-
Kosaku NITTA, Takashi AKIBA, Koichi SUZUKI, Keiko UCHIDA, Tetsuya OGAW ...
2004 Volume 27 Issue 8 Pages
527-533
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
Cardiovascular disease in association with coronary artery calcification (CAC) is the leading cause of death in patients with end-stage renal disease (ESRD). The evaluation of CAC has been performed by electron beam CT scan. The purpose of the present study was to assess CAC using multi-detector spiral CT (MDCT) and to evaluate contributors to CAC in these patients. Fifty-three patients on chronic hemodialysis participated in this study. Their mean age was 61.0±9.6 years, and the mean duration of dialysis therapy was 6.7±5.4 years. We used an automatic device to measure arterial pulse wave velocity (PWV) as an index of arterial wall stiffness. The aortic calcification index (ACI) was quantified morphometrically by CT scan. The CAC score correlated positively with ACI score (r =0.863, p <0.0001). Linear regression analysis indicated that the CAC scores correlated positively with age (r =0.406, p =0.0023), C-reactive protein (r =0.38, p =0.0047) and PWV (r =0.303, p =0.0271). Stepwise regression analysis indicated that ACI (β-coefficient=0.862, p <0.0001) and arterial PWV (β-coefficient=0.303, p <0.0001) were independently associated with CAC score. The mean CAC score of patients with cardiac events (2,568.5±2,575.1 mm3) was significantly higher than that (258.0±409.2 mm3) of patients without cardiac events. In conclusion, our results showed clearly that assessment of CAC score using MDCT may be predictive for detecting the presence of coronary artery disease. CAC is indirectly associated with increased arterial stiffness and the extent of aortic calcification in hemodialysis patients. We did not find a significant correlation between CAC score and parameters of mineral metabolism, including serum levels of calcium, phosphorus and parathyroid hormone. A longitudinal prospective study is required to assess the predictive value of this technique in determining cardiac events in large numbers of hemodialysis patients. (Hypertens Res 2004; 27: 527-533)
View full abstract
-
Hiroyasu UEDA, Tomoshige HAYASHI, Kei TSUMURA, Kiyomichi YOSHIMARU, Ya ...
2004 Volume 27 Issue 8 Pages
535-540
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
It has been reported that the reflection waveform in the ascending aortic pressure is associated with systemic arterial stiffness. Stiffening of the aortic walls leads to a decrease in coronary perfusion and an increase in restenosis rate. The purpose of this study was to evaluate whether the reflection waveform in the ascending aortic pressure could be used to predict restenosis after percutaneous coronary stenting. One hundred and three patients who underwent percutaneous coronary stenting were enrolled in this study. We measured the inflection time and augmentation index (AIx) to determine the reflection waveform in the ascending aortic pressure at angioplasty. We then prospectively investigated the effect of inflection time and AIx in relation to the subsequent risk of restenosis after coronary stenting. After adjustments for age, gender, smoking habits, hypertension, type 2 diabetes, hypercholesterolemia, stent size, and heart rate, the odds ratio of restenosis in inflection time was 4.62 (95% confidence interval (CI), 1.39 to 15.4) for the lowest tertile of the inflection time level compared with the highest tertile level. As for AIx, the odds ratio of restenosis was 6.96 (95% CI, 1.93 to 25.1) for the highest tertile of the AIx level compared with the lowest tertile level. Inflection time and AIx are related to restenosis after percutaneous coronary stenting. (Hypertens Res 2004; 27: 535-540)
View full abstract
-
Yuhua SUN, Weidong PEI, Yongjian WU, Zhicheng JING, Jian ZHANG, Guogan ...
2004 Volume 27 Issue 8 Pages
541-544
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
Herpes simplex virus type 2 (HSV-2), which has been recognized as a potential cardiovascular pathogen and implicated in carotid atherosclerosis and coronary artery disease, is independently associated with the future risk of cardiovascular death. Investigations have demonstrated that hypertension may be related to inflammation, and inflammation is one of the symptoms of HSV-2 infection. This cross-sectional study investigated the correlation between HSV-2 infection and essential hypertension. One thousand two hundred and forty four inpatients (488 patients with essential hypertension and 756 normotensives) were investigated serologically for the specific immunoglobulin G (IgG) to HSV-2 by enzyme-linked immunosorbent assay. Patients diagnosed with pheochromocytoma, primary aldosteronism, aorto-arteritis or renal artery stenosis were excluded. The prevalence of HSV-2 IgG seropositivity was significantly higher in the hypertensive group than in the normotensive group (38.3% vs. 29.8%, p =0.002). After adjustment for confounding factors, an association of HSV-2 IgG seropositivity with essential hypertension was found on binary logistic regression analysis. The adjusted odds ratio of essential hypertension was 1.4 (95% confidence intervals, 1.1 to 1.8; p =0.005) for HSV-2 infection; the adjusted covariates included age, male sex, smoking, body mass index, dyslipidemia, diabetes and coronary artery disease. The results of this study indicated that HSV-2 infection might be an independent risk factor for essential hypertension. (Hypertens Res 2004; 27: 541-544)
View full abstract
-
Haruhito UCHIDA, Yoshio NAKAMURA, Masanobu KAIHARA, Taro SUGIMOTO, His ...
2004 Volume 27 Issue 8 Pages
545-550
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
The current guideline-recommended blood pressure values are difficult to maintain in general practice, partly due to the lack of ideal anti-hypertensive agents. Since morning hypertension has a high correlation with cardiovascular events, expectations that telmisartan, a long-acting angiotensin-II type-1 receptor blocker (ARB), can improve cardiovascular mortality are high. In this study, the efficiency of telmisartan in reducing morning hypertension and pulse wave velocity (PWV) as a practical surrogate endpoint was investigated. Seventeen unsupervised and 7 untreated hypertensive patients were prescribed telmisartan 40 mg/day for 3 months. Medication already prescribed upon enrollment in this study was continued, with the exception of ARBs (all of which turned out to be losartan 50 mg/day), which were discontinued and replaced with telmisartan. Morning home blood pressure (MHBP), office blood pressure (OBP), and brachial-ankle PWV (baPWV) were investigated in a prospective fashion. A stratified analysis was performed regarding previous use (group L) or non-use (group N) of losartan. Over a 3-month period, telmisartan was found to significantly reduce both OBP (from 153±13/85±9 to 141±17/80±7 mmHg (p <0.01)) and MHBP (from 153±23/93±11 to 137±22/82±10 mmHg (p <0.001)). Surprisingly, 7 patients (70%) from group L achieved an OBP of less than 140/90 mmHg by simply changing their medication to telmisartan. Furthermore, baPWV fell significantly from 1,892±334 cm/s to 1,672±324 cm/s (p <0.01), which was greater than the change in baPWV estimated by OBP reduction. Here it must be mentioned that there were no significant differences between group L and group N in the courses of blood pressures and baPWV. In conclusion, telmisartan 40 mg/day was found to be effective for reducing MHBP and arterial wall stiffness in patients with mild-to-moderate hypertension, and thus may also be effective for improving cerebrocardiovascular mortality. (Hypertens Res 2004; 27: 545-550)
View full abstract
-
Ken SUGIMOTO, Tomohiro KATSUYA, Takayoshi OHKUBO, Atsushi HOZAWA, Koic ...
2004 Volume 27 Issue 8 Pages
551-556
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
Gene targeting approaches have suggested that the angiotensin II type 1 receptor (AT1R) is involved in blood pressure (BP) regulation and modulation of the effect of angiotensin II. The A1166C polymorphism of the AT1 receptor gene (AT1R/A1166C) is associated with hypertension in Caucasians, but not in Japanese. The goal of this study, the Ohasama Study, was to examine the association between AT1R/A1166C and hypertension, especially home BP, in the Japanese general population. The Ohasama Study was a cohort study based on Japanese rural residents of Ohasama Town in the northern part of Japan. Subjects who gave informed consent to the study protocol and genetic analysis were recruited. Home BP was measured twice in the morning within 1 h of waking up and in the evening just before going to bed. The TaqMan polimerase chain reaction (PCR) method clearly determined AT1R/A1166C genotypes (n =1,207). The genotype distribution of AT1R/A1166C was as follows: AA 84%; AC 15%; CC 1%. There was almost no difference in baseline characteristics among the AT1R genotypes (AA, AC, CC). In the subjects not receiving antihypertensive medication (n =817), both casual BP and home BP were not different among the AT1R genotypes after adjusting for confounding factors (age, sex, body mass index, current smoking habit and current alcohol consumption). The frequency of hypertension showed no difference among AT1R genotypes after adjusting for confounding factors, though the AC and CC genotypes were more frequent in hypertensives than in normotensives. Our data suggested that the AT1R/A1166C polymorphism is not a major genetic predisposing factor for hypertension in Japanese. (Hypertens Res 2004; 27: 551-556)
View full abstract
-
Atsushi HOZAWA, Satoru EBIHARA, Kaori OHMORI, Shinichi KURIYAMA, Takas ...
2004 Volume 27 Issue 8 Pages
557-561
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
To examine the relationship between 8-isoprostane and blood pressure, we measured plasma 8-isoprostane concentration and home blood pressure levels in an elderly Japanese population. Our study population comprised 569 subjects aged 70 years and over who were not receiving antihypertensive medication. On the basis of their blood pressure values, the participants were classified into three groups: normotensive (home blood pressure <135/85 mmHg), hypertensive (home blood pressure 135/85-160/90 mmHg), and severely hypertensive (home blood pressure ≥160/90 mmHg). The mean plasma 8-isoprostane level in the severely hypertensive group (21.1±5.2 pg/ml) was significantly higher than that in the normotensive (20.2±4.9 pg/ml) or hypertensive (19.7±5.1 pg/ml) group, and this result was unchanged when we adjusted for possible confounding factors such as age, sex, use of vitamin A, C or E supplements, smoking status, drinking status, body mass index, use of non-steroidal anti-inflammatory drugs, history of diabetes, hypercholesterolemia, home heart rate and serum creatinine level. Thus, the level of plasma 8-isoprostane appears to be elevated in older subjects with severe hypertension. (Hypertens Res 2004; 27: 557-561)
View full abstract
-
Ken KANAMASA, Norikatsu NAITO, Hideki MORII, Kazue NAKANO, Yasushi TAN ...
2004 Volume 27 Issue 8 Pages
563-572
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
This study was performed to investigate the risk of cardiac events by eccentric or continuous dosing of nitrates in patients with healed myocardial infarction. A total of 573 patients with healed myocardial infarction were assigned to one of two groups: a nitrate-treatment (n =239) and a nontreatment (n =334) group. The nitrate-treatment group was further subdivided into a group receiving eccentric dosing of nitrates (n =153) and a group receiving continuous dosing of nitrates (n =86). The mean observation period was 11.2±8.2 months. The cardiac events investigated were nonfatal and fatal recurrent myocardial infarction, death from congestive heart failure, sudden death, worsening angina and rebound angina. Baseline characteristics were also compared among the three groups to determine any effects on outcome. Among the patients receiving eccentric or continuous dosing of nitrates, the rates of cardiac events were 12.7/1,000 person·year and 67.4/1,000 person·year, respectively, whereas the rate was 19.7/1,000 person·year in the nontreated patients. The incidence of cardiac events was significantly greater in patients receiving continuous dosing of nitrates than in the nontreated patients (p <0.05). Continuous dosing of nitrates thus increases cardiac events, and while eccentric dosing of nitrates does not increase them, it is also not effective at preventing them in patients with healed myocardial infarction. (Hypertens Res 2004; 27: 563-572)
View full abstract
-
Takashi IIDA, Isao KOHNO, Daisuke FUJIOKA, Yoshihide ICHIGI, Ken-ichi ...
2004 Volume 27 Issue 8 Pages
573-579
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
Increased pulse pressure (PP) is recognized as a risk factor for cardiovascular disease, especially in elderly patients. However, blood pressure (BP) is known to have a circadian variation. Therefore, this study asked whether or not PP has a circadian variation and, if so, whether a circadian variation of PP has clinical importance. Ambulatory BP monitoring (every 30 min for 48 h) was performed in 255 patients with untreated essential hypertension (24 to 82 years old; mean: 52±12 years). Left ventricular mass index (LVMI) was estimated from M-mode echocardiography. PP was decreased during nighttime (10±11% reduction from daytime PP). Multivariate linear regression analysis showed that, among four variables—the degree of nighttime PP reduction, daytime PP, 48-h systolic BP, and nondipper hypertension—the degree of nighttime PP reduction had the strongest (inverse) correlation with LVMI in a subgroup of elderly patients (≥60 years old, n =67) (standardized regression coefficient=-0.32, p =0.02), whereas this association was not significant in the whole patient population unclassified by age. Furthermore, a blunted reduction of nighttime PP in combination with nondipper hypertension was an incremental risk for increase in LVMI in the elderly patients. In conclusion, PP is reduced during nighttime, but the degree of reduction varies among patients. The blunted reduction of nighttime PP is a risk for left ventricular hypertrophy, an established predictor of hypertension-induced cardiovascular events, and it may thus play a role in cardiovascular complications, especially in elderly patients with nondipper hypertension. (Hypertens Res 2004; 27: 573-579)
View full abstract
-
Paolo CICCONETTI, Veronica CIOTTI, Laura TAFARO, Carolina PRIAMI, Flav ...
2004 Volume 27 Issue 8 Pages
581-588
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
Several studies have shown a relationship between blood pressure (BP) and cognitive function. Yet very few studies have addressed circadian BP patterns in this context, perhaps due to poor availability of suitable methods to detect slight changes in the cognitive state. Today, brain event-related potentials (ERPs) allow us to detect subclinical changes in cognitive function. We enrolled 30 elderly patients with recently diagnosed hypertension (<2 years) that had never been treated: 18 dippers and 12 nondippers. Patients underwent 24-h ambulatory blood pressure monitoring (ABPM). Careful assessment of their cognitive state was carried out using the mini mental state examination (MMSE), and the recording of P300 and N2 ERPs. No significant differences between the two groups were found. MMSE scores in dippers and nondippers were similar (29.5±0.71 vs. 29.3±1.07, respectively; p =0.611), as were P300 latency values (377.78±33.28 vs. 364.67±35.12 in the central (Cz) position, p =0.310; 379.22±32.94 vs. 365.25±35.07 in the occipital (Pz) position, p =0.277) and N2 wave latency values (253.83±24.9 vs. 249.17±24.47 in the Cz position, p =0.617; 251.56±25.86 vs. 246.58±25.46 in the Pz position, p =0.608). These data show no association between the nondipping pattern and lower cognitive function in elderly subjects with recent hypertension. (Hypertens Res 2004; 27: 581-588)
View full abstract
-
Tetsuya NAKAMURA, Yuichiro SAITO, Yoshio OHYAMA, Tsuyoshi UCHIYAMA, Hi ...
2004 Volume 27 Issue 8 Pages
589-598
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
A mutation of the CD36 gene that encodes a fatty acid transporter has been reported to play a role in insulin resistance in spontaneously hypertensive rat (SHR). Statins reduce circulating cholesterol and triglyceride concentrations. The objective of this study was to determine the role of CD36 and the significance of statin therapy in insulin-resistance syndromes. We determined the isometric relaxation induced by acetylcholine or lecithinized superoxide dismutase (SOD) in aortas obtained from Otsuka Long Evans Tokushima Fatty (OLETF) rats, a model of insulin resistance and dyslipidemia, and normal control (Long Evans Tokushima Otsuka; LETO) rats with or without cerivastatin treatment. We also determined the effect of cerivastatin on aortic expression of CD36 and PPARγ. The CD36 genotype and microsatellite markers on chromosome 4 were also determined. The relaxation induced by acetylcholine and lecithinized SOD were attenuated in OLETF rats but restored by a low dose of cerivastatin without significant changes in serum cholesterol. These relaxations were also restored by a high dose of cerivastatin with significant reductions in serum cholesterol and triglyceride. Cerivastatin increased the aortic expression of CD36 and PPARγ mRNA in both LETO and OLETF rats. However, the basal level of CD36 mRNA and the increase in CD36 mRNA in response to cerivastatin were significantly lower in OLETF rats than in LETO rats. Although the abnormal CD36 genotype reported in SHR was not found in OLETF rats, the microsatellite markers of D4Rat151 and D4Rat115 differed between OLETF and LETO rats. In conclusion, insulin resistance in OLETF rats may be partially due to an altered expression of CD36. Increased aortic expression of CD36 in response to cerivastatin could explain the reduction in serum triglyceride concentrations with statin therapy and may have pronounced beneficial effects in insulin-resistance syndromes. (Hypertens Res 2004; 27: 589-598)
View full abstract
-
Kan SAITO, Nobukazu ISHIZAKA, Toru AIZAWA, Masataka SATA, Naoyuki ISO- ...
2004 Volume 27 Issue 8 Pages
599-607
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
We have previously shown that abnormal iron metabolism might be one underlying mechanism of the renal damage observed in the angiotensin II-infused rat. Transforming growth factor-β1 (TGF-β1) is known to play a crucial role in the development of renal damage induced by activation of the renin-angiotensin-aldosterone system. The purpose of the present study was to examine the effects of an iron chelator and a free radical scavenger on the angiotensin II-induced upregulation of TGF-β1 in the kidney. Rats were given angiotensin II (0.7 mg/kg/day) via osmotic minipumps for 7 days. The expressions of the mRNAs of TGF-β1 and collagen types I and IV were significantly increased in response to angiotensin II treatment. Histologic analysis showed that TGF-β1 expression was upregulated mainly in tubular epithelial cells, and occasionally in glomerular and perivascular cells, some of which were identified as monocytes and/or macrophages. Although tubular cells that overexpressed TGF-β1 did not contain iron particles, angiotensin II-induced TGF-β1 upregulation was suppressed by the iron chelator and the free radical scavenger. The free radical scavenger also suppressed angiotensin II-induced upregulation of heme oxygenase-1, an oxidative-stress sensitive gene. By contrast, administration of iron dextran to rats induced upregulation of TGF-β1 mRNA. Collectively, these data suggest that the renal iron overload and presumed subsequent increase in oxidative stress play a role in angiotensin II-induced upregulation of the mRNAs of TGF-β1 and collagen types I and IV in the kidney. (Hypertens Res 2004; 27: 599-607)
View full abstract
-
Tina GRÖHOLM, Piet FINCKENBERG, Eeva PALOJOKI, Antti SARASTE, Tom ...
2004 Volume 27 Issue 8 Pages
609-618
Published: 2004
Released on J-STAGE: October 19, 2004
JOURNAL
FREE ACCESS
The aim of our study was to compare the cardioprotective effects of vasopeptidase inhibition with those of angiotensin type 1 (AT1)-receptor blockade, a diuretic and the combination of AT1-receptor blockade and a diuretic in an experimental rat model of essential hypertension on a high salt diet. Spontaneously hypertensive rats (SHR) (n =73) were divided into 6 groups to receive the following diet and drug regimens for 8 weeks: 1) low salt controls (NaCl 0.5%); 2) high salt controls (NaCl 6%); 3) omapatrilat (40 mg/kg/d) on a high salt diet; 4) losartan (30 mg/kg/d) on a high salt diet; 5) hydrochlorothiazide (HCTZ; 10 mg/kg/d) on a high salt diet; and 6) losartan+HCTZ (30+10 mg/kg/d) on a high salt diet. Blood pressure was measured by tail-cuff plethysmography. The histological score of myocardial damage, myocardial collagen volume fraction (CVF), connective tissue growth factor (CTGF) expression and cardiomyocyte apoptosis were determined. As an antihypertensive, omapatrilat showed greater efficacy than monotherapy with losartan or HCTZ, and was equally effective as the combination of losartan+HCTZ. Assessed by myocardial damage score, omapatrilat and losartan protected cardiac morphology better than HCTZ or the drug combination. Omapatrilat decreased CVF to a greater extent than the other therapies, whereas losartan was most effective in decreasing CTGF expression. All drug treatments, except HCTZ, decreased cardiomyocyte apoptosis. Our findings provide evidence that both vasopeptidase inhibition and AT1-receptor blockade exert cardioprotective properties beyond their blood pressure-lowering effects. Cardioprotection was associated with prevention of cardiomyocyte apoptosis and inhibition of extracellular matrix formation. (Hypertens Res 2004; 27: 609-618)
View full abstract
