Furosemide Prescription During the Dry State Is a Predictor of Long-Term Survival of Stable, Optimally Medicated Patients With Systolic Heart Failure

Background: Furosemide is associated with poor prognosis in patients with heart failure and reduced ejection fraction (HFrEF). Aim: To evaluate the association between daily furosemide dose prescribed during the dry state and long-term survival in stable, optimally medicated outpatients with HFrEF. Population and Methods: Two hundred sixty-six consecutive outpatients with left ventricular ejection fraction <40%, clinically stable in the dry state and on optimal heart failure therapy, were followed up for 3 years in a heart failure unit. The end point was all-cause death. There were no changes in New York Heart Association class and therapeutics, including diuretics, and no decompensation or hospitalization during 6 months. Furosemide doses were categorized as low or none (0-40 mg/d), intermediate (41-80 mg/d), and high (>80 mg). Cox regression was adjusted for significant confounders. Results: The 3-year mortality rate was 33.8%. Mean dose of furosemide was 57.3 21.4 mg/d. A total of 47.6% of patients received the low dose, 42.1% the intermediate dose, and 2.3% the high dose. Receiver operating characteristics for death associated with furosemide dose showed an area under the curve of 0.74 (95% confidence interval [CI]: 0.68-0.79; P < .001), and the best cutoff was >40 mg/d. An increasing daily dose of furosemide was associated with worse prognosis. Those receiving the intermediate dose (hazard ratio [HR] = 4.1; 95% CI: 2.57-6.64; P < .001) or high dose (HR = 19.8; 95% CI: 7.9-49.6; P < .001) had a higher risk of mortality compared to those receiving a low dose. Patients receiving >40 mg/d, in a propensity score-matched cohort, had a greater risk of mortality than those receiving a low dose (HR = 4.02; 95% CI: 1.8-8.8; P = .001) and those not receiving furosemide (HR = 3.9; 95% CI: 0.07-14.2; P = .039). Conclusion: Furosemide administration during the dry state in stable, optimally medicated outpatients with HFrEF is unfavorably associated with long-term survival. The threshold dose was 40 mg/d.