Objective:

To evaluate the prognostic roles of glycemic variability and calcium-phosphate metabolic disorders in critically ill elderly patients with chronic kidney disease.

Approach:

• Study Design: This retrospective observational cohort study utilized three cohorts: MIMIC-IV (n = 1,319), multicenter eICU (n = 996), and Chinese hospital cohort (n = 1,069).
• Statistical Analysis: Multivariable Cox regression and meta-analysis were employed to assess the associations between variables.

Key Findings:

• Elevated glucose variability independently predicted 28- and 90-day mortality, with predominant early risk.
• Concurrent hypocalcemia and hyperphosphatemia indicated the poorest prognosis.
• High glucose variability produced synergistic harmful effects in patients with mineral imbalances.

Interpretation:

Targeted management of glycemic variability and correction of calcium-phosphate homeostasis may improve survival in this population.

Limitations:

• The retrospective design may introduce selection and information bias.
• Findings may not be generalizable to all critically ill populations due to cohort characteristics.

Conclusion:

The study highlights the importance of considering both glucose variability and mineral imbalances in predicting outcomes for critically ill elderly patients with CKD.