Kidney Disease Research Updates
FHN Trial Group Finds Frequent Hemodialysis Promotes Heart Health
Additional Studies Have Mixed Results on Physical Performance
Most patients on hemodialysis have a standard schedule of three sessions a week for 3 to 5 hours each session. While this schedule keeps patients alive, many still have serious health problems related to their kidney failure, such as heart disease. And the mortality rate for patients on hemodialysis is high. The Frequent Hemodialysis Network (FHN) Trial Group was formed in 2005 to explore whether alternative schedules with more frequent hemodialysis sessions would reduce the mortality and morbidity associated with hemodialysis.
Supported by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the FHN Trial Group developed two separate trials. In the Daily Trial, one group of participants received hemodialysis six times a week for 1.5 to 2.75 hours a session while another group received the standard three sessions a week. In the Nocturnal Trial, one group of participants received dialysis for 6 to 8 hours overnight for six nights a week while, again, the other group received the conventional hemodialysis treatment.
Results of the two trials are now being reported in a wide range of medical journals. The journal articles focus on many different aspects of frequent hemodialysis, including its effect on physical performance, body composition, and blood pressure control. One significant article deals with left ventricular hypertrophy (LVH).
Frequent Hemodialysis and LVM
Christopher Chan, M.D., of the University Health Network, Ontario, Canada, led a group that examined the effect of frequent hemodialysis on left ventricular mass (LVM). Enlargement of muscles in the left ventricle, one of the heart’s pumping chambers, is a sign of heart disease. In the March 2012 issue of Circulation: Cardiovascular Imaging, Dr. Chan and colleagues reported that participants receiving daily hemodialysis had a significant reduction in LVM, and those who already had the greatest LVM at baseline received the greatest benefit. Participants receiving long, overnight hemodialysis did not achieve a statistically significant LVM reduction, although the results trended in that direction. Participants receiving conventional hemodialysis saw no LVM benefit.
Dr. Chan and colleagues looked at other clinical factors that may have contributed to the beneficial effect of daily hemodialysis, including volume removal, blood pressure, and solute clearance. Changes in LVM were associated most closely with changes in blood pressure and were not significantly associated with the other clinical factors. Dr. Chan and colleagues concluded that frequent hemodialysis reduces LVM, possibly with the help of improved blood pressure control.
In additional studies, the FHN Trial Group found that more frequent hemodialysis did not have significant effects on measures of nutritional status or objective measures of physical performance, although participants reported that they perceived an improvement in their performance. Additional benefits included better phosphorus and blood pressure control. Researchers also found that participants who received daily or nocturnal hemodialysis had more problems with their vascular access, the modified blood vessel where needles are inserted for dialysis.
With these mixed results, researchers have concluded that more frequent hemodialysis could be of benefit to some people.
NIH Publication No. 13–4531
Page last updated January 31, 2013