DENVER—Hyperphosphatemia is associated with an increased six-year mortality risk in patients on chronic peritoneal dialysis (CPD), data show.
Investigators identified 12,170 CPD patients who underwent PD treatment for at least 90 days in DaVita dialysis clinics from July 2001 to June 2006. Patients were follow-up until June 2007. The researchers divided subjects into eight groups based on serum phosphorus level: less than 3.0, 9.0 or greater, and six groups of 1 mg/dL increments in between.
Compared with a reference value of 5.0-6.0 mg/dL, a phosphorus level greater than 7.0 was associated with increased six-year mortality risk after adjusting for demographics, co-morbid conditions, and surrogates of malnutrition-inflammation complex syndrome, according to a team led by Kamyar Kalantar-Zadeh, MD, PhD, MPH, of the Harold Simmons Center, Harbor-UCLA Medical Center, Torrance, Calif. Subjects with a phosphorus level of 7.0 and above but less than 8.0 had a 30% increased death risk.
Patients with levels of 8.0 and above but less than 9.0 and subjects with levels of 9.0 or higher had a 60% increased risk, the researchers reported. Lower baseline phosphorus levels (below 5.0) appeared protective, the investigators noted. Patients with serum phosphorus levels of 4.0 and higher but less than 5.0, those with levels of 3.0 and above but less than 4.0, and subjects with levels below 3.0 were at 21%, 22%, and 19% decreased risk of death, respectively.