The relation between hemoglobin variability and carotid intima-media thickness in chronic hemodialysis patients.

PURPOSE: Hemoglobin variability is a common problem among hemodialysis patients. We have previously demonstrated an association between Hb variability and left ventricular mass index. In this study, we investigated a possible relation between Hb variability and carotid intima-media thickness (CIMT). METHODS: Twelve-month hemoglobin (Hb) values of 135 patients on maintenance hemodialysis were examined retrospectively. The range of 11-12 gr/dl was accepted as normal according to the KDOQI guidelines. Hemoglobin levels were classified as: Hb < 11 gr/dl:Low, Hb = 11-12 gr/dl:Normal and Hb > 12 gr/dl:High. According to 12-month Hb trajectory, the patients were divided into three groups: low-normal (LN), normal-high (NH) and low-high (LH). The CIMT measurements were taken on common carotid arteries bilaterally, and the average of these measurements were taken. The groups were compared in terms of CIMT measurements, demographic and laboratory features. RESULTS: The LN, NH and LH groups were similar in terms of age, gender, incidence of diabetes mellitus, hypertension and cardiovascular diseases. Duration of hemodialysis, hemodialysis adequacy, serum lipids and CaxP products were also similar among the groups. The mean CIMT value was 0.601 ± 0.107, 0.744 ± 0.139 and 0.604 ± 0.134 mm in the LN, LH and NH groups, respectively (p < 0.001). CIMT was significantly higher in LH than in the other two groups. CONCLUSIONS: In our study, when the three groups with similar risk factors for atherosclerosis were examined, we found that the LH group with the highest hemoglobin variability has the highest CIMT. This study is the first study to demonstrate that Hb variability is associated with an increase in CIMT in HD patients.

Effect of hemoglobin variability on mortality and some cardiovascular parameters in hemodialysis patients.

BACKGROUND AND OBJECTIVES: Most hemodialysis patients show hemoglobin fluctuations between low-normal and high levels. This hemoglobin variability may cause left ventricle hypertrophy and may increase mortality as well. Recently, many studies were designed to evaluate the effect of hemoglobin variability on mortality but results were conflicting. We aimed to investigate the effect of hemoglobin variability on mortality and some cardiovascular parameters in hemodialysis population. DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS: Hundred and seventy-five prevalent hemodialysis patients classified into three hemoglobin variability groups according to their hemoglobin levels throughout 24 month observation period: Low-Normal, Low-High, Normal-High. Groups were compared in terms of laboratory, demographical data and mortality rates, initial and the end of 24 month echocardiographic data. Initial and last echocardiographic data were compared within groups in terms of left ventricle mass index increase. RESULTS: Mortality rates and cardiovascular risk factors such as coronary heart disease, diabetes mellitus and hypertension that may affect mortality were same between three groups. There was no significant difference between three groups in terms of echocardiographic and laboratory parameters. Only Low-High group showed significant increase on left ventricle mass index when initial and last echocardiographic parameters were compared. CONCLUSIONS: Consistent with previous studies, we found that most of the patients exhibited hemoglobin variability and our study is consistent with some of the studies that did not find any relationship between hemoglobin variability and mortality. Firstly, in this study based on objective data, it was shown that hemoglobin variability has adverse effect on left ventricle geometry independent from anemia.

Mortality and cardiovascular events in online haemodiafiltration (OL-HDF) compared with high-flux dialysis: results from the Turkish OL-HDF Study.

BACKGROUND: Online haemodiafiltration (OL-HDF) is considered to confer clinical benefits over haemodialysis (HD) in terms of solute removal in patients undergoing maintenance HD. The aim of this study was to compare postdilution OL-HDF and high-flux HD in terms of morbidity and mortality. METHODS: In this prospective, randomized, controlled trial, we enrolled 782 patients undergoing thrice-weekly HD and randomly assigned them in a 1:1 ratio to either postdilution OL-HDF or high-flux HD. The mean age of patients was 56.5 ± 13.9 years, time on HD 57.9 ± 44.6 months with a diabetes incidence of 34.7%. The follow-up period was 2 years, with the mean follow-up of 22.7 ± 10.9 months. The primary outcome was a composite of death from any cause and nonfatal cardiovascular events. The major secondary outcomes were cardiovascular and overall mortality, intradialytic complications, hospitalization rate, changes in several laboratory parameters and medications used. RESULTS: The filtration volume in OL-HDF was 17.2 ± 1.3 L. Primary outcome was not different between the groups (event-free survival of 77.6% in OL-HDF versus 74.8% in the high-flux group, P = 0.28), as well as cardiovascular and overall survival, hospitalization rate and number of hypotensive episodes. In a post hoc analysis, the subgroup of OL-HDF patients treated with a median substitution volume >17.4 L per session (high-efficiency OL-HDF, n = 195) had better cardiovascular (P = 0.002) and overall survival (P = 0.03) compared with the high-flux HD group. In adjusted Cox-regression analysis, treatment with high-efficiency OL-HDF was associated with a 46% risk reduction for overall mortality {RR = 0.54 [95% confidence interval (95% CI) 0.31-0.93], P = 0.02} and a 71% risk reduction for cardiovascular mortality [RR = 0.29 (95% CI 0.12-0.65), P = 0.003] compared with high-flux HD. CONCLUSIONS: The composite of all-cause mortality and nonfatal cardiovascular event rate was not different in the OL-HDF and in the high-flux HD groups. In a post hoc analysis, OL-HDF treatment with substitution volumes over 17.4 L was associated with better cardiovascular and overall survival.

Effects of thrice weekly nocturnal hemodialysis on arterial stiffness.

OBJECTIVE: In this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis. METHODS: Sixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial-carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month. RESULTS: Mean age of the patients was 49±11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57±47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0±0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium-phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02±2.51 m/s to 9.61±2.39 m/s and from 28.8±10.3% to 26.2±12.1%; p=0.008 and p=0.04, respectively). While augmentation index increased in the CHD group (28.0±9.4 to 31.0±10.7%, p=0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135±28 to 143±25%, p=0.01 and from 294±34 ms to 281±34 ms, p=0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio. CONCLUSIONS: These data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.

Restless legs syndrome in hemodialysis patients: association with depression and quality of life.

PURPOSE: The prevalence of restless legs syndrome (RLS) ranging from 6.6% to 83% has been reported in different case series. The pathophysiology of RLS in uremia is still unclear. The aim of this study was to assess the frequency of RLS in the hemodialysis patients and to explore depression and associated detrimental impact on quality of life. METHODS: The diagnosis of RLS was made using the criteria of the International Restless Legs Study Group. The polyneuropathy was diagnosed according to clinical signs and symptoms. Each subject completed three questionnaires: Beck Depression Inventory, Short Form-36 Quality of Life Scale, and the Epworth Sleepiness Scale (ESS). Biochemical parameters including hemoglobin, serum ferritin, and Kt/V index were collected. The data of the patients with and without RLS or clinical polyneuropathy (PNP) were compared. RESULTS: There were 41 male and 40 female patients. RLS, PNP, and high ESS scores were seen in 12%, 47%, and 7% of hemodialysis patients, respectively. Beck depression inventory scores were high in patients with RLS when compared to those without (28.9 ± 9, p = 0.007). General health score in the RLS patients, physical functioning score in the PNP patients were significantly lower (GH, 20.7; p = 0.036; PF, 10.5; p < 0.005). We did not observe any association between hemoglobin, ferritin levels, and Kt/V index in the RLS patients. However, Kt/V index in the PNP patients were low. CONCLUSIONS: The frequency of RLS in hemodialysis patients was lower than that reported from similar studies in other countries. The presence of RLS and PNP in hemodialyzed patients negatively affects quality of life, and RLS contributes to occurrence of depression.

The prevalence and predictors of atrial fibrillation in hemodialysis patients.

OBJECTIVES: The aim of this study was to determine the prevalence of atrial fibrillation in long-term hemodialysis patients and to identify clinical and echocardiographic risk factors. STUDY DESIGN: The study included 183 patients (93 males, 90 females; mean age 52+/-17 years) who had been on long-term hemodialysis treatment (mean 41.6+/-39.8 months) and had preserved systolic function. Atrial fibrillation was determined electrocardiographically and the patients were divided into two groups depending on the presence or absence of atrial fibrillation. Conventional and tissue Doppler echocardiographic examinations were performed on interdialytic days. Clinical, laboratory, and echocardiographic parameters were compared. RESULTS: Twenty-four patients (13.1%) had atrial fibrillation. Patients with atrial fibrillation significantly differed in terms of higher age (64.9+/-9.8 vs. 49.9+/-16.6 years; p<0.001), higher frequency of coronary artery disease (37.5% vs. 10.7%; p=0.008), and lower serum albumin level (3.6+/-0.4 vs. 3.9+/-0.5 mg/dl; p=0.015). Echocardiographic examination showed significantly increased left and right atrial diameters (p<0.05), higher incidence of mitral and/or aortic calcification (p=0.033), increased systolic pulmonary artery pressure (38.1+/-6.1 vs. 28.5+/-5.5 mmHg, p<0.001) and E/E' ratio (11.8+/-3.8 vs. 8.8+/-4.7, p=0.008) in patients with atrial fibrillation. In multivariate logistic regression analysis, age (OR 1.09; 95% CI 1.00-1.17; p=0.036) and right atrial diameter (OR 1.19; 95% CI 1.05-1.35; p=0.008) were independent risk factors for the development of atrial fibrillation. CONCLUSION: Our findings highlight age and right atrial diameter as independent predictors of atrial fibrillation in hemodialysis patients. In addition, the E/E' ratio and pulmonary artery pressure may be considered new risk factors of atrial fibrillation in this population.

Prevalence of and factors affecting pulmonary hypertension in hemodialysis patients.

BACKGROUND: Pulmonary hypertension (PH) has been reported to be high among end-stage renal disease (ESRD) patients. OBJECTIVES: The aim of this study was to investigate the role of arteriovenous fistula (AVF) flow in the pathogenesis of PH and the prevalence of PH in patients with chronic renal failure (CRF) and to suggest other possible etiologic factors. METHODS: The prevalence of PH was prospectively estimated by Doppler echocardiography in 116 ESRD patients on regular hemodialysis (HD). Laboratory and clinical variables were compared between patients with and without PH (groups 1 and 2, respectively). PH was defined as systolic pulmonary artery pressure (SPAP) over 30 mm Hg. Patients with PH underwent further evaluation by 2 pulmonologists. AVF flow was measured by Doppler ultrasonography. Blood tests including arterial blood gases, hemoglobin, serum calcium, phosphorus and parathyroid hormone were determined. RESULTS: PH was found in 25 (21.6%) patients (group 1) with an SPAP of 37.9 ± 2.8 mm Hg. Mean AVF flow was increased (1,554 ± 207.60 ml/min) in group 1. Left ventricular ejection fraction (LVEF) was significantly different between the 2 groups (55.3 ± 11.5 and 64.4 ± 40, respectively; p < 0.05). Neither significant primary lung disease nor parenchymal lesions were detected in group 1. PH showed a significant difference for cigarette smoking (p < 0.05). In group 1 the prevalence of cigarette smoking was higher. The main etiology of CRF was diabetes mellitus with a ratio of 44% in group 1. CONCLUSION: Our study demonstrated a surprisingly high prevalence of PH among patients receiving long-term HD. PH was related to high AVF flow, low LVEF and cigarette smoking. AVF flow and cigarette smoking are important correctable causes of PH. Early detection is important in order to avoid the serious consequences.

Long-term efficacy of pegylated interferon alpha-2a in HCV-positive hemodialysis patients.

BACKGROUND AND AIM: Hepatitis C virus (HCV) is prevalent in hemodialysis (HD) patients. The current "best therapy" for HCV-positive hemodialysis patients is not known. The aim of the present study was to evaluate the long-term efficacy of pegylated interferon (PEG-IFNalpha-2a) in HCV-positive hemodialysis (HD) patients. MATERIALS AND METHODS: Twenty-five HCV-RNA-positive hemodialysis patients were included into the study. Twelve patients were allocated to the PEG-IFN treatment group (group 1). Six refused the therapy, and seven were not candidates for kidney transplantation and were allocated to the control group (group 2). All patients underwent chronic hemodialysis treatment for end-stage renal disease during the study period. Group 1 patients received PEG-IFN alpha-2a at a dose of 135 mug weekly for 48 weeks. The patients were prospectively followed up for a period of 192 weeks. Biochemical and virological responses were evaluated at 144 weeks after the completion of therapy. Results. Two patients in group 1 and five patients in group 2 died during 144 weeks of follow-up. SVR was observed in six patients (50%) in group 1 and one patient (1/13) (7.7%) in group 2. ALT levels were normal in 8/10 (80%) in group 1 and in 5/7 (70%) in group 2. CONCLUSION: In summary, our data showed that treatment of chronic HCV infection in dialysis patients with PEG-IFN alpha-2a at a dose of up to 135 mug weekly was well tolerated. Furthermore, SVR was achieved in half of patients at the end of 144 weeks of follow-up. Our results are encouraging for the administration of PEG-IFN alpha-2a in HCV-positive HD patients waiting for kidney transplantation.

Efficacy and tolerability of pegylated-interferon alpha-2a in hemodialysis patients with chronic hepatitis C.

BACKGROUND AND AIM: Hepatitis C virus (HCV) is prevalent in hemodialysis (HD) patients. These patients experience more side-effects with antiviral treatment. The aim of the present study was to evaluate the efficacy and tolerability of pegylated interferon (PEG-IFN) alpha-2a in chronic hemodialysis patients with chronic hepatitis C. METHODS: Twenty-five patients were included into the study. All of the patients were interferon naive, anti-HCV antibodies positive and polymerase chain reaction HCV-RNA positive. Twelve of the patients received PEG-IFN alpha-2a at a dose of 135 microg weekly for 48 weeks (Group 1). The remaining 13 patients who received no specific treatment were used as controls (Group 2). The patients were prospectively followed up for a period of 18 months. Biochemical and virological responses were evaluated at the end of the study period (end-of-treatment response) and 6 months after the completion of therapy (sustained response). RESULTS: Virological end-of-treatment response was observed in 10 patients (83.4%) in Group 1 and one patient (7.7%) in Group 2 (P < 0.001). Sustained virological response was observed in nine patients (75%) in Group 1 and one patient (7.7%) in Group 2 (P < 0.001). Alanine aminotransferase (ALT) levels were initially increased in seven patients in Group 1 and normalized in five of these patients at the end of the treatment and sustained biochemical response was 71.4%. In contrast, ALT levels in Group 2 were initially high in five patients and normalized in two of them (40%) at the end of the 48 weeks. Even if most of the patients experienced several side-effects (anemia 75%, fatigue 58.3%, thrombocytopenia 33.3% and leukopenia 33.3%), they did not impose the discontinuation of the treatment. CONCLUSION: The present study showed that PEG-IFN alpha-2a for 48 weeks is efficacious and well tolerated in hemodialysis patients with HCV.

Impression cytology changes and corneoconjunctival calcification in patients with chronic renal failure.

OBJECTIVE: To evaluate the relationship between corneoconjunctival calcification and conjunctival squamous metaplasia in patients with chronic renal failure (CRP). STUDY DESIGN: We studied impression cytology in 45 CRF patients on regular hemodialysis and 30 age- and sex-matched controls. Specimens were obtainedfrom the temporal bulbar conjunctiva using cellulose acetate filter paper. The samples were fixed in a mixture of 70% ethyl alcohol, 37% formaldehyde and glacial acetic acid and then stained with a combination of periodic acid- Schiff and Gill's modified Papanicolaou stain and graded by a masked observer. Corneoconjunctival calcification was graded by the Porter-Crombie classification. RESULTS: Of 45 study patients, 4 (9%) disclosed grade 0, 23 (51%) grade 1, 14 (31%) grade 2 and 4 grade 3 (9%) impression cytology changes. There was a statistically significant difference between the patient and control groups (p < 0.001). Calcium deposits were more frequent and extensive in CRF patients than in controls (p = 0.01). There was no correlation between impression cytology and calcium deposit grades (p = 0.128). However the presence of conjunctival inflammation correlated with the existence of extensive squamous metaplasia (p < 0.001). CONCLUSION: The severity of conjunctival changes in CRF patients on regular hemodialysis are not related to calcium deposition but to acute conjunctival inflammation.