SPONTANEOUS ARTERIAL BAROREFLEX STATUS AS A PREDICTOR OF ANTIHYPERTENSIVE TREATMENT EFFICACY IN RESISTANT HYPERTENSION

Objective. To assess the arterial baroreflex (BR) status in patients with resistant hypertension (RHTN) and find out relationships between the baseline BR sensitivity (BRS) parameters, its dynamics and degree of blood pressure (BP) decrease during long-term antihypertensive treatment.

Design and methods. We included 46 patients (22 males and 24 females, mean age 56 ± 6 years) with non-complicated RHTN and 46 patients (22 males and 24 females, mean age 54 ± 2 years) with controlled HTN (CHTN) at baseline, who achieved the goal BP with combined antihypertensive treatment (lisinopril 20 mg/d, amlodipine 10 mg/day, hydrochlorothiazide 25 mg/day). All patients underwent ambulatory 24-hour BP monitoring (ABPM) at baseline and BRS test at rest. ABPM and BRS test at rest were performed again after 12 months of treatment.

 Results. At baseline BRS in RHTN patients was lower than in CHTN patients (5,7 ± 2,1 vs 7,0 ± 1,4 ms/mm Hg, p < 0,05). RHTN patients who did not achieve goal BP showed lower BRS at baseline and at 12-month follow up (n = 11; 23,9 %) compared to RHTN patients with target BP (n = 35; 76,1 %).

Conclusions. BR dysfunction involving the decrease of spontaneous BRS at rest is associated with RHTN. The decrease of BP observed at long-term combined antihypertensive treatment is accompanied by the BRS increase in patients with RHTN and CHTN. Insufficient efficacy of antihypertensive treatment is associated with lower baseline BRS and low increase during follow up.

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