title: Effect of Quinapril on the Circadian Blood Pressure Pattern Evaluated by Periodic Analysis of Covariance.
abstract: The effects of quinapril on casual blood pressure (BP) and circadian variations in 24-h blood pressure (24ABPM) were studied in patients with essential hypertension. Twenty-six patients were enrolled in the study (mean age 59 plus minus 11 years). After a 4-week washout period, patients, were treated with quinapril 5 mg, 10 mg, or 20 mg once a day until casual blood pressures become optimal within 8--10 weeks. The 24ABPM was performed before and after treatment at 30-min intervals using an ABPM-630 in patients during usual daily activities on the work days. Measured BP was fitted to a periodic regression curve with 24-h and 12-h harmonics. Quinapril significantly decreased casual blood pressure but had no effect on pulse rate. It exhibited an excellent antihypertensive effect throughout 24 h; this effect, however, was stronger during the day than at night, resulting in no excessive nocturnal hypotension. The level of the periodic regression curves for systolic and diastolic blood pressures was significantly decreased following treatment but that of the pulse rate was not affected by this drug. The drug caused changes in the pattern of the periodic regression curve for blood pressure and pulse rate. This was attributed to the more prominent antihypertensive effect of quinapril in the afternoon and evening. To evaluate the efficacy of this drug semiquantitatively, the hyperbaric indices were compared before and after the treatment, and those indices for both systolic and diastolic blood pressures were significantly decreased. Adverse effects occurred in four patients (15.4%), all of which were mild and thought to be clinically insignificant. It was concluded that quinapril, 5--20 mg day(minus sign1), was considered to be useful for patients with mild to moderate essential hypertension.
authors.affiliation: First Department of Internal Medicine, University of Nagoya, School of Medicine, Nagoya, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hayashi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Ohsugi
authors.forename: Masato
authors.initials: M
authors.lastname: Ishihara
authors.forename: Haruo
authors.initials: H
authors.lastname: Kamiya
authors.forename: Kyoya
authors.initials: K
authors.lastname: Inden
authors.forename: Akio
authors.initials: A
authors.lastname: Suzuki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Itoh