Effects of sildenafil and vardenafil on erectile dysfunction and health-related quality of life in haemodialysis patients: a prospective randomized crossover study.

BACKGROUND: Erectile dysfunction (ED) is prevalent in end-stage renal disease (ESRD) and has been associated with impaired health-related quality of life (HRQoL). HRQoL, in turn, is related to morbidity and mortality in ESRD patients. Previous studies have shown improved HRQoL with ED treatment using sildenafil and vardenafil. However, no study has examined the effects of sildenafil or vardenafil on HRQoL in impotent ESRD patients. Furthermore, vardenafil has never been tested and its safety profile has not been determined in ESRD patients. The aim of this randomized crossover study was to compare the effects of sildenafil and vardenafil on measures of HRQoL and on ED scores as well as to determine the safety profile of vardenafil in ESRD patients. METHODS: In 32 haemodialysis patients with impotence, ED and HRQoL were evaluated by the International Index of Erectile Function (IIEF-5) and the 36-item Short-Form Health (SF-36) surveys, respectively. Patients were randomized into sildenafil and vardenafil groups. After a 4-week treatment and 2-week washout periods, crossover was performed and an additional 4-week treatment was administered. IIEF-5 and SF-36 surveys were given before and after each treatment period. Adverse effects were evaluated by interview. Friedman tests and Bonferroni-adjusted Wilcoxon signed-rank tests were used to compare groups and for post hoc analysis, respectively. RESULTS: IIEF-5 and SF-36 scores were significantly improved by both sildenafil and vardenafil compared to pretreatment values. There were no differences between sildenafil and vardenafil with respect to the studied parameters. Adverse effect profiles were also similar. No patient dropped out because of side effects. CONCLUSIONS: Sildenafil and vardenafil caused similar improvements in ED and HRQoL in haemodialysis patients. Vardenafil was well tolerated in our patient population.

Relationship of ENOS and RAS gene polymorphisms to initial peritoneal transport status in peritoneal dialysis patients.

BACKGROUND: Peritoneal membrane permeability is of major importance for adequate dialysis and fluid balance in peritoneal dialysis (PD) therapy. The peritoneal capillary endothelium plays a key role in peritoneal transport. Nitric oxide derived from endothelial cells is related to the maintenance of vascular permeability. We investigated the relationship between the endothelial nitric oxide synthase (ENOS) gene polymorphism, the renin-angiotensin system (RAS) gene polymorphisms, and initial peritoneal transport type in PD patients. METHODS: This study included 74 incident continuous ambulatory PD patients. The ENOS gene polymorphism was identified at the 4a/b variable number of tandem repeats in intron 4. Genetic polymorphisms of the renin-angiotensin system were performed for the angiotensin-converting enzyme I/D, angiotensinogen M235T, and angiotensin II type 1 receptor A1166C and type 2 receptor C3123A by polymerase chain reaction. Patients were divided into two groups according to the initial peritoneal equilibration test results performed within 3 months of PD therapy: group 1 consisted of high/high average transporters (n = 41), and group 2 consisted of low/low average transporters (n = 33). RESULTS: Demographic, clinical, and laboratory data were similar between the two groups (p > 0.05). Group 1 had a significantly higher prevalence of the ENOS b/b genotype than group 2 (78% vs. 48.5%, p < 0.008). In contrast, group 2 had a significantly greater prevalence of the ENOS a/a+a/b genotype than group 1 (51.5% vs. 22%, p < 0.008). Genetic polymorphisms of the renin-angiotensin system were not associated with initial peritoneal transport type (p > 0.05). CONCLUSIONS: Modulation of the nitric oxide activity via the ENOS a/b polymorphism may have a considerable effect on the basal peritoneal permeability.

Comparison of erythropoietin resistance in hemodialysis patients using calcitriol, cinacalcet, or paricalcitol.

The erythropoiesis-stimulating agent (ESA) hyporesponsiveness index (EHRI) calculated as the weekly dose of EPO divided by weight (kg) divided by hemoglobin level (g/dL) has been considered useful to assess ESA resistance. Recent evidence suggests that active vitamin D, cinacalcet, and paricalcitol use may be related with lower ESA resistance. We conducted this observational cross-sectional study to investigate ESA resistance calculated by the EHRI among patients using calcitriol, cinacalcet, and paricalcitol. Participants underwent a medical history taken, physical examination, measurement of biochemical analysis, calculation of dialysis adequacy, and EHRI. Sixty-five patients did not receive any treatment regarding vitamin D, paricalcitol, and cinacalcet (group 1), 41 were taking only vitamin D (group 2), 50 were taking only paricalcitol (group 3), 19 were taking only cinacalcet (group 4), and 21 were taking paricalcitol + cinacalcet (group 5). The EHRI values for groups 1, 2, 3, 4, and 5 were 11.36 ± 8.72, 11.58 ± 5.72, 8.29 ± 5.54, 9.49 ± 4.61, and 8.91 ± 4.44 respectively (P =.034). Post hoc analysis showed that the EHRI differed between group 1 and group 3 (P =.017) and between group 2 and group 3 (P =.006). In linear regression analysis, use of paricalcitol was independently associated with EHRI. In conclusion, paricalcitol use was associated with lower EHRI levels as a measure of ESA resistance.

The booster phenomenon in 2-step tuberculin skin testing of patients receiving long-term hemodialysis.

BACKGROUND: Tuberculosis remains a significant health problem for patients receiving long-term hemodialysis (HD). The tuberculin skin test (TST) is an important method for detecting Mycobacterium tuberculosis infection. This study examined the significance and frequency of the booster phenomenon in serial TST of HD patients. METHOD: Fifty-three outpatients in a hospital-based HD center in Turkey were screened for tuberculosis with the TST between August and October 1999. To determine the frequency of booster phenomenon, patients with less than 10 mm indurations to the initial TST were given a second test 7 days later. RESULTS: Nineteen (35.8%) of 53 patients had a significant tuberculin reaction (> or = 10 mm) on the initial TST. The booster effect was detected in 10 (29.4%) of 34 patients who had a negative reaction (< 10 mm) to the initial test. Overall, 29 (54.7%) patients showed a significant reaction on both tests. CONCLUSIONS: These results showed significant rates of TST positivity and the booster effect in this HD center.

The relationship between aortic knob width and various demographic, clinical, and laboratory parameters in stable hemodialysis patients.

Accelerated atherosclerosis is very common in hemodialysis (HD) patients and is related to morbidity and mortality. The aortic knob width (AKW), which can easily be calculated on chest radiographs has also been found to be related to atherosclerosis in patients with normal renal function. The importance of AKW in HD patients is not known. The current study is aimed to investigate factors associated with increased AKW in HD patients. The study participants had their medical history taken and a physical examination conducted, with calculation of dialysis adequacy and AKW. AKW was calculated from the chest x-rays at the end of the dialysis session, when the patients were in their dry weight. A total of 91 HD patients and 65 patients with normal renal function (as a control group) were included. The mean of the AKW was 35.0±5.8 mm in HD patients and 26.6±4.3 mm in the control group (P<0.0001). Stepwise linear regression analysis of both groups combined revealed that age (P: 0.001), male gender (P<0.0001), systolic BP (P<0.0001), presence of HD treatment (P: 0.016), and albumin levels (P: 0.021) were inde-pendently related with increased AKW. On the other hand, in HD patients stepwise linear regression showed that age (P<0.0001), pre-dialysis systolic BP (P: 0.003), male gender (P<0.0001), being a non-smoker (P: 0.002), total cholesterol (P: 0.001), and intact parathormone levels (P: 0.005) were independently associated with increased AKW. In conclusion, AKW is increased in HD patients when compared with the normal population. These preliminary findings may enhance the use of chest radiography as a screening method, and if confirmed, can assist risk stratification in HD patients.

The relationship between red cell distribution width with erythropoietin resistance in iron replete hemodialysis patients.

BACKGROUND: Recently, erythropoietin resistance (ER) has been shown to be related with cardiovascular and overall mortality in hemodialysis (HD) patients. Red blood cell distribution width (RDW) has also shown to be associated with cardiovascular and all cause mortality in general population. Thus in the current study we tested the hypothesis that RDW and erythropoietin resistance as determined by erythropoiesis stimulating agents (ESA) hyporesponsiveness index (EHRI) may be related with each other in iron replete HD patients. METHODS: Study participants underwent medical history taking, physical examination, calculation of dialysis adequacy and biochemical analysis. EHRI was calculated as the weekly dose of EPO divided by per kilogram of body weight divided by the hemoglobin level. RESULTS: Two separate analyses were performed. In the first analysis performed in 94 HD patients; the stepwise linear regression analysis revealed that being female (P=0.031), HD duration (P=0.021), presence of diabetes mellitus (P=0.008), RDW (P=0.023), and predialysis sodium (P=0.05) were independently related with logarithmically converted EHRI. We made second analysis after 4 months. The second analysis revealed that when compared to first EHRI, the EHRI was increased in 40, unchanged in one and decreased in 40 patients The second stepwise regression analysis also showed that the independent relationship with RDW and EHRI was persisted (ß=0.050, CI: 0.022-0.078, P=0.001). CONCLUSION: Red blood cell distribution width was independently related with EHRI in iron replete HD patients.

Dental erosion in chronic renal failure.

Dental erosion is a common oral finding in chronic renal failure and may develop due to extrinsic and/or intrinsic causes. The aim of this study was to compare the salivary calcium and phosphorus levels, salivary flow rate, salivary buffer capacity, salivary pH, serum calcium and phosphorus levels and parathyroid hormone levels in chronic renal failure patients with and without dental erosion. Twenty-four men and 19 women who had had chronic renal failure for at least 2 years were studied. Twenty-two subjects displayed erosion-like patterns on their teeth and the other 21 patients showed no signs of erosion. Two closely age- and sex-matched control groups (control groups 1 and 2) were enrolled in this study because of the age disparity between the erosion and non-erosion groups. The data were analyzed by Mann-Whitney U test, Student t test, Pearson's and Spearman's correlation tests. None of the comparisons were statistically different between the erosion and non-erosion groups. There were statistically significant differences in salivary calcium (P < 0.01) and phosphorus (P < 0.01) levels, serum phosphorus level (P < 0.01) and serum PTH level (P < 0.01) for the erosion group and control group 1 and also for the non-erosion group and control group 2. There was also a significant difference in salivary flow rate (P < 0.05) for the erosion group and control group 1. There was a positive significant correlation between saliva buffer capacity and salivary phosphorus level (r = 0.454, P < 0.05) in the erosion group.

Early and intensive fluid replacement prevents acute renal failure in the crush cases associated with spontaneous collapse of an apartment in Konya.

BACKGROUND: Crush syndrome developing as a result of earthquake and other natural disasters has been investigated from many angles to date. Data are scarce, however, on cases associated with the spontaneous crash of buildings. This study presents the results on seven rhabdomyolysis patients treated in our clinics out of nine casualties who were rescued from the rubble of Zümrüt apartment after the building collapsed suddenly and spontaneously. METHODS: As a result of the sudden, spontaneous collapse of the 10-floor Zümrüt apartment in Konya at 20:15 hours on February 2, 2004, 92 out of a total of 121 persons who were inside the building lost their lives, and 29 casualties were rescued from the rubble. Nine hospitalized patients had crush syndrome, and a prophylactic mannitol-bicarbonate cocktail was started in all at admission. RESULTS: The time they remained entrapped under the rubble was 11.1 +/- 7.3 (5-24 hours) on average. The highest CPK level of the patients was 79049 +/- 75374 u/L (17478-223600 u/L), observed on the median day 1.7 +/- 1.1 (days 1-4) following the incident. ARF developed in only two cases (28.6%) owing to the prophylactic mannitol-bicarbonate cocktail administered to prevent ARF, and because of hyperpotassemia, hemodialysis (HD) treatment was administered to these patients. One patient required two sessions of HD, and another required four. In both patients who received HD treatment, the level of potassium was in excess of 7 mEq/L. A total of eight fasciotomies were performed on five (71.4%) of the seven patients with crush syndrome. Five of the fasciotomies (62.5%) were performed on two of our patients who required HD treatment. None of our patients with crush syndrome developed permanent kidney damage, and no mortality occurred. CONCLUSION: It was deduced that rapid fluid therapy accompanied by the prophylactic administration of mannitol-bicarbonate are largely effective in preventing the development of ARF in cases with crush syndrome resulting from disasters.