Isolated office hypertension and end-organ damage

Significance of ambulatory blood pressure monitoring in assessment of potential living kidney donors

The most recent British Transplant Society (BTS) guidelines recommend that office blood pressure (BP) monitoring in living donors is sufficient for the assessment of hypertension (HTN) and those with BP >140/90 should be further assessed using ambulatory BP monitoring (ABPM). ABPM can detect diurnal and nocturnal variation in BP, thus it can identify masked HTN. The aim of the current study is to assess reliability of ABPM vesus office BP monitoring for assessment in living kidney donors. Office and ABPM of all potential kidney donors at a single center from April 2009 to March 2017 were retrospectively reviewed and compared. Age, sex, body mass index, kidney function, and echocardiography results were collected and analyzed. Two hundred and sixteen kidney donors were stratified based on their BP readings into four groups; group 1 (masked HTN: normotensive in office and hypertensive in ABPM), group 2 (sustained normotension: normotensive in office and in ABPM), group 3 (sustained HTN: hypertensive in office and in ABPM), group 4 (white-coat HTN: hypertensive in office and normotensive in ABPM). Thirteen percent of patients were diagnosed with masked HTN. Office systolic BP monitoring was significantly higher in patients older than 50 years old compared to other younger populations. However, this significant difference in systolic BP was diminished when assessment with ABPM was performed. In conclusion, ABPM is a reliable modality for the identification of masked HTN and white coat HTN. Masked HTN is correlated with increased risk of end organ damage and risk of death in potential kidney donors. Transplant physicians cannot rely solely on office BP monitoring in the assessment of potential living kidney donors. ABPM should be integral part of routine assessment of potential living kidney donors.

Left ventricular mass index in children with white coat hypertension

OBJECTIVES

To determine whether children with white coat hypertension (WCH) have evidence of target-organ damage by comparing the left ventricular mass index (LVMI) of subjects with WCH with that of matched normotensive and hypertensive controls.

STUDY DESIGN

Each subject in the WCH group was matched by body mass index (BMI; +/- 10%), age (+/- 1 year), and sex to a normotensive control and a hypertensive control. Echocardiograms were reviewed to determine the LVMI for each subject. These triple matches were analyzed using repeated-measures analysis of variance to detect differences in LVMI among the 3 groups.

RESULTS

A total of 27 matched triplets were established. The groups were comparable for sex, age, and BMI. Mean LVMI was 29.2 g/m(2.7) for the normotensive group, 32.3 g/m(2.7) for the WCH group, and 35.1 g/m(2.7) for the sustained hypertensive group (normotensive vs WCH, P = .028; WCH vs sustained hypertension, P = .07). Left ventricular hypertrophy was not present in any subject in the normotensive or WCH groups, but was found in 26% of the sustained hypertensive subjects (P < .001).

CONCLUSIONS

After controlling closely for BMI, the LVMI in the subjects with WCH was between that of the normotensives and sustained hypertensives, suggesting that WCH may be associated with hypertensive end-organ effects.

Routine Use of Ambulatory Blood Pressure Monitoring in Potential Living Kidney Donors

BACKGROUND AND OBJECTIVES

Most transplant centers exclude prospective living kidney donors with hypertension from donation. Centers routinely identify hypertension using BP measured in the clinic, but it is not clear that clinic BP accurately detects the presence or absence of hypertension in potential donors. We therefore conducted a prospective study to determine the impact of routine ambulatory BP monitoring on diagnosis of hypertension in potential donors and the value of other baseline characteristics in predicting ambulatory BP results.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We compared classification of hypertension status by clinic BP and by ambulatory BP monitoring in 178 potential living kidney donors.

RESULTS

Of 63 individuals with hypertension by clinic BP, 62% had white-coat hypertension by ambulatory BP and were therefore eligible to donate. Of 115 individuals who were normotensive by clinic BP, 17% had masked hypertension by ambulatory BP and were excluded from donation. Individuals with masked hypertension were older, were more likely to be male, and had a somewhat higher clinic BP than individuals with sustained normotension. Individuals with white-coat hypertension had a somewhat lower clinic diastolic BP than individuals with sustained hypertension.

CONCLUSIONS

Routine ambulatory BP monitoring may identify a large number of individuals with white-coat hypertension and a smaller but significant number of individuals with masked hypertension, ensuring adequate protection of potential donors and accurate assessment of donor risk. Differences in baseline characteristics are small and are not clinically useful in distinguishing individuals with masked hypertension from individuals with sustained normotension or individuals with white-coat hypertension from individuals with sustained hypertension, demonstrating the importance of ambulatory BP monitoring in this population.

Cardiac structure and function and arterial circulation in hypertensive patients with and without metabolic syndrome

High blood pressure (BP) is one of the crucial determinants of the metabolic syndrome (MS). The extent to which MS, diagnosed according to the criteria of the International Federation of Diabetes, impacts on cardiovascular organ damage, independently of BP, is debated. Three hundred and forty hypertensive patients and 100 normotensive controls underwent the following procedures: (1) physical examination and resting BP measurements, (2) 24 h ambulatory BP monitoring, (3) laboratory routine examination, (4) echocardiography, (5) carotid ultrasonography and (6) ankle-brachial BP index. The syndrome was found in 104 of the 340 hypertensive patients (30.6). In comparison to those without MS, those with MS had significantly higher prevalence of left ventricular (LV) hypertrophy by mass/height(2.7) criteria (46 vs 42%, P<0.01) but not by LV mass/body surface criteria (30 vs 31%); the ratio between early-to-late peak velocities of the LV filling waves (E/A) was higher (E/A=0.99+/-0.14 vs 0.89+/-0.15, P<0.01) and left atrium was larger (3.8+/-0.3 vs 3.5+/-0.5 cm, P<0.01). Both hypertensive groups had significantly greater LVM and carotid intima-media thickness than normotensives, without between-group-difference. In this hypertension outpatient clinic almost one-third hypertensive patients have MS. They show a deterioration in structure and function of the heart in comparison to hypertensive patients without MS, but no difference was detected in the carotid and peripheral arterial circulation.

Blood pressure at rest, during 24 h monitoring and in response to sympathetic stimulation in hypertensive patients with metabolic syndrome

OBJECTIVE

As subjects with metabolic syndrome have an increased sympathetic activity regardless of the presence of arterial hypertension, this study aimed at evaluating in hypertensives whether this condition has repercussions on differences in resting, ambulatory and under sympathetic stimulation blood pressure levels.

METHODS

Blood pressure (BP) was measured at rest and in response to isometric exercise and cold pressure test by zero-random sphygmomanometer. Moreover 24 h BP monitoring was performed by using Spacelabs 90207.

RESULTS

Of the 340 hypertensive patients entering the study, 110 (32%) had metabolic syndrome. They were older (47 vs. 42 years, p<0.01) than those without MS and, by definition, had increased body mass index, fasting blood glucose and triglycerides and lower HDL-cholesterol. Also BP at rest (148/95 vs. 140/90 mm Hg, p<0.01), during 24 h (138/89 vs. 129/84 mm Hg, p<0.001) as well as during daytime and nighttime were significantly increased in this group. No difference, on the other hand, was detected in the response to tests stimulating sympathetic nervous system and in the clinic-daytime BP difference.

CONCLUSIONS

In the present study hypertensive patients with MS have higher BP, both at rest and during ambulatory monitoring in comparison to hypertensives without MS. The BP response to the stimulation of the sympathetic system seems, on the other hand, similar probably because the presence of hypertension in both groups masks during maximal stress the differences evident in less stressing conditions.

Prevalence of masked uncontrolled and treated white-coat hypertension defined according to the average of morning and evening home blood pressure value: from the Japan Home versus Office Measurement Evaluation Study

OBJECTIVE

To evaluate the prevalence of masked uncontrolled and treated white-coat hypertension defined according to the average of morning and evening home blood pressure values.

METHODS

The study population consisted of 3303 essential hypertensive outpatients receiving antihypertensive treatment in Japan. Information on the characteristics of the patients was collected by a physician's self-administrated questionnaire. The office blood pressure value was calculated as the average of the four readings in two visits. All patients were asked to measure their blood pressure once every morning and once every evening. In the study, we included patients with at least three measurements in the morning and in the evening, respectively. The average of all home blood pressure values was taken as the home blood pressure value.

RESULTS

The mean value of home systolic/diastolic blood pressure was 136.8/79.3 mmHg, and the mean value of office systolic/diastolic blood pressure was 142.8/80.6 mmHg. Of the 3303 patients, 758 (23.0%) had controlled hypertension (home <135/85 mmHg and office <140/90 mmHg), 628 (19.0%) had masked uncontrolled hypertension (home > or =135/85 mmHg and office <140/90 mmHg), 640 (19.4%) had treated white-coat hypertension (home <135/85 mmHg and office > or =140/90 mmHg), and 1277 (38.7%) had uncontrolled hypertension (home > or =135/85 mmHg and office > or =140/90 mmHg).

CONCLUSIONS

Treated white-coat hypertension and masked uncontrolled hypertension were often observed in clinical settings. Physicians need to understand the prevalence of such patients to prevent inadequate diagnosis and treatment in them.

White-coat hypertension: a clinical review

White-coat hypertension (WCHT), also called 'isolated office or clinic hypertension', is defined as the occurrence of blood pressure (BP) values higher than normal when measured in the medical environment, but within the normal range during daily life, usually defined as average daytime ambulatory BP (ABP) or home BP values (<135 mm Hg systolic and <85 mm Hg diastolic). The prevalence of WCHT varies from 15% to over 50% of all patients with mildly elevated office BP (OBP) values. In untreated hypertensive patients, the probability of WCHT especially increases with female gender and a mildly elevated OBP level. The value of other possible determinants such as (non) smoking status, duration of hypertension, left ventricular mass, number of OBP measurements, educational level, etc. is less consistently shown. Although, for various reasons, studies evaluating the long-term effects of WCHT are not always easy to interpret, most data indicate that persons with WCHT have a worse or equal cardiovascular prognosis than normotensives, but a better one than those with sustained hypertension. WCHT is sometimes considered a prehypertensive state, but data on the long-term evolution of subjects with WCHT are scarce. Patients with WCHT and a high cardiovascular risk or proven target organ damage should be pharmacologically treated. Subjects with uncomplicated WCHT should probably not receive medical therapy, but a close follow-up, including regular assessment of other risk factors and measurement of OBP (every 6 months) and ABP (every 1 or 2 years), is warranted.

White Coat Hypertension in Patients With Obstructive Sleep Apnea-Hypopnea Syndrome

BACKGROUND

The strength of the association between obstructive sleep apnea-hypopnea syndrome (OSAHS) and systemic hypertension could be affected by methodologic problems in the definition of hypertension.

STUDY OBJECTIVES

To determine the frequency of white coat hypertension (WCH) in patients with OSAHS, and to analyze the characteristics of patients with OSASH and WCH.

PATIENTS AND INTERVENTIONS

Ninety-nine consecutive patients with OSAHS and 20 healthy control subjects were included into the study. Twenty-four-hour ambulatory BP monitoring (ABPM) and urinary catecholamines were determined simultaneously with the polysomnographic study. Arterial blood gases and lung volumes were also measured.

RESULTS

Office hypertension was diagnosed in 45 patients, while the control group included 54 normotensive patients with OSAHS. After ABPM, hypertension was confirmed in 30 patients with OSAHS and office hypertension. WCH was diagnosed in the remaining 15 patients (33%). Patients with WCH presented higher values of sleep onset latency and wake after sleep onset than normotensive and sustained hypertensive patients. No other differences in sleep parameters, function tests, or urinary catecholamines were found between the OSAHS groups.

CONCLUSION

The results indicate that WCH is a frequent phenomenon in patients with OSAHS, and that it is not predictable by clinical variables.

High prevalence of Chlamydia pneumoniae antibodies in white-coat hypertensives

Previous studies have linked essential sustained hypertension with Chlamydia pneumoniae (C. pneumoniae) and changes in intima-media thickness (IMT) of carotid arteries. The aim of this study was to examine if similar associations exist in subjects with white-coat hypertension. C. pneumoniae IgA and IgG antibody titers were measured in 125 patients with white-coat hypertension and 54 normotensives. All participants underwent a 24 h ambulatory blood pressure (BP) monitoring, clinic BP readings and common-internal carotid artery IMT measurements. Seventy subjects of the white-coat group (56%) and 15 of the control group (27.8%) had IgG titers >/=80 (crosstabs; P<0.001). IgA titers were elevated in 75 subjects of the white-coat group (60%) and 10 (18.5%) of the control group (crosstabs; P<0.001). The IMT of the carotid arteries in the white-coat group was significantly higher than that of the normotensive group (t-test; P<0.001 and P<0.001, respectively). In contrast, carotid IMT did not differ between C. pneumoniae-seropositive and C. pneumoniae-seronegative groups concerning both IgG and IgA antibody titers. Our findings suggest that both C. pneumoniae antibody titers and carotid IMT were increased in subjects with white-coat hypertension. The preceding associations strengthen prior evidence in favor of the opinion that white-coat hypertension is not an innocent phenomenon.

Circulating homocysteine levels in sustained and white coat hypertension

Although white coat hypertension has been widely studied in the last years, its risk profile is not yet completely clear. The aim of this study was to evaluate circulating homocysteine levels, an emerging cardiovascular risk factor, in subjects with white coat and sustained hypertension. We selected 31 sustained hypertensive subjects, 31 white coat hypertensive subjects and 31 normotensive subjects matched for age, gender, body mass index and occupation. Women were also matched for menopausal status. Subjects with smoking habit, dyslipidaemia and diabetes mellitus were excluded from the study. White coat hypertension was defined as clinical hypertension and daytime ambulatory blood pressure <135/85 mmHg. Blood samples were drawn after a fasting period of 12 h for routine laboratory tests and homocysteine determination. Homocysteine levels were evaluated by fluorescence polarization immunoassay. Creatinine, glucose, cholesterol and triglycerides were not different among the groups. White coat hypertensive subjects had significantly lower homocysteine levels than sustained hypertensive patients (8.2+/-2.0 vs 12.6+/-3.9 micromol/l, P=0.0003). No significant difference was observed between white coat hypertensive and normotensive subjects regarding this parameter (8.2+/-2.0 vs 7.6+/-1.9 micromol/l, P=0.9). In conclusion, our data show that middle-aged white coat hypertensive subjects without other cardiovascular risk factors have lower circulating homocysteine levels than sustained hypertensive patients suggesting that they are at lower cardiovascular risk.

Clinic and ambulatory heart rate in sustained and white-coat hypertension

BACKGROUND

Sustained and white-coat hypertensives show hypertension in the office setting but different blood pressure values outside the clinical environment. So far, only a few incomplete data on heart rate are available inside and outside the clinical setting in these groups of patient. The aim of this study was to evaluate clinic and ambulatory heart in sustained hypertensives, white-coat hypertensives and normotensives.

METHODS

We selected 236 sustained hypertensives, 236 white-coat hypertensives and 236 normotensives matched for age, gender and body mass index, and with a similar occupation. The subjects had been submitted to clinic evaluation and the non-invasive monitoring of blood pressure and heart rate. White-coat hypertension was defined as clinic hypertension and a daytime blood pressure of less than 135/85 mmHg.

RESULTS

The clinic heart rate was significantly higher in sustained hypertensives and white-coat hypertensives than in normotensives (76 +/- 11 versus 75.5 +/- 10 versus 70 +/- 9 beats/min [bpm], respectively, P < 0.05). The daytime heart rate was significantly higher in sustained hypertensives than in white-coat hypertensives and normotensives (79.4 +/- 10 versus 74.6 +/- 8.5 versus 74.5 +/- 8.5 bpm, respectively, P < 0.05), as were the night-time heart rate (67 +/- 8.5 versus 63 +/- 8 versus 63 +/- 8 bpm, respectively, P < 0.05) and 24 h heart rate (76.3 +/- 9 versus 72 +/- 7.8 versus 72 +/- 8 bpm, respectively, P < 0.05). When men and women were analyzed separately, the same trend was observed.

CONCLUSIONS

The clinic heart rate is similar in sustained and white-coat hypertensives, but the ambulatory heart rate is lower in white-coat hypertensives. As ambulatory heart rate is more representative of 24 h heart rate load and may be a better indicator of the detrimental effect of heart rate, our findings suggest that white-coat hypertensives are at lower cardiovascular risk than sustained hypertensives.

[Evolution of white coat hypertension to sustained hypertension. One year follow-up by ambulatory blood pressure monitoring]

BACKGROUND

To analyse the evolution of the white coat hypertension (WCH) to sustained hypertension, by means of ambulatory blood pressure monitoring (ABPM) during the first year after its diagnosis.

SUBJECTS AND METHOD

A prospective study of cohorts was designed in La Orden Health Center of Huelva, Spain. 86 individuals divided in two groups: a) group not exposed (GNE): 43 voluntary normotensives, and b) group exposed (GE): 43 individuals with WCH, defined as the blood pressure was superior or above 140 and/or 90 mmHg, respectively, with a mean diurnal ABPM below 135 and 85 mmHg in both cases. A ABPM was performed (Spacelabs 90207) at the beginning of the study, after 6 months and after 12 months. The clinical and ambulatory blood pressure and the incidence of sustained hypertension by ABPM in the two groups were compared. Sustained hypertension was considered when the diurnal blood pressure was superior to 135 and/or 85 mmHg for SBP and DBP.

RESULTS

At the end of the study, 82 patients were evaluate. The incidence of hypertension at 6 months of follow-up was of 4,76% (CI, 0-26.9) in GNE and 19.04% (95% CI, 0-42,6) in GE (RR: 3.8; 95% CI, 0.86-16.9) (p = 0.052). At one year of follow-up the incidence of hypertension in GNE was of 9.8% (95% CI, 0.31-1) as opposed to 46.3% (95% CI, 20.5-72.1) in GE (RR: 4.63; CI, 1.7-12.4) (p = 0.001).

CONCLUSIONS

The patients with WCH present a higher incidence of hypertension as compared to the normotensives, after 12 months of our follow-up.

Impact of blood pressure control on prevalence of left ventricular hypertrophy in treated hypertensive patients

AIM

The aim of the present study was to evaluate (1) the prevalence and patterns of left ventricular hypertrophy (LVH) and (2) the impact of blood pressure (BP) control, assessed by clinical and 24-hour ambulatory BP monitoring (ABPM) criteria on the persistence of LVH in a representative sample of treated patients attending our Hypertension Clinic.

METHODS

One hundred consecutive essential hypertensives (61 m/39 f, age 56+/- 9 years) regularly followed up by the same medical team (average period 52 months, 12-156 months) were included in the study and underwent 24-hour ABPM and complete echocardiographic examination.

RESULTS

Twenty-eight of the 100 patients were found to have LVH [left ventricular mass index (LVMI) >125 g/m(2) in men and >110 g/m(2) in women]; LVH was eccentric in 20 patients and concentric in the remaining 8. LVMI did not correlate with clinical BP values but only with ABPM values (mean 24 h systolic r = 0.34, p <0.01; diastolic r = 0.37, p <0.01). The prevalence of LVH in patients controlled according to clinical BP criteria (n = 43, BP <140/90 mm Hg) was 19%, in patients controlled according to ABPM criteria (n = 30, BP during daytime <132/85 mm Hg) 17%, and in those controlled with both criteria (n = 16) 6% (p <0. 01).

CONCLUSIONS

The results of this study suggest that the eccentric type of LVH is the prevalent pattern in chronically treated patients. The persistence of LVH is significantly dependent on BP levels achieved during treatment; indeed the prevalence of LVH is very low in patients with an optimal BP control, whereas it is elevated (37%) in uncontrolled patients.

Clinical value of ambulatory blood pressure monitoring

Ambulatory blood pressure monitoring (ABPM) has now become an established clinical tool. It is appropriate to take stock and assess the situation of this technique. UPDATE ON EQUIPMENT: Important improvements in equipment have occurred, with reductions in weight, in awkwardness and in noisiness of the machines, better acceptability and tolerance by the patients, and better reliability. Validation programmes have been proposed and should be referred to. Limitations of the technique persist with intermittent recording in current practice. The reproducibility is limited in the short-term while recording over 24 h is acceptable. DIAGNOSIS AND PROGNOSIS: White-coat effect (WCE) is manifested as a transient elevation in blood pressure during the medical visit The frequency of this phenomenon, the size of the effect, age, sex and level of blood pressure (BP) or the situation of occurrence (general practitioner, specialist or nurse) have been interpreted differently. It does not seem that WCE predicts cardiovascular morbidity or mortality. White-coat hypertension (WCH) is diagnosed on the evidence of abnormal clinical measures of BP and normal ABPM. The latest upper limits of normality by ABPM recommended by the JNCVI are < 135/85 mmHg while patients are awake and < 120/75 mmHg while patients are asleep. If we accept these upper limits of normality in ABPM, WCH does not appear to be a real problem as regards risk factors or end-organ effects. In terms of prognosis, data are limited. Cardiovascular morbidity seems low in WCH but identical to that of hypertensive subjects in these studies. However, further studies are needed to confirm these results. WCH does not appear to benefit from anti-hypertensive treatment. It is obvious that the lower the BP regarded as the limit of normality, the less likely the occurrence of secondary effects of metabolism, or end-organ effects or complications in those classified as hypertensive. 24 HOUR CYCLE: One of the most specific characteristics of ABPM is the possibility of being able to discover modification or alteration of the 24 h cycle of BP. Non-dippers are classically defined as those who show a reduction in BP of less than 10/5 mmHg or 10% between the day (06.00-22.00 h) and the night, or an elevation in BP. In contrast, extreme dippers are those in whom the BP reduction is greater than 20%. CARDIOVASCULAR SYSTEM: The data remain inconclusive with regard to the existence of a consistent relationship between the lack of a nocturnal dip in blood pressure and target organ damage. As regards prognosis, it seems that an inversion of the day-night cycle is of pejorative significance. CEREBROVASCULAR SYSTEM: Almost all studies have shown that non-dippers had a significantly higher frequency of stroke than dippers. In contrast, too great a fall in nocturnal BP may be responsible for more marked cerebral ischaemia. RENAL SYSTEM: Non-dippers have a significantly elevated median urinary excretion of albumin. There is a significant correlation between the systolic BP and nocturnal diastolic BP, and urinary excretion of albumin. Various studies have confirmed the increased frequency of change in the 24 h cycle in hypertensive subjects at the stage of renal failure.

DIABETES

BP abnormalities should be considered as markers of an elevated risk in diabetic subjects but cannot be considered at present as predictive of the appearance of micro-albuminuria or other abnormalities. ABPM is thus of interest in type I or type II diabetes both in the initial assessment and in the follow-up and adaptation of treatment. PHARMACO-THERAPEUTIC USES: The introduction of ABPM has truly changed the means and possibilities of approach to the study of the effects of anti-hypertensive medications, with new possibilities of analysis such as trough-peak ratio smoothness index, etc.

Clinic-daytime blood pressure difference and cardiovascular damage

OBJECTIVE

To investigate whether the clinic-daytime blood pressure difference can provide information on vascular reactivity to stress comparable to that of simple noninvasive stimuli such as a cold pressor test and isometric exercise, and whether there is any relationship between this blood pressure difference and noninvasive measurements of the left ventricular mass and carotid arterial wall.

DESIGN

Patients with newly discovered, never-treated, sustained hypertension were included in the study after a 1 month run-in, during which time their blood pressure was measured three times at 2 week intervals.

METHODS

Blood pressure was measured by a noninvasive procedure at rest and during a cold pressor test and an isometric exercise. The difference was calculated for systolic, diastolic and mean blood pressure as resting minus daytime ambulatory blood pressure. Parameters of the posterior wall and septal thickness of the left ventricle, aortic root and left atrium were studied by M-mode echocardiography. Carotid wall thickness and diameter were measured using ultrasound.

RESULTS

The 90 patients enrolled in the study were divided into tertiles of clinic-daytime blood pressure difference. The composition of the groups differed in sex, since the majority of women were in the highest tertile, but was comparable for age, body mass index, renin-aldosterone axis and lipid and carbohydrate metabolism. Blood pressure responses to cold and isometric exercise were more pronounced in patients in the lowest tertile of blood pressure difference. No intergroup differences were detected in echocardiographic parameters of ventricular (left ventricular mass, tertiles I-III: 46.5 +/- 10, 42.3 +/- 8, 44.8 +/- 13 g/m2.7, respectively) and carotid (intima-media thickness, tertiles I-III 0.58 +/- 0.1, 0.54 +/- 0.1, 0.62 +/- 0.1 mm, respectively) structure.

CONCLUSIONS

The present study indicates that the clinic-daytime blood pressure difference provides different information on cardiovascular reactivity compared with that obtained from the cold pressor test and isometric exercise. Moreover, it does not seem to have any relationship with ventricular hypertrophy and/or carotid wall thickening.