Prevalence of primary hyperaldosteronism assessed by aldosterone/renin ratio and spironolactone testing.

Recent studies have suggested that primary hyperaldosteronism may be present in more than 10% of patients with hypertension. We aimed to estimate the prevalence in unselected patients in primary care, and investigate the influence of current drug treatment upon the aldosterone/renin ratio (ARR) and its prediction of blood pressure response to spironolactone. We measured blood pressure, plasma electrolytes, renin activity and aldosterone in 846 patients with hypertension.