Vitamin K1 and progression of cardiovascular calcifications in hemodialysis patients: the VitaVasK randomized controlled trial.

Background: Cardiovascular calcifications are prevented by matrix Gla protein (MGP), a vitamin K-dependent protein. Haemodialysis patients exhibit marked vitamin K deficiency. The randomized, prospective, open-label, multicentre VitaVasK trial analysed whether vitamin K1 supplementation reduces progression of coronary artery calcifications (CACs) and thoracic aortic calcifications (TACs). Methods: Patients with pre-existing CACs were randomized to continue on standard care or to additionally receive 5 mg of vitamin K1 orally thrice weekly. Hierarchically ordered primary endpoints were progression of TAC and CAC in computed tomography scans at 18 months. Linear mixed effects models with repeated measures at baseline and 12 and 18 months assessed treatment effects after adjusting for study site. Results: Of 60 randomized patients, 20 dropped out for reasons unrelated to vitamin K1, resulting in 23 control and 17 vitamin K1 patients. The trial was stopped early due to slow recruitment. At 18 months, the average TAC progression was 56% lower in the vitamin K1 compared with the control group (p = .039). CAC significantly progressed within the control group, but not within the vitamin K1 group. Average progression at 18 months was 68% lower in the vitamin K1 compared to the control group (P = .072). Vitamin K1 reduced plasma levels of pro-calcific uncarboxylated MGP by 69% at 18 months. No treatment-related adverse events were noted. Conclusion: Vitamin K1 intervention is a potent, safe and cost-effective approach to correct vitamin K deficiency and to potentially reduce cardiovascular calcification in this high-risk population.

Any use for alternative lock solutions in the prevention of catheter-related blood stream infections?

The prevention of catheter-related blood stream infections (CRBSI) in hemodialysis (HD) patients remains a challenge because of high morbidity and mortality associated to CRBSI. Alternative locking solutions (ALS) containing an antithrombotic substance with additional antimicrobial or antibiofilm properties (citrate, ethylenediaminetetraacetic acid [EDTA], 70% ethanol, thrombolytics) with or without the addition of molecules with specific antimicrobial activity (antibiotics, taurolidine, paraben-methylene-blue) has been proposed with the aim to prevent or eradicate intraluminal biofilm colonization and subsequent CRBSI. In this review, we examine the available evidence concerning their efficacy and potential side effects, in order to determine whether ALS should be implemented widely or only in selected cases.

Potassium-binding resins: Associations with serum chemistries and interdialytic weight gain in hemodialysis patients.

BACKGROUND: Although potassium-binding sodium-based resins (K resins) have been prescribed to treat hyperkalemia for 50 years, there have been no large studies of their effects among hemodialysis (HD) patients. METHODS: Data from 11,409 patients in the Dialysis Outcomes and Practice Patterns Study in Belgium, Canada, France, Italy, and Sweden (nations where ≥5% of patients were prescribed a sodium- based K resin; seven other countries had <5% use) between 2002 and 2011 were analyzed. Linear mixed models examined associations between K resin use and interdialytic weight gain (IDWG) and serum electrolyte concentrations. Mortality was analyzed using Cox regression. An instrumental variable approach was used to partially account for unmeasured confounders. RESULTS: The K resin prescription rate was 20% overall. As hypothesized, patients prescribed a K resin had greater IDWG and higher serum bicarbonate, phosphorus, and sodium (but not calcium) concentrations. Patients prescribed a K resin had higher serum K levels, but serum K levels were lower in an instrumental variable analysis limiting treatment by indication bias. K resin use was not associated with mortality risk. CONCLUSION: We report the first large study of K resin use and associated laboratory and clinical outcomes in HD patients. The prescription rate of K resins varied dramatically by country and dialysis center. The results suggest that K resin use may effectively lower serum K, although at the expense of somewhat higher phosphatemia and greater IDWG, and had no clear association with mortality. Further study is warranted to elucidate the optimal role for K resins in modern dialysis care.