Correlation between Hyperkalemia and the Duration of Several Hospitalizations in Patients with Chronic Kidney Disease

(1) Background: This observational study aimed to verify the association between serum potassium levels and hospitalization days in patients with chronic kidney disease in a follow up of nine months. (2) Methods: Patients with chronic kidney disease were divided into group A (180 patients, potassium <= 5.1 mEq/L) and B (90 patients, potassium > 5.1 mEq/L). Student's t-test, Mann-Whitney test, Pearson's Chi-Square test, Pearson/Spearman's correlation test and linear regression test were performed in the entire sample and in stage-G4/5 subsample. (3) Results: Groups A and B differed for estimated glomerular filtration rate (eGFR) (34.89 (IQR, 16.24-57.98) vs. 19.8 (IQR, 10.50-32.50) mL/min/1.73 m(2); p < 0.0001), hemoglobin (11.64 +/- 2.20 vs. 10.97 +/- 2.19 g/dL, p = 0.048), sum of hospitalization days (8 (IQR, 6-10) vs. 11 (IQR, 7-15) days; p < 0.0001) and use of angiotensin II receptor blockers (40.2% vs. 53.3%; p = 0.010). Considering patients with eGFR 6-30 mL/min/1.73 m(2), differences in the sum of hospitalization days were confirmed. Multivariable regression analysis showed that hyperkalemia is an independent risk factor of increased hospital length. In stage G4-G5, regression analysis showed that hyperkalemia is the only independent risk factor (beta = 2.93, 95% confidence interval, 0.077-5.794, p = 0.044). (4) Conclusions: We observed significantly greater odds of increased length of hospital stay among patients with higher potassium, mostly in stages G4-G5 chronic kidney disease.

Automated summary

This observational study aimed to verify the association between serum potassium levels and hospitalization days in patients with chronic kidney disease. The results showed that hyperkalemia is an independent risk factor for increased length of hospital stay, particularly in patients with stage G4-G5 chronic kidney disease.