ABSTRACT
BACKGROUND: Conflict still exists over whether patients with white-coat hypertension are at increased risk of developing target organ damage compared with normotensive individuals. METHODS: We studied vascular distensibility in 117 young-to-middle age patients with white-coat hypertension, 174 patients with sustained hypertension, and 51 normotensive controls. To obtain a measure of compliance, a model was used that divides the total systemic compliance into large artery (C1) and small artery (C2) compliance. With this aim, radial arterial pulse waves were recorded with a tonometer sensor array by means of an HDI CR2000 device (Eagan, Minnesota, USA). Moreover, pulse wave velocity and the augmentation index were measured using the Specaway DAT system (St Pauls, Sydney, Australia). RESULTS: Patients with sustained hypertension had a greater body mass index than patients with white-coat hypertension (P=0.04) or the normotensive individuals (P=0.01). C1 and C2 were decreased in the two hypertensive groups as compared with those in the normotensive group (P=0.0002 and 0.03, respectively, versus sustained hypertension; P=0.00007 and 0.0004, respectively, versus white-coat hypertension). Pulse wave velocity and aortic augmentation index were increased in the white-coat hypertension patients compared with the normotensive individuals (P=0.02 and 0.004, respectively). Aortic augmentation index (P=0.008) but not pulse wave velocity was increased in the sustained hypertensive patients compared with that in the normotensive individuals. All indexes of arterial distensibility were similar in the two hypertensive groups. CONCLUSIONS: Indexes of arterial distensibility are impaired in the white-coat hypertensive group and similar to those in the sustained hypertensive group, indicating that early changes in the arterial wall can occur in white-coat hypertension. This may account for the higher risk of stroke that has been described in this condition.
Subject(s)
Blood Pressure/physiology , Hypertension/physiopathology , Pulsatile Flow/physiology , Radial Artery/physiopathology , Adult , Age Distribution , Blood Pressure Determination/standards , Compliance , Elasticity , Female , Humans , Hypertension/diagnosis , Hypertension/epidemiology , Male , Physicians' Offices , Reproducibility of Results , Risk Factors , Sex Distribution , Stroke/epidemiologyABSTRACT
OBJECTIVES: To determine the accuracy of the UA-631 (UA-779 Life Source for the American market) blood pressure monitor developed by the A&D Company (Toshimi-ku, Tokyo, Japan). DESIGN: Device evaluation was performed using a new protocol proposed by the Working Group on blood pressure monitoring of the European Society of Hypertension (ESH). Monitor performance was assessed in relation to subjects' gender, age, skinfold thickness, arm circumference, BMI, and elasticity index of large (C1) and small (C2) arteries. METHODS: The A&D recorder was assessed according to the various phases of the protocol. Sequential readings were taken for the main validation test. Outcome was classified according to the criteria of ESH recommendations, which are based on four zones of accuracy differing from the mercury standard by 5, 10, 15 mmHg, or more. RESULTS: The main validation test was performed in 66 subjects for a total of 198 device measurements. The A&D monitor passed all three phases both for systolic and diastolic blood pressure (SBP and DBP). Mean blood pressure difference between device and observers was 2 +/- 5 mmHg for SBP and 1 +/- 3 mmHg for DBP. The absolute discrepancy between device and observers (4 +/- 4 mmHg for SBP, and 2 +/- 2 mmHg for DBP) was related to age (negatively) and to C1 (positively), but in a multivariable regression analysis only C1 remained a significant independent predictor of the absolute device-observer discrepancy. CONCLUSIONS: These data show that the A&D UA-631 device satisfies the new recommended ESH accuracy levels for both SBP and DBP. Its performance seems to be better in subjects with stiffer arteries.
