Abstract: PO1446
Serum Potassium Levels at Hospital Discharge and 1-Year Mortality Among Hospitalized Patients
Session Information
- Fluid, Electrolyte, and Acid-Base Disorders: Clinical - 1
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Fluid, Electrolyte, and Acid-Base Disorders
- 902 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Mao, Michael A., Mayo Clinic's Campus in Florida, Jacksonville, Florida, United States
- Thongprayoon, Charat, Mayo Clinic Minnesota, Rochester, Minnesota, United States
- Cheungpasitporn, Wisit, Mayo Clinic Minnesota, Rochester, Minnesota, United States
- Thirunavukkarasu, Sorkko, Mayo Clinic Minnesota, Rochester, Minnesota, United States
- Chewcharat, Api, Mayo Clinic Minnesota, Rochester, Minnesota, United States
- Erickson, Stephen B., Mayo Clinic Minnesota, Rochester, Minnesota, United States
Background
The aim was to assess the relationship between discharge serum potassium levels and one-year mortality in hospitalized patients.
Methods
All adult hospital survivors between years 2011 and 2013 at a tertiary referral hospital who had available admission and discharge serum potassium levels were enrolled. End-stage kidney disease patients were excluded. Discharge potassium was defined as the last potassium measured within 48 hours prior to hospital discharge and categorized into ≤2.9, 3.0-3.4, 3.5-3.9, 4.0-4.4, 4.5-4.9, 5.0-5.4 and ≥5.5 mEq/L. Cox proportional hazard analysis was performed to assess the independent association between discharge potassium and one-year mortality after hospital discharge, using discharge potassium of 4.0-4.4 mEq/L as the reference group.
Results
Of 57,874 eligible patients, with a mean discharge serum potassium of 4.1±0.4 mEq/L, the estimated one-year mortality rate after discharge was 13.2%. A U-shaped association was observed between discharge potassium and one-year mortality, with nadir mortality in the discharge potassium of 4.0-4.4 mEq/L. After adjustment for clinical characteristics, including admission potassium, both discharge potassium of ≤3.9 mEq/L and ≥4.5 mEq/L were significantly associated with increased one-year mortality, compared with the discharge potassium of 4.0-4.4 mEq/L. Stratified analysis based on admission serum potassium showed similar results except that there was no increased risk of one-year mortality if discharge potassium group was ≤3.9 mEq/L in patients with an admission potassium of ≥5.0 mEq/L.
Conclusion
The association between discharge serum potassium and one-year mortality after hospital discharge had a U-shaped distribution and was independent of admission potassium. Favorable survival outcomes occurred when discharge potassium was within the range of 4.0-4.4 mEq/L.
The Kaplan-Meier plot of one-year mortality based on discharge serum potassium levels