Dialysis patients do better at high altitude - study

By Will Dunham

WASHINGTON (Reuters) - Dialysis patients who live at higher altitudes survive severe kidney disease better than patients living at lower elevations, thanks to changes in the body at greater elevations, researchers said on Tuesday.

Compared to patients living close to sea level, those at elevations of 4,000 to 6,000 feet (1,200 to 1,800 metres) have a 12 percent better survival rate after five years, and those above 6,000 feet have a 15 percent better rate, the researchers said.

In fact, survival rates for patients with end-stage kidney disease who have dialysis rose steadily as the altitude of where they lived increased, the researchers wrote in the Journal of the American Medical Association.

Dialysis treatment does some things that a failing kidney no longer can do. These include removing waste, salt and extra water from the body, maintaining safe levels of certain chemicals in the blood and helping control blood pressure.

"The prognosis once you have end-stage renal disease and require dialysis is really grim. It compares to having certain types of cancer," Dr. Wolfgang Winkelmayer of Brigham and Women's Hospital and Harvard Medical School in Boston, who led the study, said in a telephone interview.

The main reason for kidney failure in the United States is type 2 diabetes, which is on the rise as more people become obese.

"Once a person reaches end-stage renal disease, the only treatment options are either to undergo dialysis or kidney transplant," Winkelmayer added.

The researchers examined data on 804,812 U.S. dialysis patients, figuring their altitude using their postal zip code.