Kidney Week

Abstract: TH-PO1106

Associations between Serum Potassium and Clinical Outcomes in Patients with CKD in a Real World Setting

Session Information

• Fluid, Electrolyte, Acid-Base Disorders
  November 02, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Fluid, Electrolytes, and Acid-Base

• 704 Fluid, Electrolyte, Acid-Base Disorders

Authors

• McEwan, Philip, Swansea Centre for Health Economics, Swansea University, Singleton Park, United Kingdom

Philip McEwan,

• Qin, Lei, Health Economics and Outcomes Research, AstraZeneca, Gaithersburg, Maryland, United States

Lei Qin,

• Evans, Marc Lyndon, Department of Medicine, University Hospital Llandough, Cardiff, United Kingdom

Marc Lyndon Evans,

• Horne, Laura, Global Medical Affairs, AstraZeneca, Gaithersburg, Maryland, United States

Laura Horne,

• Palaka, Eirini, Health Economics and Outcomes Research, AstraZeneca, Cambridge, United Kingdom

Eirini Palaka,

• Grandy, Susan, Health Economics and Outcomes Research, AstraZeneca, Gaithersburg, Maryland, United States

Susan Grandy,

Background

The associations between serum potassium (K⁺) and rates of mortality and serum K+ and rates of major adverse cardiovascular events (MACE) have previously been characterised using US healthcare data. This study assessed the generalisability of this finding and developed risk equations using UK real-world data on a cohort of chronic kidney disease (CKD) patients.

Methods

A retrospective observational study was conducted using the Clinical Practice Research Datalink from Jan 2006 to Dec 2015. Patients (≥18 years) with a first diagnosis of CKD stage 3 or higher during the study period were analysed with clinical outcomes of interest included all-cause mortality and MACE (arrhythmia, heart failure, myocardial infarction, stroke). Incidence rate ratios (IRRs) associated with time-updated serum K⁺ were estimated using Generalized Estimating Equations adjusted for a broad range of demographic and clinical covariates.

Results

Analysis included 144,388 CKD patients with a mean follow-up of 4.9 years. Patients were predominantly female (60.4%) with a mean age of 73.7 years and mean eGFR of 49.7 mL/min/1.73m². Baseline ischemic heart disease, stroke, myocardial infarction and peripheral vascular disease were present in 11.5%, 6.6%, 3.4% and 2.6% of patients, respectively. There were 34,602 deaths and 71,607 MACE during the study period. U-shaped associations were observed between serum K⁺ and IRRs for mortality and MACE (Figure), with low (<4.5 mEq/L) and high (≥5.5 mEq/L) K⁺ concentrations being positively associated with incidence.

Conclusion

A real-world analysis of UK patients with CKD indicated associations between hypo- and hyperkalemia with risk of mortality and MACE. The observed U-shaped trends were consistent with previously reported US real-world studies.

Funding

• Commercial Support –