Phosphorus and mortality risk in end-stage renal disease: A meta-analysis

Studies on the association of abnormal serum phosphorus level with all-cause mortality in patients with end-stage renal disease (ESRD) have yielded inconsistent results.

To evaluate the association of abnormal serum phosphorus level with all-cause mortality in patients with ESRD requiring dialysis by conducting a meta-analysis.

Pubmed and Embase databases were searched through March 2017 to identify all observational studies that assessed the association between abnormal serum phosphorus level and all-cause mortality risk in patients with ESRD requiring dialysis. Pooled hazard risk (HR) with 95% confidence interval (CI) was calculated for the highest versus referent phosphorus category and lower versus referent phosphorus category, separately.

Nine cohort studies were eligible for analysis. During 12 to 97.6months follow-up duration, 24,463 death events occurred among 1,992,869 ESRD patients. Meta-analysis showed that the pooled HR of all-cause mortality was 1.16 (95% CI 1.06-1.28) for the lower versus referent serum phosphorus category. Similarly, patients with highest serum phosphorus levels were associated with an increased risk of all-cause mortality (HR 1.39; 95% CI 1.31-1.47) compared with those in the referent phosphorus category. Subgroup analyses revealed that the effect of phosphorus on the all-cause mortality risk appeared to be stronger within 2years follow-up.

Both very high and very low values of phosphorus are independently associated with an increased risk for all-cause mortality in ESRD patients requiring dialysis. This meta-analysis highlighted a non-linear association of serum phosphorus with all-cause mortality among dialysis-dependent ESRD patients.