Aldosterone Antagonists or Renin-Guided Therapy for Treatment-Resistant Hypertension: A Comparative Effectiveness Pilot Study in Primary Care

BACKGROUND: Uncontrolled treatment-resistant hypertension (TRH), i.e., blood pressure (BP, mm Hg) ≥140/≥90mm Hg in and out of office on ≥3 different BP medications at optimal doses, is common and has a poor prognosis. Aldosterone antagonist (AA) and renin-guided therapy (RGT) are effective strategies for improving BP control in TRH but have not been compared. METHODS: A comparative effectiveness TRH pilot study of AA vs. RGT was conducted in 4 primary care clinics with 2 each randomized to AA or RGT. The primary outcome was change in clinic BP defined by means of 5 automated office BP values. Eighty-nine patients with apparent TRH were screened and 44 met criteria for true TRH. RESULTS: Baseline characteristics of 20 patients in the AA (70% Black, 45% female, mean age: 57.4 years) and 24 patients in RGT (79% Black, 50% female, 57.8 years) arms were similar with baseline BP 162±5/90±3 vs. 153±3/84±3, respectively, P = 0.11/0.20. BP declined to 144±5/86±4 in AA vs. 132±4/75±3 in RGT, P = 0.07/0.01; BP was controlled to JNC7 (Seventh Joint National Committee Report) goal in 25% vs. 62.5%, respectively, P < 0.01. Although BP changes from baseline, the primary outcome, were not different (-17.6±5.1/-4.0±3.0 AA vs. -20.4±3.8/-9.7±2.0 RGT, P = 0.65/0.10.), more BP medications were added with AA than RGT (+0.9±0.1 vs. +0.4±0.1 per patient, P < 0.01). CONCLUSIONS: In this TRH pilot study, AA and RGT lowered BP similarly, although fewer additional medications were required with RGT. A larger comparative effectiveness study could establish the utility of these treatment strategies for lowering BP of uncontrolled TRH patients in primary care.