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Subclinical arterial damage in masked hypertensive patients detected by home blood pressure
258A
Special Symposium: Hypertension in the Japanese Population
CONCLUSION: In older hypertensive patients, exaggerated morning BP surge is partly associated with the morning increase in platelet aggregation and is a risk factor for hypertensive cerebrovascular disease in relation to a morning increase in sympathetic activity. Key Words: Thrombosis, Ambulatory blood pressure monitoring, Morning hypertension
P-683 PROGNOSTIC SIGNIFICANCE OF DAY-BY-DAY VARIABILITY OF SELF-MEASURED BLOOD PRESSURE AT HOME: THE OHASAMA STUDY Masahiro Kikuya, Takayoshi Ohkubo, Kei Asayama, Hirohito Metoki, Taku Obara, Junichiro Hashimoto, Kazuhito Totsune, Hiroshi Satoh, Yutaka Imai. Dept. Planning for Drug Develop. and Clin. evaluation, Tohoku Univ.; Tohoku Univ. 21st Century COE Program “Comprehensive Research and Education Center for Planning of Drug Development and Clinical Evaluation”; Clin. Pharm.and Therapeutics; Envir. Health Sci, Tohoku Univ., Sendai, Japan. It is well known that a short-term blood pressure (BP) variability associates with the risk of cardiovascular diseases. We, then, investigated prognostic significance of day-by-day BP variability, as assessed by self-measured BP at home (HBP). We measured HBP on 2578 subjects aged 35 years or more without a history of stroke in a general population of Ohasama, Japan. Stroke morbidity was followed for a mean duration of 10 years. The HBP was measured once every morning and evening for 4 weeks. Morning measurements were made within 1 h of awakening, before breakfast, before taking drugs, in sitting position with at least 2 min. rest. Evening HBP was measured just before going to bed. The day-by-day variability of HBP in each individual was defined as standard deviation (SD) of all HBP measurements. A Cox proportional hazards model that adjusted for major risk factors was used. There were 168 first strokes during the follow-up period (cerebral infarction 116, cerebral hemorrhage 31, SAH 8, TIA 7, unclear 2). An increase of 5 mmHg in the SD of both morning and evening systolic HBP was associated with a 25 % (95% confidence interval [CI] 0 to 56%, p ⫽ 0.048) increase in the risk of stroke. For diastolic BP, similar trend was observed in the SD of morning and evening diastolic HBP, (relative hazard [RH] 1.24, 95% CI 0.95 – 1.62, p⫽0.12 for morning; RH 1.24, 95%CI 0.92 – 1.67, p⫽0.16 for evening). For the risk of stroke subtypes, day-by-day variability was significantly associated with the risk of cerebral infarction [RHs 1.42 (95%CI 1.10 to 1.82, p⫽0.006), 1.31 (95%CI 1.01 to 1.69, p⫽0.042), 1.31 (95%CI 0.96 to 1.80, p⫽0.087) and 1.24 (95%CI 0.87 to 1.78, p⫽0.23) for every 5 mmHg increase in SD of morning systolic, evening systolic, morning diastolic and evening diastolic BP, respectively], while there were no consistent association between SD of HBP values and cerebral hemorrhage. In conclusion, dayby-day BP variability derived from HBP is an independent predictor for ischemic stroke risk in general population.
AJH–May 2005–VOL. 18, NO. 5, PART 2
sion. However, the clinical implications of the rate of BP changes have never been investigated. We evaluated the possible association between the 24-hour time rate of systolic blood pressure (SBP) variation derived from computerized analysis of ambulatory BP monitoring (ABPM) data and the extent of common carotid artery intima-media thickness (CCAIMT) in normotensive (n⫽237) and in uncomplicated hypertensive subjects (n⫽284). No antihypertensive and lipid-lowering treatment had ever been administered in any of the 521 subjects who underwent ABPM on a usual working day. The time rate of SBP variation was computed as the first derivative of the SBP values against time. The 24-hour rate of SBP variation was significantly (p⬍0.001) higher in hypertensive (0.609mmHg/min, 95%CI:0.596-0.622) than in normotensive individuals (0.566mmHg/min, 95%CI:0.554-0.576) even after adjusting for baseline characteristics, day-night BP changes, 24-hour heart rate (HR), SBP- and HR variability. In the hypertensive subgroup, the multiple linear regression models revealed independent determinants of CCA-IMT in the following rank order: age (p⬍0.001), 24-hour time rate of SBP variation (p⬍0.001), smoking (p⫽0.002), male gender (p⫽0.008) and triglycerides (p⫽0.017). Age (p⬍0.001) and 24-hour time rate of SBP variation (p⫽0.015) were the only significant determinants of CCA-IMT in normotensive individuals. A 0.1mmHg/min increase in the 24-hour rate of SBP variation correlated to an increment of 0.024mm (95%CI:0.0050.042) and 0.026mm (95%CI:0.013-0.040) in the CCA-IMT of the normotensive and hypertensive subjects respectively even after adjustment for all baseline characteristics and other ABPM parameters. Thus, the rate of BP fluctuations is greater in hypertensive patients and correlates to CCA intima-media thickening. These findings indicate that steeper BP variations may produce a greater stress on the vessel wall and consequently result in medial hypertrophy of the large arteries. Key Words: time rate, common carotid artery intima-media thickness, blood pressure monitoring
P-685 SUBCLINICAL ARTERIAL DAMAGE IN MASKED HYPERTENSIVE PATIENTS DETECTED BY HOME BLOOD PRESSURE Yoshio Matsui, Kazuomi Kario, Joji Ishikawa, Kazuo Eguchi, Satoshi Hoshide, Kazuyuki Shimada. Internal Medicine, Miwa Municipal Hospital, Miwa, Yamaguchi, Japan; Cardiovascular Medicine, Jichi Medical School, Minamikawachi, Tochigi, Japan. Recent studies have demonstrated that the phenomenon of “Masked Hypertension” have a poor cardiovascular prognosis. We examined whether masked hypertensive patients have the impaired arterial properties.
Key Words: self-measurement, population study, blood pressure measurement
P-684 ASSOCIATION OF THE TIME RATE OF BLOOD PRESSURE VARIATION WITH INCREASED COMMON CAROTID ARTERY INTIMA-MEDIA THICKNESS Efstathios Manios, Georgios Tsivgoulis, Konstantinos Spengos, Gerassimos Barlas, Christos Papamichael, Konstantinos Vemmos, Joanna Spiliopoulou, Konstantinos Dolianitis, Nikolaos Zakopoulos. Department of Clinical Therapeutics, University of Athens, Athens, Greece; Department of Neurology, University of Athens, Athens, Greece. The extent of target-organ damage has been positively associated with the magnitude of blood pressure (BP) variability in essential hyperten-
We consecutively enrolled 156 outpatients (mean age: 69.5 years) without antihypertensive medication, and classified them into 4 subgroups (Normotension; NT, White Coat Hypertension; WCHT, Masked Hypertension; MHT, Sustained Hypertension; SHT) by using home (135/85 mmHg) and office (140/90 mmHg) blood pressure (BP) values.
AJH–May 2005–VOL. 18, NO. 5, PART 2
These 4 subgroups were compared with arterial wall stiffness assessed by brachial-ankle pulse wave velocity (baPWV) and atherosclerosis assessed by carotid intima-media thickness (CIMT). Patients with MHT (72.5 years) and SHT (71.0 years) were older than other groups, but comparable with other parameters. BaPWV was higher in the MHT (1978.1 cm/sec) and in the SHT (2167.1 cm/sec) than in the other groups. CIMT was higher in the MHT (0.88 mm) than in the NT (0.72 mm) and the WCHT (0.77 mm). In conclusion, this study suggests that the functional and structural changes in the arteries progress in masked hypertensive patients detected by home BP. Key Words: atherosclerosis, pulse wave velocity, home blood pressure
P-686 PROGNOSTIC SIGNIFICANCE OF NOCTURNAL DIPPING FOR STROKE AND HEART DISEASE MORTALITY RISK: THE OHASAMA STUDY Hirohito Metoki, Takayoshi Ohkubo, Masahiro Kikuya, Kei Asayama, Taku Obara, Junichiro Hashimoto, Kazuhito Totsune, Haruhisa Hoshi, Hiroshi Satoh, Yutaka Imai. Clinical Pharmacology and Therapeutics, Tohoku University Graduate School of Pharmaceutical Science and Medicine; Drug Development and Clinical Evaluation; Environmental Health Sciences, Tohoku University Graduate School of Pharmaceutical Science and Medicine; Comprehensive Research and Education Center for Planning of Drug Development and Clinical Evaluation, Tohoku University 21st Century COE Program, Sendai, Japan; Ohasama Hospital, Ohasama, Japan. Objective: To examine the relationship between pattern of circadian blood pressure(BP) variation and the risk of mortality from stroke and heart disease(HD). Methods: Mortality in 1507 subjects aged 40 years and over in Ohasama, Japan, was followed for average 10.6 years. The association between mortality risk from cardiovascular disease and the pattern of circadian BP was analyzed by Cox proportional hazards model adjusted for possible confounding factors. Definition of types of circadian BP variation is as follows: dipper (10-19% nocturnal decline from diurnal level), non-dipper (0-9%), inverted dipper (⬍0%, nocturnal elevation) and extreme dipper (ⱖ20%). Results: HD mortality risk was significantly high in inverted dippers and in non-dippers compared with dippers, [relative hazard (RH) 3.73, 95% confidence intervals (95%CI) 1.54 to 9.02 and RH 2.28 (95%CI 1.05 to 4.93), respectively]. HD mortality risk significantly increased with decrease in nocturnal decline [RH 1.9 per 1-SD (12.7%) decrease in nocturnal decline in systolic BP (SBP) (95%CI 1.23 to 2.84)].There was a significant inverse association between cerebral infarction (CI) mortality risk and nocturnal dipping [RH 2.81 per 1-SD (12.7%) decrease of nocturnal decline in SBP (95%CI 1.08 to 7.34)]. Significantly higher mortality risk from intracerebral hemorrhage (ICH) was observed in extreme dippers compared with that in dippers [RH 9.9 (95%CI 2.17 to 44.79)]. The mortality risk from ICH increased with increase in nocturnal decline in SBP [RH 5.8 per 1-SD (12.7%) increase of nocturnal decline in SBP (95%CI 2.19 to 15.28)]. Conclusion: Circadian BP variation affects types of cardiovascular mortality risk. A large nocturnal decline in BP or a large diurnal peak in BP mediates ICH mortality, while, disturbed circadian BP variation or high nighttime BP was associated with HD and CI mortalities. Key Words: japanease, population study, blood pressure mesurements
Special Symposium: Hypertension in the Japanese Population
259A
P-687 IMPACT OF SLEEP SYSTOLIC BLOOD PRESSURE ON BRAIN ATROPHY IN ELDERLY HYPERTENSION- JICHI MEDICAL SCHOOL ABPM STUDY, WAVE 2 CORE Michiaki Nagai, Kazuomi Kario, Kazuyuki Shimada. Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical School, Tochigi, Japan; Department of General Medicine, Hiroshima Prefectural Hospital, Hiroshima, Japan. Background: Recent studies demonstrated a relationship between brain atrophy and hypertension in the elderly. However, the insular cortex (IC) has been suggested to be a key site in limbic-autonomic integration, modulating our cardiovascular system. Especially, in human, the left IC is associated with parasympathetic cardiovascular tone, while the right IC with sympathetic cardiovascular tone. We examined ambulatory blood pressure (BP) and brain atrophy including IC. Methods: We performed ambulatory BP monitoring and brain MRI in 29 elderly hypertensives. The volume of total brain matter (TBM) and IC were measured using an Intensity Contour-Mapping Algorithm. Results: Mean values of 24-hr, awake, and sleep systolic/diastolic BP (SBP/ DBP) were 141.2⫾14.1/76.8⫾10.2mmHg, 145.0⫾14.2/78.9⫾10.8mmHg and 134.7⫾20.3/72.0⫾12.0mmHg. Mean values of TBM, left IC and right IC were 969.1⫾122.2cm3, 6.17⫾1.07cm3 and 7.22⫾0.90cm3. On stepwise regression analysis including clinical characteristics and ambulatory BP measures during 24-hr, awake, and sleep periods, sleep SBP (B:–5.10, 95%CI:–7.80 to –2.40, p⫽0.00068) and sleep DBP (B:5.68, 95%CI:1.17 to 10.24, p⫽0.017) were significant and independent predictors of TBM volume. Sleep SBP (B:–0.0218, 95%CI:–0.42 to –0.002, p⫽0.035) was a significant and independent predictor of left IC volume. There were no predictors of right IC volume. Conclusion: In elderly hypertensives, sleep systolic BP was a significant independent predictor of brain atrophy including that of the left IC. These findings may provide some insight into a possible role of sleep systolic BP in the pathogenesis of cognitive dysfunction and autonomic disturbance in elderly hypertensives. Particularly, left IC atrophy may shift the predominant sympathovagal balance during sleep toward a more increased sympathetic tone. From this perspective, strict BP control including sleep period may be important for preventing cognitive and autonomic dysfunction. Key Words: sleep blood pressure, insular cortex, brain
P-688 THE FEASIBILITY OF 24-H AMBULATORY BLOOD PRESSURE MONITORING AND THE PREVALENCE OF WHITE-COAT EFFECT IN VERY ELDERLY AGED >80 YEARS Kenichi Sakakura, Kazuomi Kario, Masataka Okuno, Joji Ishikawa, Kazuyuki Shimada. Internal medicine, Public Kiwa clinic, Kiwa, Mie, Japan; Department of Cardiology, Jichi medical school, Minamikawachi, Tochigi, Japan; Public Kamishima clinic, Toba, Mie, Japan. Background: In a developed country, the prevalence of very elderly aged ⱖ80 years is rapidly increasing. However, there is few data on feasibility of 24-h ambulatory blood pressure monitoring (ABPM) and white-coat effect (WCE). The purpose of this study was to evaluate 1) the feasibility of 24-h ABPM and 2) the WCE (defined as the difference between clinic blood pressure[CBP] and awake ambulatory blood pressure[ABP]) in very elderly aged ⱖ80 years. Method: We consecutively recruited 51 Japanese patients(10 men and 41 women) agedⱖ80 years, who receive regular treatment for stable chronic diseases such as hypertension, hyperlipidemia, diabetes, chronic gastritis, and osteoporosis. 27 patients live alone without any family member. 24-h ABPM was performed after detailed explanation according to a predefined checklist. CBP were taken before and after 24-h ABPM. ABP readings were obtained automatically with a 30 min interval. The number of BP data successfully obtained was documented for each patient. First 24-h BP measurements (Maximum 48 measurements) were used for analysis.
Special Symposium: Hypertension in the Japanese Population
CONCLUSION: In older hypertensive patients, exaggerated morning BP surge is partly associated with the morning increase in platelet aggregation and is a risk factor for hypertensive cerebrovascular disease in relation to a morning increase in sympathetic activity. Key Words: Thrombosis, Ambulatory blood pressure monitoring, Morning hypertension
P-683 PROGNOSTIC SIGNIFICANCE OF DAY-BY-DAY VARIABILITY OF SELF-MEASURED BLOOD PRESSURE AT HOME: THE OHASAMA STUDY Masahiro Kikuya, Takayoshi Ohkubo, Kei Asayama, Hirohito Metoki, Taku Obara, Junichiro Hashimoto, Kazuhito Totsune, Hiroshi Satoh, Yutaka Imai. Dept. Planning for Drug Develop. and Clin. evaluation, Tohoku Univ.; Tohoku Univ. 21st Century COE Program “Comprehensive Research and Education Center for Planning of Drug Development and Clinical Evaluation”; Clin. Pharm.and Therapeutics; Envir. Health Sci, Tohoku Univ., Sendai, Japan. It is well known that a short-term blood pressure (BP) variability associates with the risk of cardiovascular diseases. We, then, investigated prognostic significance of day-by-day BP variability, as assessed by self-measured BP at home (HBP). We measured HBP on 2578 subjects aged 35 years or more without a history of stroke in a general population of Ohasama, Japan. Stroke morbidity was followed for a mean duration of 10 years. The HBP was measured once every morning and evening for 4 weeks. Morning measurements were made within 1 h of awakening, before breakfast, before taking drugs, in sitting position with at least 2 min. rest. Evening HBP was measured just before going to bed. The day-by-day variability of HBP in each individual was defined as standard deviation (SD) of all HBP measurements. A Cox proportional hazards model that adjusted for major risk factors was used. There were 168 first strokes during the follow-up period (cerebral infarction 116, cerebral hemorrhage 31, SAH 8, TIA 7, unclear 2). An increase of 5 mmHg in the SD of both morning and evening systolic HBP was associated with a 25 % (95% confidence interval [CI] 0 to 56%, p ⫽ 0.048) increase in the risk of stroke. For diastolic BP, similar trend was observed in the SD of morning and evening diastolic HBP, (relative hazard [RH] 1.24, 95% CI 0.95 – 1.62, p⫽0.12 for morning; RH 1.24, 95%CI 0.92 – 1.67, p⫽0.16 for evening). For the risk of stroke subtypes, day-by-day variability was significantly associated with the risk of cerebral infarction [RHs 1.42 (95%CI 1.10 to 1.82, p⫽0.006), 1.31 (95%CI 1.01 to 1.69, p⫽0.042), 1.31 (95%CI 0.96 to 1.80, p⫽0.087) and 1.24 (95%CI 0.87 to 1.78, p⫽0.23) for every 5 mmHg increase in SD of morning systolic, evening systolic, morning diastolic and evening diastolic BP, respectively], while there were no consistent association between SD of HBP values and cerebral hemorrhage. In conclusion, dayby-day BP variability derived from HBP is an independent predictor for ischemic stroke risk in general population.
AJH–May 2005–VOL. 18, NO. 5, PART 2
sion. However, the clinical implications of the rate of BP changes have never been investigated. We evaluated the possible association between the 24-hour time rate of systolic blood pressure (SBP) variation derived from computerized analysis of ambulatory BP monitoring (ABPM) data and the extent of common carotid artery intima-media thickness (CCAIMT) in normotensive (n⫽237) and in uncomplicated hypertensive subjects (n⫽284). No antihypertensive and lipid-lowering treatment had ever been administered in any of the 521 subjects who underwent ABPM on a usual working day. The time rate of SBP variation was computed as the first derivative of the SBP values against time. The 24-hour rate of SBP variation was significantly (p⬍0.001) higher in hypertensive (0.609mmHg/min, 95%CI:0.596-0.622) than in normotensive individuals (0.566mmHg/min, 95%CI:0.554-0.576) even after adjusting for baseline characteristics, day-night BP changes, 24-hour heart rate (HR), SBP- and HR variability. In the hypertensive subgroup, the multiple linear regression models revealed independent determinants of CCA-IMT in the following rank order: age (p⬍0.001), 24-hour time rate of SBP variation (p⬍0.001), smoking (p⫽0.002), male gender (p⫽0.008) and triglycerides (p⫽0.017). Age (p⬍0.001) and 24-hour time rate of SBP variation (p⫽0.015) were the only significant determinants of CCA-IMT in normotensive individuals. A 0.1mmHg/min increase in the 24-hour rate of SBP variation correlated to an increment of 0.024mm (95%CI:0.0050.042) and 0.026mm (95%CI:0.013-0.040) in the CCA-IMT of the normotensive and hypertensive subjects respectively even after adjustment for all baseline characteristics and other ABPM parameters. Thus, the rate of BP fluctuations is greater in hypertensive patients and correlates to CCA intima-media thickening. These findings indicate that steeper BP variations may produce a greater stress on the vessel wall and consequently result in medial hypertrophy of the large arteries. Key Words: time rate, common carotid artery intima-media thickness, blood pressure monitoring
P-685 SUBCLINICAL ARTERIAL DAMAGE IN MASKED HYPERTENSIVE PATIENTS DETECTED BY HOME BLOOD PRESSURE Yoshio Matsui, Kazuomi Kario, Joji Ishikawa, Kazuo Eguchi, Satoshi Hoshide, Kazuyuki Shimada. Internal Medicine, Miwa Municipal Hospital, Miwa, Yamaguchi, Japan; Cardiovascular Medicine, Jichi Medical School, Minamikawachi, Tochigi, Japan. Recent studies have demonstrated that the phenomenon of “Masked Hypertension” have a poor cardiovascular prognosis. We examined whether masked hypertensive patients have the impaired arterial properties.
Key Words: self-measurement, population study, blood pressure measurement
P-684 ASSOCIATION OF THE TIME RATE OF BLOOD PRESSURE VARIATION WITH INCREASED COMMON CAROTID ARTERY INTIMA-MEDIA THICKNESS Efstathios Manios, Georgios Tsivgoulis, Konstantinos Spengos, Gerassimos Barlas, Christos Papamichael, Konstantinos Vemmos, Joanna Spiliopoulou, Konstantinos Dolianitis, Nikolaos Zakopoulos. Department of Clinical Therapeutics, University of Athens, Athens, Greece; Department of Neurology, University of Athens, Athens, Greece. The extent of target-organ damage has been positively associated with the magnitude of blood pressure (BP) variability in essential hyperten-
We consecutively enrolled 156 outpatients (mean age: 69.5 years) without antihypertensive medication, and classified them into 4 subgroups (Normotension; NT, White Coat Hypertension; WCHT, Masked Hypertension; MHT, Sustained Hypertension; SHT) by using home (135/85 mmHg) and office (140/90 mmHg) blood pressure (BP) values.
AJH–May 2005–VOL. 18, NO. 5, PART 2
These 4 subgroups were compared with arterial wall stiffness assessed by brachial-ankle pulse wave velocity (baPWV) and atherosclerosis assessed by carotid intima-media thickness (CIMT). Patients with MHT (72.5 years) and SHT (71.0 years) were older than other groups, but comparable with other parameters. BaPWV was higher in the MHT (1978.1 cm/sec) and in the SHT (2167.1 cm/sec) than in the other groups. CIMT was higher in the MHT (0.88 mm) than in the NT (0.72 mm) and the WCHT (0.77 mm). In conclusion, this study suggests that the functional and structural changes in the arteries progress in masked hypertensive patients detected by home BP. Key Words: atherosclerosis, pulse wave velocity, home blood pressure
P-686 PROGNOSTIC SIGNIFICANCE OF NOCTURNAL DIPPING FOR STROKE AND HEART DISEASE MORTALITY RISK: THE OHASAMA STUDY Hirohito Metoki, Takayoshi Ohkubo, Masahiro Kikuya, Kei Asayama, Taku Obara, Junichiro Hashimoto, Kazuhito Totsune, Haruhisa Hoshi, Hiroshi Satoh, Yutaka Imai. Clinical Pharmacology and Therapeutics, Tohoku University Graduate School of Pharmaceutical Science and Medicine; Drug Development and Clinical Evaluation; Environmental Health Sciences, Tohoku University Graduate School of Pharmaceutical Science and Medicine; Comprehensive Research and Education Center for Planning of Drug Development and Clinical Evaluation, Tohoku University 21st Century COE Program, Sendai, Japan; Ohasama Hospital, Ohasama, Japan. Objective: To examine the relationship between pattern of circadian blood pressure(BP) variation and the risk of mortality from stroke and heart disease(HD). Methods: Mortality in 1507 subjects aged 40 years and over in Ohasama, Japan, was followed for average 10.6 years. The association between mortality risk from cardiovascular disease and the pattern of circadian BP was analyzed by Cox proportional hazards model adjusted for possible confounding factors. Definition of types of circadian BP variation is as follows: dipper (10-19% nocturnal decline from diurnal level), non-dipper (0-9%), inverted dipper (⬍0%, nocturnal elevation) and extreme dipper (ⱖ20%). Results: HD mortality risk was significantly high in inverted dippers and in non-dippers compared with dippers, [relative hazard (RH) 3.73, 95% confidence intervals (95%CI) 1.54 to 9.02 and RH 2.28 (95%CI 1.05 to 4.93), respectively]. HD mortality risk significantly increased with decrease in nocturnal decline [RH 1.9 per 1-SD (12.7%) decrease in nocturnal decline in systolic BP (SBP) (95%CI 1.23 to 2.84)].There was a significant inverse association between cerebral infarction (CI) mortality risk and nocturnal dipping [RH 2.81 per 1-SD (12.7%) decrease of nocturnal decline in SBP (95%CI 1.08 to 7.34)]. Significantly higher mortality risk from intracerebral hemorrhage (ICH) was observed in extreme dippers compared with that in dippers [RH 9.9 (95%CI 2.17 to 44.79)]. The mortality risk from ICH increased with increase in nocturnal decline in SBP [RH 5.8 per 1-SD (12.7%) increase of nocturnal decline in SBP (95%CI 2.19 to 15.28)]. Conclusion: Circadian BP variation affects types of cardiovascular mortality risk. A large nocturnal decline in BP or a large diurnal peak in BP mediates ICH mortality, while, disturbed circadian BP variation or high nighttime BP was associated with HD and CI mortalities. Key Words: japanease, population study, blood pressure mesurements
Special Symposium: Hypertension in the Japanese Population
259A
P-687 IMPACT OF SLEEP SYSTOLIC BLOOD PRESSURE ON BRAIN ATROPHY IN ELDERLY HYPERTENSION- JICHI MEDICAL SCHOOL ABPM STUDY, WAVE 2 CORE Michiaki Nagai, Kazuomi Kario, Kazuyuki Shimada. Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical School, Tochigi, Japan; Department of General Medicine, Hiroshima Prefectural Hospital, Hiroshima, Japan. Background: Recent studies demonstrated a relationship between brain atrophy and hypertension in the elderly. However, the insular cortex (IC) has been suggested to be a key site in limbic-autonomic integration, modulating our cardiovascular system. Especially, in human, the left IC is associated with parasympathetic cardiovascular tone, while the right IC with sympathetic cardiovascular tone. We examined ambulatory blood pressure (BP) and brain atrophy including IC. Methods: We performed ambulatory BP monitoring and brain MRI in 29 elderly hypertensives. The volume of total brain matter (TBM) and IC were measured using an Intensity Contour-Mapping Algorithm. Results: Mean values of 24-hr, awake, and sleep systolic/diastolic BP (SBP/ DBP) were 141.2⫾14.1/76.8⫾10.2mmHg, 145.0⫾14.2/78.9⫾10.8mmHg and 134.7⫾20.3/72.0⫾12.0mmHg. Mean values of TBM, left IC and right IC were 969.1⫾122.2cm3, 6.17⫾1.07cm3 and 7.22⫾0.90cm3. On stepwise regression analysis including clinical characteristics and ambulatory BP measures during 24-hr, awake, and sleep periods, sleep SBP (B:–5.10, 95%CI:–7.80 to –2.40, p⫽0.00068) and sleep DBP (B:5.68, 95%CI:1.17 to 10.24, p⫽0.017) were significant and independent predictors of TBM volume. Sleep SBP (B:–0.0218, 95%CI:–0.42 to –0.002, p⫽0.035) was a significant and independent predictor of left IC volume. There were no predictors of right IC volume. Conclusion: In elderly hypertensives, sleep systolic BP was a significant independent predictor of brain atrophy including that of the left IC. These findings may provide some insight into a possible role of sleep systolic BP in the pathogenesis of cognitive dysfunction and autonomic disturbance in elderly hypertensives. Particularly, left IC atrophy may shift the predominant sympathovagal balance during sleep toward a more increased sympathetic tone. From this perspective, strict BP control including sleep period may be important for preventing cognitive and autonomic dysfunction. Key Words: sleep blood pressure, insular cortex, brain
P-688 THE FEASIBILITY OF 24-H AMBULATORY BLOOD PRESSURE MONITORING AND THE PREVALENCE OF WHITE-COAT EFFECT IN VERY ELDERLY AGED >80 YEARS Kenichi Sakakura, Kazuomi Kario, Masataka Okuno, Joji Ishikawa, Kazuyuki Shimada. Internal medicine, Public Kiwa clinic, Kiwa, Mie, Japan; Department of Cardiology, Jichi medical school, Minamikawachi, Tochigi, Japan; Public Kamishima clinic, Toba, Mie, Japan. Background: In a developed country, the prevalence of very elderly aged ⱖ80 years is rapidly increasing. However, there is few data on feasibility of 24-h ambulatory blood pressure monitoring (ABPM) and white-coat effect (WCE). The purpose of this study was to evaluate 1) the feasibility of 24-h ABPM and 2) the WCE (defined as the difference between clinic blood pressure[CBP] and awake ambulatory blood pressure[ABP]) in very elderly aged ⱖ80 years. Method: We consecutively recruited 51 Japanese patients(10 men and 41 women) agedⱖ80 years, who receive regular treatment for stable chronic diseases such as hypertension, hyperlipidemia, diabetes, chronic gastritis, and osteoporosis. 27 patients live alone without any family member. 24-h ABPM was performed after detailed explanation according to a predefined checklist. CBP were taken before and after 24-h ABPM. ABP readings were obtained automatically with a 30 min interval. The number of BP data successfully obtained was documented for each patient. First 24-h BP measurements (Maximum 48 measurements) were used for analysis.