SAN DIEGO—Phosphate level is a stronger predictor for increased mortality among hemodialysis (HD) patients than calcium and parathyroid hormone (PTH) levels, and should be the priority for control, according to the findings of a Japanese study presented at Kidney Week 2012.
Masatomo Taniguchi, MD, of the Graduate School of Medical Sciences at Kyushu University in Fukuoka, and colleagues examined the associations between annual values of phosphorus, calcium, and parathyroid hormone (PTH) and mortality in a cohort of 128,125 HD patients. They also examined associations between Japanese guideline targets of 3.5-6.0 mg/dL for phosphate, 8.4-10 mg/dL for calcium, and 60-180 pg/mL for PTH and all-cause mortality.
High and low serum phosphate (greater than 6.0 and 3.5 mg/dL or lower), high calcium (greater than 9.5 mg/dL), and higher and lower PTH (greater than 300 and less than 60 pg/mL) were significantly associated with higher mortality. Hyperphosphatemia was associated with a significantly greater mortality than abnormal levels of calcium and PTH.
Patients who achieved target values for all parameters simultaneously had the lowest mortality. Those who met only the phosphate target had a 17% increased risk of death, whereas patients who achieved on calcium or PTH targets had a 41% and 47% increased risk, respectively.