Methods
Participants
The cross-sectional data on part of this cohort has previously been reported.Patients 18 years or older who had been on chronic hemodialysis for more than 3 months, and were free of vascular,infectious, or bleeding complications within 1 month of recruitment who were dialyzed 3 times a week at 1 of the 4 dialysis units in Indianapolis affiliated with Indiana University, were enrolled in the study. Those who missed 2 hemodialysis treatments or more over 1month, abused drugs, had chronic atrial fibrillation, or body mass index of 40 kg/m2 or more were excluded. Patients who had a change in dry-weight or antihypertensive drugs within 2 weeks were also excluded. The study was approved by the Institutional Review Board of Indiana University and Research and Development Committee of the Roudebush Veterans Administration Medical Center, Indianapolis, and all subjects gave written informed consent.