Heart failure: 40% patients develop hyperkalaemia

Takeaway

• 39% of patients with congestive heart failure (CHF) develop hyperkalaemia and many have recurrent episodes.
• Reduced kidney function and use of spironolactone show significant association with risk for hyperkalaemia.
• Hyperkalaemia was associated with 2.75 times higher risk for acute hospitalisation and more than 3-fold increased risk for mortality.

Why this matters

• Findings call for regular monitoring of potassium levels in patients with CHF.

Study design

• Danish population-based cohort study of 31,649 patients with incident CHF.
• Funding: AstraZeneca; Lundbeck Foundation and the Novo Nordisk Foundation.

Key results

• 39% of patients experienced hyperkalaemia during mean follow-up of 2.2 years.
• Risks for second, third or fourth events were 43%, 54% and 60%, respectively.
• Within 1 year, 26%, 35%, 44% and 48% patients with stage IIIA, IIIB, IV or V kidney dysfunction, respectively, experienced hyperkalaemia.
• Chronic kidney disease (prevalence ratio, 1.46; 95% CI, 1.43-1.49), diabetes mellitus (prevalence ratio, 1.38; 95% CI, 1.32-1.45) and spironolactone use (prevalence ratio, 1.48; 95% CI, 1.42-1.54) were significant risk factors for hyperkalaemia.
• At 6 months after hyperkalaemia event, acute-care hospitalisation was 74% vs 53% at 6 months before the event (risk ratio, 1.41; 95% CI, 1.38-1.44).
• In patients with hyperkalaemia, 6-month risk for acute-care hospitalisation (aHR, 2.75; 95% CI, 2.65-2.85) and mortality (aHR, 3.39; 95% CI, 3.19-3.61) was higher vs those without.

Limitations

• Observational design.