Approximately 20 percent of elderly patients use long-term diuretic therapy, mainly for heart failure and hypertension. In addition to cost, prolonged use of these agents is associated with the risk of hypokalemia, hyponatremia, dehydration and cardiac arrest. Walma and colleagues investigated the effect of withdrawal of diuretics in healthy elderly patients with stable blood pressures.

From eight Dutch general practices, the authors recruited 202 healthy elderly patients who had taken diuretics for at least six months and in whom no heart failure or current elevations of blood pressure were present. The patients were assessed at home on two occasions and were then randomly assigned to placebo (withdrawal group) or continuation of diuretic treatment (control group). The randomization was stratified by age and type of diuretic to ensure comparability between the groups. Patients were visited at home by physicians at two days, at one week and at two weeks. Further follow-up was performed at one, three and six months. At each visit, possible symptoms of heart failure were assessed using standardized scoring scales, and blood pressure levels were measured under standardized conditions. Compliance was verified by tablet counts and patient interview at every visit and by assessment of serum diuretic concentrations at the beginning and end of the study.

In the first six months, 25 patients in the withdrawal group and four in the control group developed heart failure symptoms of sufficient severity to merit diuretic therapy. In addition, 25 withdrawal patients and nine control patients met criteria for diuretic therapy for other indications. Mean blood pressure elevations in the withdrawal group were 13.5 mm Hg systolic and 4.6 mm Hg diastolic. The need for diuretic therapy was more marked in women but did not appear to be related to any other patient variable. Most patients developed symptoms within four weeks of withdrawal. No patients suffered serious adverse effects or required hospital admission.

The authors conclude that withdrawing elderly patients from long-term diuretic therapy resulted in symptoms of heart failure and/or increased blood pressure in most cases and that approximately one half of such patients should restart diuretic therapy. The authors caution that any attempt to withdraw established diuretic therapy in the elderly must be done under careful monitoring, especially during the first four weeks, and should be restricted to patients with hypertension and noncardiac edema.