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Yasuaki Hayashino

Publications and source records attributed to Yasuaki Hayashino.

10 recordsLinked to original sources
PubMed2006

Cost-effectiveness of coronary artery disease screening in asymptomatic patients with type 2 diabetes and other atherogenic risk factors in Japan: factors influencing on international application of evidence-based guidelines.

BACKGROUND: Screening for coronary artery disease (CAD) in asymptomatic diabetic patients with atherogenic risk factors is recommended by the American College of Cardiology/American Diabetes Association. It is not clear whether these guidelines apply to the Japanese population with a different epidemiology of CAD. This study evaluates the applicability of the U.S. guidelines to Japan, taking account of cost-effectiveness. DESIGN: A cost-effectiveness analysis using a Markov model was performed to measure the clinical benefit and cost of CAD screening in asymptomatic patients with diabetes and additional atherogenic risk factors. We evaluated cohorts of patients stratified by age, gender, and atherogenic risks. The incremental cost-effectiveness of not screening, exercise electrocardiography, exercise echocardiography, and exercise single-photon emission-tomography (SPECT) was calculated. The data used were obtained from the literature. Outcomes are expressed as US dollars per quality-adjusted life year (QALY). RESULTS: Compared with not screening, the incremental cost-effectiveness ratio (ICER) of exercise electrocardiography was $31,400/QALY for 60-year-old asymptomatic diabetic men, and 46,600 for 65-year-old women with hypertension and smoking. The ICER of exercise echocardiography was $31,500/QALY and of SPECT was $326,000/QALY, compared with the next dominant strategy. Sensitivity analyses found that these results varied according to age, gender, the combination of additional atherogenic risk factors, and the frequency of screening. CONCLUSION: From a societal perspective the U.S. guidelines on screening for CAD in high risk diabetic patients are applicable to the Japanese population. However, the population subjected to screening should be carefully selected to obtain greatest benefit from screening.

Aged↗
PubMed2006

Quality of care associated with number of cases seen and self-reports of clinical competence for Japanese physicians-in-training in internal medicine.

BACKGROUND: The extent of clinical exposure needed to ensure quality care has not been well determined during internal medicine training. We aimed to determine the association between clinical exposure (number of cases seen), self- reports of clinical competence, and type of institution (predictor variables) and quality of care (outcome variable) as measured by clinical vignettes. METHODS: Cross-sectional study using univariate and multivariate linear analyses in 11 teaching hospitals in Japan. Participants were physicians-in-training in internal medicine departments. Main outcome measure was standardized t-scores (quality of care) derived from responses to five clinical vignettes. RESULTS: Of the 375 eligible participants, 263 (70.1%) completed the vignettes. Most were in their first (57.8%) and second year (28.5%) of training; on average, the participants were 1.8 years (range = 1-8) after graduation. Two thirds of the participants (68.8%) worked in university-affiliated teaching hospitals. The median number of cases seen was 210 (range = 10-11400). Greater exposure to cases (p = 0.0005), higher self-reports of clinical competence (p = 0.0095), and type of institution (p < 0.0001) were significantly associated with higher quality of care, using a multivariate linear model and adjusting for the remaining factors. Quality of care rapidly increased for the first 100 to 200 cases seen and tapered thereafter. CONCLUSION: The amount of clinical exposure and levels of self-reports of clinical competence, not years after graduation, were positively associated with quality of care, adjusting for the remaining factors. The learning curve tapered after about 200 cases.

Clinical Competence↗
PubMed2005

Ventilation-perfusion scanning and helical CT in suspected pulmonary embolism: meta-analysis of diagnostic performance.

PURPOSE: To perform meta-analysis of literature about the role of helical computed tomography (CT) and ventilation-perfusion (V-P) scanning in detection of acute pulmonary embolism (PE) by using summary receiver operating characteristic (ROC) curve analysis. MATERIALS AND METHODS: V-P scanning articles published from January 1985 to March 2003 and helical CT articles published from January 1990 to March 2003 in MEDLINE and EMBASE databases were included if (a) tests were performed for evaluation of acute PE, (b) conventional angiography was the reference standard, and (c) absolute numbers of true-positive, false-negative, true-negative, and false-positive results were available. Sensitivity analysis was conducted by excluding articles published before 1995. RESULTS: A total of 12 articles discussing helical CT and/or V-P scanning were included. With a random-effects model, pooled sensitivity for helical CT was 86.0% (95% confidence interval [CI]: 80.2%, 92.1%), and specificity was 93.7% (95% CI: 91.1%, 96.3%). V-P scanning yielded low sensitivity of 39.0% (95% CI: 37.3%, 40.8%) but high specificity of 97.1% (95% CI: 96.0%, 98.3%) with high probability threshold. V-P scanning yielded high sensitivity of 98.3% (95% CI: 97.2%, 99.5%) and low specificity of 4.8% (95% CI: 4.7%, 4.9%) with normal threshold. Regression coefficients for helical CT angiography were 0.588 (95% CI: -1.55, 2.74) and 4.14 (95% CI: -0.002, 8.28) versus V-P scanning with high and normal thresholds, respectively. Regression coefficients for helical CT angiography were 0.588 (95% CI: -1.55, 2.74) and 4.14 (95% CI: -0.002, 8.28) versus V-P scanning with high and normal thresholds, respectively. CONCLUSION: Helical CT has greater discriminatory power than V-P scanning with normal and/or near-normal threshold to exclude PE, while helical CT and V-P scanning with high probability threshold had similar discriminatory power in the diagnosis of PE.

Humans↗
PubMed2005

Systematic evaluation and comparison of statistical tests for publication bias.

BACKGROUND: This study evaluates the statistical and discriminatory powers of three statistical test methods (Begg's, Egger's, and Macaskill's) to detect publication bias in meta-analyses. METHODS: The data sources were 130 reviews from the Cochrane Database of Systematic Reviews 2002 issue, which considered a binary endpoint and contained 10 or more individual studies. Funnel plots with observers'agreements were selected as a reference standard. We evaluated a trade-off between sensitivity and specificity by varying cut-off p-values, power of statistical tests given fixed false positive rates, and area under the receiver operating characteristic curve. RESULTS: In 36 reviews, 733 original studies evaluated 2,874,006 subjects. The number of trials included in each ranged from 10 to 70 (median 14.5). Given that the false positive rate was 0.1, the sensitivity of Egger's method was 0.93, and was larger than that of Begg's method (0.86) and Macaskill's method (0.43). The sensitivities of three statistical tests increased as the cut-off p-values increased without a substantial decrement of specificities. The area under the ROC curve of Egger's method was 0.955 (95% confidence interval, 0.889-1.000) and was not different from that of Begg's method (area=0.913, p=0.2302), but it was larger than that of Macaskill's method (area=0.719, p=0.0116). CONCLUSION: Egger's linear regression method and Begg's method had stronger statistical and discriminatory powers than Macaskill's method for detecting publication bias given the same type I error level. The power of these methods could be improved by increasing the cut-off p-value without a substantial increment of false positive rate.

Linear Models↗
PubMed2004

Outcome and risk factors of de novo autoimmune hepatitis in living-donor liver transplantation.

BACKGROUND: Graft dysfunction mimicking autoimmune hepatitis (AIH) develops only rarely after liver transplantation for nonautoimmune liver disease. The long-term prognosis and risk factors of de novo AIH after living-donor liver transplantation (LDLT) are unknown. METHODS: We review our LDLT series to investigate the incidence and outcome of this form of graft dysfunction, focusing on follow-up histology. RESULTS: Of 633 patients who underwent LDLT at Kyoto University from 1990 to 2002, 13 (2.1%) developed graft dysfunction with interface hepatitis resembling AIH (2 males, 11 females). The median age at LDLT of these 13 patients was 10 years (8 months to 26 years). All received tacrolimus-based immunosuppression. The dysfunction presented at a median interval of 3.1 (0.7-9.5) years after LDLT. Nine had definite AIH, and four had probable AIH at the onset of hepatitis. Patients were followed after a median of 3.5 (0.1-8) years from the onset of de novo AIH. Of 11 patients who underwent follow-up histologic evaluation, 3 underwent retransplantation, and 8 continued to have similar findings on subsequent biopsies, with fluctuations in the amount of necroinflammatory activity and an increase in fibrosis despite treatment. In a multivariate analysis, acute rejection episodes and recipient age between 11 and 15 years at LDLT independently had predictive value for the development of de novo AIH. Human leukocyte antigen-A, B, and DR mismatches and sex mismatch did not influence the occurrence of de novo AIH. CONCLUSION: This series highlights the more severe histologic outcome of de novo AIH with longer follow-up despite immunosuppressive treatment. De novo AIH may arise from alloimmunologic injury, marked by clinically obvious episodes of acute rejection.

Adolescent↗
PubMed2004

Is B-type natriuretic peptide-guided heart failure management cost-effective?

BACKGROUND: Chronic heart failure (CHF) is a common medical problem and B-type natriuretic peptide (BNP)-guided heart failure management for outpatients with symptomatic CHF was found to reduce the readmission rate and mortality, but the costs of treatment may provoke concern in the current cost-conscious clinical setting. METHODS: We conducted a cost-effectiveness analysis using a Markov model of regular BNP measurement in the outpatient setting. The target population was symptomatic CHF patients aged 35-85 years recently discharged from the hospital. Intervention was BNP measurement once every 3 months (BNP group) or no BNP measurement (clinical group). Clinical and utility data were retrieved from published studies. Costs were based on published data in the US. Cost-effectiveness was measured by $ per quality-adjusted life year (QALY). RESULTS: The baseline analysis during the 9-month period after hospitalization showed the QALY to be longer for the BNP group (0.57 for the BNP group and 0.55 for the clinical group) and the costs were also lower for the BNP group ($9577 and 10,131). The dominance of the BNP group continued during the 1-year follow-up. The incremental costs would be $3491-7787 per QALY. In sensitivity analyses, two parameters with strong effects on the cost-effectiveness were the probability of the first readmission for CHF in the clinical group and the costs for inpatient CHF care. When these two parameters were simultaneously put on the simulation model, the incremental costs of the BNP group may exceed $50,000. CONCLUSIONS: Introduction of BNP measurement in heart failure management may be cost-effective.

Adult↗
PubMed2004

Cost-effectiveness of screening for coronary artery disease in asymptomatic patients with Type 2 diabetes and additional atherogenic risk factors.

OBJECTIVE: Screening for coronary artery disease (CAD) in asymptomatic diabetic patients with two additional atherogenic risk factors has been recommended by the American College of Cardiology/American Diabetes Association, but its cost-effectiveness is yet to be determined. The present study aims to evaluate the cost-effectiveness of screening and determine acceptable strategies. DESIGN: Cost-effectiveness analysis using a Markov model was performed from a societal perspective to measure the clinical benefit and economic consequences of CAD screening in asymptomatic men with diabetes and two additional atherogenic risk factors. We evaluated cohorts of patients stratified by different age groups, and 10 possible combination pairs of atherogenic risks. Incremental cost-effectiveness of no screening, exercise electrocardiography, exercise echocardiography, or exercise single-photon emission-tomography (SPECT) was calculated. Input data were obtained from the published literature. Outcomes were expressed as U.S. dollars per quality-adjusted life-year (QALY). MEASUREMENTS AND MAIN RESULTS: Compared with no screening, incremental cost-effectiveness ratio of exercise electrocardiography was $41,600/QALY in 60-year-old asymptomatic diabetic men with hypertension and smoking, but was weakly dominated by exercise echocardiography. Exercise echocardiography was most cost-effective, with an incremental cost-effectiveness ratio of $40,800/QALY. Exercise SPECT was dominated by other strategies. Sensitivity analyses found that results varied depending on age, combination of additional atherogenic risk factors, and diagnostic test performance. CONCLUSIONS: Incremental cost-effectiveness ratio of CAD screening in asymptomatic patients with diabetes and two or more additional atherogenic risk factors is shown to be acceptable from a societal perspective. Exercise echocardiography was the most cost-effective strategy, followed by exercise electrocardiography.

Aged↗
PubMed2004

E148Q/M694I mutation in 3 Japanese patients with familial Mediterranean fever.

We describe 3 unrelated Japanese patients with familial Mediterranean fever (FMF) due to a compound heterozygous E148Q/M694I mutation in the MEFV gene. The first patient is a 38-year-old man who also has chronic myelogenous leukemia (CML). Because genomic DNA analysis of the patient's nail revealed the E148Q/M694I mutation, we concluded that the individual mutations were obtained congenitally. Interferon alpha therapy was effective against not only the CML but also the FMF. The second patient is a 42-year-old man with consanguineous parents and a 14-year history of recurrent lower abdominal and back pain associated with fever. He successfully responded to colchicine treatment. The third patient is a 23-year-old woman who has a family history of FMF and since the age of 11 years has had recurrent chest and abdominal pain with fever. The onset of FMF was at an early age in this case, in contrast with the late onset of the disease in the first 2 cases. This patient's mother also has a heterozygous M694I mutation and experienced the same symptoms until 30 years of age. Our data suggest that it should be recognized that there are more FMF patients in Japan than previously expected and that the frequency of the E148Q/M694I mutation may be significant in Japanese FMF patients.

Adult↗
PubMed2003

Japan's contribution to research on cardiovascular disease.

Japan's contribution to the research on cardiovascular disease in the past decade was analyzed by accessing journal articles published in 1991-2000 in the MEDLINE database. The number of articles having an affiliation with a Japanese institution was counted and summed up as a whole and also separately for each journal with statistical time trend analysis. The proportions of randomized controlled study (RCT), case - control/cohort study, and case reports in articles from Japan were also determined. Of the total articles, Japan's contribution to the research on cardiovascular disease was 8.9% and ranked 2nd in the world. The recent increase in the contribution was not significant (p=0.25). Compared with other countries, the proportions of RCT (2.3%) and case - control/cohort study (2.3%) were smaller and that of case reports was similar (5.7%). Although the overall contribution from Japan in the field of cardiovascular disease is satisfactory, high-quality clinical research is as meager as in other clinical fields.

Biomedical Research↗