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Background and Objectives: Vascular calcification is a major contributor to morbidity and mortality in hemodialysis. The objective of this pilot study was to determine the feasibility, safety and efficacy of sodium thiosulfate (STS) in the progression of vascular calcification in hemodialysis patients.Methods: Chronic hemodialysis patients underwent a battery of cardiovascular tests. Those with coronary artery calcium (Agatston scores >50) received intravenous STS after each dialysis for 5 months (n = 22) and the tests were repeated. Changes in MDCT-determined calcification were assessed as the mean annualized rate of change in 3 vascular beds (coronary, thoracic and carotid arteries) and in L1-L2 vertebral bone density.Results: Although individual analyses showed coronary artery calcification progression in 14/22 subjects, there was no progression in the mean annualized rate of change of vascular calcification in the entire group. The L1-L2 vertebral bone density showed no changes. There were no correlations between rates of progression of vascular calcification and phosphorus, fetuin or C-reactive protein levels. Changes in coronary artery calcification scores correlated with those of the thoracic aorta.Conclusion: STS treatment is feasible, appears safe and may decrease the rate of progression of vascular calcification in hemodialysis patients. A large, randomized, controlled trial is warranted. [ABSTRACT FROM AUTHOR]

The article presents a study on the effect of dipyridamole administration on arteriovenous graft stenosis in patients having hemodialysis. Thirteen United States centers were involved in the double blind, placebo controlled trial. Patients were randomly assigned to a group. Dipyridamole extended-release 200 mg was given with aspirin 25 mg orally twice a day for 4.5 years to patients with a new arteriovenous graft. Six months of follow-up was also given. The dipyridamole and aspirin reduced the risk of stenosis and improved the length of time the graft was patent.

Dialysis dose and the effect of gender and body size on outcome in the HEMO Study. Background. Gender and body size have been associated with survival in hemodialysis populations. In recent observational studies, overall mortality was similar in men and women and higher in small patients. The effect of dialysis dose in each of these subgroups has not been tested in a clinical trial. Methods. The HEMO Study was a controlled trial of dialysis dose and membrane flux in 1846 hemodialysis patients followed up for 6.6 years in 15 centers throughout the United States. We examined the effect of dialysis dose on mortality and on selected secondary outcomes in subgroups of patients. Results. Adjusting for age only, overall mortality was lower in patients with higher body weight ( P < 0.001), higher body mass index ( P < 0.001), and higher body water content determined by the Watson formula (Vw) ( P < 0.001), but was not associated with gender ( P= 0.27). The RR of mortality comparing the high dose with the standard dose group was related to gender ( P= 0.014). Women randomized to the high dose had a lower mortality rate than women randomized to the standard dose (RR = 0.81, P= 0.02), while men randomized to the high dose had a nonsignificant trend for a higher mortality rate than men randomized to the standard dose (RR = 1.16, P= 0.16). Analysis of both genders combined showed no overall dose effect (R = 0.96, P= 0.52), as reported previously. Vw was greater than 35 L in 84% of men compared with 17% of women. However, the RR of mortality for the high versus standard dose remained lower in women than in men after adjustment for the interaction of dose with Vw or with other size parameters, including weight and body mass index. Conversely, the dose effect was not significantly related to size parameters after controlling for the relationship of the dose comparison with gender. Conclusion. The data suggest that mortality and morbidity might be reduced by increasing the dialysis dose above the current standard in women but not in men. This effect was not explained by differences between men and women in age, race, or in several indices of body size. Because multiple comparisons were considered in this analysis, the role of gender on the effect of dialysis dose is suggestive and invites further study. [ABSTRACT FROM AUTHOR]

Background: The effects of the dose of dialysis and the level of flux of the dialyzer membrane on mortality and morbidity among patients undergoing maintenance hemodialysis are uncertain. Methods: We undertook a randomized clinical trial in 1846 patients undergoing thrice-weekly dialysis, using a two-by-two factorial design to assign patients randomly to a standard or high dose of dialysis and to a low-flux or high-flux dialyzer. Results: In the standard-dose group, the mean (±SD) urea-reduction ratio was 66.3±2.5 percent, the single-pool Kt/V was 1.32±0.09, and the equilibrated Kt/V was 1.16±0.08; in the high-dose group, the values were 75.2±2.5 percent, 1.71±0.11, and 1.53±0.09, respectively. Flux, estimated on the basis of beta2-microglobulin clearance, was 3±7 ml per minute in the low-flux group and 34±11 ml per minute in the high-flux group. The primary outcome, death from any cause, was not significantly influenced by the dose or flux assignment: the relative risk of death in the high-dose group as compared with the standard-dose group was 0.96 (95 percent confidence interval, 0.84 to 1.10; P=0.53), and the relative risk of death in the high-flux group as compared with the low-flux group was 0.92 (95 percent confidence interval, 0.81 to 1.05; P=0.23). The main secondary outcomes (first hospitalization for cardiac causes or death from any cause, first hospitalization for infection or death from any cause, first 15 percent decrease in the serum albumin level or death from any cause, and all hospitalizations not related to vascular access) also did not differ significantly between either the dose groups or the flux groups. Possible benefits of the dose or flux interventions were suggested in two of seven prespecified subgroups of patients. Conclusions: Patients undergoing hemodialysis thrice weekly appear to have no major benefit from a higher dialysis dose than that recommended by current U.S. guidelines or from the use of a high-flux membrane. (N Engl J Med 2002;347:2010-9.) [ABSTRACT FROM AUTHOR]