ATLANTA—Researchers who studied a group of chronic kidney disease (CKD) patients who were mostly African American found that serum phosphorus levels were not associated with mortality or dialysis initiation, according to a report presented at the American Society of Nephrology’s Kidney Week 2013.
Previous studies have shown that serum phosphorus levels, even within the normal range are associated with adverse outcomes in CKD populations, the researchers observed. They noted, however, that subjects in previous studies were mainly white, and racial differences have not been previously examined despite differences in vitamin D and parathyroid hormone homeostasis in African Americans.
Shailesh Basani, MD, of Indiana University in Indianapolis, and colleagues studied 996 CKD patients visiting a nephrology clinic at a large urban county hospital from 2007-2010. Of these, 60% were African American. The study population had a mean age of 58.5 years and mean estimated glomerular filtration rate (eGFR) of 33.4 mL/min/1.73 m2. The median phosphate level was 3.8 mg/dL.
During a median follow-up of 1,125 days, 331 patients (33.2%) either died or initiated dialysis. In multivariate analysis, serum phosphorus levels were not a significant factor in predicting mortality or dialysis initiation. The findings raise questions “on the generalizability of previous research studies to the clinic setting,” the authors concluded.