本態性高血圧症の血圧の概日変動に対する塩酸Ｂｕｎａｚｏｓｉｎの効果についての検討

Abstract

An open and non-randomized study was performed employing 10 patients (average age 54 years, 6 male and 4 female) with untreated essential hypertension to evaluate the efficacy on the circadian variation of blood pressure of bunazosin hydrochloride for more than 4 weeks. Mean values of systolic and diastolic blood pressure and heart rate for 48 hours every 30 minutes were obtained before and after the treatment using a noninvasive ambulatory monitor (model ABPM-630, Nippon Colin Inc., Japan). Each patient was administered bunazosin hydrochloride at a dose of 1 mg t. i. d. for more than 4 weeks. The data were analyzed with a conventional statistical method, hyperbaric index and the cosinor method during the day active and the night resting span, respectively. Systolic blood pressure (SBP) was significantly decreased from 160±6 to 152±7 mmHg (P<0.05) during the day active span, but this decrease was not significant during the night resting span. Diastolic blood pressure (DBP) also decreased significantly during the day active span, but not significantly during the night resting span. Hyperbaric indices and fractionated hyperbaric indices (hyperbaric index for every 4-hours) did not show a change in systolic and diastolic blood pressure or heart rate. MESOR (midline estimating statistic of rhythm) decreased significantly in SBP (p<0.05) and in DBP (p<0.01), however, circadian amplitude and acrophase did not change. 48-hour mean, means during the day active and during the night resting span, MESOR, amplitude and acrophase in heart rate did not show significant changes. In summary, bunazosin hydrochloride had antihypertensive effects on SBP and DBP especially during the day active span, but these were less effective on SBP and DBP during the night resting span and heart rate by this regimen.