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Cardiovascular Drugs and Therapy
Published in: Cardiovascular Drugs and Therapy 2/2018

01-04-2018 | REVIEW ARTICLE

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

Authors: Liesa K. Hoppe, Dana C. Muhlack, Wolfgang Koenig, Prudence R. Carr, Hermann Brenner, Ben Schöttker

Published in: Cardiovascular Drugs and Therapy | Issue 2/2018

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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).
Appendix
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Metadata
Title
Association of Abnormal Serum Potassium Levels with Arrhythmias and Cardiovascular Mortality: a Systematic Review and Meta-Analysis of Observational Studies
Authors
Liesa K. Hoppe
Dana C. Muhlack
Wolfgang Koenig
Prudence R. Carr
Hermann Brenner
Ben Schöttker
Publication date
01-04-2018
Publisher
Springer US
Published in
Cardiovascular Drugs and Therapy / Issue 2/2018
Print ISSN: 0920-3206
Electronic ISSN: 1573-7241
DOI
https://doi.org/10.1007/s10557-018-6783-0

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