5?±?2.9) (p?=?0.1), but this difference did not reach statistical significance. Markers of mineral bone disease were similar in HD and PD patients. Among all targets in HD and PD patients combined, there was no relationship between adherence scores and number of targets reached (r?=??0.09, p?=?0.7).

Conclusion

There are many barriers to medication adherence in pediatric patients receiving dialysis. In our patient group the difficulties were more evident in patients receiving PD than in those receiving HD.     

Prevalence of intracranial artery calcification in hemodialysis patients—a case–control study

Background

Intracranial artery calcification has been reported to be an independent risk factor for ischemic stroke. Also, existence of a positive correlation has been reported between the presence of arterial calcification and that of ischemic changes in the area supplied by such arteries. While intracranial artery calcification has frequently been observed on computed tomographic (CT) images of the brain in hemodialysis patients, its prevalence has not been reported previously. We investigated our hemodialysis outpatients to determine the prevalence of intracranial artery calcification in these patients in comparison with that in healthy controls.

Methods

Brain CT examinations were performed in 107 patients under maintenance hemodialysis therapy. For comparison, 43 representatives of the general population who underwent a brain CT examination as part of a health checkup were also studied as control subjects.

Results

Intracranial calcifications were more frequently found among hemodialysis patients (87.9%) than among control subjects (53.5%, P?=?0.0003), and the prevalences of calcification in each of the intracranial arteries in the two groups were as follows: vertebral artery (65.5% vs. 25.6%, P?=?0.0002), internal carotid artery (62.1% vs. 18.6%, P?<?0.0001), basilar artery (34.5% vs. 34.9%, ns), anterior cerebral artery (0 vs. 2.3%, ns), middle cerebral artery (24.1% vs. 20.9%, ns), and posterior cerebral artery (5.2% vs. 4.7%, ns).

Conclusions

A much higher rate of intracranial artery calcification was observed in hemodialysis patients than in the general population, and the most frequently involved sites of calcification in these patients were the relatively large intracranial arteries.     

Hyperlipidemia, oxidative stress, and intima media thickness in children with chronic kidney disease

Background

The roles of dyslipidemia and oxidative stress in the early phases of atherosclerosis were tested in children with chronic kidney disease (CKD). Intima media thickness of common carotid arteries (cIMT) is used as a measure of early atherosclerosis.

Methods

Fifty-two pediatric CKD patients were enrolled in the study (10 with chronic renal failure [CRF], 22 with a renal transplant [RT], 20 with chronic hemodialysis (cHD) patients, and 36 healthy children (control group, CG). Lipid status, oxidative stress, and paraoxonase 1 (PON1) status were assessed. cIMT was measured by ultrasound, adjusted for age and sex, and presented as standard deviation scores (SDS).

Results

Children with CKD had disturbed lipid content, which was most pronounced in cHD children, with higher free cholesterol and triglycerides compared with healthy children. Oxidative stress was markedly increased (malodialdehyde [MDA, μmol/L]: CRF 1.50?±?0.26, RT 1.55?±?0.40, cHD 1.77?±?0.34, CG 0.97?±?0.33, p?<?0.001) and antioxidative defense was compromised (superoxide dismutase [SOD, U/L]: CG 120?±?21, CRF 84?±?25, RT 93?±?12, cHD 119?±?37, p?<?0.001). Multiple linear regression analysis showed that a model that included disease duration, blood pressure, urea, lipid, and oxidative status parameters accounted for more than 90% of the variability of cIMT-SDS.

Conclusions

Early atherosclerosis in CKD children is caused, at least in part, by dyslipidemia and oxidative stress. Monitoring of vessel wall changes, along with assessment of oxidative stress status and high density lipoprotein (HDL) functionality is necessary to ensure better therapeutic strategies for delaying atherosclerotic changes in their asymptomatic phase.     

Effects of Gastric Band Adjustments on Intraluminal Pressure

Background

Understanding of the effects of adjustments to laparoscopic adjustable gastric band (LAGB) volume is limited. Changes in intraluminal pressure may be important and explain patients reporting a tighter LAGB after saline is removed and an identical volume replaced.

Methods

Using high-resolution manometry, changes in the basal intraluminal pressure at the level of the LAGB in response to sequential, small alterations in LAGB volume were recorded. All fluid was removed from the LAGB and replaced, pressures and motility were reassessed.

Results

Sixteen patients (four males, age 45.4?±?13.2 years) participated. A linear increase (r ²?=?0.87?±?0.12) in intraluminal pressure was observed after a threshold volume was reached. The threshold volume varied considerably (1.0 to 5.8 ml). The gradient of the linear increase was 21.2?±?8.7 mmHg/ml. The mean basal intraluminal pressure at the level of the LAGB was initially 19.1?±?8.9 mmHg and increased to 37.0?±?20.4 mmHg (p?=?0.001) after removing and replacing the same volume of saline. There was an increase in distal esophageal peristaltic pressure (123.5?±?34.7 vs. 157.4?±?52.6 mmHg, p?=?0.003) and a decrease in the proportion of normal swallows (0.85?±?0.22 vs. 0.53?±?0.47, p?=?0.02). Nine patients also developed adverse symptoms.

Conclusions

Intraluminal pressure at the level of the LAGB is an objective measure of the restriction produced by LAGBs. The addition of fluid to the LAGB results in a linear increase in intraluminal pressure once a threshold volume is reached. The removal and replacement of the same volume of saline from the LAGB may temporarily increase intraluminal pressure.     

Intima media thickness in children undergoing dialysis

Background

Uremic vasculopathy, including vascular calcification, increases the risk for cardiovascular disease and mortality in chronic kidney disease (CKD) patients. We have investigated the prevalence and factors associated with vasculopathy in children undergoing peritoneal dialysis (PD) or hemodialysis (HD) in a single center.

Methods

Common carotid intima media thickness (cIMT) and its relation with demographics, biochemical parameters and medication was analyzed in 60 patients (mean age 12.9?±?3.4?years; 27 girls) treated with PD (n?=?31) or HD (n?=?29) for 34?±?34?months. Patients were divided into two groups: normal cIMT and increased cIMT.

Results

Mean levels of calcium, phosphate and calcium/phosphate product were in the normal range, the but parathyroid hormone level, 729?±?670?pg/mL, was higher than the National Kidney Foundation Kidney Disease Outcome Quality Iniative (K/DOQI) recommendations. Twenty-nine patients had increased cIMT, which was associated with time on dialysis of?>2?years, hypercalcemia, higher daily dose of calcitriol and HD (vs. PD). In the multivariate analysis, accounting for time on dialysis, HD persisted as a risk for increased cIMT.

Conclusions

The prevalence of increased cIMT in children on dialysis is similar to that reported in adults with CKD and increased with time on dialysis. HD was associated with increased cIMT, independently of time on dialysis; however, the results should be interpreted with caution due to the possible impact of confounding factors. These results underline the need to monitor and, if possible, prevent and treat increased cIMT in children on dialysis.     

Whole-body single-frequency bioimpedance analysis in pediatric hemodialysis patients

Background

We hypothesized that the percent change in resistance (%RΔ) from bioimpedance analysis (BIA) measurements during hemodialysis (HD) can provide information on pediatric HD patients’ hydration status.

Methods

Whole-body single-frequency BIA measurements were obtained before HD, each hour on HD, and after HD during two HD sessions. Pre-and post-HD weights, blood pressures, Crit-Line® measurements, and intradialytic symptoms were collected on the day of the BIA measurements.

Results

One hundred and thirty BIA measurements were obtained from 14 HD patients. The group was 43 % girls, and the mean age was 13.2?±?4.4 years. Percent change in resistance was 13.5?±?10.8 % at the end of HD; %RΔ correlated with percent body weight change (%BWΔ) following HD (r?=??0.83, P?<?0.01), as well as with percent blood volume change (%BVΔ) (r?=??0.79, P?<?0.01). The %RΔ was similar between patients with and without hypertension immediately before HD and was greater in those with intradialytic symptoms (19.1?±?7.7 %) than in those without (9.9?±?11.2 %) (P?=?0.02). Patients with left ventricular hypertrophy (LVH) had lower %RΔ (7.2?±?9.7 %) than those without (19.5?±?7.7 %) (P?=?0.03). Left ventricular mass index (LVMI) also correlated strongly with %RΔ (r?=??0.79, P?=?0.004) and %BWΔ (r?=?0.82, P?=?0.002).

Conclusions

Our study showed that %RΔ strongly correlates with %BWΔ and %BVΔ and that %RΔ also correlated with intradialytic symptoms and LVMI.     

Persistently low intact parathyroid hormone levels predict a progression of aortic arch calcification in incident hemodialysis patients

Background

Recent observational studies have found that low intact parathyroid hormone (iPTH) is related with mortality in hemodialysis patients and these findings may be considered to be the result of accelerated cardiovascular calcifications in adynamic bone disease. This study was aimed to determine the relationship between persistently low iPTH and aortic arch calcification (AAC) in incident hemodialysis patients.

Methods

From January 2004 to December 2008, a total of 94 incident hemodialysis patients were enrolled in this study. They were divided into three groups according to the changing patterns of iPTH during the first year of hemodialysis. ACC was scored on posterior–anterior plain chest X-rays using a specific scale at the initiation of dialysis and followed till May 2011.

Results

The median follow-up periods were 46.9?months. The prevalence of baseline AAC and its progression were the highest in the persistently low iPTH group. Also, all-cause mortality was the highest in this group. Age, baseline calcification score and persistently low iPTH independently contributed to the progression of calcification by multivariate logistic regression analyses (HR 1.083, 95% CI 1.023–1.147, P?=?0.006; HR 3.320, 95% CI 1.023–10.789, P?=?0.046; HR 5.207, 95% CI 1.027–26.412, P?=?0.046, respectively). Also, mortality was relatively higher in calcification progressor compared to non-progressor (39.3, 18.2%, P?=?0.030).

Conclusion

Persistently low iPTH was an independent risk factor for both AAC and mortality in incident hemodialysis patients.     

Investigation of anal sphincter function following Mainz pouch type II urinary diversion after radical cystectomy

Purposes

Our aim was to evaluate the anal sphincter function following cystectomy with urinary diversion of Mainz pouch II.

Methods

Seventy-six patients were involved in our survey, and the cohort was for two groups divided. The first group was a retrospective review of 40 patients with examination of the state of continence. Comparative examinations on anal sphincter function and the quality of life survey were carried out. The second group consisting of 15 patients underwent a prospective investigation including rectal manometry in both the pre- and postoperative periods. Measurements of resting anal sphincter pressure (RASP), maximal anal closing pressure (MACP) and the function of the recto anal inhibitions reflex were taken.

Results

In the first part of our investigation, 80% of the patients were considered as continent. There were no significant differences observed between RASP values in the cases of continent as well as of incontinent patients (79.2?±?2 vs. 73.6?±?68.4?mmHg, p?=?0?C53); however, the MACP values of the continent patients were significantly higher (204.3?±?22.8 vs. 117.3?±?14?mmHg, p?=?0.001). In the course of the second experiment, both the RASP (86.3?±?18.7 vs. 76.1?±?13.9?mmHg p?=?0.0049) and the MACP (232.2?±?53.8 vs. 194.1?±?74.5?mmHg, p?=?0.0054) were detected as decreasing in the case of the incontinent group.

Conclusions

A decrease in rectal sphincter function is responsible for incontinence following Mainz pouch type II diversion, and this dysfunction can be correlated with the surgery. Ureterosigmoideostomy is therefore considered as a useful method of urinary diversion only in selected cases with proven good sphincter function.     

Randomized trial of bioelectrical impedance analysis versus clinical criteria for guiding ultrafiltration in hemodialysis patients: effects on blood pressure, hydration status, and arterial stiffness

Background

Chronic fluid overload is common in maintenance hemodialysis (HD) patients and is associated with severe cardiovascular complications, such as arterial hypertension, left ventricular hypertrophy, congestive heart failure, and arrhythmia. Therefore, a crucial target of HD is to achieve the so-called dry weight; however, the best way to assess fluid status and dry weight is still unclear. Dry weight is currently determined in most dialysis units on a clinical basis, and it is commonly defined as the lowest body weight a patient can tolerate without developing intra-dialytic or inter-dialytic hypotension or other symptoms of dehydration. One of the most promising methods that have emerged in recent years is bioelectrical impedance analysis (BIA), which estimates body composition, including hydration status, by measuring the body??s resistance and reactance to electrical current. Our objective was to study the effect BIA-guided versus clinical-guided ultrafiltration on various cardiovascular disease risk factors and markers in HD patients.

Materials and methods

We included 135 HD patients from a single center in a prospective study, aiming to compare the long-term (12?months) effect of BIA-based versus clinical-based assessment of dry weight on blood pressure (BP), pulse wave velocity (PWV), and serum N-terminal fragment of B-type natriuretic peptide (NT-proBNP). The body composition was measured using the portable whole-body multifrequency BIA device, Body Composition Monitor??BCM^? (Fresenius Medical Care, Bad Homburg, Germany).

Results

In the ??clinical?? group there were no changes in BP, body mass index (BMI), and body fluids. The PWV increased from 7.9?±?2.5 to 9.2?±?3.6?m/s (P?=?0.002), whereas serum NT-proBNP decreased from 5,238 to 3,883?pg/ml (P?=?0.05). In the ??BIA?? group, BMI and body volumes also did not change; however, there was a significant decrease in both systolic BP, from 144.6?±?14.7 to 135.3?±?17.8?mmHg (P?P?P?=?0.001) and NT-proBNP decreased from 7,552 to 4,561?pg/ml (P?=?0.001).

Conclusion

BIA is not inferior and possibly even better than clinical criteria for assessing dry weight and guiding ultrafiltration in HD patients.     

Semiquantitative analysis of indocyanine green videoangiography for cortical perfusion assessment in superficial temporal artery to middle cerebral artery anastomosis

Background

Postoperative hyperperfusion may lead to severe neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. However, there are no reliable modalities to predict the occurrence of postoperative hyperperfusion during surgery. The purpose of this study is to evaluate whether a semiquantitative analysis of indocyanine green (ICG) videoangiography could be useful in predicting postoperative hyperperfusion after STA-MCA anastomosis.

Methods

This study included seven patients who underwent STA-MCA anastomosis due to occlusive carotid artery diseases. During surgery, ICG videoangiography was performed before and after bypass procedures, and ICG intensity–time curves were semiquantitatively analyzed to evaluate hemodynamic changes by calculating maximum intensity, time to peak (TTP), and blood flow index (BFI).

Results

Maximum intensity significantly increased from 252.6?±?132.5 to 351.7?±?151.9 after bypass (p?<?0.001). TTP was significantly shortened from 12.9?±?4.4 s to 9.8?±?3.7 s (p?<?0.001). Furthermore, BFI significantly increased from 33.9?±?28.1 to 74.6?±?88.4 (p?<?0.05). Postoperative hyperperfusion was observed in five of seven patients 1 day after surgery. The ratio of BFI before and after bypass procedures was significantly higher in patients with postoperative hyperperfusion than those without, 2.5?±?1.1 and 1.5?±?0.4, respectively (p?=?0.013).

Conclusions

These findings suggest that semiquantitative analysis of ICG videoangiography is helpful in predicting occurrence of hyperperfusion after STA-MCA anastomosis in patients with occlusive carotid artery diseases.     

Home systolic blood pressure on the morning of dialysis days has prognostic impact for hypertensive hemodialysis patients

Background

Hypertension is a leading cause of cardiovascular (CV) disease in the general population. Although hypertension is very common in maintenance hemodialysis (HD) patients, adequate blood pressure (BP) values and measurement timing have not been defined.

Methods

A total of 49 hypertensive HD patients were recruited. Average age was 63?±?11?years, and duration of dialysis therapy was 6.2?±?4.2?years. Dialysis unit BPs and various types of home BPs were separately measured, and which BPs were the most critical markers in evaluating the effect of hypertension on left ventricular hypertrophy and CV events was investigated.

Results

Predialysis systolic BPs were not correlated with any home BPs. Left ventricular mass index (LVMI) had a significant positive correlation with home BPs, especially morning systolic BPs on HD days (P?P?Conclusions Home BP, especially systolic BPs in the morning on HD days, can provide pivotal information for management of HD patients.     

Dental calculus formation in children and adolescents undergoing hemodialysis

Background

This study aimed to determine whether dental calculus formation is really higher among patients with chronic kidney disease undergoing hemodialysis than among controls. Furthermore, the study evaluated correlations between dental calculus formation and dental plaque, variables that are related to renal disease and/or saliva composition.

Methods

The Renal Group was composed of 30 patients undergoing hemodialysis, whereas the Healthy Group had 30 clinically healthy patients. Stimulated whole saliva and parotid saliva were collected. Salivary flow rate and calcium and phosphate concentrations were determined. In the Renal Group the saliva collection was carried out before and after a hemodialysis session. Patients from both groups received intraoral exams, oral hygiene instructions, and dental scaling. Three months later, the dental calculus was measured by the Volpe–Manhold method to determine the rate of dental calculus formation.

Results

The Renal Group presented a higher rate of dental calculus formation (p?r?=?0.44, p?p?Conclusion In conclusion, patients undergoing hemodialysis presented accelerated dental calculus formation, probably due to salivary variables.     

Association between high-molecular-weight adiponectin and bone mineral density in hemodialysis patients

Background

Chronic kidney disease-mineral and bone disorder is a regular complication seen in hemodialysis patients and leads to substantial increases in the fracture rate, morbidity, and mortality. Discovered a few years ago, several clinical studies have shown a negative correlation between adiponectin and bone mineral density (BMD) independently of confounding factors. The relationship between adiponectin and bone metabolism in hemodialysis patients has not been fully described yet. We conducted this study to investigate the relationship between serum adiponectin concentration and the BMD in hemodialysis patients.

Methods

We enrolled 92 hemodialysis patients who were receiving maintenance hemodialysis therapy at Towa Hospital. A peripheral blood sample was obtained, and standard biological data and the serum high-molecular-weight (HMW) adiponectin level were measured. BMD was assessed using dual-energy X-ray absorptiometry scans.

Results

In male hemodialysis patients, BMD was negatively related to age (r = ?0.299, P = 0.012), duration of hemodialysis therapy (r = ?0.31, P = 0.009), and log [HMW-adiponectin] (r = ?0.31, P = 0.009) and positively related to body weight (r = 0.332, P = 0.004) and BMI (r = 0.297, P = 0.013). In female hemodialysis patients, BMD was negatively related to age (r = ?0.499, P = 0.018) and log [HMW-adiponectin] (r = ?0.46, P = 0.030) and positively related to triglyceride (r = 0.491, P = 0.020).

Effects of lowering dialysate sodium on carotid artery atherosclerosis and endothelial dysfunction in maintenance hemodialysis patients

Purpose

Our aim in this study was to examine the effects of low-sodium dialysate on carotid artery atherosclerosis, endothelial dysfunction, and blood pressure (BP) in maintenance hemodialysis (HD) patients.

Methods

After baseline measurements were obtained, the dialysate sodium concentration was reduced from 140 to 137?mEq/L. Carotid artery intima-media thickness (CIMT) and flow-mediated dilatation (FMD %) were measured before and after 6?months of HD with low-sodium dialysate. Interdialytic weight gain (IDWG), pre- and post-dialysis BP, and dialysis-related symptoms were monitored during the study.

Results

Fifty-two patients were enrolled, and 41 patients completed the study. Twenty-one patients had hypertension and were receiving antihypertensive medications. The average number of antihypertensive drugs per patient was 1.9?±?0.8. There was no significant reduction in BP at the end of the study, but the average number of antihypertensive drugs was reduced to 1.2?±?0.4 (P?<?0.001). There were significant improvements in CIMT (P?=?0.003) and FMD (P?<?0.001) with low-sodium HD. The IDWG decreased significantly during the low-sodium dialysate treatment (P?<?0.001). However, hypotensive episodes and cramps were more frequent during the study period.

Conclusions

Our study demonstrated that the lowering of dialysate sodium concentration reduced CIMT, improved FMD, and provided better control of IDWG and BP, but increased the incidence of dialysis-related symptoms.     

The role of sympathectomy on the regulation of basilar artery volume changes in stenoocclusive carotid artery modeling after bilateral common carotid artery ligation: an animal model

Background

Stenoocclusive carotid artery disease causes important histomorphologic changes in all craniocervical vasculatures, such as luminal enlargement, vascular wall thinning, elongation, convolutions, and aneurysm formation in the posterior circulation. Although increased pressure, retrograde blood flow, and biochemical factors are described in the pathogenesis of vascular remodelisation, the vasoregulatory role of the autonomic nervous system has not been investigated thus far. We investigated the relationship between the sympathetic nervous system and the severity of histomorphologic alterations of basilar arteries after bilateral common carotid artery ligation (BCCAL).

Material and methods

This study was conducted on 21 rabbits. The rabbits were randomly divided into three groups: baseline group (n?=?5), sympathectomy non-applied group (SHAM; n?=?8), and sympathectomy applied group (n?=?8) before bilateral common carotid artery ligation. Permanent ligation of the prebifurcations of the common carotid arteries was performed to replicate stenoocclusive caroid artery disease. Basilar artery volumes were measured after ligation. Volumes of the basilar arteries were estimated by stereologic methods and compared between groups.

Results

Luminal enlargement, wall thinning, elongation, convolutions, and doligoectatic configurations were detected in the majority of basilar arteries. The mean basilar arterial volume was 4.27?±?0.22 mm3 in the baseline group; 5.28?±?0.67 mm³ in the SHAM group, and 8.84?±?0.78 mm3 in the study group. The severity of basilar enlargement was significantly higher in the study group compared with the SHAM (p?<?0.005) and baseline groups (p?<?0.001).

Conclusions

Sympathectomy causes basilar artery enlargment, which is beneficial for maintaining cerebral blood flow; however, it also causes wall thinning, elongation, convolution, and aneurysm formation, which may be hazardous in stenoocclusive carotid artery disease. Sympathectomy can prevent new vessel formation and hyperthyrophic changes at the posterior circulation. Neovascularisation is not detected adequately in sympathectomised animals.     

Is residual renal function and better phosphate control in peritoneal dialysis an answer for the lower prevalence of valve calcification compared to hemodialysis patients?

Introduction

Cardiac valve calcification (CVC) has long been regarded as a consequence of abnormal calcium–phosphate metabolism in uremic patient associated with increased cardiovascular mortality in this population. We evaluated the association between residual renal function (RRF), phosphate level and valve calcification in peritoneal dialysis (PD) and hemodialysis (HD) patients.

Methods

We studied 30 stable PD patients (60 % males; mean age 57 ± 12.36 years) and 34 HD patients (58.8 % males; mean age 50.8 ± 10.4 years) on renal replacement therapy (RRT) from 6 up to 36 months. The presence of CVC was assessed by standard bi-dimensional echocardiography. RRF was calculated by standard technique.

Results

Valve calcification was more frequently found in HD compared to PD patients (70.6 vs 29.4 %, p = 0.007). Significantly lower phosphate [1.38 ± 0.41 versus 1.99 ± 0.35 mmol/L (p < 0.0001)], a higher RRF [4.09 ± 2.09 ml/min vs 0.62 ± 0.89 ml/min (p < 0.0001)], and older age [57 ± 12.36 years vs 50.8 ± 10.4 years (p = 0.033)] were observed in PD as compared to HD patients. The logistic regression analysis for the presence of valve calcification when adjusted for age and diabetes, with type of therapy, serum phosphate, RRF, CRP, and serum albumin as variables in the model, revealed significant association between the presence of valve calcification and age and RRF. The correlation between phosphate levels and RRF was even stronger in PD patients than in HD patients (r = ?0.704; p = 0.0001) vs (r = ?0.502; p = 0.02).

Conclusions

Our study shows that the residual renal function in PD patients contributes significantly to the maintenance of phosphate balance and may explain the lower prevalence of valve calcification in PD patients compared with HD patients in the period up to first 3 years under renal replacement therapy.