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Biomedicine & Pharmacotherapy | 2005

Arterial stiffness independently predicts cardiovascular events in an elderly community : Longitudinal Investigation for the Longevity and Aging in Hokkaido County (LILAC) study

Osamu Matsuoka; K. Otsuka; Shougo Murakami; Norihiro Hotta; Gaku Yamanaka; Yutaka Kubo; Takashi Yamanaka; Makoto Shinagawa; S. Nunoda; Yoshiko Nishimura; K. Shibata; H. Saitoh; Masanori Nishinaga; Masayuki Ishine; Taizo Wada; Kiyohito Okumiya; Kozo Matsubayashi; S. Yano; K. Ichihara; G. Cornélissen; Franz Halberg; Toshio Ozawa

We investigated the predictive value of arterial stiffness to assess cardiovascular risk in elderly community-dwelling people by means of a multivariate Cox model. In 298 people older than 75 years (120 men and 178 women, average age: 79.6 years), brachial-ankle pulse wave velocity (baPWV) was measured between the right arm and ankle in a supine position. The LILAC study started on July 25, 2000, consultation was repeated yearly, and the last follow-up ended on November 30, 2004. During this follow-up span of 1227 days, there were nine cardiovascular deaths, the cause of death being myocardial infarction for two men and three women or stroke for two men and two women. In Cox proportional hazard models, baPWV as well as age, Mini-Mental State Examination (MMSE), Hasegawa Dementia Scale Revised (HDSR) and the low-frequency/high-frequency (LF/HF) ratio showed a statistically significant association with the occurrence of cardiovascular death. A two-point increase in MMSE and HDSR score significantly protected against cardiovascular death, the relative risk (RR) being 0.776 (P = 0.0369) and 0.753 (P = 0.0029), respectively. The LF/HF ratio also was significant (P = 0.025), but the other indices of HRV were not. After adjustment for age and HDSR, a 200 cm/s increase in baPWV was associated with a 30.2% increase in risk (RR = 1.302, 95% CI: 1.110-1.525), and a 500 cm/s increase in baPWV with a 93.3% increase in risk (RR = 1.933, 95% CI: 1.300-2.874, P = 0.0011), whereas the LF/HF ratio was no longer associated with a statistically significant increase in cardiovascular mortality. In elderly community-dwelling people, arterial stiffness measured by means of baPWV predicted the occurrence of cardiovascular death beyond the prediction provided by age, gender, blood pressure and cognitive functions. baPWV should be added to the cardiovascular assessment in various clinical settings, including field medical surveys and preventive screening. The early detection of risk by chronomics allows the timely institution of prophylactic measures, thereby shifting the focus from rehabilitation to prehabilitation medicine, as a public service to several Japanese towns.


Dementia and Geriatric Cognitive Disorders | 2009

Cardio-Ankle Vascular Index as a Predictor of Cognitive Impairment in Community-Dwelling Elderly People: Four-Year Follow-Up

Naomune Yamamoto; Gaku Yamanaka; Motonao Ishikawa; Emiko Takasugi; Shougo Murakami; Takashi Yamanaka; Masayuki Ishine; Kozo Matsubayashi; Toshiaki Hanafusa; Kuniaki Otsuka

Background/Aim: The relation between markers of generalized atherosclerosis and cognitive impairment in old age is controversial. The aim of the study was to evaluate the cardio-ankle vascular index (CAVI) as a predictor of longitudinal changes in cognitive function in older individuals. Methods: We evaluated the cognitive function in elderly people with high (AS(+)) and low (AS(–)) values of CAVI each year over 4 years. Results: The changes in the Hasegawa Dementia Scale Revised (HDS-R) and the mini-mental state examination (MMSE) at 4 years were significantly larger in the AS(+) group (AS(+) vs. AS(–) = –1.8 ± 4.4 vs. 0.3 ± 2.8 points and –1.1 ± 3.0 vs. 0.1 ± 2.3 points, p = 0.008 and 0.03, respectively). The annual changes in the HDS-R were significantly decreased from baseline at 1 year later to 4 years later in AS(+) (baseline vs. 1, 2, 3, 4 years = 26.5 vs. 25.0, 25.5, 25.7, 24.8 points, p < 0.001); in comparison, the annual changes in MMSE significantly decreased from the baseline over the 4 years in AS (+) (baseline vs. 1, 2, 3, 4 years = 26.8 vs. 26.2, 25.8, 26.4, 25.7 points, p = 0.002). Conclusion: The results of this study suggest that elderly people with a high CAVI value are at a greater risk of cognitive decline.


Clinical and Experimental Hypertension | 2005

Weekly Variation of Home and Ambulatory Blood Pressure and Relation Between Arterial Stiffness and Blood Pressure Measurements in Community-Dwelling Hypertensives

Shougo Murakami; Kuniaki Otsuka; Yutaka Kubo; Makoto Shinagawa; Osamu Matsuoka; Takashi Yamanaka; Shinichi Nunoda; Shin-ichiro Ohkawa; Yasushi Kitaura

Although blood pressure (BP) is a major determinant of pulse wave velocity (PWV), some treatments have independent effects on BP and arterial stiffness. Although both ambulatory BP (ABP) and self-measured BP at home (HBP) have become important measures for the diagnosis and management of hypertension, single day recordings may be insufficient for a proper diagnosis of hypertension or the evaluation of treatment efficacy. To evaluate weekly variations in BP using 7-day HBP and 7-day ABP monitoring and to determine the relation between arterial stiffness and BP measurements in community-dwelling patients with hypertension. We enrolled 68 community-dwelling hypertensive subjects in this study. Significant weekly variations in systolic blood pressure (SBP) and diastolic blood pressure (DBP) were found in the awake ABP data (p < .01, respectively), while no significant weekly variations in the asleep ABP or the morning and evening HBP data were observed. In untreated subjects, significant correlations were obtained between the brachial-ankle PWV and the average awake SBP, the average asleep SBP and the average SBP measured by HBP in the evening. In treated subjects, only the average SBP measured by HBP in the morning was significantly correlated with the baPWV. Differences in the weekly variations in BP were observed between HBP and ABP monitoring. In addition, the morning systolic HBP was not correlated with arterial stiffness in untreated subjectswith hypertension but was correlated in treated subjects. Relations between the morning HBP and arterial stiffness might be attributed to morning surges in BP and/or trough levels of antihypertensive drugs.


Biomedicine & Pharmacotherapy | 2005

Chronoecological health watch of arterial stiffness and neuro-cardio-pulmonary function in elderly community at high altitude (3524 m), compared with Japanese town

K. Otsuka; Tsering Norboo; Y. Otsuka; H. Higuchi; M. Hayajiri; C. Narushima; Y. Sato; T. Tsugoshi; Shougo Murakami; Taizo Wada; Masayuki Ishine; Kiyohito Okumiya; Kozo Matsubayashi; S. Yano; T. Chogyal; D. Angchuk; K. Ichihara; G. Cornélissen; Franz Halberg

Effects of high altitude on arterial stiffness and neuro-cardio-pulmonary function were studied. Blood pressure (BP) and heart rate (HR) were measured in a sitting position on resting Ladakhis, living at an altitude of 3250-4647 m (Phey village, 3250 m: 17 men and 55 women; Chumathang village, 4193 m: 29 men and 47 women; Sumdo village, 4540 m: 38 men and 57 women; and Korzok village, 4647 m: 84 men and 70 women). The neuro-cardio-pulmonary function, including the Kohs block design test, the Up and Go, the Functional Reach and the Button tests, was examined in 40 elderly subjects (19 men and 21 women, mean age: 74.7 +/- 3.3 years) in Leh, Ladakh (altitude: 3524 m), for comparison with 324 elderly citizens (97 men and 227 women, mean age: 80.7 +/- 4.7 years) of Tosa, Japan (altitude: 250 m). Cardio-Ankle Vascular Index (CAVI) was measured as the heart-ankle pulse wave velocity (PWV) in these subjects using a VaSera CAVI instrument (Fukuda Denshi, Tokyo). SpO(2) decreased while Hb and diastolic BP increased with increasing altitude. At higher altitude, residents were younger and leaner. Women in Leh vs. Tosa had a poorer cognitive function, estimated by the Kohs block design test (3.7 +/- 3.6 vs. 16.4 +/- 9.6 points, P < 0.0001) and poorer ADL functions (Functional Reach: 13.7 +/- 7.0 cm vs. 25.3 +/- 8.7 cm, P < 0.0001; Button test: 22.5 +/- 4.8 vs. 14.8 +/- 5.7 s, P < 0.0001). Time estimation was shorter at high altitude (60-s estimation with counting: 41.1% shorter in men and 23.0% shorter in women). A higher voltage of the QRS complex was observed in the ECG of Leh residents, but two times measurement of CAVI showed no statistically significant differences between Leh and Tosa (two times of CAVI measures; 9.49 vs. 10.01 m/s and 9.41 vs. 10.05 m/s, respectively), suggesting that most residents succeed to adapt sufficiently to the high-altitude environment. However, correlation of CAVI with age shows several cases who show an extreme increase in CAVI. Thus, for the prevention of stroke and other adverse cardiovascular outcomes, including dementia, CAVI may be very useful, especially at high altitude. In conclusion, elderly people living at high altitude have a higher risk of cardiovascular disease than low-latitude peers. To determine how these indices are associated with maintained cognitive function deserves further study by the longitudinal follow-up of these communities in terms of longevity and aging in relation to their neuro-cardio-pulmonary function.


Hypertension Research | 2011

Impact of outdoor temperature on prewaking morning surge and nocturnal decline in blood pressure in a Japanese population

Shougo Murakami; Kuniaki Otsuka; Tatsuji Kono; Akiko Soyama; Tatsuya Umeda; Naomune Yamamoto; Hideaki Morita; Gaku Yamanaka; Yasushi Kitaura

Seasonal variations in blood pressure (BP) have often been attributed to meteorological factors, especially changes in outdoor temperature. We evaluated the direct association between meteorological factors and circadian BP variability. Twenty-four-hour ambulatory BP was monitored continuously for 7 days in 158 subjects. Mean awake, asleep, morning (first 2 h after waking) BP, prewaking morning BP surge (morning systolic BP (SBP)−mean SBP during the 2-h period before waking) and nocturnal BP decline were measured each day. We compared BP values for the lowest and highest days with regard to the daily mean outdoor temperature and mean atmospheric pressure. Morning BP and prewaking morning BP surge on the coldest day were significantly higher than those on the warmest day (morning SBP, 136.6±1.6 vs. 133.1±1.5 mm Hg, P=0.002; morning diastolic BP, 84.4±0.9 vs. 82.6±0.9 mm Hg, P=0.02; and prewaking morning BP surge, 20.8±1.3 vs. 15.3±1.3 mm Hg, P=0.0004). The magnitude of nocturnal BP decline on the coldest day was significantly greater than that on the warmest day (15.8±0.7 vs. 13.9±0.7%, P=0.01). Outdoor temperature is an important determinant of morning BP, prewaking morning BP surge and the magnitude of nocturnal BP decline. These findings may have important implications in management of hypertension and prevention of cardiovascular events.


Diabetes Research and Clinical Practice | 2009

Lifestyle intervention reversed cognitive function in aged people with diabetes mellitus: Two-year follow up

Naomune Yamamoto; Gaku Yamanaka; Emiko Takasugi; Motonao Ishikawa; Takashi Yamanaka; Shougo Murakami; Toshiaki Hanafusa; Kozo Matsubayashi; Kuniaki Otsuka

To clarify the reversibility of cognitive decline in elderly people with type 2 diabetes, we evaluated cognitive function in 55 elderly people with diabetes and 74 control subjects before and after lifestyle intervention. Lifestyle intervention has a beneficial effect on cognitive decline in elderly people with type 2 diabetes mellitus.


Biomedicine & Pharmacotherapy | 2005

Effect of aging on blood pressure in Leh, Ladakh, a high-altitude (3524 m) community, by comparison with a Japanese town.

K. Otsuka; Tsering Norboo; Y. Otsuka; H. Higuchi; M. Hayajiri; C. Narushima; Y. Sato; T. Tsugoshi; Shougo Murakami; Taizo Wada; Masayuki Ishine; Kiyohito Okumiya; Kozo Matsubayashi; S. Yano; T. Choygal; D. Angchuk; K. Ichihara; G. Cornélissen; Franz Halberg

The effect of aging on blood pressure (BP) and heart rate (HR) was investigated in a cross-sectional study in the high-altitude community of Leh, Ladakh (altitude: 3524 m) and a Japanese community in U town, Hokkaido (altitude: 25 m). BP and HR were obtained in a sitting position from 332 subjects 13-81 years of age in Ladakh, and from 216 Japanese citizens, 24-79 years of age. Measurements were taken after a 2-min rest, using a semi-automated BP device (UA-767 PC, A and D Co. LTD, Tokyo). High-altitude people showed higher diastolic BP and HR values than lowland people (83.2 vs. 76.9 mmHg and 78.6 vs. 69.2 bpm, P < 0.001), but no difference in systolic BP. Highland people also showed a steeper BP increase with age than the lowland people (systolic BP: 0.7476 vs. 0.3179 mmHg/year, P < 0.0005; diastolic BP: 0.3196 vs. 0.0750 mmHg/year, P < 0.001). This chronoecologic investigation in Ladakh examined the circulation as a physiological system at high-altitude. Our data indicate the need for a more comprehensive cardiovascular assessment for a better diagnosis and a more fruitful treatment. Longitudinal observations of effects of socio-ecologic factors on the cardiovascular system should help prevent strokes and other cardiovascular events, especially at high altitude.


Biomedicine & Pharmacotherapy | 2005

Fractal analysis of heart rate variability and mortality in elderly community-dwelling people -- Longitudinal Investigation for the Longevity and Aging in Hokkaido County (LILAC) study.

Norihiro Hotta; K. Otsuka; Shougo Murakami; Gaku Yamanaka; Yutaka Kubo; Osamu Matsuoka; Takashi Yamanaka; Makoto Shinagawa; S. Nunoda; Yoshiko Nishimura; K. Shibata; H. Saitoh; Masanori Nishinaga; Masayuki Ishine; Taizo Wada; Kiyohito Okumiya; Kozo Matsubayashi; S. Yano; K. Ichihara; G. Cornélissen; Franz Halberg

AIM Fractal analysis of heart rate (HR) variability (HRV) has been used as a new approach to evaluate the risk of mortality in various patient groups. Aim of this study is to examine the prognostic power of detrended fluctuation analysis (DFA) and traditional time- and frequency-domain analyses of HR dynamics as predictors of mortality among elderly people in a community. METHODS We examined 298 people older than 75 years (average age: 79.6 years) and 1-h ambulatory ECG was monitored. During the last 10 min, deep respiration (6-s expiration and 4-s inspiration) was repeated six times in a supine position. Time-domain and frequency-domain measures were determined by the maximum entropy method. Scaling exponents of short-term (<11 beats, alpha 1) and longer-term (>11 beats, alpha 2) were determined by the DFA method. Six estimates, obtained from 10-min segments, were averaged to derive mean values for the entire recording span. These average values were denoted Alpha 1 and Alpha 2, estimates obtained during the first 10-min segment Alpha 1 S and Alpha 2 S, and those during the last 10-min segment Alpha 1E and Alpha 2E, respectively. The LILAC study started on July 25, 2000 and ended on November 30, 2004. We used Cox regression analysis to calculate relative risk (RR) and 95% confidence interval (CI) for all-cause mortality. Significance was considered at a value of P < 0.05. RESULTS Gender, age and Alpha 2E showed a statistically significant association with all-cause mortality. In univariate analyses, gender was significantly associated with all-cause mortality, being associated with a RR of 3.59 (P = 0.00136). Age also significantly predicted all-cause mortality and a 5-year increase in age was associated with a RR of 1.49 (P = 0.01809). The RR of developing all-cause mortality predicted by a 0.2-unit increase in Alpha 2E was 0.58 (P = 0.00390). Other indices of fractal analysis of HRV did not have predictive value. In multivariate analyses, when both Alpha 2E and gender were used as continuous variables in the same model, Alpha 2E remained significantly associated with the occurrence of all-cause mortality (P = 0.02999). After adjustment for both gender and age, a 0.2-unit increase in Alpha 2E was associated with a RR of 0.61 (95% CI: 0.42-0.90, p = 0.01151). CONCLUSION An intermediate-term fractal-like scaling exponent of RR intervals was a better predictor of death than the traditional measures of HR variability in elderly community-dwelling people. It is noteworthy that the longer-term (alpha 2) rather than the short-term fractal component (alpha 1) showed predictive value for all-cause mortality, which suggests that an increase in the randomness of intermediate-term HR behavior may be a specific marker of neurohumoral and sympathetic activation and therefore may also be associated with an increased risk of mortality.


Journal of the American Geriatrics Society | 2010

Insomnia Increases Insulin Resistance and Insulin Secretion in Elderly People

Naomune Yamamoto; Gaku Yamanaka; Kaya Ishizawa; Motonao Ishikawa; Shougo Murakami; Takashi Yamanaka; Kiyohito Okumiya; Masayuki Ishine; Kozo Matsubayashi; Kuniaki Otsuka

and D. Her CST score became normal (20/20). With hindsight, several hypotheses might explain the dramatic effects of valproate. First, valproate has high protein binding, more than 80%, mainly to albumin. Only free drug can cross the plasma membrane and bind with the receptor for pharmacological action. Free valproate concentrations mirror cerebral spinal fluid concentration. Valproate has a narrow therapeutic index, and toxicity may be encountered slightly above the upper end of the therapeutic range. For instance, a lowering of serum albumin from 40 to 30 g/L may double the amount of free valproate. In this patient, serum albumin was 24 g/L. Second, in renal failure, unknown compounds displace valproate from protein-binding sites and may increase the free fraction up to 20% to 30% (normally 10%). This patient had a toxic free fraction and concentration in the serum of 24% and 11 mg/L (normal range 5–10 mg/L) and liquor of 22% and 10 mg/L (normal range 5–10 mg/L). Third, mycophenolate is also a strongly protein-bound drug (92–98%) and may have further increased the free valproate level. Finally, this patient had an intermediatemetabolizer (CYP2C9 3) heterozygous genotype, which can also lead to a higher free valproate level. It was concluded that valproate intoxication caused by a too-high (toxic) free concentration could entirely explain the RPD. The subtherapeutic total serum valproate level was initially misleading. Neurotoxicity has been described only in patients with normal or high total levels of valproate. Conditions such as hypoalbuminemia and renal failure can lead to a significant increase in free concentrations, resulting in (neuro)toxicity even if the total valproate level is within or below therapeutic range. In patients with renal failure, hypoalbuminemia, or prescription of highly protein bound medication, monitoring of free valproate concentration is recommended. Free drug concentration of valproate is easily measured in clinical laboratories, and this method is widely available.


Biomedicine & Pharmacotherapy | 2005

Depressive mood is independently related to stroke and cardiovascular events in a community.

Gaku Yamanaka; K. Otsuka; Norihiro Hotta; Shougo Murakami; Yutaka Kubo; Osamu Matsuoka; Emiko Takasugi; Takashi Yamanaka; Makoto Shinagawa; S. Nunoda; Yoshiko Nishimura; K. Shibata; H. Saitoh; Masanori Nishinaga; Masayuki Ishine; Taizo Wada; Kiyohito Okumiya; Kozo Matsubayashi; S. Yano; S. Ishizuka; K. Ichihara; G. Cornélissen; Franz Halberg

By means of a multivariate Cox model, we investigated the predictive value of a depressive mood on vascular disease risk in middle-aged community-dwelling people. In 224 people (88 men and 136 women; mean age: 56.8 +/- 11.2 years) of U town, Hokkaido (latitude: 43.45 degrees N, longitude: 141.85 degrees E), a chronoecological health watch was started in April 2001. Consultations were repeated every 3 months. Results at the November 30, 2004 follow-up are presented herein. 7-day/24-h blood pressure (BP) and heart rate (HR) monitoring started on a Thursday, with readings taken at 30-min intervals between 07:00 h and 22:00 h and at 60-min intervals between 22:00 h and 07:00 h. Data stored in the memory of the monitor (TM-2430-15, A and D company, Japan) were retrieved and analyzed on a personal computer with a commercial software for this device. Subjects were asked to answer a self-administered questionnaire inquiring about 15 items of a depression scale, at the start of study and again after 1-2 years. Subjects with a score higher by at least two points at the second versus first screening were classified as having a depressive mood. The other subjects served as the control group. The mean follow-up time was 1064 days, during which four subjects suffered an adverse vascular outcome (myocardial infarction: one man and one woman; stroke: two men). Among the variables used in the Cox proportional hazard models, a depressive mood, assessed by the Geriatric Depression Scale (GDS), as well as the MESOR of diastolic (D) BP (DBP-MESOR) and the circadian amplitude of systolic (S) BP (SBP-Amplitude) showed a statistically significant association with the occurrence of adverse vascular outcomes. The GDS score during the second but not during the first session was statistically significantly associated with the adverse vascular outcome. In univariate analyses, the relative risk (RR) of developing outcomes was predicted by a three-point increase in the GDS scale (RR = 3.088, 95% CI: 1.375-6.935, P = 0.0063). Increases of 5 mmHg in DBP-MESOR and of 3 mmHg in SBP-Amplitude were associated with RRs of 2.143 (95% CI: 1.232-3.727, P = 0.0070) and 0.700 (95% CI: 0.495-0.989, P = 0.0430), respectively. In multivariate analyses, when both the second GDS score and the DBP-MESOR were used as continuous variables in the same model, GDS remained statistically significantly associated with the occurrence of cardiovascular death. After adjustment for DBP-MESOR, a three-point increase in GDS score was associated with a RR of 2.172 (95% CI: 1.123-4.200). Monday endpoints of the 7-day profile showed a statistically significant association with adverse vascular outcomes. A 5 mmHg increase in DBP on Monday was associated with a RR of 1.576 (95% CI: 1.011-2.457, P = 0.0446). The main result of the present study is that in middle-aged community-dwelling people, a depressive mood predicted the occurrence of vascular diseases beyond the prediction provided by age, gender, ABP, lifestyle and environmental conditions, as assessed by means of a multivariate Cox model. A depressive mood, especially enhanced for 1-2 years, was associated with adverse vascular outcomes. Results herein suggest the clinical importance of repetitive assessments of a depressive mood and the need to take sufficient care of depressed subjects. Another result herein is that circadian and circaseptan characteristics of BP variability measured 7-day/24-h predicted the occurrence of vascular disease beyond the prediction provided by age, gender, depressive mood and lifestyle, as assessed by means of a multivariate Cox model. Earlier, we showed that the morning surge in BP on Mondays was statistically significantly higher compared with other weekdays. Although a direct association between the Monday surge in BP and cardiovascular events could not be demonstrated herein, it is possible that the BP surge on Monday mornings may also trigger cardiovascular events. We have shown that depressive people exhibit a more prominent circaseptan variation in SBP, DBP and the double product (DP) compared to non-depressed subjects. In view of the strong relation between depression and adverse cardiac events, studies should be done to ascertain that depression is properly diagnosed and treated. Chronodiagnosis and chronotherapy can reduce an elevated blood pressure and improve the altered variability in BP and HR, thus reducing the incidence of adverse cardiac events. This recommendation stands at the basis of chronomics, focusing on prehabilitation in preference to rehabilitation, as a public service offered in several Japanese towns.

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K. Otsuka

University of Minnesota

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