Relationship of circadian blood pressure and morning blood pressure surge with the severity of metabolic syndrome in newly diagnosed hypertensives.

OBJECTIVES: Twenty-four-hour ambulatory blood pressure (BP) data and the presence of metabolic syndrome (MS) are both good discriminators of cardiovascular risk. We examined the relationship between metabolic syndrome scores as defined by the International Diabetes Federation 2005 report (IDF-2005) and 24h ambulatory BP data in newly diagnosed hypertensives. METHODS: We evaluated 352 non-diabetic subjects (male/female: 167/185, aged 49+/-13). Based on IDF-2005 criteria, 212 subjects fulfilled 0, 1 or 2 criteria (no metabolic syndrome) and 140 fulfilled 3, 4 or 5 criteria (metabolic syndrome). Patients were divided into two groups (MS and non-MS), matched for age and casual BP All underwent 24h ambulatory blood pressure monitoring. RESULTS: No significant differences were found between non-MS and MS for casual BP (153/92+/-17/8 vs. 154/92+/-16/8 mmHg), age (48+/-14 vs. 50+/-12 years), 24h ambulatory BP (131/82+/-14/10 vs. 133/82+/-14/9 mmHg), daytime BP (135/86+/-14/11 vs. 137/85+/-14/9 mmHg), nighttime BP (122/74+/-15/11 vs. 124/74+/-15/10 mmHg), nighttime fall (9+/-6 vs. 9+/-6 %), BP on arising (131/82+/-20/15 vs. 135/82+/-21/15 mmHg), evening surge (7+/-14 vs. 10+/-15 mmHg), percentage of dippers (42.5 vs. 37.1%) or percentage of non-dippers (50.9 vs. 50.7%). However, significant differences between non-MS and MS were found for morning BP surge (25+/-12 vs. 28+/-15 mmHg, p<0.03). Also, when patients were divided into four groups according to MS scores (0/1, 2, 3 or 4/5), significant differences between groups were observed only for BP on arising (group 2 vs. 4/5, 132/79+/-21/15 vs. 140/84+/-10/15 mmHg, p<0.05; group 3 vs. 4/5, 131/81+/-20/15 vs. 140/84+/-20/15, p<0.005) and for morning BP surge (group 0/1 vs. 4/5, 24+/-11 vs. 29+/-15 mmHg, p<0.003). CONCLUSIONS: We conclude that in newly diagnosed hypertensive subjects there is no significant relationship between the severity of metabolic syndrome and ambulatory blood pressure data or circadian variations. The only exception found was a greater morning BP surge in patients with MS, whose importance as a determinant of cardiovascular risk needs to be clarified by further studies.     

Relationship between aortic stiffness and cardiovascular risk factors in a population of normotensives, white-coat normotensives, white-coat hypertensives, sustained hypertensives and diabetic patients.

OBJECTIVE: To evaluate the relationship between carotid-femoral pulse wave velocity (PWV) and office and ambulatory blood pressure (ABP) and other cardiovascular risk factors and to determine the discriminatory value of PWV in a large population including normotensive subjects (NT), white-coat normotensives (masked hypertension) (WCNT), and white-coat hypertensives (WCHT) compared to a group of treated and untreated hypertensive patients. METHODS: The study population included a total of 688 subjects aged from 18 to 80 years, with no previous cardiovascular events, who underwent 24 h ABP monitoring, biochemical evaluation and determination of PWV and left ventricular mass index (LVMI). Subjects were classified as true normotensives (NT, n=132; normal office and ABP values), WCNT (n=39; office BP < 140/90 and daytime BP > or =135 or > or =85 mmHg), WCHT (n=87; office BP > or =140 or > or =90 and daytime BP < 135/85 mmHg). Untreated (UT-HT, n=154) and treated (T-HT, n=171) hypertensive patients and type 2 diabetic patients (DM, n=102) were also studied. RESULTS: Values of PWV (m/s) in all groups were, in ascending order: NT (8.9 +/- 0.2) < WCHT (9.9 +/- 0.2) < T-HT (11.4 +/- 0.2) = WCNT (11.5 +/- 0.4) < UT-HT (11.9 +/- 0.3) < DM (12.6 +/- 0.4) (ANOVA, p = 0.043), and of LVMI (g/m2): NT (59 +/- 2) = WCHT (63 +/- 2) < WCNT (73 +/- 3) = T-HT (75 +/- 3) = UT-HT (77 +/- 3) < DM (84 +/- 4) (ANOVA, p < 0.05). The percentage of subjects with PWV values below the median (10.7 m/s) was higher (p < 0.02) in NT (81.8%) and WCHT (72.6%) than in UT-HT (49.2%), T-HT (43.6%), WCNT (47.6%) and DM (27.7%). In multiple regression analysis, taking PWV as the dependent variable, age (all groups), 24h systolic BP (UT-HT, T-HT, WCNT and DM) and 24h diastolic BP (NT and WCHT) were the variables that independently influenced the PWV value. CONCLUSIONS: Higher values of PWV occur in clinical situations associated with higher cardiovascular risk. This is in agreement with risk stratification based on ABP values but not on office BP values. Lower PWV and LVMI values occur in NT and WCHT subjects, supporting a low cardiovascular risk in these groups. By contrast, higher PWV values were associated with higher ABP values in DM, hypertensive patients and white-coat normotensives, i.e. clinical situations that are associated with higher cardiovascular risk, who in the present study also exhibited higher LVMI than subjects with normal ABP values.     

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)     

Twenty-four hour ambulatory blood pressure in a population of elderly men

OBJECTIVES: The principal aim was to study ambulatory and office blood pressure in a population of elderly men. We also wanted to describe the prevalence of hypertension and investigate the blood pressure control in treated elderly hypertensives. DESIGN: A cross-sectional study of a population of elderly men, conducted between 1991 and 1995. SUBJECTS: Seventy-year-old men (n = 1060), participants of a cohort study that began in 1970. MAIN OUTCOME MEASURES: Office and 24 h ambulatory blood pressure. RESULTS: Average 24 h blood pressure in the population was 133 +/- 16/75 +/- 8 mmHg, and daytime blood pressure 140 +/- 16/80 +/- 9 mmHg. Corresponding values in untreated subjects (n = 685) were 131 +/- 16/74 +/- 7 and 139 +/- 16/79 +/- 8, respectively. An office recording of 140/90 mmHg corresponded to an ambulatory pressure of 130/78 (24 h) and 137/83 mmHg (daytime) in untreated subjects. In subjects identified as normotensives according to office blood pressure (n = 270), the 95th percentiles of average 24 h and daytime blood pressures were 142/80 and 153/85 mmHg, respectively. The prevalence of hypertension, defined as office blood pressure greater than or = 140/90 mmHg, was 66%. Despite treatment, treated hypertensives (n = 285) showed higher office (157/89 vs. 127/76 mmHg) and 24 h ambulatory (138/78 vs. 122/71 mmHg) pressures than normotensives (P < 0.05). Fourteen per cent of the treated hypertensives had an office blood pressure < 140/90 mmHg. CONCLUSIONS: Our results provide a basis for 24 h ambulatory blood pressure reference values in elderly men. The study confirms previous findings of a high prevalence of hypertension at older age. It also indicates that blood pressure is inadequately controlled in elderly treated hypertensives.     

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.     

Serum testosterone levels and arterial blood pressure in the elderly.

The aim of this study was to evaluate the relationship between serum testosterone levels and arterial blood pressure (BP) in the elderly. We studied 356 non-diabetic, non-smoking, non-obese men aged 60 to 80 years and untreated for hypertension. All subjects were evaluated in the morning after an overnight fast. Evaluation included measurements of the following: BP (by mercury sphygmomanometer, Korotkoff I and V), body weight, height and free testosterone (T) plasma levels (by radioimmunoassay). According to the BP values, the subjects were classified as normotensives (NT; n=112; SBP/DBP<140/90 mmHg), systolic and diastolic hypertensives (HT; n=127; SBP/DBP>140/90 mmHg), and isolated systolic hypertensives (ISH; n=117; SBP>140 mmHg and DBP<90 mmHg). T values decreased with increasing age in all 3 groups and was significantly lower in HT (-15%) and ISH men (-21%) than in NT men (p<0.05). In each group, the T levels showed a highly significant negative correlation with BMI (p<0.001). A significant negative correlation was also found between T levels and SBP in NT (r=-0.35, p<0.001), ISH (r=-0.67, p<0.001), and HT (r=-0.19, p<0.05) men, whereas a negative correlation with DBP was observed only in the NT men (r=-0.19, p<0.05). Adjusting for the BMI confirmed a significant difference in plasma T levels between ISH and NT men, but not between HT and NT men. Multiple regression analysis employing BP as a dependent variable confirmed a strong relationship between T levels and SBP in all 3 groups, whereas a significant relationship between T levels and DBP was found only in NT men. In conclusion, although further studies are needed to clarify the relationship between plasma T levels and BP, our findings suggest that in elderly men with ISH, the reduced plasma levels of testosterone might contribute to the increased arterial stiffness typical of these subjects.     

Ambulatory blood pressure variability is increased in diabetic hypertensives

The purpose of this study was to examine the possible difference in the 24-hr BP profile--including short-term BP variability, assessed as the standard deviation--between diabetic and non-diabetic hypertensives. We measured 24-hr ambulatory BP in 11 diabetic hypertensives (diabetic HT) and 10 non-diabetic hypertensives (non-diabetic HT) who were hospitalized for the educational program in our hospital and were under stable salt intake. Renal function and sleep apnea were also estimated. There were no significant differences in 24-hr systolic BP (141 mmHg vs. 135 mmHg, ns), daytime systolic BP (143 mmHg vs. 138 mmHg, ns), and nighttime systolic BP (135 mmHg vs. 130 mmHg, ns) between diabetic HT and non-diabetic HT. The values of 24-hr HR (69.7 beats/min vs. 65.2 beats/min, ns) and 24-hr HR variability (9.9 beats/min vs. 10.1 beats/min, ns) were also similar between the groups. Interestingly, diabetic HT had a significantly greater 24-hr systolic and diastolic BP variability than non-diabetic HT (18.2 mmHg vs. 14.5 mmHg, p < 0.05; 11.5 mmHg vs. 9.6 mmHg, p < 0.05, respectively). The values for creatinine clearance, urinary protein excretion, and apnea-hypopnea index were similar between the groups. Bivariate linear regression analysis demonstrated that fasting blood glucose was the primary determinant of 24-hr diastolic BP variability (r = 0.661, p < 0.01). Multiple stepwise regression analysis revealed that fasting blood glucose was a significant and independent contributor to 24-hr systolic BP variability (r = 0.501, p < 0.05). Taken together, these results demonstrate that BP variability is increased in diabetic hypertensives. Furthermore, it is possible that an elevation of fasting blood glucose may contribute to the enhanced BP variability in hypertensives.     

Arterial hypertension increases left ventricular mass: role of tight blood pressure control

In middle-age hypertensives from the Gubbio Population Study, we evaluated the relationship between blood pressure (BP) control over a long time and the prevalence of left ventricular hypertrophy (LVH). A population survey was performed in 1982-1985 and repeated in 1989-1992. During the second survey, subjects in the age range 40-60 years were invited to undergo an M-mode echocardiographic examination. A total of 487 subjects who participated in both surveys are included in the present analysis. Some of them (294) were normotensive (Group 1), 110 were hypertensive but had never taken antihypertensive drugs (Group 2), 47 hypertensives on drugs were in good BP control (Group 3) and 36 hypertensives on drugs had uncontrolled hypertension (Group 4). BP values at the 1989-1992 examination were, respectively, 122/77, 145/86, 124/78 and 153/91 mmHg, while 7 years earlier were 122/77, 133/84, 136/85 and 152/95 mmHg. Despite normal BP levels in Group 3, left ventricular mass index (LVMi, g/m(2.7)) was greater than in normotensives (42.4+/-10, 46.6+/-13, 47.0+/-10, 51.9+/-15 g/m(2.7)). Accordingly, the prevalence of LVH (LVMi >51 g/m(2.7)) was 18, 26.4, 36.7 and 50% in groups 1-4, respectively. The 193 hypertensives were, thereafter, divided according to BP control (ie <140/90 mmHg) on both surveys (1983-1985 and 1989-1992): 27 hypertensives with optimal BP levels on both visits also had a ventricular mass similar to normotensives and significantly lower than the other hypertensives (LVMi 44.6+/-11.6 vs 48.5+/-13.2, P<0.001). In conclusion, these findings indicate that hypertensive patients with BP values at levels similar to those in normotensives for a long period do not increase their left ventricular mass in comparison to subjects with normal BP levels.     

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.     

How does deep breathing affect office blood pressure and pulse rate?

Little is known about the relation between deep breathing (DB) and blood pressure (BP). We studied the relationship between DB and BP in a large Japanese population. The subjects were recruited from randomly selected clinics and hospitals that were members of a medical association, and divided into two groups. In one group, BP was measured before and after taking 6 DB over a period of 30 s, and in the other group BP was measured before and after a 30-s rest in a sitting position without DB. Before these measurements, all patients rested 10 min or more in the waiting room and another 2 min or more in the doctor's office. Analyses were performed on data collected from 21,563 subjects. In both groups, systolic blood pressure (SBP), diastolic blood pressure (DBP) and pulse rate (PR) were significantly reduced after DB or a 30-s rest compared with the baseline measurements (p < 0.001). SBP reductions were greater in the DB group than in the 30-s rest group (normotensives: -6.4 +/- 8.3 vs. -3.0 +/- 7.4 mmHg, p < 0.001; untreated hypertensives: -9.6 +/- 10.2 vs. -5.9 +/- 9.1 mmHg, p < 0.001; treated hypertensives: -8.3 +/- 9.6 vs. -4.4 +/- 8.3 mmHg, p < 0.001). Greater BP reductions were found in patients with a higher baseline BP in both the DB and 30-s rest groups. In conclusion, the present study showed a baseline BP-dependent BP reduction by DB, suggesting that BP measurement should be done without DB in the office because DB lowers BP.     

Status of home blood pressure measured in morning and evening: evaluation in normotensives and hypertensives in Japanese urban population.

To assess home blood pressure status in a Japanese urban population, we analyzed home blood pressure values in normotensive subjects determined by casual blood pressure (< 140/90 mmHg), hypertensive subjects without medication (> or = 140/90 mmHg) and treated hypertensive patients. The subjects (468 male, 232 female; mean age 41 years old) were recruited from a company located in Tokyo. Home blood pressure was measured with a semi-automatic device (Omron HEM-759P). Subjects were instructed to perform triplicate morning and evening measurements on 7 consecutive days. In the treated hypertensive group (n = 70), there was a significant difference between morning (139 +/- 12/88 +/- 9 mmHg) and evening (130 +/- 12/79 +/- 8 mmHg) home blood pressure. In the normotensive group (n = 558), however, only the diastolic blood pressure (DBP) component of the home blood pressure was significantly different between morning (115 +/- 13/72 +/- 9 mmHg) and evening (114 +/- 12/68 +/- 8 mmHg). In the nontreated hypertensive group (n = 72), casual blood pressure (145 +/- 14/92 +/- 9 mmHg) was higher than morning (138 +/- 16/89 +/- 11 mmHg) and evening (134 +/- 16/83 +/- 11 mmHg) home blood pressure, but no difference was seen between morning and evening systolic blood pressure (SBP). According to the reference value of the Japanese Society of Hypertension 2004 (SBP > or = 135 mmHg and/or DBP > or = 85 mmHg), 7.2% (systolic) and 8.7% (diastolic) of subjects in the normotensive group were classified as hypertensive by home blood pressure. Casual blood pressure in the treated hypertensive group was normal in 64.3% for SBP and 70.0% for DBP. However, their morning SBP (32.9%), morning DBP (40.0%), evening SBP (10.0%), and evening DBP (17.1%) were classified as hypertensive by home blood pressure. Furthermore, patients who were taking antihypertensive drug(s) only in the morning (n = 52) showed higher morning SBP (6 mmHg, p = 0.086) and morning DBP (6 mmHg, p = 0.005) than patients taking drug(s) by other administration schedules (n = 18), but no difference in evening home blood pressure was observed. In conclusion, a proportion of the subjects defined as normotensive by casual blood pressure were classified as hypertensive by home blood pressure in the present urban population. Furthermore, morning home blood pressure control in the treated hypertensive group classified as under control by casual blood pressure was insufficient, especially in patients who were taking medication only in the morning.     

Greater change of orthostatic blood pressure is related to silent cerebral infarct and cardiac overload in hypertensive subjects.

Greater change of postural blood pressure (BP) is often seen in elderly hypertensives and is recognized as a risk factor for cognitive decline and poorer cerebrovascular outcome, but its clinical significance still remains to be clarified. We performed a head-up tilting test, ambulatory BP monitoring, and brain MRI in 59 hypertensives and 27 normotensive subjects. We measured plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels at rest to assess cardiac burden. The 59 hypertensive patients were classified into 3 groups: an orthostatic hypertension (OHT) group with orthostatic increase in systolic BP (SBP) > or = 10 mmHg (n=16); an orthostatic hypotension (OHYPO) group with orthostatic SBP decrease < or = -10 mmHg (n=18); and an orthostatic normotension (ONT) group with neither of these two patterns (n=25). A group of 27 normotensive subjects (NT) was also included as a control. Plasma BNP (72 +/- 92 vs. 29 +/- 24 pg/ml, p < 0.05) and BNP/ANP ratio (4.6 +/- 3.3 vs. 2.4 +/- 1.5, p < 0.05) were significantly higher in the OHYPO than in the NT group. The BNP/ANP ratio was also higher in the OHT than in the NT group (5.1 +/- 3.9 vs. 2.4 +/- 1.5, p < 0.01). The number of silent cerebral infarct (SCI), prevalence of SCI and number of multiple SCIs was the highest in the OHT group, followed in order by the OHYPO, ONT and NT groups. Blood pressure and left ventricular mass index were not significantly different among the 3 hypertensive groups. In conclusion, hypertensive patients with greater change of postural BP (OHT and OHYPO) were shown to have increased risk of advanced silent brain lesions and greater cardiac burden.     

Arm position as a source of error in blood pressure measurement

The present study was designed to assess the value of correct positioning of a patient's arm when measuring blood pressure (BP). A total of 181 subjects were examined, 141 hypertensives on treatment, 25 untreated hypertensives, 15 normotensives. All the subjects underwent three BP measurements after a 5-min resting period in supine position. Then two BP readings were recorded in standing position with the arm either positioned by the patient's side or supported passively at patient's heart level. Average systolic BP (SBP) in standing position were 144.6 +/- 20.2 mmHg with the arm at the side and 136.4 +/- 21.1 mmHg with the arm at the heart level (p less than 0.001); average diastolic pressures were 99.0 +/- 12.0 mmHg and 90.2 +/- 12.3 mmHg (p less than 0.001), respectively. A fall in SBP greater than or equal to 20 mmHg from the supine to the upright position was detected in 18.2% of cases when measurement was performed at heart level; such a reduction was inapparent in two-thirds of cases when the arm was placed at the patient's body side. Incorrect positioning of a patient's arm during BP measurements in standing position leads to overestimation of BP values and masks the presence of postural hypotension.     

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.     

Insufficient duration of action of antihypertensive drugs mediates high blood pressure in the morning in hypertensive population: the Ohasama study

Blood pressure (BP) usually peaks in the morning. The circadian variation of the onset of cardiovascular disease mimics this circadian BP variation. To examine the determinants of the BP difference between the self-recorded BP in the morning (home BP) and daytime average ambulatory BP a cross sectional study was done in the general population of Ohasama, Japan. 1207 subjects > or = 20 years measured both home (more than 14 times) and ambulatory BPs (326 treated for hypertension and 881 untreated subjects), The prevalence of subjects with the systolic BP difference (home BP in the morning - daytime ambulatory BP) of > or = 10 mmHg (high morning BP) was 5.6% in untreated normotensives, 2.9% in untreated hypertensives, and 25.8% in treated hypertensives. This trend was also observed for diastolic pressure. Multiple regression analysis demonstrated that age, male sex, and use of antihypertensive drugs were positively associated and day-night difference of BP was negatively associated with the high morning BP, respectively. These results suggest an insufficient duration of antihypertensive action of widely used antihypertensive drugs in Japan from the 1980s to 1990s. The amplitude of the day-night difference of ambulatory BP in subjects with a high morning BP was lower (non-dipping) than that without high morning BP. The high morning BP is not necessarily accompanied by hypertension but might be mediated, at least in part, by an insufficient duration of action of antihypertensive drugs. The high morning BP accompanies so-called non-dipper pattern of circadian BP variation. An insufficient duration of action of drugs may partly mediate non-dipping in subjects with antihypertensive medication.     

Relationship between ambulatory blood pressure monitoring and response of blood pressure in male hypertensive adolescents to exercise

BACKGROUND: High blood pressure in the young has been related to the development of hypertension in adults; hence the importance of identifying adolescents with the risk of developing it.OBJECTIVE: To investigate the relationship between 24 h ambulatory blood pressure monitoring and the response of blood pressure in adolescents to exercise. DESIGN: A prospective and cross-sectional study. METHODS: We classified 101 men aged 13-18 years as obese hypertensive, lean hypertensive, obese normotensive, and lean normotensive. Mean blood pressure and variability were measured with ambulatory blood pressure monitoring, and expressed as 24 h, awake, and sleeping periods. Treadmill tests were also performed. RESULTS: Hypertensives and obese normotensives had higher ambulatory blood pressure monitoring values (P< 0.0001). Systolic blood pressure during sleep in obese subjects was significantly higher than that in lean usbjects (119.9 +/- 9 versus 113.6 +/- 8 mmHg, P < 0.001, obese hypertensives versus lean hypertensives; and 113.6 +/- 2 versus 103.0 +/- 2 mmHg, P < 0.002, obese normotensives versus lean normotensives) and nocturnal drop of systolic blood pressure was lower in obese subjects. We found a significant correlation between systolic blood pressure during ambulatory blood pressure monitoring and systolic blood pressure during moderate and maximal exercise for all periods (P < 0.0001). Blood pressure variability during awake period was higher in subjects with maximum exercise systolic blood pressure >/= 200 mmHg (7.4 +/- 2 versus 6.4 +/- 2%, P < 0.01).CONCLUSION: Systolic blood pressure measured by ambulatory blood pressure monitoring is related to response of systolic blood pressure to exercise and ambulatory blood pressure monitoring can identify groups of subjects at greater than normal risk through their higher blood pressure during sleep. Greater than normal blood pressure variability in adolescents is an indicator of the risk of reaching abnormal exercise values of systolic blood pressure. Higher casual blood pressure than ambulatory blood pressure monitoring values for adolescents should be considered abnormal.     

LOAD limits for ambulatory pulse pressure and double product in normotensive and hypertensive subjects.

OBJECTIVE: The aim of this study was to to determine possible daytime (awake hours) and nighttime (sleeping hours) LOAD limits for ambulatory pulse pressure (PP) and double product (DP) in hypertensive (HT) subjects and secondly to assess whether there were significant differences in the LOAD values between hypertensive (HT) and normotensive (NT) subjects. METHODS: Seventy-eight untreated essential HT (46 female, 32 male; mean age 51.9+/-1.4 years) and 115 NT (89 female, 26 male; mean age 40.8+/-1.1 years) subjects participated in this study. Ambulatory blood pressure monitoring (ABPM) devices were applied to these subjects for 48 hours. Different possible ambulatory PP LOAD limits between 40 and 55 mmHg with 5 mmHg increments and ambulatory DP LOAD limits between 6000 and 12,000 mmHg x beats/min with 1000 mmHg x beats/min increments were used. Then according to these limits, LOAD values of NT and HT subjects have been assessed for daytime, nighttime and 48 hours. RESULTS: There were significant differences between NT and HT subjects in all the values for both ambulatory PP and DP. Although mean (total, day and night mean) values of HT subjects were higher approximately by 20% than of NT subjects, LOAD values for ambulatory PP in HTs were 33%-415% higher than in NTs (p<0.001). Hypertensive subjects' mean (total, day and night mean) values of DP were by 23%-33% higher than NTs values, but LOAD values for ambulatory DP in hypertensives were approximately 43%-673% higher than in NT subjects (p<0.001). CONCLUSIONS: We showed that although there were significant differences in the 48-hour, daytime and nighttime PP and DP means between NT and HT subjects, these differences became more prominent when possible LOAD limits were used for ambulatory PP and DP, One of these possible ambulatory PP and DP LOAD limits can be used in the clinical settings if a relationship with the end-organ damage will be showed by further studies.     

Relationship between ambulatory blood pressure monitoring values and future occurrence of ischemic cerebrovascular and coronary events in hypertensive patients.

OBJECTIVES: To evaluate in a prospective study the relationship between 24-hour ambulatory blood pressure monitoring (ABPM) values and the occurrence of nonfatal ischemic cerebrovascular and coronary events in treated hypertensive patients. METHODS: Out of 8780 ABPM recordings we identified 79 hypertensive patients (both genders) who suffered a first nonfatal ischemic event, either cerebrovascular (stroke or transient ischemic attack) (STR/TIA, n = 48) or coronary (myocardial infarction, angina or coronary bypass/PTCA) (COR, n = 31) and 223 control-hypertensive patients (CTR) without any events during the same period who were fully matched (at the time of ABPM) for age, gender, antihypertensive therapy, presence of dyslipidemia or diabetes, and casual blood pressure (BP), in the proportion of 1 STR/TIA to 3 CTR and 1 COR to 6 CTR. Matched groups were compared for various ABPM parameters. RESULTS: On average, the time between ABPM and the occurrence of STR/TIA and COR events was respectively 32.4 (1 to 88) and 28.0 (1 to 73) months. For similar values of matched variables significant differences (p < 0.05) were observed between STR/TIA vs. CTR in 24-hour systolic BP (147.4 +/- 20.6 vs. 140.1 +/- 14.9 mmHg), daytime systolic BP (151.6 +/- 21.8 vs. 144.6 +/- 15.2 mmHg) and nighttime systolic BP (138.5 +/- 21.2 vs. 130.9 +/- 16.0 mmHg), and between COR vs. CTR in 24-hour systolic BP (143.5 +/- 19.5 vs. 135.2 +/- 15.6 mmHg), daytime systolic BP (146.3 +/- 20.5 vs. 139.6 +/- 15.9 mmHg) and nighttime systolic BP (138.1 +/- 19.7 vs. 126.2 +/- 16.4 mmHg), BP on rising (146.2 +/- 31.7 vs. 133.6 +/- 19.9 mmHg) and blunted nighttime BP dipping (5.3 +/- 7.4 vs. 9.60 +/- 6.0%). Versus CTR, STR/TIA showed a lower percentage of dippers (27.7 vs. 44.4%) and a higher percentage of extreme dippers (10.6 vs. 6.3%), nondippers (48.9 vs. 41.7%) and inverted dippers (12.8 vs. 7.6%). Versus CTR, the COR group showed (p < 0.02) a lower percentage of dippers (21.9 vs. 46.8%) and extreme dippers (3.1 vs. 4.3%) and a higher percentage of nondippers (56.3 vs. 43.0%) and inverted dippers (18.8 vs. 5.9%). CONCLUSIONS: This prospective study in treated hypertensive patients shows that both high ABPM values and abnormal daytime/nighttime BP profiles are associated with later occurrence of ischemic cerebrovascular and coronary events independently of casual BP values and other cardiovascular risk factors. This reinforces the idea that ABPM is a powerful predictor of future cardiovascular events.     

Rate of morning increase in blood pressure is elevated in hypertensives

BACKGROUND: We applied a new logistic curve fitting procedure to ambulatory blood pressure (ABP) recordings to determine whether the rate of increase in systolic (SBP), mean (MBP) and diastolic blood pressure (DBP) and heart rate (HR) in the morning is related to the level of BP in subjects. METHODS: The rate of transition in the morning and evening period was determined using a six-parameter double-logistic equation applied to 528 ABP recordings from a cardiovascular risk assessment clinic. Based on daytime BP (MBP, SBP, or DBP), the upper quartile (UQ, n = 132) and lower quartile (LQ) were compared. RESULTS: Subjects in the UQ of daytime MBP were hypertensive and showed greater day-night differences compared to normotensive subjects in the LQ (29 +/- 1 mm Hg for MBP compared to 20 +/- 1 mm Hg). The rate of morning increase in SBP and DBP was 42% and 30% greater in UQ subjects compared to the LQ subjects (P < .05). The rates of evening decrease in all BPs were 69% to 84% greater in the subjects in the UQ. Similar results were obtained if subjects were divided according to daytime SBP or DBP. The rate of morning increase in MBP was correlated with daytime BP, but not night-time or 24 h MBP. CONCLUSIONS: The rate of morning increase in BP is greater in those subjects with the highest daytime BP. The exaggerated rate of morning increase in BP in this group, which were all hypertensive, may also be important for greater cardiovascular risk.     

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.