Morning blood pressure surge in patients with mild to moderate arterial hypertension and a method of correction with metoprolol retard

Background. The evaluation of the effect of prolonged-effect metoprolol therapy on morning blood pressure elevation with ambulatory blood pressure monitoring (ABPM) in patients with mild to moderate arterial hypertension was the purpose of our study. Materials and methods. 118 patients were included in the study. We have evaluated systolic (SBP) and diastolic blood pressure (DBP), heart rate, patient’s compliance, adverse reactions, efficacy of therapy at baseline and on weeks 2, 4, 8 of treatment. Ambulatory blood pressure monitoring was performed in all patients before and on 2 nd month of therapy. Metoprolol was administered in initial daily dose 25 mg per day, and then the dose was up titrated every 10 days to 300 mg daily. If monotherapy was ineffective, hydrochlorothiazide was added (25 mg per day). Data of ABPM were obtained in 118 patients. In addition to the 24-hour active and passive periods, average parameters for a special period (6:00–12:00) were calculated, as well as indicators of the level of SBP increase in the morning hours and the rate of maximum SBP increase in the mor-ning hours. The level of the maximum SBP surge in the mor-ning was determined. The mean age of patients was 56.20 ± 0.76 years, the body mass index — 28.90 ± 0.35 kg/m 2 . The baseline level of office mean SBP and DBP as a whole for the group was 164.2 ± 0.9 mmHg and 96.8 ± 0.7 mmHg, respectively. Results. It was established that in mild and moderate hypertensive patients, metoprolol retard (alone or in combination with hydrochlorothiazide) decreased the office SBP and DBP by 32 and 18 mmHg, respectively, heart rate — by 18 beats per min (p < 0.001). Also, average daily SBP and DBP decreased by 21 and 13 mmHg (p < 0.05), average daytime SBP and DBP — by 23 and 12 mmHg (p < 0.05), and nighttime SBP and DBP — by 21 and 12 mmHg (p < 0.05). The average daily heart rate reduced by 7 bpm (p < 0.05), the average daytime heart rate — by 7.4 (p < 0.05), and nighttime — by 5.5 beats per minute (p < 0.05), respectively. Target BP according to ABPM (< 125/80 mmHg) was achieved in 64.4 % of patients. The target office blood pressure (< 140/90 mmHg) was reached in 93.6 % of patients. There was a significant decrease in mean SBP, DBP, pulse pressure for a special period by 20, 11 and 8 mmHg, respectively, a decrease in the temporal index for SBP and DBP (from 85.10 ± ± 1.35 and 67.1 ± 2.2 % to 56.80 ± 2.84 % and 43.10 ± 2.72 %, p < 0.05) and pressure load index for SBP and DBP (from 499.5 ± 28.4 and 243.10 ± 17.27 mmHg to 247.30 ± 24.01 and 103.10 ± 10.53 mmHg, p < 0.05). The mean decrease of the maximum SBP in the morning was 29 mmHg (р < 0.001). The level of SBP surge in the morning hours significantly decreased from 60.9 ± 1.9 to 50.5 ± 1.7 mmHg (p < 0.05). The dyna-mics of the decrease in the rate of the maximum SBP increase in the morning hours was not significant. We did not register any negative biochemical changes. Only 16 (12.1 %) adverse events were noted. Conclusions. In patients with mild to mode-rate arterial hypertension, taking metoprolol retard at a dose of 100–300 mg once a day contributed to a significant decrease in the maximum level of systolic blood pressure and the degree of its increase in the morning.