Introduction: Hyperaldosteronism (HA) is a common cause of secondary hypertension and may contribute to resistant hypertension (RH). The authors sought to determine and characterize HA screening, positivity rates, and mineralocorticoid receptor antagonist (MRA) use among patients with RH.
Methods: A cross-sectional study was performed within Kaiser Permanente Southern California (7/1/2012-6/30/2017). Using contemporary criteria, RH was defined as blood pressure uncontrolled (≥ 130/80) on ≥ 3 medications or requiring ≥ 4 antihypertensive medications. The primary outcome was screening rate for HA defined as any aldosterone and plasma renin activity measurement. Secondary outcomes were HA screen positive rates and MRA use among all patients with RH. Multivariable logistic regression analysis was used to estimate odds ratio (with 95% confidence intervals) for factors associated with HA screening and for patients that screened positive.
Results: Among 102,480 patients identified as RH, 1977 (1.9%) were screened for HA and 727 (36.8%) screened positive for HA. MRA use was 6.5% among all patients with RH (22.5% among screened, 31.2% among screened positive). Black race, potassium < 4, bicarbonate > 29, chronic kidney disease, obstructive sleep apnea, and systolic blood pressure were associated with HA screening, but only Black race (1.55 [1.20-2.01]), potassium (1.82 [1.48-2.24]), bicarbonate levels (1.39 [1.10-1.75]), and diastolic blood pressure (1.15 [1.03-1.29]) were associated with positive screenings.
Conclusion: The authors' findings demonstrate low screening rates for HA among patients with difficult-to-control hypertension yet a high positivity rate among those screened. Factors associated with screening did not always correlate with screening positive. Screening and targeted use of MRA may lead to improved blood pressure control and outcomes among patients with RH.
Keywords: epidemiology; hyperaldosteronism; hypertension; pharmacotherapy; resistant hypertension.