Special chewing gum may help dialysis patients

NEW YORK (Reuters Health) - High levels of phosphate in the blood is a common problem for patients who receive dialysis for kidney failure, but new research suggests that the use of a special chewing gum may help combat this problem.

High phosphate levels can lead to bone loss. To reduce their levels, dialysis patients use phosphate binders -- drugs that are taken with food and designed to prevent phosphate from being absorbed into the body.

Traditional phosphate binders achieve normal phosphate levels in only half of dialysis patients, study co-author Dr. Lorenzo A. Calo, from the University of Padova, Italy, and colleagues note. Binding of phosphate in the saliva during periods of fasting may help more patients achieve normal levels.

As reported in the Journal of the American Society of Nephrology, the researchers first assessed the phosphate-binding ability of the natural polymer chitosan. After showing that chitosan did have moderate binding ability, the researchers treated 13 dialysis patients with chitosan-containing chewing gum.

The subjects used the gum twice a day during fasting periods and also continued to receive their prescribed phosphate binders.

At 2 weeks, saliva and blood levels of phosphate had dropped 55 and 31 percent, respectively, compared with levels at the start of the study. After stopping the gum, saliva and blood phosphate levels returned to their initial values 15 and 30 days later, respectively.

The use of the gum had no effect on blood levels of calcium or parathyroid hormone, both of which play a key role in maintaining healthy bones, the report indicates.

The addition of phosphate-binding gum to phosphate binders may be a useful approach to reduce high phosphate levels in hemodialysis patients, the authors conclude.

SOURCE: Journal of the American Society of Nephrology, March 2009.