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Featured researches published by Toshiaki Otsuka.


American Heart Journal | 2010

Association between high-sensitivity cardiac troponin T levels and the predicted cardiovascular risk in middle-aged men without overt cardiovascular disease

Toshiaki Otsuka; Tomoyuki Kawada; Chikao Ibuki; Yoshihiko Seino

BACKGROUND A slight elevation of cardiac troponin T (TnT) levels in the circulating blood can be detected by the recently developed, high-sensitivity TnT (hsTnT) assay. However, it remains unclear whether a slight elevation of hsTnT is associated with an increased cardiovascular risk in subjects without overt cardiovascular disease (CVD). METHODS The serum hsTnT levels were measured in a work site-based population of 1,072 middle-aged males (mean age 44 years) without any history or presence of CVD. The lower detection limit of the hsTnT assay used in the present study was 0.002 ng/mL. The association of the hsTnT levels with cardiovascular risk factors and the predicted CVD risk, as determined by the Framingham CVD risk prediction score, were examined. RESULTS Detectable hsTnT levels were seen in 867 subjects (80.9%). The highest value of the hsTnT was 0.020 ng/mL. Among various cardiovascular risk factors, age, blood pressure, estimated glomerular filtration rate, current smoking, and left ventricular hypertrophy were independent determinants of hsTnT levels. The odds ratio for a high predicted CVD risk (10-year risk > or =20%) in the highest tertile of hsTnT (> or =0.005 ng/mL) in comparison to the lowest tertile (< or =0.002 ng/mL) was 3.98 (95% CI 1.72-9.24, P = .001) after adjusting for multiple potential confounders. CONCLUSIONS The present study showed the hsTnT levels to be significantly associated with several cardiovascular risk factors and the predicted CVD risk in middle-aged men without overt CVD, thus suggesting the usefulness of measuring hsTnT to identify high-risk subjects in the primary prevention of CVD.


Circulation-cardiovascular Interventions | 2014

Clinical Outcomes and Safety of Transfemoral Aortic Valve Implantation Under General Versus Local Anesthesia Subanalysis of the French Aortic National CoreValve and Edwards 2 Registry

Atsushi Oguri; Masanori Yamamoto; Gauthier Mouillet; Martine Gilard; Marc Laskar; Hélène Eltchaninoff; Jean Fajadet; Bernard Iung; Patrick Donzeau-Gouge; Pascal Leprince; Alain Leguerrier; Alain Prat; Michel Lievre; Karine Chevreul; Jean-Luc Dubois-Randé; Romain Chopard; Eric Van Belle; Toshiaki Otsuka; Emmanuel Teiger

Background—Transcatheter aortic valve implantation (TAVI) performed under local anesthesia (LA) is becoming increasingly common. We aimed to compare the clinical outcomes in patients who underwent transfemoral-TAVI under general anesthesia (GA) and LA. Methods and Results—Data from 2326 patients in the French Aortic National CoreValve and Edwards 2 (FRANCE 2) registry who underwent transfemoral-TAVI were analyzed. During the study period, the percentage of LA procedures increased gradually from 14% in January 2010 to 59% in October 2011. The clinical outcomes for GA (n=1377) and LA (n=949) were compared. Numerous baseline characteristics differed between the 2 groups, and the use of transesophageal echocardiographic guidance was more common in GA than in LA (76.3% versus 16.9%; P<0.001). Device success and cumulative 30-day survival rates were similar in the 2 groups (97.6% versus 97.0%; P=0.41 and 91.6% versus 91.3%; P=0.69, respectively), whereas the incidence of postprocedural aortic regurgitation≥mild was significantly lower in GA than in LA (15.0% versus 19.1%; P=0.015). The groups were also analyzed using a propensity-matching model, including transesophageal echocardiographic usage (GA [n=401] versus LA [n=401]). This model indicated that there were no significant differences between the 2 groups in the rates of 30-day survival (GA [91.4%] versus LA [89.3%]; P=0.27] and postprocedural aortic regurgitation≥mild (GA [12.7%] versus LA [16.2%]; P=0.19). Conclusions—The less invasive transfemoral-TAVI under LA is preferred in clinical settings and seems to be acceptable; however, the higher incidence of postprocedural aortic regurgitation is emphasized. Therapeutic efforts should be made to reduce such complications during transfemoral-TAVI under LA.


Work-a Journal of Prevention Assessment & Rehabilitation | 2011

Relationship between job stress, occupational position and job satisfaction using a brief job stress questionnaire (BJSQ)

Tomoyuki Kawada; Toshiaki Otsuka

OBJECTIVE Subjects with higher occupational position are speculated to have higher ability to handle with stress, and they were less affected by job stress. This study focused on the relationship between job satisfaction and three sub-scales of a brief job stress questionnaire (BJSQ) related to workload. PARTICIPANTS AND METHODS This self-administered questionnaire was distributed to 371 employees of a company, and all the workers sent back their responses. Among the 57 items graded on a 4-point Likert-type scale to measure job stressors, psycho-physical complaints, and support for workers, the authors studied the influence of quantitative and qualitative job overload (six items), job control (three items), and support port (six items). The job satisfaction score estimated on a 4-point Likert-type scale was also used in relation to job stress determined using a 15-item scale from the BJSQ based on demand-control-support model. Occupational positions were classified into directors, managers, and general workers, and the content of job was classified into clerical workers, skilled technicians, and unskilled manual workers. RESULTS All the scales on job stress presented acceptable alpha coefficients reflecting high internal consistency (job demand: 0.855, job control: 0.644, and support: 0.878, respectively). Principal axis factor analysis was conducted, and three factors were extracted; support, job demand and job control. There was a significant difference in the mean score among four groups divided by the job satisfaction level as evaluated by Dunnetts multiple comparison, and members who were dissatisfied with their job showed a high job demand, limited job control, and poor support. The mean score of support for managers were significantly higher (lower support) than that for general workers. The logistic regression analysis revealed that job control and support contributed significantly to job satisfaction. In addition, unskilled manual workers showed significantly higher job dissatisfaction compared with clerical workers. CONCLUSIONS Worsening of job satisfaction was related to poor job control and lack of support. Strategies to alleviate job stress are therefore urgently needed.


Circulation | 2017

Impact of the Clinical Frailty Scale on Outcomes After Transcatheter Aortic Valve Replacement

Tetsuro Shimura; Masanori Yamamoto; Seiji Kano; Ai Kagase; Atsuko Kodama; Yutaka Koyama; Etsuo Tsuchikane; Takahiko Suzuki; Toshiaki Otsuka; Shun Kohsaka; Norio Tada; Futoshi Yamanaka; Toru Naganuma; Motoharu Araki; Shinichi Shirai; Yusuke Watanabe; Kentaro Hayashida

Background: The semiquantitative Clinical Frailty Scale (CFS) is a simple tool to assess patients’ frailty and has been shown to correlate with mortality in elderly patients even when evaluated by nongeriatricians. The aim of the current study was to determine the prognostic value of CFS in patients who underwent transcatheter aortic valve replacement. Methods: We utilized the OCEAN (Optimized Catheter Valvular Intervention) Japanese multicenter registry to review data of 1215 patients who underwent transcatheter aortic valve replacement. Patients were categorized into 5 groups based on the CFS stages: CFS 1-3, CFS 4, CFS 5, CFS 6, and CFS ≥7. We subsequently evaluated the relationship between CFS grading and other indicators of frailty, including body mass index, serum albumin, gait speed, and mean hand grip. We also assessed differences in baseline characteristics, procedural outcomes, and early and midterm mortality among the 5 groups. Results: Patient distribution into the 5 CFS groups was as follows: 38.0% (CFS 1-3), 32.9% (CFS4), 15.1% (CFS 5), 10.0% (CFS 6), and 4.0% (CFS ≥7). The CFS grade showed significant correlation with body mass index (Spearman’s &rgr;=−0.077, P=0.007), albumin (&rgr;=−0.22, P<0.001), gait speed (&rgr;=−0.28, P<0.001), and grip strength (&rgr;=−0.26, P<0.001). Cumulative 1-year mortality increased with increasing CFS stage (7.2%, 8.6%. 15.7%, 16.9%, 44.1%, P<0.001). In a Cox regression multivariate analysis, the CFS (per 1 category increase) was an independent predictive factor of increased late cumulative mortality risk (hazard ratio, 1.28; 95% confidence interval, 1.10–1.49; P<0.001). Conclusions: In addition to reflecting the degree of frailty, the CFS was a useful marker for predicting late mortality in an elderly transcatheter aortic valve replacement cohort.


Journal of the Neurological Sciences | 2010

Asymmetric dimethylarginine (ADMA) as a possible risk marker for ischemic stroke

Yasuhiro Nishiyama; Masayuki Ueda; Ken-ichiro Katsura; Toshiaki Otsuka; Arata Abe; Hiroshi Nagayama; Yasuo Katayama

BACKGROUND Asymmetric dimethylarginine (ADMA) affects vascular function by blocking nitric oxide synthesis. We examined the relationship of ADMA concentration to vascular risk factors in subjects who have undergone annual medical check-up. METHODS ADMA concentration, lipid profile and vascular risk factors were assessed during an annual medical examination in 116 subjects (mean age 58.7years). Univariate and multivariate analyses were carried out to assess factors associated with ADMA concentration. ADMA concentration was also assessed in 50 age-matched patients with ischemic stroke. RESULTS Mean serum ADMA concentration was significantly higher in the ischemic stroke patients than the medical check-up subjects (0.461+/-0.076 versus 0.433+/-0.056mumol/l; P=0.022). Univariate analysis showed that ADMA concentration in the medical check-up subjects was significantly associated with age, hypertension, dyslipidemia, fasting blood glucose, total and LDL cholesterol concentrations. Multiple stepwise linear regression analysis showed that hypertension (beta=0.25, P=0.008) and dyslipidemia (beta=0.19, P =0.048) were significant independent determinants of ADMA concentration. ADMA concentration increased progressively with number of vascular risk factors, with a significant (P=0.001) difference between subjects with no risk factors and subjects with > or =2 risk factors. CONCLUSIONS Serum ADMA concentration was significantly associated with vascular risk factors in subjects undergoing routine medical check-up. ADMA concentration warrants further examination as a possible marker of future development of ischemic stroke.


Coronary Artery Disease | 2008

Administration of the Rho-kinase inhibitor, fasudil, following nitroglycerin additionally dilates the site of coronary spasm in patients with vasospastic angina

Toshiaki Otsuka; Chikao Ibuki; Takeshi Suzuki; Kensuke Ishii; Hiroshi Yoshida; Eitaro Kodani; Yoshiki Kusama; Hirotsugu Atarashi; Hiroshi Kishida; Teruo Takano; Kyoichi Mizuno

BackgroundThe Rho/Rho-kinase signaling pathway is known to be involved in the pathogenesis of coronary artery spasm. Previous studies reported the efficacy of the Rho-kinase inhibitor, fasudil, in the prevention and relief of coronary spasm. The usefulness of fasudil in combination with conventional vasodilating agents, however, has not been fully examined in patients with vasospastic angina. Methods and resultsA total of 26 patients (mean age, 61±11 years) with documented vasospasm in the left anterior descending coronary artery were examined by the acetylcholine stress test. Coronary diameter at the spasm site was measured at baseline and after the administration of vasodilator agents in the following order: intracoronary nitroglycerin (NTG) (300 μg), intravenous fasudil (30 mg, n=15, fasudil group) or saline (n=11, saline group), and again NTG during coronary angiography. The increase in diameter observed following the first NTG administration was found to be similar in the fasudil and saline groups (38.3±23.5% and 42.3±17.1%, respectively). The additional change in diameter on fasudil treatment (16.9±11.2% increase over the diameter after the first NTG administration) was significantly larger than that with saline (−2.8±7.6%, P<0.001). The second administration of NTG did not affect the diameter of the spasm site in either group. ConclusionsFasudil further dilated the site of coronary spasm, which had already been treated with NTG in patients with vasospastic angina. These findings support and extend the previous results that showed the feasibility of employing fasudil as a novel therapeutic approach for coronary spasm.


Obesity Research & Clinical Practice | 2010

Association of smoking status, insulin resistance, body mass index, and metabolic syndrome in workers: A 1-year follow-up study

Tomoyuki Kawada; Toshiaki Otsuka; Hirofumi Inagaki; Yoko Wakayama; Qing Li; Ying-Ji Li; Masao Katsumata

SUMMARY OBJECTIVE We performed a 1-year follow-up study to determine the effects of smoking status and insulin resistance on the prevalence of metabolic syndrome. METHODS This study included 2136 workers without metabolic syndrome at baseline who were followed for 1 year. The subjects were divided into four categories of smoking and work history, respectively. Insulin resistance was evaluated using the homeostasis model assessment for insulin resistance (HOMA-R). RESULTS The prevalence of metabolic syndrome after 1 year was 6.3%. A multiple logistic regression analysis showed that the current smokers category versus the non-smokers category, a 0.1-point increase in the HOMA-R score, a 1-point increase in the uric acid level, age, and body mass index were significantly correlated with increased odds for metabolic syndrome, yielding odds ratios (95% confidence intervals) of 1.61 (1.09-2.39), 1.14 (1.04-1.25), 1.31 (1.12-1.54), and 1.06 (1.03-1.09), and 1.23 (1.15-1.31), respectively. CONCLUSIONS Current smoking, insulin resistance, uric acid level, and age contributed positively to the prevalence of metabolic syndrome. In contrast, smoking cessation within 1 year and work history did not contribute to metabolic syndrome.


American Journal of Cardiology | 2010

Relation of Smoking Status to Serum Levels of N-Terminal Pro-Brain Natriuretic Peptide in Middle-Aged Men Without Overt Cardiovascular Disease

Toshiaki Otsuka; Tomoyuki Kawada; Yoshihiko Seino; Chikao Ibuki; Masao Katsumata; Eitaro Kodani

Cigarette smoking impairs arterial function and promotes atherosclerosis. However, whether smoking status is associated with cardiac overload has not yet been fully examined, particularly from an epidemiologic viewpoint. The present study examined the relation of smoking status to serum levels of N-terminal pro-brain natriuretic peptide (NT-pro-BNP), a marker of cardiac overload, in middle-aged men without overt cardiovascular disease. Serum NT-pro-BNP levels were measured in a work-site based population of 969 men (mean age 44 ± 6 years) who did not have any history or presence of cardiovascular disease. Smoking status was evaluated by self-reported questionnaire. Four hundred fifty-nine, 222, and 288 subjects were never, former, and current smokers, respectively. NT-pro-BNP levels were significantly higher in current smokers (21.7 ± 2.3 pg/ml) than in never smokers (17.9 ± 2.1 pg/ml, p <0.001). This significant difference was maintained even after adjusting for age, obesity, heart rate, hypertension, dyslipidemia, impaired fasting glucose/diabetes mellitus, left ventricular hypertrophy, estimated glomerular filtration rate, high-sensitivity C-reactive protein, alcohol consumption, and regular exercise. Current smokers had an increased odds ratio (3.04, 95% confidence interval 1.64 to 5.61, p <0.001) for elevated NT-pro-BNP (>54.5 pg/ml) compared to never smokers, even after adjusting for the studied variables. In contrast, former smokers did not show a significantly increased odds ratio for elevated NT-pro-BNP. NT-pro-BNP levels showed a weak, but significant negative correlation with duration of smoking cessation (partial r = -0.15, p = 0.034) in former smokers. In conclusion, these results suggest that cigarette smoking increases cardiac overload, whereas smoking cessation ameliorates these conditions.


Scandinavian Journal of Work, Environment & Health | 2014

Precarious employment and the risk of serious psychological distress: a population-based cohort study in Japan.

Yuko Kachi; Toshiaki Otsuka; Tomoyuki Kawada

OBJECTIVES This study examines whether precarious employment increases the risk of serious psychological distress (SPD) in a nationally representative cohort of Japanese middle-aged people. METHODS From 2005-2009, we followed 8486 male and 6736 female participants (aged 50-59 years) in the Longitudinal Survey of Middle-aged and Elderly Persons. All individuals were employed and free of SPD, cardiovascular disease, and cancer at baseline. The participants were classified into two groups based on their baseline employment contract: precarious and full-time permanent work. SPD was assessed at each year during the study, using the K6 scale, a self-rated 6-item scale that screens for mood or anxiety disorders. We used discrete-time survival analysis, with a complementary log-log link, to examine the effect of precarious employment on SPD incidence. RESULTS During a maximum follow-up period of four years, 374 men and 364 women developed SPD. Male precarious employees were more likely to develop SPD than male full-time permanent employees (hazard ratio 1.79, 95% confidence interval 1.28-2.51) in the full model, after adjusting for sociodemographic and occupational factors, cardiovascular disease risk, and K6 scores at baseline. By contrast, no significant association was observed among female employees. However, an analysis stratified by marital status revealed an association similar to that found among men but only among unmarried women. CONCLUSIONS The findings suggest that precarious employment is associated with double the risk of SPD incidence among middle-aged Japanese men and - when stratified by marital status - among unmarried women. This highlights a major gender difference in the association between precarious employment and risk of SPD.


Hypertension Research | 2007

Independent Determinants of Second Derivative of the Finger Photoplethysmogram among Various Cardiovascular Risk Factors in Middle-Aged Men

Toshiaki Otsuka; Tomoyuki Kawada; Masao Katsumata; Chikao Ibuki; Yoshiki Kusama

The second derivative of the finger photoplethysmogram (SDPTG) has been used as a non-invasive examination for arterial stiffness. The present study sought to elucidate independent determinants of the SDPTG among various cardiovascular risk factors in middle-aged Japanese men. The SDPTG was obtained from the cuticle of the left-hand forefinger in 973 male workers (mean age: 44±6 years) during a medical checkup at a company. The SDPTG indices (b/a and d/a) were calculated from the height of the wave components. Multiple logistic regression analyses revealed that the independent determinants of an increased b/a (highest quartile of the b/a) were age (odds ratio [OR]: 1.12 per 1-year increase, 95% confidence interval [CI]: 1.09–1.15), hypertension (OR: 1.65, 95% CI: 1.03–2.65), dyslipidemia (OR: 1.51, 95% CI: 1.09–2.09), impaired fasting glucose/diabetes mellitus (OR: 2.43, 95% CI: 1.16–5.07), and a lack of regular exercise (OR: 2.00, 95% CI: 1.29–3.08). Similarly, independent determinants of a decreased d/a (lowest quartile of the d/a) were age (OR: 1.11 per 1-year increase, 95% CI: 1.08–1.14), hypertension (OR: 3.44, 95% CI: 2.20–5.38), and alcohol intake 6 or 7 days per week (OR: 2.70, 95% CI: 1.80–4.06). No independent association was observed between the SDPTG indices and blood leukocyte count or serum C-reactive protein levels. In conclusion, the SDPTG indices reflect arterial properties affected by several cardiovascular risk factors in middle-aged Japanese men. The association between inflammation and the SDPTG should be evaluated in further studies.

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Qing Li

Nippon Medical School

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