Comparison of frequency of occurrence of hypokalaemia with torsemide versus furosemide in patients with chronic heart failure: randomized prospective study

Abstract

Aim of the study

Loop diuretics are commonly used in heart failure to provide symptomatic relief. Furosemide and Torsemide are the most commonly prescribed loop diuretics for this condition. Although torsemide has been proven to be superior to furosemide in terms of efficacy, evidence is lacking regarding its safety in terms of frequency of occurrence of hypokalaemia.

Materials and Methods

This open label parallel group study was conducted considering 100 patients with chronic heart failure randomized into two groups to receive either oral torsemide 10 mg OD (Group T: n=50) or oral furosemide 20 mg BD (Group F: n=50). Baseline serum levels of Na⁺, K⁺ and Cl^- and ejection fraction (EF) were recorded and the study drugs were administered. Patients were followed up at 4, 8 and 12 weeks and at each visit, serum Na⁺, K⁺, Cl^-, and EF were noted.

Results

All the study participants completed the study and data was analyzed using per protocol analysis. Baseline characteristics were comparable between the groups in terms of age, gender, baseline serum electrolyte levels and ejection fraction. There was significant decrease in serum electrolyte levels in both the groups at each follow up. However, potassium levels in torsemide group was significantly greater as compared to furosemide group at 12 weeks (p=0.001). There was significant improvement in EF at each follow up in both the groups. However, there was no significant difference between the groups. The number of patients with reduced EF decreased over each visit. No adverse reaction related to the study drugs were reported for the entire study period.

Conclusion

Oral torsemide 10 mg OD is safer than oral furosemide 20 mg BD in reducing the frequency of occurrence of hypokalaemia in patients with chronic heart failure.