Do fixed dose combinations of a thiazide and potassium sparing diuretic reduce the prevalence of hypokalaemia compared to thiazide alone in elderly patients?
Fixed-dose combinations of thiazide and potassium-sparing diuretics may not effectively prevent hypokalemia and can increase the risk of hyponatremia in elderly patients, questioning their widespread use over single agents.
Plasma potassium and sodium concentrations were measured in a group of elderly patients taking maintenance thiazide diuretic therapy alone, with a potassium supplement or in combination with a potassium sparing diuretic. Fixed dose combinations of a thiazide and potassium sparing diuretic did not significantly reduce the prevalence of hypokalaemia and the combination of amiloride-hydrochlorothiazide was associated with a disproportionate number of cases of hyponatraemia. The desirability of the current widespread use of fixed dose combination diuretics over less expensive single agents is questioned.
Kingma et al. (Wed,) studied this question.