A difference between dialysate and serum sodium concentration leads to diffusive sodium transfer across the dialyzer membrane. The consequences of diffusive sodium flux into the patient can be chronic sodium overload leading to overhydration, hypertension, cardiovascular disease, and other problems. Diffusive sodium flux out of the patient can lead to intradialytic blood pressure instability. A simple strategy for alignment of dialysate and serum sodium concentrations was implemented starting in April/May 2010 in order to minimize the problems particularly associated with chronic sodium overload.

The purpose of this database analysis is to assess the impact that this operational change has had in the short, medium and long term on key clinical and laboratory parameters in the patients, including blood pressure, body weight, interdialytic weight gain, serum electrolytes, intradialytic saline administration, missed treatments, hospitalizations, medication, inflammatory markers, etc. All subjects included in the final dataset will be matched with dialysis patients receiving treatment in other dialysis clinics of the Renal Research Institute who were not subject to the operational change. This will lead to the development of a matched cohort of equal size unexposed to dialysate to serum sodium alignment.

The analysis is planned to investigate treatment effects, and test the effects of dialysate to serum sodium alignment for interactions and associations between those laboratory and clinical parameters. The extent and magnitude of sodium alignment (the operational change) will also be assessed.

Inclusion Criteria:

• Subjects on hemodialysis

Exclusion Criteria:

• None

All subjects on hemodialysis