Predictors of Controlled Ambulatory Blood Pressure in Treated Hypertensive Patients with Uncontrolled Office Blood Pressure

High-density lipoprotein cholesterol and insulin resistance are independent and additive markers of left ventricular hypertrophy in essential hypertension

We examined whether plasma high-density lipoprotein-cholesterol (HDL-C) levels and glucose metabolism parameters are independent or additive predictors of left ventricular hypertrophy (LVH) in patients with untreated essential hypertension. The study group consisted of 41 Japanese patients with untreated essential hypertension and LVH (left ventricular mass index [LVMI] >125 g/m2; age 58+/-6 years, mean+/-SD), and the control group consisted of 39 age-matched patients with untreated essential hypertension without LVH (LVMI <or=125 g/m2; age 58+/-7 years). The following metabolic parameters were higher in the group with LVH: fasting plasma glucose (FPG) (p<0.01), fasting insulin concentration (F-IRI) (p<0.0001), and homeostasis model assessment (HOMA)-index (p<0.0001). Among the laboratory parameters investigated, plasma HDL-C levels were lower (p<0.0001), and triglyceride and uric acid levels were higher in the group with LVH (p<0.05 for both). The nighttime systolic and diastolic ambulatory blood pressure (ABP) (p<0.0001, p<0.01, respectively) and nighttime heart rate (p<0.01) were higher in patients with LVH. Multivariate logistic analysis identified HDL-C (odds ratio [OR]=0.92, 95% confidence interval [CI]=0.87-0.98, p<0.05), HOMA-index (OR=3.83, 95% CI=1.28-11.5, p<0.05) and nighttime systolic ambulatory blood pressure (ABP) (OR=1.06, 95% CI=1.00-1.13, p<0.05) as independent significant risk factors for LVH. Our findings suggest that HDL-C, HOMA-index and nighttime systolic ABP are independent predictors for the presence of LVH in Japanese patients with essential hypertension.

Estimation of base blood pressure by using a new device in the outpatient clinic

Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic.

Long-Term and Strict Blood Pressure Lowering by Imidapril Reverses Left Ventricular Hypertrophy in Patients with Essential Hypertension: An Evaluation Using a Novel Indicator of Burden on the Left Ventricle

Left ventricular hypertrophy is an independent risk factor for cardiovascular disease. We evaluated the effect of long-term and strict antihypertensive therapy with and without the angiotensin-converting enzyme inhibitor (ACEI) imidapril on left ventricular hypertrophy using a novel indicator of chronic burden on the left ventricle, the area under the blood pressure curve x the duration of high blood pressure (AUSBP and AUDBP), in patients with essential hypertension. The patients were divided into 2 groups: an ACEI group, in which imidapril was used in addition to antihypertensive drugs such as Ca channel blockers, beta-blockers, diuretics or angiotensin II antagonist; and a non-ACEI group, in which Ca channel blockers and diuretics were used. Systolic and diastolic blood pressures (SBP and DBP) were both maintained at below 140 and 90 mmHg, respectively, for 2 years. There was no significant difference in the left ventricular mass (LVM) assessed by echocardiography at baseline and that at 2 years of follow-up in the non-ACEI group. However, the LVM in the ACEI group was significantly decreased at 2 years of follow-up as compared to that at the baseline visit. There was no difference in the mean AUSBP and AUDBP between the ACEI and non-ACEI groups. Changes in the LVM were not correlated with the AUSBP or AUDBP in both the ACEI and non-ACEI groups. These findings suggest that the decrease in the LVM in the ACEI group was mediated through mechanisms other than the blood pressure lowering-effect and that AUSBP and AUDBP may be novel indicators of the long-term burden on the left ventricle.