Prevalence Of White Coat Hypertension Research Articles

Ambulatory blood pressure. An independent predictor of prognosis in essential hypertension.

To determine the prognostic significance of ambulatory blood pressure, we prospectively followed for up to 7.5 years (mean, 3.2) 1187 subjects with essential hypertension and 205 healthy normotensive control subjects who had baseline off-therapy 24-hour noninvasive ambulatory blood pressure monitoring. Prevalence of white coat hypertension, defined by an average daytime ambulatory blood pressure lower than 131/86 mm Hg in women and 136/87 mm Hg in men in clinically hypertensive subjects, was 19.2%. Cardiovascular morbidity, expressed as the number of combined fatal and nonfatal cardiovascular events per 100 patient-years, was 0.47 in the normotensive group, 0.49 in the white coat hypertension group, 1.79 in dippers with ambulatory hypertension, and 4.99 in nondippers with ambulatory hypertension. After adjustment for traditional risk markers for cardiovascular disease, morbidity did not differ between the normotensive and white coat hypertension groups (P = .83). Compared with the white coat hypertension group, cardiovascular morbidity increased in ambulatory hypertension in dippers (relative risk, 3.70; 95% confidence interval, 1.13 to 12.5), with a further increase of morbidity in nondippers (relative risk, 6.26; 95% confidence interval, 1.92 to 20.32). After adjustment for age, sex, diabetes, and echocardiographic left ventricular hypertrophy (relative risk versus subjects with normal left ventricular mass, 1.82; 95% confidence interval, 1.02 to 3.22), cardiovascular morbidity in ambulatory hypertension was higher (P = .0002) in nondippers than in dippers in women (relative risk, 6.79; 95% confidence interval, 2.45 to 18.82) but not in men (P = .91). Our findings suggest that ambulatory blood pressures stratifies cardiovascular risk in essential hypertension independent of clinic blood pressure and other traditional risk markers including echocardiographic left ventricular hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)

White coat hypertension and related phenomena. A clinical approach.

In this paper, several clinical problems associated with the diagnosis of hypertension are discussed. Blood pressure variability and reactivity are factors underlying the difficulties in the diagnosis of hypertension. These phenomena are interrelated and mixed. White coat hypertension (WCH), referring to the phenomenon of a high diastolic pressure at the doctor's office and a normal diurnal diastolic pressure when it is measured by ambulatory monitoring, is the most important clinical problem of diagnosis. Blood pressure variability is described, since it is essential to understand changes in pressure throughout the day, and its phasic and tonic components. Blood pressure differences between activity and rest, usually seen as daytime/night-time differences, allow for blood pressure control in most patients with moderate hypertension. Prevalence of WCH depends on the cut-off point used by the investigators for normal diurnal blood pressure; thus, between 53% and 12% of patients may have WCH. In our studies, a prevalence of 35% has been found. The alert reaction, labile and borderline hypertension and WCH result from a mix of both variability and reactivity, and patients with these conditions are at a higher cardiovascular risk than normotensive controls. Ambulatory blood pressure monitoring, which enables true hypertensives to be distinguished from false hypertensives, is the most useful technique available to date for the diagnosis of hypertension.

Variability between current definitions of 'normal' ambulatory blood pressure. Implications in the assessment of white coat hypertension.

The assessment of white coat hypertension is complicated by the lack of generally agreed-on normal limits of ambulatory blood pressure. To assess the influence of four of these limits on the prevalence of white coat hypertension and the corresponding distribution of left ventricular hypertrophy, we performed 24-hour ambulatory blood pressure monitoring and echocardiographic studies in 346 untreated patients with essential hypertension and 47 age-matched normotensive control subjects. The upper limits of normal daytime ambulatory blood pressure were lower using standards drawn from clinically normotensive populations than using standards drawn, partly or entirely, from general populations. The prevalence of white coat hypertension differed markedly using the different standards, being 12.1%, 16.5%, 28.9%, and 53.2% (chi 2 = 346.0, p less than 0.0001). Left ventricular mass index averaged 77 g/m2 in the control group, 85 g/m2 in the two groups with white coat hypertension defined by using standards drawn from normotensive populations (both comparisons not significant versus control group), and 90 and 98 g/m2 in the two groups with white coat hypertension defined by using the other two standards (both p less than 0.01 versus control group). The prevalence of echocardiographic left ventricular hypertrophy was 0% in the control group, 2.4% and 3.5% in the two groups with white coat hypertension defined by using standards drawn from normotensive populations, and 9.0% and 14.7% in the other two groups with white coat hypertension (p less than 0.05 and p less than 0.01, respectively, versus control group).(ABSTRACT TRUNCATED AT 250 WORDS)

4 - Forceps and Vacuum Extraction

To better define the prevalence of white coat hypertension (WCH) among patients with type 2 diabetes mellitus and to estimate the magnitude of white coat effect (WCE), before and after antihypertensive therapy, we gathered data from an open-label forced-titration study of a combination of antihypertensive drugs that was titrated sequentially, in the order amlodipine, olmesartan, and hydrochlorothiazide, over an 18-week period among 187 patients with type 2 diabetes mellitus. WCH was defined as daytime ambulatory blood pressure (BP) of 135/85 mm Hg or less, but clinic BP of 140/90 mm Hg or more. WCE was obtained as the mean difference between clinic and daytime ambulatory BP. At baseline, the prevalence of WCH was 12%; all but one subject had WCE of >10/5 mm Hg. After treatment, the prevalence of WCH had increased to 39% (P < .001). In the overall population, at baseline, the mean (±SD) WCE for systolic BP was 10.4 ± 10.9 mm Hg and 3.7 ± 8.6 mm Hg for diastolic BP. After treatment, the reduction in systolic WCE was 3.01 ± 0.93 (SE; P < .0001); no reduction was seen for diastolic WCE. Among patients treated with amlodipine-olmesartan combination, WCE at baseline was 11 mm Hg systolic and was attenuated to -0.9 mm Hg. Among patients treated with amlodipine-olmesartan-hydrochlorothiazide combination, systolic WCE was similar at baseline (10.1 mm Hg) and at end of therapy (8.1 mm Hg). Mean systolic difference between dual and triple therapy of 9.9 mm Hg, SE 2.98 was significant (P < .001). The drop in diastolic WCE from 6.4 with dual therapy to -1.2 with triple therapy was also significant (mean difference 7.6, SE 2.2; P < .001). In conclusion, the prevalence of WCH increases three-fold with treatment as a result of fewer patients having sustained hypertension. Thus, out-of-office BP monitoring especially among treated hypertensive patients with type 2 diabetes is necessary to provide better assessment of overall BP and response to treatment.

Prevalence and Predictors of White Coat Hypertension among Newly-Diagnosed Hypertensive Patients in a Tertiary Health Centre in Nigeria.

Failure to diagnose and adequately classify newly-diagnosed hypertensive patients may lead to non-recognition of White Coat Hypertension (WCH) and inappropriate use of antihypertensive medications. This study determined the prevalence and predictors of white coat hypertension among newly-diagnosed hypertensive patients in a tertiary health centre in Nigeria. One hundred and twenty newly-diagnosed hypertensive patients and 120 controls were recruited for the study. All the participants had 24-hour Ambulatory Blood Pressure Monitoring (ABPM) using an oscillometric device (CONTEC®). Data were analyzed using SPSS version 20.0. Out of 120 patients, 52 were males and the mean age was 44.2 ± 9.7 years whereas of the 120 controls, 53 were males and the mean age was 44.0 ± 7.5 years. The mean body mass index of the patients, BMI (27.0 ± 4.5kg/m2) was higher than control (24.1 ± 4.5kg/m2), p-value <0.001. The prevalence of WCH was 36.7%. The mean age and BMI of those with WCH were 43.3 ± 11.4 years and 26.4 ± 4.5kg/m2 respectively. Females constituted a greater proportion (70.5%). In multivariate analysis, high level of education and being overweight or obese were significant determinants of WCH. High prevalence of WCH existed among participants studied. High level of education and being obese were predictors of white coat hypertension. Hence, ambulatory blood pressure monitoring should be included as part of routine work-up for newly-diagnosed hypertensive patients in order to limit the number of those who may be committed to lifelong antihypertensive medications with its unwanted side effects.