Association of hypophosphatemia during continuous kidney replacement therapy and clinical outcomes: a systematic review and meta-analysis

Introduction: Hypophosphatemia is a common and potentially severe complication of continuous kidney replacement therapy (CKRT), but the evidence on the correlation between hypophosphatemia occurring during CKRT and clinical outcomes remains limited. Methods: Electronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to March 1, 2024. All possible studies that examined the following outcomes were included: all-cause mortality, mechanical ventilation, intensive care unit (ICU) stay, and CKRT duration. Results: A total of 8,631 patients from eight cohort studies were included. There was no statistical association between hypophosphatemia during CKRT and all-cause mortality in critically ill patients (OR 0.82, 95% CI 0.57–1.18, P =0.28, I2 = 83%). However, hypophosphatemia was associated with longer duration of mechanical ventilation (WMD 80.30h, 95% CI 31.37–129.22, P =0.001, I2 = 60%). Furthermore, a longer length of ICU stay (WMD 2.76d, 95% CI 2.50–3.02, P <0.00001, I2 = 36%) and CKRT duration (WMD 51.51h, 95% CI 2.69–100.34, P =0.04, I2 = 96%) were observed in patients with hypophosphatemia. Conclusions: The association between hypophosphatemia and mortality in patients receiving CKRT was insufficient. However, hypophosphatemia during CKRT might be associated with adverse clinical outcomes for critically ill patients.