Graham Colm
LAS VEGAS—New research suggests a link between serum phosphorous levels and anemia in patients without chronic kidney disease (CKD).
Previous studies have shown that elevations in serum phosphorous are associated with anemia in patients with end-stage renal disease, but whether the link exists in patients without CKD has been unclear.
Now, results of a large study indicate that patients without CKD who have elevated serum phosphorus also have an increased risk of anemia.
John J. Sim, MD, of the Kaiser Permanente Los Angeles Medical Center, and his colleagues presented these findings at the National Kidney Foundation’s 2014 Spring Clinical Meetings (abstract 1708).
The researchers evaluated 32,907 patients with documented serum phosphorus levels, hemoglobin values, and estimated glomerular filtration rates of 60 mL/min or greater. Anemia was defined as having a hemoglobin level below 11 g/dL.
The mean age was 52 years, and 62% of patients were female. The majority of patients were classified as white, 26% as Hispanic, 15% as black, and 7% as Asian.
Serum phosphorus levels ranged from 1.9 mg/dL to 5.7 mg/dL. And 13% of subjects met the criteria for anemia.
Multivariable analysis revealed that each 0.5 mg/dL increase in serum phosphorus level was associated with a 7% increase in the risk of anemia.
The researchers also divided subjects into quartiles according to serum phosphorous levels and calculated the odds ratios (ORs) for anemia.
For the 3.1 mg/dL to 3.5 mg/dL quartile, the OR was 0.85. For the 3.5 mg/dL to 3.9 mg/dL quartile, the OR was 0.90. And for the 3.9 mg/dL to 5.7 mg/dL quartile, the OR was 1.05.
The researchers noted that the link was “more pronounced” in men, but the results suggest that elevated serum phosphorous levels are associated with anemia in non-CKD patients of both sexes.
