Long-term treatment with oral
torsemide was studied to determine its effectiveness in maintaining steady-state fluid balance in patients with
chronic renal insufficiency by using a placebo-controlled, double-blind, random-off design. Patients with stable
chronic renal insufficiency were initially titrated and then stabilized on
torsemide. Once stabilized on
torsemide, patients were randomly assigned in a double-blind fashion to continue on their titrated dose of
torsemide or to receive a placebo. Of the 82 patients enrolled in the study, 68 were randomized to
torsemide (n = 34) or placebo (n = 34). Patients who received the placebo showed a significantly greater (p < 0.001) mean increase in
body weight (3.55 lb) than did patients who remained on
torsemide (0.46 lb). Approximately two-thirds of the
weight gain observed in the placebo group occurred during the first 3 days after randomization. Patients continued to receive treatment unless they developed fluid accumulation that was considered deleterious to their clinical state as determined by the investigator. In the placebo group a greater number of patients discontinued treatment because of
weight gain or fluid accumulation. The mean number of days on treatment after randomization was significantly higher (p < 0.001) for patients who received
torsemide (26 days) than for patients who received the placebo (16 days). The lack of
weight gain in the
torsemide group was associated with a higher percentage of patients who showed no change or an improvement in peripheral
edema status (79%) than in placebo patients (35%). No patient was withdrawn from the study because of
hyperkalemia or
hypokalemia. The adverse effects reported during the study were as anticipated for patients with
chronic renal insufficiency that is often complicated by other underlying illnesses.