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Kei Asayama

Publications and source records attributed to Kei Asayama.

33 records · Page 2Linked to original sources

White-coat hypertension as a risk factor for the development of home hypertension: the Ohasama study.

BACKGROUND: White-coat hypertension is a condition characterized by elevated blood pressure (BP) in medical settings combined with normal ambulatory-recorded BP or self-measured BP at home (home BP). However, it is unknown whether this condition represents a transient state in the development of hypertension outside medical settings. METHODS: We followed up 128 subjects with white-coat hypertension (home BP <135/85 mm Hg and office BP > or = 140/90 mm Hg) for 8 years and compared the risk of progression with home hypertension (home BP > or = 135/85 mm Hg or start of treatment with antihypertensive medication) with 649 sustained normotensive subjects (home BP <135/85 mm Hg and office BP <140/90 mm Hg) using data from population-based home BP measurement projects in Japan. RESULTS: During the 8-year follow-up period, 60 subjects (46.9%) with white-coat hypertension and 144 (22.2%) with sustained normotension progressed to home hypertension. The odds ratio of subjects with white-coat hypertension for progression to home hypertension (adjusted for possible confounding factors) was significantly higher than for subjects with sustained normotension (odds ratio, 2.86; P<.001). This association was observed independent of baseline home BP levels. CONCLUSION: The results from the present 8-year follow-up study demonstrate that white-coat hypertension is a transitional condition to hypertension outside medical settings, suggesting that white-coat hypertension may carry a poor cardiovascular prognosis.

Adult↗

Use of 2003 European Society of Hypertension-European Society of Cardiology guidelines for predicting stroke using self-measured blood pressure at home: the Ohasama study.

AIMS: To evaluate the predictive power of the risk stratification system proposed in the 2003 European Society of Hypertension-European Society of Cardiology (2003 ESH-ESC) guidelines and to compare self-measured blood pressure at home (HBP) with casual-screening blood pressure (CBP) for prediction of first stroke among a general Japanese population. METHODS AND RESULTS: HBP and CBP were measured in 1702 subjects (> or = 40 years) who had no history of stroke and who were followed for an average of 11 years. The subjects were assigned to one of five groups with differential risk stratification according to the 2003 ESH-ESC criteria: average risk, low added risk, moderate added risk, high added risk, and very high added risk. Even in the low risk group a significantly high risk for stroke was observed, and there was a linear step up of stroke risk based on HBP, as well as on CBP. On the basis of HBP classification, a higher stroke incidence was observed in the high and very high groups compared with CBP classification. CONCLUSION: The risk stratification system proposed in the 2003 ESH-ESC guidelines is valid for the prediction of stroke in this Japanese study population, and has a stronger predictive power when based on HBP than on CBP. The results indicate the usefulness of HBP for the prediction of stroke risk in individuals.

Blood Pressure↗

Efficacy and duration of action of the four selective angiotensin II subtype 1 receptor blockers, losartan, candesartan, valsartan and telmisartan, in patients with essential hypertension determined by home blood pressure measurements.

Our objective was to compare the efficacy and duration of action of 4 angiotensin II receptor blockers (ARBs)--losartan (25-100 mg), candesartan (2-12 mg), valsartan (40-80 mg), and telmisartan (10-40 mg)-in patients with essential hypertension using self-measurement of blood pressure at home (home BP) and to examine the differential effect of the four ARBs on home pulse pressure (home PP). After a 2-week run-in period, each of the 4 ARBs was assigned to subjects who were diagnosed as having hypertension on the basis of home BP and who were over 30 years old. The subjects were asked to take the ARB once daily in the morning and to measure home BP once in the evening and in the morning. We compared the efficacy of each ARB on home BP and home PP and assessed the duration of the BP-lowering effect using the morning effect versus evening effect ratio (M/E ratio). The antihypertensive effects of telmisartan on home systolic BP (SBP) both in the evening and in the morning and on home diastolic BP (DBP) in the morning were significantly greater than those of losartan. The effect of each ARB on home BP in the morning and in the evening was expressed as a ratio (M/E ratio). The M/E ratios of SBP/DBP in patients treated with losartan, candesartan, valsartan, and telmisartan were 0.49/0.16, 0.69/1.01, 0.82/0.88, and 0.88/0.88, respectively. The home PP-lowering effect was greater for valsartan and telmisartan than for losartan and candesartan in the morning. Among the 4 ARBs, the duration of the BP-lowering effect of losartan did not persist throughout 24 hr. The effects of the other 3 ARBs, in particular telmisartan, persisted over 24 hr when they were administered once daily in the morning. In addition, the duration of the PP-lowering effect was similar to that of the BP-lowering effect. Such long-acting property of several ARBs is essential for the modern antihypertensive treatment, and home BP measurements are useful for determining the duration of action of antihypertensive drugs. Losartan, 25 mg a day, which is usually used as an initial dose in Japan, is apparently insufficient to obtain adequate antihypertensive effect and sufficient duration of action.

Angiotensin II Type 1 Receptor Blockers↗

Isolated uncontrolled hypertension at home and in the office among treated hypertensive patients from the J-HOME study.

OBJECTIVES: To evaluate the current status of blood pressure (BP) control as measured at home and in the office, as well as to clarify and compare the prevalence and characteristics of isolated uncontrolled hypertension as measured at home (home hypertension) and in the office (office hypertension). DESIGN: A cross-sectional study. SETTING: Primary care offices in Japan. PARTICIPANTS: A sample of 3400 patients with essential hypertension (mean age, 66 years; males, 45%) receiving antihypertensive treatment. RESULTS: Overall, the mean home systolic BP (SBP)/diastolic BP (DBP) was 140/82 mmHg, and the mean office SBP/DBP was 143/81 mmHg. Of the 3400 subjects, 19% had controlled hypertension (home SBP/DBP < 135/85 mmHg and office SBP/DBP < 140/90 mmHg), 23% had isolated uncontrolled home hypertension (home SBP/DBP >/= 135/85 mmHg and office SBP/DBP < 140/90 mmHg), 15% had isolated uncontrolled office hypertension (home SBP/DBP < 135/85 mmHg and office SBP/DBP < 140/90 mmHg), and 43% had uncontrolled hypertension (home SBP/DBP >/= 135/85 mmHg and office SBP/DBP >/= 140/90 mmHg). Compared to controlled hypertension, factors associated with isolated uncontrolled home hypertension included obesity, relatively higher office SBP, habitual drinking, and the use of two or more prescribed antihypertensive drugs. Compared to uncontrolled hypertension, factors associated with isolated uncontrolled office hypertension included female gender, lower body mass index, and relatively lower office SBP. CONCLUSIONS: The use of all four, three of four, or all three predictive factors might be useful for the clinician to suspect isolated uncontrolled home or office hypertension.

Aged↗

Efficacy of combination antihypertensive therapy with low-dose indapamide: assessment by blood pressure self-monitoring at home.

We examined the effects of the addition of low-dose indapamide to antihypertensive drugs of other classes, as well as its duration of action, using blood pressure (BP) self-monitoring at home. Seventy-six patients undergoing monotherapy with a calcium channel blocker (CCB), angiotensin converting-enzyme inhibitor (ACEI), or angiotensin AT1-receptor blocker (ARB), but had an average morning home systolic BP (SBP) > or =135 mmHg or diastolic BP (DBP) > or =85 mmHg, were studied. Indapamide (1 mg) was added to their existing treatment once daily for 4 weeks. The additional hypotensive effects of indapamide were evaluated by casual and home BPs, and the results were compared among the three groups of subjects classified according to their initial drug treatment classes. The morning/evening (M/E) ratio of BP reduction was calculated to assess the duration of the effect. Overall, indapamide significantly (P < 0.001) lowered morning home BP (147 +/- 12/87 +/- 9 mmHg to 135 +/- 12/81 +/- 9 mmHg), evening home BP (138 +/- 15/79 +/- 10 mmHg to 126 +/- 12/73 +/- 9 mmHg), and casual BP (145 +/- 21/86 +/- 14 mmHg to 136 +/- 17/81 +/- 13 mmHg). All groups showed significant indapamide-induced home SBP/DBP decreases, whereas only the ACEI and ARB groups, but not the CCB group, showed a home pulse pressure (PP) reduction. Evening SBP and PP decreases were significantly greater in the ARB group than in the CCB group. The mean M/E ratio with indapamide was 0.95 for SBP and 0.85 for DBP. Low-dose indapamide used in combination can provide additional anti-hypertensive efficacy lasting for 24 h. The added effect of indapamide may be more prominent on ARBs than on CCBs.

Aged↗

Ambulatory blood pressure and 10-year risk of cardiovascular and noncardiovascular mortality: the Ohasama study.

The objective of this study was to elucidate the long-term prognostic significance of ambulatory blood pressure. Ambulatory and casual blood pressure values were obtained from 1332 subjects (872 women and 460 men) aged >or=40 years from the general population of a rural Japanese community. Survival was then followed for 14 370 patient years and analyzed by a Cox hazard model adjusted for possible confounding factors. There were 72 cardiovascular deaths during the 10.8-year follow-up. The relationship between 24-hour systolic blood pressure and the cardiovascular mortality risk was U-shaped in the first 5 years, then changed to J-shaped over the rest of the 10.8-year follow-up. After censoring the first 2 years of data, the risk flattened until it again increased for the fifth quintile of 24-hour systolic blood pressure for the 10.8-year follow-up period. For 24-hour diastolic blood pressure, the J-shaped relationship remained unchanged, regardless of follow-up duration and censoring. Ambulatory systolic blood pressure values consistently showed stronger predictive power for cardiovascular mortality risk than did casual systolic blood pressure in the 10.8-year follow-up data, whereas such relationships became more marked after censoring the first 2 years. When nighttime and daytime systolic blood pressure values were simultaneously included in the same Cox model, only nighttime blood pressure significantly predicted the cardiovascular mortality risk for the 10.8-year follow-up data. We conclude that the relationship between ambulatory systolic blood pressure and cardiovascular mortality is not U-shaped or J-shaped, and that nighttime blood pressure has better prognostic value than daytime blood pressure.

Aged↗

Prediction of stroke by self-measurement of blood pressure at home versus casual screening blood pressure measurement in relation to the Joint National Committee 7 classification: the Ohasama study.

BACKGROUND AND PURPOSE: To compare the predictive power of self-measured home blood pressure (HBP) and casual blood pressure (CBP) for stroke risk in relation to the Joint National Committee 7 (JNC-7) classification. METHODS: HBP and CBP measurements were taken in 1702 subjects (> or =40 years) without a history of stroke, who were followed up for an average of 11 years. Subjects were classified into 4 groups on the basis of either HBP or CBP, according to the JNC-7 criteria: group 1 (HBP <115/75 mm Hg; CBP <120/80 mm Hg); group 2 (115/75< or =HBP<135/85 mm Hg; 120/80< or =CBP<140/90 mm Hg); group 3 (135/85< or =HBP<150/95 mm Hg; 140/90< or =CBP<160/100 mm Hg); and group 4 (HBP> or =150/95 mm Hg; CBP > or =160/100 mm Hg). Groups 2, 3, and 4 were further divided into 2 subgroups (a and b): those without and with cardiovascular disease risks, respectively. The risk of the first stroke in these groups was examined by the Cox hazards model adjusted for age and sex. RESULTS: The stroke risk in groups 3b and 4b (defined by HBP and CBP) was 2 to 5x higher than that in group 1 with significant differences. The risk in groups 2a, 3a, and even 4a was not significantly different from that in group 1 by the CBP-based classification, but the risk in group 4a was significantly higher than that in group 1 by the HBP-based classification, which also showed a stepwise increase in risk from groups 2a to 4a. CONCLUSIONS: The JNC-7 classification had a stronger predictive power using HBP-based classification compared with CBP-based classification, suggesting the usefulness of HBP in the management of hypertension.

Aged↗

Prognostic value of home heart rate for cardiovascular mortality in the general population: the Ohasama study.

BACKGROUND: Recently, the advantages of self-measurement of blood pressure (BP) at home have been recognized. The same advantages could also be applicable to resting heart rate (HR) values assessed at home using a device designed for home BP measurement. However, there have been no studies investigating whether home HR values predict the risk of cardiovascular disease mortality. We therefore investigated the usefulness of HR values in predicting cardiovascular mortality using a device that allowed self-measurement of BP and HR at home. METHODS: The association between the home-measured resting HR and the 10-year risk of cardiovascular mortality was examined in 1780 Japanese individuals >/=40 years of age who had no significant arrhythmias. A Cox proportional hazards model that adjusted for major risk factors was used. RESULTS: An increase of 5 beats/min in the morning home HR measurement was associated with a 17% increase in the risk of cardiovascular mortality (95% confidence interval 5% to 30%). This relationship was also statistically significant after adjustment for home BP values. Even when home-measured systolic BP was within the normal range (<135 mm Hg), subjects with HR >/=70 beats/min had a higher risk of cardiovascular mortality (relative hazard 2.16, 95% confidence interval 1.21 to 3.85) than those with normal systolic BP and HR values. CONCLUSIONS: Self-measurement of HR at home, together with self-measurement of BP, is a simple method of providing useful clinical information for assessing cardiovascular risk.

Adult↗

Progress report on the HOMED-BP Study: hypertension objective treatment based on measurement by electrical devices of blood pressure study.

Hypertension Objective treatment based on Measurement by Electrical Devices of Blood Pressure Study (HOMED BP Study) is the first large-scale intervention trial in Japan using a Prospective Randomized Open Blinded Endpoint (PROBE) design to determine an optimal target blood pressure (BP) level on the basis of self-measured BP at home, and an optimal initial course of antihypertensive medication. The registered patients are randomized to either a more intensive BP-lowering group (home systolic BP < 125 mmHg and diastolic < 80 mmHg) or a less intensive group (home systolic/diastolic BP within the range 134-125/84-80 mmHg) by host computer via the Internet. The differential effect of three classes of initial antihypertensive regimens on the prognosis, i.e., calcium antagonist (Ca-A), angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin II receptor antagonist (ARB), which are used most frequently in Japan, are examined. Three regimens are also randomly assigned to the host computer via the Internet. A pilot study was started in May 2001. In March 2002, the number of participating doctors was 461. At the end of March 2002, 546 patients were recruited. Of these, 412 (202 men and 210 women, aged 58.4 +/- 10.2 y) were randomized. Patients will be recruited until February, 2006 and followed for 7 years.

Adult↗

How many times should blood pressure be measured at home for better prediction of stroke risk? Ten-year follow-up results from the Ohasama study.

OBJECTIVE: To determine the optimum number of blood pressure self-measurements taken at home (home blood pressure) in relation to their predictive value for stroke risk. METHODS: We obtained more than 14 measurements of home blood pressure from 1491 people aged >or=40 years without a history of stroke in the general population in Japan, and followed them up after a mean period of 10.6 years. The prognostic significance of blood pressure for stroke risk was examined using the Cox proportional hazards regression model, which was adjusted for possible confounding factors. RESULTS: The predictive value of home blood pressure increased progressively with the number of measurements, showing the highest predictive value with the average of whole measurements (mean = 25 measurements, 35% increase in the risk of stroke per 10 mmHg elevation in blood pressure). The initial home blood pressure values (one measurement) showed a significantly greater relation with stroke risk than conventional blood pressure values (mean of two measurements) (19/8% increase in the risk of stroke per 10 mmHg elevation in initial home/conventional systolic blood pressure values, respectively). CONCLUSIONS: There was no threshold for the number of home blood pressure measurements within the range of 1-14 measurements for increasing the predictive power of stroke risk, suggesting that as many measurements as possible, preferably more than 14 measurements, is recommended for better prediction of stroke risk. It should be emphasized that home blood pressure has a stronger predictive power than does conventional blood pressure, even for a lower number of measurements.

Adult↗

The second progress report on the Hypertension Objective treatment based on Measurement by Electrical Devices of Blood Pressure (HOMED-BP) study.

BACKGROUND: The Hypertension Objective treatment based on Measurement by Electrical Devices of Blood Pressure (HOMED-BP) study is a large-scale intervention trial to determine both optimal target blood pressure (BP) on the basis of self-measured BP at home, and optimal initial antihypertensive medication. OBJECTIVE: To investigate the quality of randomization at the end of March 2003, and BP-controlled conditions during initial 6 months. METHODS: We evaluated the number of patients randomized by the end of March 2003, and BP changes during the initial 6 months based on intention-to-treat analysis. RESULTS: By the end of March 2003, a total of 1086 patients (12% of a planned randomization of 9000 patients) had been randomized. Among 653 patients who had been followed for > or =6 months after randomization, mean systolic/diastolic BPs at randomization in the calcium antagonist, angiotensin-converting enzyme and angiotensin II receptor blocker groups were 149/89, 150/89 and 149/88 mmHg, respectively. Blood pressures were reduced after 3 months (137/83, 139/82 and 136/82 mmHg, respectively), and further reduced after 6 months (134/81, 135/80 and 133/80 mmHg, respectively), with no significant differences identified between groups. In more- and less-intensive BP-lowering groups, mean systolic/diastolic BPs at randomization were 149/88 and 150/89 mmHg, respectively. Although BPs were reduced after treatment for 3 months (137/83 and 137/82 mmHg, respectively) and 6 months (134/80 and 135/80 mmHg, respectively) in each target group, significant differences were still not observed between groups. CONCLUSIONS: Good quality of randomization was observed at the end of March 2003, but rate of achievement for target BPs was insufficient.

Angiotensin II Type 1 Receptor Blockers↗

Prediction of ischaemic and haemorrhagic stroke by self-measured blood pressure at home: the Ohasama study.

OBJECTIVE: To examine the predictive value of self-measured blood pressure values taken at home (home blood pressure) for risk of stroke and subtypes. METHODS: We obtained home blood pressure measurements from 1702 people, aged > or =40 years, without a history of stroke, in the general population in Japan, and continued follow-up after a mean period of 10.6 years. The prognostic significance of blood pressure for stroke risk was examined using the Cox proportional hazards regression model, which was adjusted for possible confounding factors. RESULTS: There was a linear relationship between home blood pressure and risk of stroke and subtypes. On average, each 10/5 mmHg elevation in home systolic/diastolic blood pressure respectively, was associated with an approximately 30/20% respectively, higher risk of total stroke. A similar relationship was observed for the risk of haemorrhagic stroke (intracerebral and subarachnoid haemorrhage), and the risk of ischaemic stroke [cerebral infarction and transient ischaemic attack (TIA)]. The risk of stroke and subtypes showed a significantly greater relation with home blood pressure values compared to conventional blood pressure values. CONCLUSIONS: This is the first study to demonstrate that home blood pressure is an independent predictor for haemorrhagic and ischaemic stroke, in the general population.

Adult↗

Control of blood pressure as measured at home and office, and comparison with physicians' assessment of control among treated hypertensive patients in Japan: First Report of the Japan Home versus Office Blood Pressure Measurement Evaluation (J-HOME) study.

The Japan Home versus Office Blood Pressure Measurement Evaluation (J-HOME) study was conducted to measure the control of blood pressure (BP) as evaluated by home BP measurement among 3,400 patients with essential hypertension (mean age: 66 years; females: 55%) receiving antihypertensive treatment in primary care settings in Japan. The purpose of this first report was to compare characteristics of BP control as measured at home and in the clinic (office) and define their association with BP control as evaluated by physicians. Mean systolic/diastolic BP (SBP/DBP) values were 140/82 mmHg for home BP and 143/81 mmHg for office BP. BP levels were not adequately controlled among approximately 60% of the patients, according to reference values described in the national guidelines (office BP: <140/90 mmHg; home BP: <135/85 mmHg). Even among patients evaluated by physicians as having excellent or fairly good BP control, office and home SBP values were insufficiently controlled in approximately 50%. Although the tendency was more remarkable among older patients, whose recommended target BP levels are higher than those of middle-aged patients in the Japanese Hypertension Society 2000 criteria, office and home BP values were not adequately controlled in approximately 50% of the middle-aged patients whose BP control was evaluated as good. Our findings suggest that an important reason why home and office BP values are not adequately controlled is that physicians approve relatively higher BP levels under treatment, even among middle-aged patients.

Aged↗

T+31C polymorphism of angiotensinogen gene and nocturnal blood pressure decline: the Ohasama study.

BACKGROUND: We assessed the association between several polymorphisms of angiotensinogen gene (AGT) and essential hypertension using ambulatory blood pressure (BP). METHODS: We recruited 802 subjects in a rural Japanese community who were aged >40 years and who gave written informed consent for monitoring of their ambulatory BP and genetic analysis (the Ohasama Study). As a polymorphism of AGT, T+31C, which is in complete linkage disequilibrium with M235T, was determined using the TaqMan polymerase chain reaction method. RESULTS: The genotype distribution of AGT/T-+31C in the Ohasama Study was similar to that in another large Japanese population. Although there was no significant difference in 24-h and daytime ambulatory BP values, the nighttime BP was significantly lower in the subjects with TT, resulting in greater decline of nocturnal systolic (P = .090) and diastolic (P = .025) BP in subjects with TT. CONCLUSIONS: AGT/T+31C is associated with the circadian BP variation but not with BP level in the Japanese general population.

Angiotensinogen↗