Publications (49) View all
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Article: Effect of Fluid Management Guided by Bioimpedance Spectroscopy on Cardiovascular Parameters in Hemodialysis Patients: A Randomized Controlled Trial.
Ender Hur, Mehmet Usta, Huseyin Toz, Gulay Asci, Peter Wabel, Serdar Kahvecioglu, Meral Kayikcioglu, Meltem Sezis Demirci, Mehmet Ozkahya, Soner Duman, Ercan Ok[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Fluid overload is the main determinant of hypertension and left ventricular hypertrophy in hemodialysis patients. However, assessment of fluid overload can be difficult in clinical practice. We investigated whether objective measurement of fluid overload with bioimpedance spectroscopy is helpful in optimizing fluid status. STUDY DESIGN: Prospective, randomized, and controlled study. SETTING & PARTICIPANTS: 156 hemodialysis patients from 2 centers were randomly assigned to 2 groups. INTERVENTION: Dry weight was assessed by routine clinical practice and fluid overload was assessed by bioimpedance spectroscopy in both groups. In the intervention group (n = 78), fluid overload information was provided to treating physicians and used to adjust fluid removal during dialysis. In the control group (n = 78), fluid overload information was not provided to treating physicians and fluid removal during dialysis was adjusted according to usual clinical practice. OUTCOMES: The primary outcome was regression of left ventricular mass index during a 1-year follow-up. Improvement in blood pressure and left atrial volume were the main secondary outcomes. Changes in arterial stiffness parameters were additional outcomes. MEASUREMENTS: Fluid overload was assessed twice monthly in the intervention group and every 3 months in the control group before the mid- or end-week hemodialysis session. Echocardiography, 48-hour ambulatory blood pressure measurement, and pulse wave analysis were performed at baseline and 12 months. RESULTS: Baseline fluid overload parameters in the intervention and control groups were 1.45 ± 1.11 (SD) and 1.44 ± 1.12 L, respectively (P = 0.7). Time-averaged fluid overload values significantly decreased in the intervention group (mean difference, -0.5 ± 0.8 L), but not in the control group (mean difference, 0.1 ± 1.2 L), and the mean difference between groups was -0.5 L (95% CI, -0.8 to -0.2; P = 0.001). Left ventricular mass index regressed from 131 ± 36 to 116 ± 29 g/m2 (P < 0.001) in the intervention group, but not in the control group (121 ± 35 to 120 ± 30 g/m2; P = 0.9); mean difference between groups was -10.2 g/m2 (95% CI, -19.2 to -1.17 g/m2; P = 0.04). In addition, values for left atrial volume index, blood pressure, and arterial stiffness parameters decreased in the intervention group, but not in the control group. LIMITATIONS: Ambulatory blood pressure data were not available for all patients. CONCLUSIONS: Assessment of fluid overload with bioimpedance spectroscopy provides better management of fluid status, leading to regression of left ventricular mass index, decrease in blood pressure, and improvement in arterial stiffness.American Journal of Kidney Diseases 02/2013; · 5.43 Impact Factor -
Article: Mortality and cardiovascular events in online haemodiafiltration (OL-HDF) compared with high-flux dialysis: results from the Turkish OL-HDF Study.
Ercan Ok, Gulay Asci, Huseyin Toz, Ebru Sevinc Ok, Fatih Kircelli, Mumtaz Yilmaz, Ender Hur, Meltem Sezis Demirci, Cenk Demirci, Soner Duman, Ali Basci, Siddig Momin Adam, Ismet Onder Isik, Murat Zengin, Gultekin Suleymanlar, Mehmet Emin Yilmaz, Mehmet Ozkahya[show abstract] [hide abstract]
ABSTRACT: 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.ResultsThe 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.Nephrology Dialysis Transplantation 12/2012; · 3.40 Impact Factor -
Article: Alpha-galactosidase a activity levels in Turkish male hemodialysis patients.
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ABSTRACT: Fabry disease is an X-linked lysosomal storage disorder due to deficient activity of alpha-galactosidase A (α-Gal A) leading to renal insufficiency in males. The aim of present study was to investigate the level of α-Gal A activity and to determine the prevalence of Fabry disease in a Turkish male hemodialysis population. The activity of plasma α-Gal A was measured in a group of 808 male hemodialysis patients using fluorimetric methods. Patients with low α-Gal A activity were evaluated clinically and genetic testing was carried out. A correlation with creatinine, uric acid, urea, white blood cell (WBC), and high sensitivity (hs)CRP and α-Gal A activity was also investigated. Plasma α-Gal A activity among this male population undergoing hemodialysis was 7.88 ± 5.18 µM/hour/L (0.40-55.72), significantly lower when compared to controls. No influence of creatinine, uric acid, WBC, or hsCRP on measured α-Gal A activity was reported. Two new Fabry disease patients were identified. Both were previously diagnosed with diabetes mellitus type 2. These findings provide, for the first time, data regarding the prevalence of α-Gal A deficiency (0.24%) in Turkish males receiving hemodialysis.Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 12/2012; 16(6):560-5. · 1.39 Impact Factor -
Article: Can we use CT pulmonary angiography as an alternative to echocardiography in determining right ventricular dysfunction and its severity in patients with acute pulmonary thromboembolism?
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ABSTRACT: PURPOSE: Our aim was to investigate the role of computed tomography pulmonary angiography (CTPA) in the diagnosis of right ventricular dysfunction (RVD) and massive pulmonary thromboembolism (PTE). MATERIALS AND METHODS: We retrospectively involved a total of 61 patients. In CTPAs, pulmonary arterial obstruction index (PAOI), right ventricular/left ventricular diameter ratio (RV/LV), and superior vena cava (SVC) diameters were calculated, followed by echocardiography (ECHO), and clinical results were evaluated based on the reports available. RESULTS: CTPA findings that included PAOI, RV/LV ratio, and SVC diameter were, respectively, 54.9 ± 22.7 %, 1.58 ± 0.51, and 20.3 ± 0.2 mm in patients with RVD on ECHO, whereas corresponding values were, respectively, 37.8 ± 24.2 %, 1.32 ± 0.47, and 18.4 ± 3.3 mm in those without RVD (respectively, p = 0.006, p = 0.038, and p = 0.026). PAOI was 63.3 ± 22.0 % in patients among whom massive PTE was detected and 43.1 ± 23.9 % in the group without massive PTE (p = 0.01). As for mortality; given an RV/LV ratio >1.0, this ratio had 100 % sensitivity and 35.6 % specificity, whereas given a PAOI of ≥50 %, sensitivity and specificity were 83.3 % and 57.8 %, respectively. CONCLUSION: We concluded that in the patients with PTE, PAOI ≥50 % and RV/LV >1.0 in CTPA could be helpful to demonstrate RVD.Japanese journal of radiology 11/2012; · 0.65 Impact Factor -
Article: Neither oxidized nor anti-oxidized low-density lipoprotein level is associated with atherosclerosis or mortality in hemodialysis patients.
Ebru Sevinc Ok, Fatih Kircelli, Gulay Asci, Ekrem Altunel, Muhittin Ertilav, Savas Sipahi, Devrim Bozkurt, Soner Duman, Mehmet Ozkahya, Huseyin Toz, Ercan Ok[show abstract] [hide abstract]
ABSTRACT: It is anticipated that oxidized low-density lipoprotein (oxLDL) and anti-oxLDL are associated with atherosclerosis and mortality. However, data on this issue are controversial and limited. We aimed to investigate the effect of these two markers on the extent and progression of atherosclerosis and mortality in a group of hemodialysis patients. In this prospective observational study with a follow-up of 36 months, 124 hemodialysis patients were studied. Ninety-five patients underwent carotid intima media thickness (CA-IMT) measurement by B-Mode ultrasonography both at baseline and at the end of the study. oxLDL and anti-oxLDL were measured by enzyme-linked immunosorbent assay. The extent and progression of CA-IMT, along with overall and cardiovascular mortality, were assessed. The mean age at baseline was 54.0 ± 14.8 years, 57.3% male and 20% diabetic. The mean oxLDL and anti-oxLDL levels were 8.11 ± 3.16 mU/L and 1.30 ± 0.31, respectively. Baseline mean CA-IMT was 0.82 ± 0.20 mm. Fifteen patients died during a follow-up period of 28.5 ± 6.6 months, 11 from cardiovascular causes. Only oxLDL, not anti-oxLDL, was correlated with the extent of atherosclerosis at baseline. However, both had no role in the progression of atherosclerosis. Also, in unadjusted and adjusted models, both parameters were not associated with overall or cardiovascular mortality. Neither oxLDL nor anti-oxLDL level is associated with the progression of atherosclerosis or mortality in hemodialysis patients.Hemodialysis International 04/2012; 16(3):334-41. · 1.54 Impact Factor