Resistant hypertension and undiagnosed primary hyperaldosteronism detected by use of a computerized database.

A pharmacy database was used to identify patients with resistant hypertension who could then be tested for the presence of primary hyperaldosteronism. Inclusion criteria were: (1) resistant hypertension defined as uncontrolled hypertension and use of 3 antihypertensive medication classes or ≥ 4 antihypertensive classes regardless of blood pressure; (2) low or normal potassium levels (≤ 4.9 mEq/L); and (3) continuous health care from October 1, 2008, to February 28, 2009. Exclusion criteria were: (1) past or current use of an aldosterone antagonist, or (2) a medication possession ratio (adherence) <80% for any antihypertensive drug. Hyperaldosteronism was classified as an aldosterone/renin ratio (ARR) ≥ 30. Using the computer, 746 patients were identified who met criteria. After manual chart review to verify inclusion and exclusion criteria, 333 patients remained. Of 184 individuals in whom an ARR was obtained, 39 (21.2%) had a ratio of ≥ 30. A computer database is useful to identify patients with resistant hypertension and those who may have primary aldosteronism.