Effect of spironolactone in resistant arterial hypertension

Abstract

This study was designed to assess the effect of the addition of low-dose spironolactone on blood pressure (BP) in patients with resistant arterial hypertension. Patients with office systolic blood pressure (SBP) >140mm Hg or diastolic blood pressure (DBP)>90mmHg despite treatment with at least 3 antihypertensive drugs, including a diuretic, were enrolled in this double-blind, placebo-controlled, multicentre trial. One hundred sixtyone patients in outpatient internal medicine departments of 6 hospitals in the Czech Republic were randomly assigned to receive 25mg of spironolactone (N=81) or a placebo (N=80) once daily as an add-on to their antihypertensivemedication, using simple randomization. This study was registered with ClinicalTrials.gov, number NCT00524615. Analyses were done with 150 patients who finished the follow-up (74 in the spironolactone and 76 in the placebo group). At 8 weeks, BP values were decreased more by spironolactone, with differences in mean fall of SBP of-9.8, -13.0, -10.5, and -9.9mm Hg (P<0.001 for all) in daytime, nighttime, and 24-hour ambulatory BP monitoring and in the office. The respective DBP differences were -3.2, -6.4,-3.5, and -3.0mm Hg (P=0.013, P<0.001, P=0.005, and P=0.003). Adverse events in both groups were comparable. The office SBP goal <140mm Hg at 8 weeks was reached in 73% of patients using spironolactone and 41% using placebo (P=0.001). Spironolactone in patients with resistant arterial hypertension leads to a significant decrease of both SBP and DBP and markedly improves BP control.