Association of Abnormal Serum Potassium Levels with Arrhythmias and Cardiovascular Mortality: a Systematic Review and Meta-Analysis of Observational Studies

Cardiovasc Drugs Ther. 2018 Apr;32(2):197-212. doi: 10.1007/s10557-018-6783-0.

Abstract

Purpose: To provide the first systematic review and meta-analysis of observational studies on the association of abnormal serum potassium and cardiovascular outcomes.

Methods: Medline and ISI Web of Knowledge were systematically searched from inception until November 24, 2017. Data synthesis of relevant studies was performed using random effects model meta-analyses.

Results: Meta-analyses included 310,825 participants from 24 studies. In the older general population, low serum potassium was associated with a 1.6-fold increased risk of supraventricular arrhythmias (risk ratio [95% confidence interval] 1.62 [1.02-2.55]). Contrarily, high serum potassium was associated with increased cardiovascular mortality (CVM) (1.38 [1.14-1.66]). In patients with acute myocardial infarction, the risk of ventricular arrhythmias was increased for high serum potassium (2.33 [1.60-3.38]). A U-shaped association was observed with a composite cardiovascular outcome in hypertensive patients (2.6-fold increased risk with hypokalemia and 1.7-fold increased risk with hyperkalemia), with CVM in dialysis patients (1.1-fold increased risk with hypokalemia and 1.4-fold increased risk with hyperkalemia) and with CVM in heart failure patients (albeit not statistically significant). Further, only hyperkalemia was associated with an increased risk of a composite cardiovascular outcome in both dialysis (1.12 [1.03-1.23]) and chronic kidney disease (1.34 [1.06-1.71]) patients.

Conclusions: Controlled clinical trials are needed to determine which populations may profit from more frequent potassium-monitoring and subsequent interventions, e.g., change or withdrawal of potassium-influencing drugs, in order to restore normal values and prevent cardiovascular outcomes.

Registration details: Registration in PROSPERO (Centre for Reviews and Dissemination University of York, York, UK): CRD42016048897 ( https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=48897 ).

Keywords: Arrhythmia; Cardiovascular mortality; Meta-analysis; Observational studies; Serum potassium; Systematic review.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Arrhythmias, Cardiac / blood*
  • Arrhythmias, Cardiac / diagnosis
  • Arrhythmias, Cardiac / mortality*
  • Biomarkers / blood
  • Cause of Death
  • Humans
  • Hyperkalemia / blood*
  • Hyperkalemia / diagnosis
  • Hyperkalemia / mortality*
  • Hypokalemia / blood*
  • Hypokalemia / diagnosis
  • Hypokalemia / mortality*
  • Observational Studies as Topic
  • Potassium / blood*
  • Risk Assessment
  • Risk Factors

Substances

  • Biomarkers
  • Potassium