Potassium balance in heart failure is affected by many factors including neurohormonal mechanisms and drugs used in its management. Renin–angiotensin–aldosterone system inhibitor therapies are part of heart failure therapy and have been associated with increase the risk of hyperkalemia. Currently, there are limited data on the prevalence and risk factors of hyperkalemia in heart failure patients who received spironolactone as an add-on to standard therapy which include Angiotensin-Converting Enzyme Inhibitors (ACEIs) or Angiotensin II receptor blockers (ARBs). The objective of this study is to identify Incidence and determine of hyperkalemia risk factors among heart failure patients who have been using spironolactone.
This is a retrospective chart review, from March 1, 2016 to March 31, 2019 conducted at King Abdulaziz Medical City-Riyadh. All heart failure patients with age more than 18 year who are using spironolactone were included and we excluded if they had any of the following criteria: (1) end stage renal disease on dialysis; (2) cancer; (3) history of hyperkalemia. A data collection sheet was used to collect demographics (e.g., age, gender, weight, ejection fraction, and baseline potassium), comorbidities (e.g., chronic kidney disease, and diabetes), visit history (dose of spironolactone, hyperkalemia incidence, time to the event, medication that was patient on include (ACEI, ARB, digoxin, furosemide, beta-blockers, and potassium supplements), average potassium level, average creatinine, and average BNP). An Excel-based tool (Microsoft® Excel; Version 2018) was used for systematic data sampling and analysis. The study was approved by Institutional Review Board.
A total of 349 patients met the inclusion criteria. 43% of patients were men while 57% were women. The mean age of patients was 64.87 ± 14.02 years. The mean baseline of potassium before start spironolactone were 4.34 ± 3.45 mmol/L. Hyperkalemia were assessed with different dose of spironolactone (12.5 mg, 25 mg, 50 mg). 161 patients were received 12.5 mg spironolactone, 40% of those patients who had incidence of hyperkalemia. 62% of those who developed hyperkalemia were on ACEI, 28% on ARB, 14% on potassium supplements. 263 patients were received 25 mg spironolactone, 47% of patients had incidence of hyperkalemia. 49% of those who developed hyperkalemia were on ACEI, 31% on ARB, and 22% on potassium supplements. 17 patients were received 50 mg spironolactone, 53% of patients had incidence of hyperkalemia. 44% of those who developed hyperkalemia were on ACEI, 22% on ARB, and 22% on potassium supplements.
Our study showed that half of heart failure patients who used spironolactone developed hyperkalemia. The majority of patients who developed hyperkalemia were either on ACEIs or ARBs. Spironolactone dosing of 50 mg was associated with highest incidence of hyperkalemia. Further study with a larger sample size is required to clarify and confirm our study findings.