Relationship between serum phosphorus variation and prognosis in elderly patients with maintenance hemodialysis

Abstract

Objective To investigate the relationship between serum phosphorus variability and prognosis in elderly patients with maintenance hemodialysis (MHD). Methods A total of 121 patients over 60 years treated with MHD from hemodialysis center of Jiangyin people’s hospital were enrolled from October 2010 to June 2016 in this study. According to their median of coefficient of variation (CV) of blood phosphorus, the patients were divided into high variation group (CV≥0.18 mmol/L) and low variation group (CV<0.18 mmol/L). The relationship of serum phosphorus CV with all-cause mortality and cardiovascular disease mortality was assessed respectively. Results Forty patients (33.1%) died for all cause and 17 patients (14.0%) died for cardiovascular disease. Compared with patients in low phosphorus variation group, patients had a higher all-cause in high phosphorus variation group (40.6% vs.20.6%, P=0.002), higher cardiovascular disease mortality was observed in high variation group as well (24.1% vs.4.8%, P=0.003). COX regression analysis showed that high CV of phosphorus (HR=2.442, 95%CI: 1.253-4.760, P=0.009) , low serum creatinine (HR=0.998, 95%CI: 0.996-1.000, P=0.017) and high C-reactive protein were independent risk factors for all-cause mortality. Moreover, high CV of phosphorus (HR=5.244, 95%CI: 1.486-8.507, P=0.010) and low albumin (HR=0.829, 95%CI: 0.711-0.967, P=0.017) were independent risk factors for cardiovascular disease mortality. Kaplan-Meier method showed that patients with high phosphorus variation had higher all-cause and cardiovascular disease mortality than patients with low phosphorus variation(P=0.001). Conclusions The high CV of phosphorus is independently correlated with all-cause and cardiovascular disease mortality in elderly patients with MHD. Key words: Renal Dialysis; Phosphorus; Aged; Prognosis