Blood pressure on arising, morning blood pressure surge and blood pressure variability in white coat hypertensives and in matched normotensives and sustained hypertensives.

INTRODUCTION: It is still controversial whether subjects with white-coat hypertension (WCHT) exhibit higher cardiovascular risk compared to normotensive subjects (NT). In subjects with WCHT it is not known whether the abnormal blood pressure (BP) reaction in the office also occurs at other times of day, particularly on arising and immediately after waking, i.e. the times at which the majority of cardiovascular events are reported to occur. OBJECTIVE AND METHODS: To evaluate with 24h ambulatory BP measurement the values of morning BP surge, BP on arising and BP variability in subjects with WCHT in comparison with age-, gender- and weight-matched normotensives (BP) and untreated sustained hypertensives (BP). RESULTS: Groups of BP, WCHT and BP were matched for age, gender and body weight: BP: n=69, age 49 +/- 7 years, 54 % female, BMI 26 +/- 1, casual BP 126/79 +/- 5/4 mmHg, daytime BP 124/80 +/- 6/6 mmHg; WCHT: n=74, age 52 +/- 8 years, 57% female, BMI 26 +/- 2, casual BP 152/95 +/- 7/7 mmHg, daytime BP 126/80 +/- 5/6 mmHg; HT: n=79, age 53 +/- 7 years, 56% female, BMI 27 +/- 2, casual BP 154/97 +/- 9/8 mmHg, daytime BP 143/89 +/- 12/10 mmHg. Of the three groups, subjects with WCHT exhibited BP on arising (121/81 +/- 13/8 mmHg) similar to that of NTs (120/80 +/- 13/9 mmHg, NS), both significantly lower than that of HTs (137/92 +/- 17/10 mmHg, p < 0.01), suggesting the absence of an alerting BP reaction in WCHT at that time. By contrast, subjects with WCHT showed higher values of systolic morning BP surge vs. NTs (25 +/- 10 vs. 22 +/- 11 mmHg, p < 0.05), both lower than that observed in hypertensives (33 +/- 11 mmHg, p < 0.01 vs. NT and WCHT) and greater daytime variability (systolic BP standard variation), i.e. 12 2 vs. 10 +/- 2 mmHg, p < 0.05, both lower than that observed in hypertensives (14 +/- 3 mmHg, p < 0.01 vs. NT and WCHT). CONCLUSIONS: Although subjects with WCHT did not show any alerting blood pressure reaction on arising, morning BP surge and BP variability were greater in these subjects than in control normotensives, although lower than sustained hypertensives. Although this is still speculative, we cannot exclude the possibility that even a slight increase in morning BP surge might in the long term constitute an additional load on the circulation that could increase cardiovascular risk in subjects with WCHT compared to matched normotensives.     

Arterial distensibility in subjects with white-coat hypertension with and without diabetes or dyslipidaemia: comparison with normotensives and sustained hypertensives

BACKGROUND: Arterial distensibility can be assessed by measuring pulse-wave velocity (PWV). OBJECTIVE: To determine whether diabetes, smoking and dyslipidaemia were associated with greater than normal stiffness of aortic walls in subjects with white-coat hypertension. METHODS: Arterial distensibility was assessed by automatic measurement of carotid-femoral PWV in 35 healthy normotensives, 46 white-coat hypertensives (WCH, clinic blood pressures >140/90 mm Hg, daytime blood pressures <130/85 mm Hg) and 81 ambulatory hypertensives (clinic blood pressures >140/90 mmHg, daytime blood pressures > or =130 mm Hg systolic or > or =85 mm Hg diastolic, or both) all matched for age, sex and body mass index. Nineteen normotensives (subgroup A), 28 WCH (subgroup A) and 37 ambulatory hypertensives (subgroup A) had only one or no other major cardiovascular risk factor whereas 16 normotensives (subgroup B), 18 WCH (subgroup B) and 44 ambulatory hypertensives (subgroup B) had also some combination of non-insulin-dependent diabetes, a smoking habit and dyslipidaemia. RESULTS: Both for the WCH and for ambulatory hypertensives diabetes and dyslipidaemia (subgroups B) were associated with higher (P<0.04) PWV (11.6+/-0.3 and 12.8+/-0.3m/s, respectively) than for subgroups A (9.3+/-0.5 and 10.9+/-0.6 m/s, respectively). In contrast, PWV for WCH in subgroup A (9.3+/-0.5m/s) did not differ (P>0.35) from those for the normotensive subgroups A (9.2+/-0.3m/s) and B (9.6+/-0.4m/s). PWV was not correlated to levels of glycaemia, glycosylated haemoglobin and cholesterolaemia. CONCLUSIONS: These results suggest that, both for ambulatory hypertensives and for WCH, diabetes and dyslipidaemia are associated with an impairment of arterial distensibility that can entail a greater than normal cardiovascular risk, which might dictate a more than usually stringent treatment of concomitant risk factors and possibly of high blood pressure. In contrast, PWV in WCH of the subgroup A did not differ from those in normotensives, reinforcing the hypothesis that WCH is associated with a benign cardiovascular outcome in the absence of other cardiovascular risk factors.     

Silent and clinically overt stroke in older Japanese subjects with white-coat and sustained hypertension

BACKGROUND: Whether white-coat hypertension in older subjects is a benign condition or is associated with an increased risk for stroke remains uncertain. White-coat hypertension as a risk factor for stroke was investigated in relation to silent cerebral infarct in the older Japanese population. METHODS: The prognosis for stroke was studied in 958 older Japanese subjects [147 normotensives (NT), 236 white-coat hypertensives (WCHT), and 575 sustained hypertensives (SHT)] in whom ambulatory blood pressure monitoring was performed in the absence of antihypertensive treatment. Silent cerebral infarct was also assessed using brain magnetic resonance imaging in 585 subjects (61%). RESULTS: Silent cerebral infarcts were found in 36% of NT (n = 70), 42% of WCHT (n = 154), and 53% of SHT (n = 361), and multiple silent cerebral infarcts(presence of > or = 2 silent cerebral infarcts) were found in 24% of NT, 25% of WCHT, and 39% of SHT. During a mean 42-month-follow-up period, clinically overt strokes occurred in 62 subjects [NT 3(2.0%), WCHT 5(2.1%), SHT 54(9.4%)], with 14 fatal cases [NT 1(0.7%), WCHT 0(0%), SHT 13 (2.3%)]. Cox regression analysis showed that age (p = 0.0001) and SHT [RR(95% confidence interval): 4.3 (1.3-14.2), p = 0.018] were independent stroke predictors, whereas WCHT was not significant. Adding presence/absence of silent cerebral infarct at baseline into this model, the RR (95% confidence interval) for silent cerebral infarct was 4.6 (2.0-10.5) (p = 0.003), and that of SHT was 5.5 (1.8-18.9) vs WCHT (p = 0.004) and 3.8 (0.88-16.7) vs NT (p = 0.07). CONCLUSIONS: The incidence of stroke in WCHT is similar to that of NT, and one fourth the risk in SHT in older subjects. Although silent cerebral infarct is a strong predictor of stroke, the difference in stroke prognosis between SHT and WCHT was independent of silent cerebral infarct. It is clinically important to distinguish WCHT from SHT even after assessment of target organ damage in the elderly.     

Factors influencing white-coat effect

BACKGROUND: The transient blood pressure (BP) rise during clinical visits is usually referred to as white-coat effect (WCE). The aim of the present study was to investigate factors that may influence the WCE. METHODS: A total of 2004 subjects underwent office BP measurements and 24-h ambulatory BP monitoring (ABPM) on the same day. The WCE was estimated as the difference between office and average daytime ambulatory BP (ABP). According to the office and daytime BP values, the study population was divided into normotensives (NTs), white-coat hypertensives (WCHs), masked hypertensives (MHTs), and sustained hypertensives (SHTs). Statistical analyses were performed using one-way analysis of variance and multiple linear regression models. RESULTS: The mean systolic and diastolic WCE was 9 +/- 16 and 7 +/- 12 mm Hg, respectively. In the entire group of patients, multiple linear regression models revealed independent determinants of systolic WCE in the following rank order: office systolic BP (SBP) (beta = 0.727; P < 0.001), female gender (beta = 0.166; P < 0.001), daytime SBP variability (beta = 0.128; P < 0.001), age (beta = 0.039, P = 0.020), and smoking (beta = 0.031, P = 0.048). A 1.0 mm Hg increase in daytime SBP variability correlated with an increment of 0.589 mm Hg (95% confidence intervals, 0.437-0.741) in the systolic WCE. The regression analyses for diastolic WCE revealed the same factors as independent determinants. A 1.0 mm Hg increase in daytime diastolic BP (DBP) variability was independently associated with an increment of 0.418 mm Hg (95% confidence intervals, 0.121-0.715) in the diastolic WCE. CONCLUSIONS: Factors such as gender, age, smoking, office BPV and daytime BPV may exert an important influence on the magnitude of the WCE.     

Subclinical arterial damage in untreated masked hypertensive subjects detected by home blood pressure measurement

BACKGROUND: Masked hypertension (MHT: normal office blood pressure [BP] + elevated BP out of the office) is a significant predictor of target organ damage and cardiovascular disease. The purpose of this study was to investigate the subclinical arterial damage in unmedicated subjects with MHT detected by home BP measurement. METHODS: We recruited 282 subjects not taking antihypertensive medication, who had at least one of the following five cardiovascular risk factors: high BP, hyperlipidemia, diabetes mellitus, current smoking, and chronic kidney disease. Furthermore, we classified them into four groups (normotension [NT], white-coat hypertension [WCHT], MHT, and sustained hypertension [SHT]) by office BP (140/90 mm Hg) and home BP (135/85 mm Hg) measurements. Arterial damage was evaluated by measuring carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV). RESULTS: Subjects with MHT had a higher prevalence of habitual alcohol drinkers than the other groups, and higher pulse rates at home than those with NT and WCHT. After adjustment for covariates, carotid IMT was the highest in MHT among the four groups (mean: 1.01 v 0.83 mm for NT, 0.86 mm for WCHT, and 0.91 mm for SHT, all P < .01). The baPWV was also significantly higher in MHT than NT and WCHT (mean: 1940 v 1663 and 1733 cm/sec, all P < .01), whereas the difference between MHT and SHT (2023 cm/sec) was not significant. CONCLUSIONS: This study shows that masked hypertensives detected by home BP are at higher risk for increased arterial damage than normotensives or white-coat hypertensives, and potentially than sustained hypertensives.     

White coat effect in treated and untreated patients with high office blood pressure. Relationship with pulse wave velocity and left ventricular mass index.

OBJECTIVE: To evaluate in hypertensive patients whether the white coat effect is associated with target-organ damage and whether it is modified by anti-hypertensive therapy. METHODS: In a cross-sectional study we evaluated blood pressure (BP) measured in the office and by 24-h ambulatory blood pressure monitoring (ABPM), carotid-femoral pulse wave velocity (PWV) as an index of aortic stiffness, and left ventricular mass index (LVMI) in 88 subjects (aged 49 +/- 2 years) with white-coat hypertension (WCH, office BP > 140/90, daytime BP < 130/84 mmHg), 31 under antihypertensive therapy, 57 untreated, and in 115 patients with office and ambulatory hypertension (HT, aged 51 +/- 2 years, office BP > 140/90, daytime BP > 135/85), 65 under antihypertensive therapy, 50 untreated. In a longitudinal study in 15 patients with HT and in 11 patients with WCH we evaluated the influence of antihypertensive therapy (> 6 months) on office and ambulatory BP and on PWV. RESULTS: The intensity of the white coat effect (office BP-daytime BP) was greater in WCH than in HT. Taking all subjects, the white coat effect did not correlate with PWV (r = 0.08, ns) or with LVMI (r = 0.01, ns), whereas daytime BP correlated significantly with PWV (r = 0.41, p < 0.01) and with LVMI (r = 0.32, p < 0.05). WCH subjects showed lower PWV and LVMI than HT subjects. Treated and untreated WCH, with similar office and daytime BP, showed similar values of PWV and LVMI. Treated and untreated HT showed similar office BP values but treated HT showed lower daytime BP and PWV values. In the longitudinal study, antihypertensive therapy significantly reduced daytime BP and PWV values in the 15 HTs, whereas in the 11 WCH it did not alter daytime BP or PWV values. CONCLUSIONS: 1. In both WCH and HT (treated and untreated) the intensity of the white coat effect does not reflect either the severity of hypertension measured by target organ damage or the efficacy of antihypertensive treatment. 2. In WCH antihypertensive therapy does not improve either ambulatory BP values or damage to target organs.     

Silent and clinically overt stroke in older Japanese subjects with white-coat and sustained hypertension.

OBJECTIVES: We investigated whether white-coat hypertension is a risk factor for stroke in relation to silent cerebral infarct (SCI) in an older Japanese population. BACKGROUND: It remains uncertain whether white-coat hypertension in older subjects is a benign condition or is associated with an increased risk of stroke. METHODS: We studied the prognosis for stroke in 958 older Japanese subjects (147 normotensives [NT], 236 white-coat hypertensives [WCHT] and 575 sustained hypertensives [SHT]) in whom ambulatory blood pressure monitoring was performed in the absence of antihypertensive treatment. In 585 subjects (61%), we also assessed SCI using brain magnetic resonance imaging. RESULTS: Silent cerebral infarcts were found in 36% of NT (n = 70), 42% of WCHT (n = 154), and 53% of SHT (n = 361); multiple SCIs (the presence of > or =2 SCIs) were found in 24% of NT, 25% of WCHT and 39% of SHT. During a mean 42-month follow-up period, clinically overt strokes occurred in 62 subjects (NT: three [2.0%]; WCHT: five [2.1%]; SHT: 54 [9.4%]), with 14 fatal cases (NT: one [0.7%]; WCHT: 0 [0%]; SHT: 13 [2.3%]). A Cox regression analysis showed that age (p = 0.0001) and SHT (relative risk, [RR] [95% confidence interval, CI]: 4.3 [1.3-14.2], p = 0.018) were independent stroke predictors, whereas WCHT was not significant. When we added presence/absence of SCI at baseline into this model, the RR (95% CI) for SCI was 4.6 (2.0-10.5) (p = 0.003) and that of SHT was 5.5 (1.8-18.9) versus WCHT (p = 0.004) and 3.8 (0.88-16.7) versus NT (p = 0.07). CONCLUSIONS: In older subjects the incidence of stroke in WCHT is similar to that of NT and one-fourth the risk in SHT. Although SCI is a strong predictor of stroke, the difference in stroke prognosis between SHT and WCHT was independent of SCI. It is clinically important to distinguish WCHT from SHT even after assessment of target organ damage in the elderly.     

Determinants of the white-coat effect in normotensives and never-treated mild hypertensives

The prognostic significance of the white-coat effect (WCE) is unclear. Knowledge of the predictors of the WCE may help illuminate the clinical significance of this phenomenon. The purpose of this study was to (i) compare characteristics of subjects demonstrating a WCE, those not demonstrating a WCE, and those demonstrating a reverse WCE and (ii) determine clinical features that may influence the size of the WCE. Forty-one subjects with normotension or mild hypertension who had never been treated with antihypertensive medications were recruited for the study. All subjects underwent a battery of anthropometrical measurements and clinic blood pressure (BP) measurements. To calculate arterial compliance, impedance cardiography was used to measure resting stroke volume in each subject. All subjects performed a laboratory mental stress protocol to determine the size of the BP reactivity. Ambulatory blood pressure (ABP) profiles were studied in each subject with the use of an oscillometric ABP recorder. White-coat effect was determined by subtracting the awake period of the ambulatory systolic blood pressure (SBP) from the clinical SBP. Subjects were grouped according to the size of their WCE. Those who showed a WCE of 5 mmHg and above were assigned to the WCE group; those who showed a WCE of between -5 and 5 mmHg were assigned to the no white coat effect (NWCE) group; those who exhibited a WCE of -5 mmHg and lower were assigned to the reverse white-coat effect (RWCE) group. Subjects with a positive WCE had significantly higher body mass index (BMI) than those without a WCE and those with a RWCE. The WCE group had significantly higher clinic SBP and heart rate (HR) than the RWCE group. Arterial compliance was significantly lower in the WCE group as compared to the NWCE group and the RWCE group. The three groups had comparable ABP profiles. In terms of BP variability, the increase in SBP in response to mental stress did not differ among the three study groups nor did the 24-hour and awake BP variability. For the sample as a whole, clinic HR and clinic-ambulatory SBP difference were higher and arterial compliance were lower in women than in men. Furthermore, clinic SBP significantly correlated with the systolic WCE (r = 0.40, P = 0.009). When men and women were analyzed separately, the correlation between clinic SBP and the systolic WCE was significant in women (r = 0.63, P = 0.001) but not in men (P = 0.95). Multiple linear regression showed that sex (P = 0.013) and clinical SBP (P = 0.003) were the only two variables that significantly influenced the systolic WCE. These two variables together accounted for 29% of the variation in the systolic WCE. In conclusion sex and clinic BP are two major determinants of the WCE. The results of this study indicate that WCE is not related to higher stress reactivity or higher BP variability.     

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.     

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.     

Masked hypertensives: A disguised arterial stiffness population

The aim of this study was to determine whether masked hypertension (MHT) and white coat hypertension (WCHT) could be related to increased arterial stiffness and to identify the best office cutoff values of office BP for the diagnosis of MHT and WCHT. A total of 542 consecutive patients (50.2% male, age 42.5 ± 26.2 years) were included in the study. Patients were never treated before for hypertension. Patients were classified as true normotensives (44%), true hypertensives (30%), WC hypertensives (19%), and masked hypertensives (7%). Carotid‐femoral pulse wave velocity (c‐f PWV) was 9.91 ± 0.20 m/s in true normotension, 10.26 ± 0.27 m/s in WCHT, 11.28 ± 0.47 m/s in MHT, and 11.86 ± 0.23 m/s in true hypertension after adjustment for age and sex. Decision limits yielding 65% sensitivity were 130 mm Hg for office systolic BP with 72% specificity for the diagnosis of MHT. The optimal cutoff value of 80 mm Hg for office diastolic BP provides 60% sensitivity and 68% specificity. Decision limits yielding 63% sensitivity were 150 mm Hg for office systolic BP with 72% specificity for the diagnosis of WCHT. The optimal cutoff value of 95 mm Hg for office diastolic BP provides 75% sensitivity and 51% specificity. The presence of MHT should be taken into account when increased c‐f PWV is detected in the absence of office hypertension. The optimal office BP of 130/80 mm Hg provides the best sensitivity and specificity for the diagnosis of MHT. As regards the diagnosis of WCHT, the cutoff value of 150/95 mm Hg seems to provide the best option.     

Cardiovascular risk in white-coat and sustained hypertensive patients

We compared cardiovascular outcome between patients with white-coat and sustained hypertension who had previously participated in the Ambulatory Blood Pressure Monitoring and Treatment of Hypertension (APTH) trial. Baseline characteristics, including office and ambulatory blood pressure (BP), were measured during the 2-month run-in period of the APTH trial. During follow-up, information on the occurrence of major cardiovascular events (death, myocardial infarction, stroke and heart failure), achieved office BP and treatment status was obtained. At entry, 326 patients had sustained hypertension (daytime ambulatory BP ≥140 mmHg systolic and/or ≥90 mmHg diastolic) and 93 had daytime ambulatory BP below these limits and were classified as white-coat hypertensives. During 2088 patientyears of follow-up (median follow-up 5.3 years), all major cardiovascular events ( n = 22) occurred in the patients with sustained hypertension (rate 12.7 per 1000 patient-years, p = 0.02 for between-group difference). Furthermore, multiple Cox regression confirmed that after adjustment for important covariables, daytime ambulatory BP - but not office BP at entry - significantly and independently predicted cardiovascular outcome. After additional adjustment for office BP, daytime ambulatory BP still predicted the occurrence of major cardiovascular events. Although white-coat hypertension was less frequently associated with antihypertensive drug treatment during follow-up, it carried a significantly better prognosis than sustained hypertension.     

Ambulatory blood pressure in the young adult with hypertension history during childhood]

The tendency of subjects to maintain their relative position within the distribution of blood pressure (BP) has been defined as "tracking". Regarding this phenomenon, the purpose of the study was to evaluate the interest of ambulatory BP monitoring (ABPM) in the assessment of arterial hypertension in young adults (YA) with childhood hypertension history (CHH). 52 subjects, 20.1 +/- 2.4 years old, 26 men, 26 women issued from a cohort of 150 children with high BP levels (greater than 97.5 th percentile) during their infancy (school check-up), were included in the study. An ABPM was performed with space-labs system 90202 from 8 a.m. to 6 p.m., measurements every 15 minutes (37.6 +/- 7.4 readings). Left ventricular mass index (LVMI) was determined with echocardiography, (Penn convention). Office BP, measured with mercury apparatus in lying and standing position, was respectively, 131.0 +/- 14.6/81.9 +/- 9.7 and 130.1 +/- 14/86.6 +/- 9.9. According to JNC 1988, this casual BP identified 40 normotensives (NT), 9 borderlines (BL) and 5 hypertensives (HT); 10 of them had a "high normal" diastolic BP (85-90 mmHg) ABP recordings of the study group were compared to day-time reference values of NT. Three subgroups are individualized: G1 NT, G2 HT, G3 BL. [table; see text] *p: less than 0.001; p: less than 0.01. Wall thickness (WTh) and LVMI were significantly higher in hypertensives (G2 + G3) than in normotensives (G1): [table; see text] There was a significant correlation between LVMI and mean systolic ABP (p less than 0.01: r = 0.44), but not with office SBP.(ABSTRACT TRUNCATED AT 250 WORDS)     

Predictors of controlled ambulatory blood pressure in treated hypertensive patients with uncontrolled office blood pressure.

Although some treated hypertensive patients have controlled 24-h ambulatory blood pressure (ABP) despite their uncontrolled office blood pressure (BP), the factors relating to the control of 24-h ABP remain unknown. We conducted a study to assess 24-h ABP and its association with other cardiovascular risk factors, including echocardiographic left ventricular hypertrophy (LVH), in elderly hypertensive patients (n =41) with uncontrolled office BP (>140/90 mmHg) during long-term medication. Although a majority of the patients had isolated elevation of office systolic BP (SBP), there was no significant relationship between office SBP and 24-h SBP, and about half of the patients had controlled 24-h ABP (125+/-8/69+/-6 mmHg). Patients with controlled 24-h ABP (125+/-8/69+/-6 mmHg) had similar office BP (150+/-6/77+/-5 vs. 150+/-7/79+/-7 mmHg), but lower left ventricular mass index (LVMI) (123+/-34 vs. 156+/-34 g/m(2)) and body mass index (BMI) (24.4+/-2.1 vs. 26.4+/-3.6 kg/m(2)) compared with those with uncontrolled 24-h ABP (149+/-13/78+/-7 mmHg). Multivariate analysis showed that LVMI and BMI were independently associated with controlled 24-h ABP, and the control status of 24-h ABP was highly dependent on the presence of LVH and obesity. Therefore, absence of LVH and obesity may be useful for predicting the level of control of 24-h ABP in treated patients whose office BP is uncontrolled without ABP measurements.     

Sequential follow-up clinic and ambulatory blood pressure evaluation in a low risk population of white-coat hypertensive patients and in normotensives

BACKGROUND: In subjects with white-coat hypertension (WCH) it is unclear how ambulatory blood pressure (ABPM) progresses over time and whether they exhibit an increased cardiovascular risk. METHODS: We prospectively evaluated the transition of clinic and ABPM values in 39 clinic and ABPM normotensive subjects (NT) (clinic BP<140/90 mmHg and awake BP<130/85 mmHg, ages 43.4+/-2.6 y) and in 79 untreated subjects (47.2+/-2.4 y) with WCH (clinic BP>140/90, awake ABP<130/85 mmHg) with no other major cardiovascular risk factors. Ambulatory blood pressure was evaluated at baseline and on at least two further occasions during follow-up. RESULTS: At baseline all subjects were untreated and groups did not differ on values of metabolic parameters, BMI, left ventricular mass index, and ABPM values. Subjects were revaluated for ABPM half way through and at the end of follow-up, 35+/-3 and 86+/-4 months in NT and 49+/-4 and 90+/-4 months in WCH. Thirty-six WCH were on antihypertensive treatment (AH) after baseline until the end of follow-up (WCH-tr), whereas 43 WCH (WCH-untr) were free from AH throughout the study. In a similar way all groups showed a significant (p<0.01) progressive increase in 24-h ABPM systolic blood pressure (SBP)/diastolic blood pressure (DBP) from baseline throughout the follow-up in NT (+4.9/2.1+/-0.8/0.9 mmHg), average annual increase of 0.72/0.37 mmHg/y, in WCH-tr (+ 5.0/1.2+/-1.1/1.5 mmHg), average annual increase of 0.66/0.31 mmHg/y and in WCH-untr (+5.4/3.2+/-0.9/1.1 mmHg), average annual increase of 0.74/0.39 mmHg/y. During the follow-up office SBP/DBP (mmHg) significantly rose in NT (+5.7/3.9) but was reduced in WCH-tr (-7.8/5.2) and in WCH-untr (-4.7/1.1). Development of ambulatory hypertension (daytime BP >130 and/or >85 mmHg) occurred in 15.4% (6/39) of NT, in 22.7% (8/36) of WCH-tr and in 26.1% (11/43) of WCH-untr (NS). First cardiovascular events recorded were three in subjects with WCH and none in NT. CONCLUSIONS: After 7.4 years of follow-up, both the progressive increase in ABPM and the rate of transition to ambulatory hypertension in subjects with WCH (either treated or untreated), who were selected under strict criteria were similar to that of normotensive subjects. Also there was no evidence that WCH exhibited a clear higher risk of development cardiovascular events.     

Prognosis of "masked" hypertension and "white-coat" hypertension detected by 24-h ambulatory blood pressure monitoring 10-year follow-up from the Ohasama study

OBJECTIVES: We sought to investigate the prognosis in subjects with "white-coat" hypertension (WCHT) and "masked" hypertension (MHT), in which blood pressure (BP) is lower in clinical measurements than during ambulatory monitoring. BACKGROUND: The prognostic significance of WCHT remains controversial, and little is known about MHT. METHODS: We obtained 24-h ambulatory BP and "casual" BP (i.e., obtained in clinical scenarios) values from 1,332 subjects (872 women, 460 men) > or =40 years old in a representative sample of the general population of a Japanese community. Survival and stroke morbidity were then followed up for a mean duration of 10 years. RESULTS: Composite risk of cardiovascular mortality and stroke morbidity examined using a Cox proportional hazards regression model for subjects with WCHT (casual BP > or =140/90 mm Hg, daytime BP <135/85 mm Hg; relative hazards [RH])1.28; 95% confidence interval [CI] 0.76 to 2.14) was no different from risk for subjects with sustained normal BP (casual BP <140/90 mm Hg, daytime BP <135/85 mm Hg). However, risk was significantly higher for subjects with MHT (casual BP <140/90 mm Hg, daytime BP > or =135/85 mm Hg; RH 2.13; 95% CI 1.38 to 3.29) or sustained hypertension (casual BP > or =140/90 mm Hg, daytime BP > or =135/85 mm Hg; RH 2.26; 95% CI 1.49 to 3.41) than for subjects with sustained normal BP. Similar findings were observed for cardiovascular mortality and stroke morbidity among subgroups by gender, use of antihypertensive medication, and risk factor level (all p for heterogeneity >0.2). CONCLUSIONS: Conventional BP measurements may not identify some individuals at high or low risk, but these people may be identifiable by the use of ambulatory BP.     

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.     

Associations between nondipping of nocturnal blood pressure decrease and cardiovascular target organ damage in strictly selected community-dwelling normotensives

BACKGROUND: In hypertensives, nondippers are more likely than dippers to suffer silent, as well as overt, hypertensive target organ damage. In this study, we investigated whether a nondipper status was associated with target organ damage in normotensives. METHODS: We performed ambulatory blood pressure (BP) monitoring, echocardiography, and carotid ultrasonography and measured natriuretic peptides and urinary albumin (UAE) in 74 normotensive subjects with the following criteria: 1) clinical BP <140/90 mm Hg; 2) average 24-h ambulatory BP <125/80 mm Hg. RESULTS: The left ventricular mass index (LVMI) and the relative wall thickness (RWT) measured by echocardiography were greater in nondippers than dippers (LVMI: 103 +/- 26 v 118 +/- 34 g/m(2), P <.05; RWT: 0.38 +/- 0.07 v 0.43 +/- 0.09, P <.01). Plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were higher in nondippers than dippers (ANP: 14 +/- 10 v 36 +/- 63 pg/mL, P <.01; BNP: 16 +/- 12 v 62 +/- 153 pg/mL, P <.05). There were no significant differences in UAE and intima-media thickness measured by carotid ultrasonography. CONCLUSIONS: Normotensive nondipping may not reflect renal damage, but may have a predominant effect on cardiac damage. Nondipping of nocturnal BP seems to be a determinant of cardiac hypertrophy and remodeling, and may result in a cardiovascular risk independent of ambulatory BP levels in normotensives.     

The clinical significance of white-coat and masked hypertension

OBJECTIVE: Self-measured blood pressure (BP) and 24-hour ambulatory blood pressure (ABP) monitoring are used to define the arbitrary clinical categories of masked hypertension (MH) and white-coat hypertension (WCH). Severity of target organ damage and incidence of major cardiovascular events are greater in patients with MH than in patients whose BP is normal both inside and outside the doctor's office. METHODS: We reviewed studies that addressed the prognostic impact of MH and WCH. RESULTS: Overall, WCH was associated with a better outcome and MH to a poor outcome. We, however, need the criteria to identify the clinically normotensive patients at elevated pretest probability of MH in whom a broad use of self-measured home BP and 24-hour ambulatory BP as screening tests may be appropriate and cost effective. Clinical management of patients with MH should continue to be based on current guidelines and mostly related to target organ damage and associated clinical conditions because of the normal values of clinic BP in these patients. WCH is generally defined by the coexistence of persistently high office BP with normal daytime or 24-hour ABP. Daytime ABP normalcy has been defined by values<135/85 mmHg. Data, however, suggest that incidence of cardiovascular events tends to increase consistently above the cut-off value of 130/80 mmHg for daytime BP. CONCLUSION: The long-term outcome of patients with WCH remains uncertain. Data suggesting an increased risk of stroke need to be confirmed in wide-scale studies.     

Incidence of cardiovascular events in white-coat, masked and sustained hypertension versus true normotension: a meta-analysis

OBJECTIVE: To perform a meta-analysis on the incidence of cardiovascular events in white-coat hypertension (WCHT), masked and sustained hypertension in comparison with true normotension. METHODS: We searched for individual studies, in which the adjusted relative risk of incident cardiovascular events was assessed in patients with WCHT, masked and sustained hypertension versus normotension in the same study population. For each type of hypertension, the weighted overall hazard ratio (HR) and 95% confidence intervals (CI) were calculated. RESULTS: Seven studies were identified, involving a total of 11 502 participants. Four studies were performed in the population, two in primary care and one in specialist care. Two studies were exclusively on treated hypertensive patients; individuals on antihypertensive treatment were included in all the other studies except one. Cut-off blood pressure was 140/90 mmHg for office blood pressure in all studies and 135/85 mmHg (83 in one study) for out-of-office blood pressure. The average age of the study populations was 63 years; 53% were men. The endpoint consisted of cardiovascular death in one study and of various aggregates of fatal and non-fatal cardiovascular events in the others. During an average follow-up of 8.0 years, there were 912 first cardiovascular events. The overall adjusted HR versus normotension was 1.12 (95% CI 0.84-1.50) for WCHT (P = 0.59), 2.00 (1.58-2.52) for masked hypertension (P < 0.001), and 2.28 (1.87-2.78) for sustained hypertension (P < 0.001). CONCLUSION: The meta-analysis indicates that the incidence of cardiovascular events is not significantly different between WCHT and true normotension, whereas the outcome is worse in patients with masked or sustained hypertension.