Examining the “repletion reflex”: The association between serum potassium and outcomes in hospitalized patients with heart failure

Kevin F. O’Sullivan, Mohammad Amin Kashef, Alexander B. Knee, Alexander S. Roseman, Penelope S. Pekow, Mihaela S. Stefan, Meng Shiou Shieh, Quinn R. Pack, Peter K. Lindenauer, Tara Lagu*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

BACKGROUND: In patients hospitalized with heart failure (HF) exacerbations, physicians routinely supplement potassium to maintain levels ≥4.0 mEq/L. The evidence basis for this practice is relatively weak. We aimed to evaluate the association between serum potassium levels and outcomes in patients hospitalized with HF. METHODS: We identified patients admitted with acute HF exacerbations to hospitals that contributed to an electronic health record-derived dataset. In a subset of patients with normal admission serum potassium (3.5-5.0 mEq/L), we averaged serum potassium values during a 72-hour exposure window and categorized as follows: <4.0 mEq/L (low normal), 4.0-4.5 mEq/L (medium normal), and >4.5 mEq/L (high normal). We created multivariable models examining associations between these categories and outcomes. RESULTS: We included 4,995 patients: 2,080 (41.6%), 2,326 (46.6%), and 589 (11.8%) in the <4.0, 4.0-4.5, and >4.5 mEq/L cohorts, respectively. After adjustment for demographics, comorbidities, and presenting severity, we observed no difference in outcomes between the low and medium normal groups. Compared to patients with levels <4.0 mEq/L, patients with a potassium level of >4.5 mEq/L had a longer length of stay (median of 0.6 days; 95% CI: 0.1 to 1.0) but did not have statistically significant increases in mortality (OR [odds ratio] = 1.51; 95% CI: 0.97 to 2.36) or transfers to the intensive care unit (OR = 1.78; 95% CI: 0.98 to 3.26). CONCLUSIONS: Inpatients with heart failure who had mean serum potassium levels of <4.0 showed similar outcomes to those with mean serum potassium values of 4.0-4.5. Compared with mean serum potassium level of <4.0, mean serum levels of >4.5 may be associated with increased risk of poor outcomes.

Original languageEnglish (US)
Pages (from-to)729-736
Number of pages8
JournalJournal of hospital medicine
Volume14
Issue number12
DOIs
StatePublished - 2019
Externally publishedYes

ASJC Scopus subject areas

  • Internal Medicine
  • Leadership and Management
  • Fundamentals and skills
  • Health Policy
  • Care Planning
  • Assessment and Diagnosis

Fingerprint

Dive into the research topics of 'Examining the “repletion reflex”: The association between serum potassium and outcomes in hospitalized patients with heart failure'. Together they form a unique fingerprint.

Cite this