The Association Between the Levels of Serum Phosphate and Mortality Rates in Pre-Dialysis and Dialysis Patients

Discovering predictors to reduce morbidity and mortality in chronic kidney disease (CKD) is now a critical global priority. Serum phosphate level is considered to be a potential marker for mortality rate in patients with CKD. Previous studies examined the independent pathogenic role of phosphorus in the development of CKD and dialysis patients but have yielded contradictory findings. This study aims at evaluating the relationship between serum phosphate levels and death rates in pre-dialysis CKD and maintenance of dialysis patients.

PubMed, Scopus, and Web of Science were searched by using MeSH term keywords. The authors did screening, data extraction, and quality assessment in accordance with the inclusion criteria. STATA 14.2 was used for statistical analyses. The analysis was performed using the random- and fixed-effects model when the heterogeneity was >50% and ≤50%, respectively. For evaluating publication bias, Funnel plots and Egger tests were used.

Eleven original studies between 2005 and 2021 met the eligibility criteria. The overall estimate of unadjusted HR of all-cause mortality each 1 mg/dL increase in the serum phosphate concentration using the random-effects model in pre-dialysis CKD and dialysis patients was 1.33 (95% CI: 0.97, 1.82, I² = 99.1%, P = 0.074), and for adjustment, Hazard ratio was 1.27 (95% CI: 1.15, 1.39, I² = 75.4%, P < 0.001).

The findings showed the association between serum phosphate levels and death rates in pre-dialysis individuals with CKD and dialysis patients.