PP.26.08

Abstract

Objective: No consensus has been established which is the best fourth-line agent in patients with RHT. We previously demonstrated that bioimpedance-guided reduction of extracellular volumen with intensification of diuretic therapy can control BP in patients with RHT. To assess the effect of intensifying diuretic treatment with a loop diuretic (furosemide) or an aldosterone antagonist (spironolactone) on control of BP in patients with RHT. Design and method: Study population comprised 30 patients with RHT (mean of 4.1 ± 0.9 antihypertensive drugs/patient) who were divided into 2 treatment arms according to clinical criteria. Fifteen patients received furosemide 40 mg/day and 15 patients spironolactone 25 mg/day in combination with habitual medication. Ambulatory BP monitoring was performed baseline, 3 months, and 6 months. Results: Baseline BP was 162 ± 8/90 ± 6 mmHg, 70%men, age 63.3 ± 9.1 years, and 56.1% diabetic. Baseline glomerular filtration rate (eGFR-CKD-EPI) was 55.8 ± 16.5 mL/min/1.73m2. No significant differences were found between groups at baseline in age, gender, % diabetics, eGFR, BP, number of antihypertensive drugs, or aldosterone levels. At 6 months, systolic BP decreased 24 ± 9.2 mmHg (from 163.6 ± 8.6 to 139.6 ± 8.1 mmHg) in spironolactone group, compared with 13.8 ± 2.8 mmHg (from 162 ± 7.9 to 148 ± 6.4 mmHg) in furosemide group(p < 0.01). Diastolic BP fell 11 ± 8.1 mmHg in spironolactone group compared with 5.2 ± 2.2 mmHg in furosemide group (p < 0.01). Forty percent of patients in spironolactone group reached the BP target (<140/90 mmHg) at 6 months compared with only 13% in furosemide arm. No significant changes in eGFR in any group during follow up. A significant reduction in urinary albumin creatinine ratio (from 173 ± 268 to 14 ± 24 mg/g, p < 0.01) was observed in spironolactone group at 6 months, but not in furosemide group. Multiple regression analysis showed that only treatment with spironolactone was associated with control of BP < 140/90 mmHg at 6 months. No severe adverse events were recorded. Mild hyperkalemia was observed in 2 patients on spironolactone. Conclusions: Spironolactone is more effective than furosemide for control of BP in RHT patients, with positive added effect on albuminuria. Spironolactone is safe in patients with mild kidney impairment, although serum potassium should be closely monitored, especially in diabetics.