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Yasuyuki Okumura

Yasuyuki Okumura
Initiative for Clinical Epidemiological Research

PhD

About

79
Publications
7,361
Reads
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923
Citations
Citations since 2016
46 Research Items
755 Citations
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2016201720182019202020212022020406080100120140
2016201720182019202020212022020406080100120140
2016201720182019202020212022020406080100120140
Introduction
Additional affiliations
April 2013 - present
Institute for Health Economics and Policy
Institute for Health Economics and Policy
May 2008 - March 2013
National Center of Neurology and Psychiatry
April 2006 - March 2009
Nihon University

Publications

Publications (79)
Article
Full-text available
Objectives Validation studies in oncology are limited in Japan. This study was conducted to evaluate the accuracy of diagnosis and adverse event (AE) definitions for specific cancers in a Japanese health administrative real-world database (RWD). Design and setting Retrospective observational validation study to assess the diagnostic accuracy of el...
Article
Background: Inadequate postoperative analgesia has been noted in patients with dementia, but this topic has only been studied in hip fractures. This study aimed to examine whether the duration of postoperative analgesia associated with three surgical procedures was shorter in patients with dementia than in those without dementia. Methods: This r...
Article
Context The growing number of older people significantly affects end-of-life care. However, few studies have assessed the quality of end-of-life care among cancer patients with dementia. Objectives To assess the quality of end-of-life care among non-small cell lung cancer patients with or without dementia using a nationwide inpatient database from...
Article
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Background: The association of insomnia treatment with medical costs is not well characterized in Japan, despite the high economic burden of insomnia. Objective: The aim of this study was to investigate the impact of suvorexant, the first dual orexin receptor antagonist, on direct medical costs in insomnia patients. Patients and methods: This...
Article
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Background The efficacy of the unified protocol of the transdiagnostic treatment for emotional disorders (UP) has been poorly studied in patients with depressive disorders. This study aimed to examine the efficacy of UP for improving depressive symptoms in patients with depressive and/or anxiety-related disorders. Methods This assessor-blinded, ra...
Article
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Background: Suicide remains one of the leading causes of death among adolescents. Although recent studies have suggested a strong association between auditory hallucinations and suicidal behaviors, little is known regarding the association between suicidal behaviors and visual hallucinations, which are also common among adolescent psychiatric pati...
Article
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Purpose: Routinely collected data are useful for epidemiological study in hemophilia, but few studies validated the algorithm accuracy. We aimed to develop and validate algorithms to identify patients with hemophilia A and hemophilia A-related events. Patients and methods: This validation study compared data from medical chart reviews to a datab...
Article
Long-acting injectable antipsychotics (LAI-APs) remain underutilized. One reason is the concern that LAI-APs might cause serious adverse events such as neuroleptic malignant syndrome (NMS) and lead to prolonged symptoms compared with oral treatment. Because the risk of NMS associated with LAI second-generation antipsychotics (LAI-SGAs) remains uncl...
Article
Background Little is known about how behavioral health (BH) conditions affect health care costs of cancer patients in Japan. Objective The purpose of this study is to evaluate the magnitude of general medical claims expenditures for individuals with cancer who use or do not use BH services in Japan. Methods The study used a health insurance claim...
Article
Objectives: To evaluate the magnitude of general medical claims expenditures (ie, medical service use) for individuals who use and do not use behavioral health (BH) services in the Japanese free-access medical insurance system to determine if BH patients use substantially more health services, as has consistently been reported in the United States...
Article
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Introduction: For assessing personal values, the rating scale method may not adequately reflect the hierarchical structure of personal values and tends to be influenced by response style bias. The paired comparison method is considered a promising alternative approach, because it engages comparative judgment and may reduce response style biases. T...
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We aimed to assess the efficacy of a reablement program in improving the independence from long-term care services of older adults with mild disability. This parallel, two-arm, randomized controlled, superiority trial was conducted in Neyagawa, a local government area in Osaka, Japan. Eligible participants were community-dwelling individuals aged ≥...
Article
Many patients in mental health settings are likely to have histories of interpersonal traumatic experiences. Mental health providers are recommended to adopt trauma‐informed care (TIC) to ensure sensitivity and responsiveness to the impact of trauma on patients. However, few studies have examined the effectiveness of a TIC training programme using...
Article
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Objective: To describe the psychosocial functioning in children with undiagnosed persistent ADHD symptoms. Method: A prospective, population-based birth cohort study was conducted among 2,945 children and their primary caregivers who lived in Tokyo, Japan, and were followed up at the age of 10 years and 12 years. Parents reported a history of ADHD...
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Background: We evaluated whether the DELirium Team Approach (DELTA) program-a systematic management program aimed at screening high-risk groups and preventing delirium-would improve quality of care in patients hospitalized with cancer. Methods: A retrospective before-after study was conducted during a pre-intervention period (between October 201...
Article
Background: Anxiety disorders are prevalent among adolescents; however, without objective behavioral markers, anxiety disorders in adolescent populations may often go undiagnosed. Response inhibition is considered as a possible behavioral marker, based on the results with two-gate design, which can aid in early detection of anxiety disorders. The a...
Article
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The study objective was to investigate the association between timely follow-up visits after psychiatric hospitalization and the risk of readmission in patients with schizophrenia or bipolar disorder. A retrospective cohort study was conducted using a nationwide claims database in Japan. Between April 2014 and March 2015, all psychiatric hospitaliz...
Article
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Background: Understanding the area-specific resource use of inpatient psychiatric care is essential for the efficient use of the public assistance system. This study aimed to assess the geographical variation in psychiatric admissions and to identify the prefecture-level determinants of psychiatric admissions among recipients of public assistance i...
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Background: A better understanding of resource use of new psychiatric admissions is important for healthcare providers and policymakers to improve psychiatric care. This study aims to describe the pattern of new psychiatric admissions and length of stay in Japan. Methods: A retrospective cohort study was conducted using data from the National Datab...
Article
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Purpose Treatable causes of cognitive dysfunction, such as hypothyroidism, should be excluded by physicians before prescribing anti-dementia drugs. Many clinical guidelines for dementia recommend a thyroid function test (TFT) as one of the standard screening tests for cognitive dysfunction. This study aimed to investigate the national implementatio...
Article
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Objective: We aimed to evaluate glucose and prolactin monitoring in children and adolescents initiating antipsychotic therapy using a nationwide claims database. Methods: A retrospective 15-month cohort study was conducted using the National Database of Health Insurance Claim Information and Specified Medical Checkups in Japan. Patients aged ≤18...
Article
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Prevalence, incidence and persistence of ADHD drug use in Japan - Y. Okumura, M. Usami, T. Okada, T. Saito, H. Negoro, N. Tsujii, J. Fujita, J. Iida
Article
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Background The effects of psychiatrist staffing are unclear. The aim of this study was to assess the association of high psychiatrist staffing with prolonged hospitalization, follow-up visits, and readmission in acute psychiatric units. Methods A retrospective cohort study was conducted using the National Database of Health Insurance Claim Informa...
Article
Objectives: To assess the association between dementia and risk of hospital readmission and to evaluate whether the effect of dementia on hospital readmission varies according to primary diagnosis. Design: Retrospective cohort study. Setting: Nationwide discharge database of acute care hospitals in Japan. Participants: Individuals aged 65 an...
Article
Background In April 2016, the Japanese government introduced an additional benefit for dementia care in acute care hospitals (dementia care benefit) into the universal benefit schedule of public healthcare insurance program. The benefit includes a financial disincentive to use physical restraint. The present study investigated the association betwe...
Article
Background: Suicidal behavior accounts for at least 40,000 admissions per year to emergency departments in Japan; however, little is known about emergency admissions owing to suicidal behavior in metropolitan areas. Therefore, we examined the clinical characteristics of suicidal behavior using psychosocial assessments performed by experienced psyc...
Article
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Early-onset dementia (EOD) affects the employment of patients and family members. To demonstrate how likely employees are to leave their jobs after an EOD diagnosis for themselves or a family member, we conducted a matched cohort study of 143 employees and 77 family members diagnosed with EOD using a claims database. We matched these participants t...
Article
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Objective We aimed to estimate risk of recurrent overdose associated with psychosocial assessment by psychiatrists during hospitalization for nonfatal overdose and prescribing patterns of psychotropic medications after discharge. Methods A retrospective cohort study was conducted using a nationwide claims database in Japan. We classified patients...
Article
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Background The feasibility of shared decision making (SDM) for patients with schizophrenia remains controversial due to the assumed inability of patients to cooperate in treatment decision making. This study evaluated the feasibility and efficacy of SDM in patients upon first admission for schizophrenia. Methods This was a randomized, parallel-grou...
Article
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Background: Little is known about the nationwide epidemiology of the annual rate, causative substance, and clinical course of overdose-related admission. We aimed to describe the epidemiology of overdose episodes from the period prior to hospitalization for drug poisoning until discharge to home. Methods: We assessed all cases of admission due t...
Article
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Conclusions of randomized controlled trials are frequently distorted by authors of articles. Such a misleading reporting practice is called “spin”. In the present article, I aimed to (1) review three trials with spin that have significant implications for clinical practices in Japan, (2) review a retracted article due to spin and discuss an editori...
Article
Aim: The aim of our study is to clarify the geographical movement of patients treated in psychiatric facilities, which can provide important information on the resources and healthcare system of psychiatric services. Methods: We conduct an analysis of nationwide data on psychiatric patients, collected as an additional survey to the conventional...
Article
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Objectives Some patients with deliberate drug poisoning subsequently have an adverse clinical course. The present study aimed to examine whether the type of drugs ingested and psychiatric diagnoses were related to an adverse clinical course. Methods We conducted a cohort study of patients with deliberate drug poisoning admitted to the intensive ca...
Article
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Background The unified protocol for the transdiagnostic treatment of emotional disorders is a promising treatment approach that could be applicable to a broad range of mental disorders, including depressive, anxiety, trauma-related, and obsessive-compulsive disorders. However, no randomized controlled trial has been conducted to verify the efficacy...
Article
Background: There is little expert consensus as to which drugs should comprise the first-line pharmacological treatment for delirium. We sought to assess experts' opinions on the first-line oral and injection drugs for delirium associated with a diverse range of clinical features using a rating-based conjoint analysis. Methods: We conducted a cr...
Article
Drug overdose is a serious public health issue and fatal cases have been reported from various fields of medicine. This case-control analysis assessed the comparison between fatal overdose cases in the special wards of Tokyo Metropolitan area and prescribed psychotropic drugs in Tokyo in 2009-2010. It was suggested that the prescribed drugs serve a...
Article
Context: Children and adolescents with intellectual disability often have various mental disorders and behaviour problems. Despite the limited evidence on the efficacy and safety of psychotropic medication use to children and adolescents with intellectual disability, clinicians often prescribes psychotropic medications for the management of proble...
Article
Background: Little is known about the use of multiple prescribers for benzodiazepines, which might reflect fragmented patient care and increases the risk of hospital admission for drug dependence or poisoning. Therefore, we aimed to identify the prevalence, prescribed quantities, and trajectory of multiple prescriber episodes for benzodiazepines....
Article
Objective: In 2012, the Japanese Ministry of Health, Labour and Welfare implemented a policy to reduce the prescription of combined anxiolytic-hypnotic drug. In 2014, the policy was strengthened. To determine the effect of the anxiolytic-hypnotic polypharmacy reduction policy on the prescription of high-dose and combined anxiolytic-hypnotic drug in...
Article
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Little is known about psychotropic medication prescriptions prior to drug overdose. We aimed to examine the possible associations between the risk of overdose and exposures to various psychotropic medications. We conducted a matched case-control study of 3 groups of patients aged 12-74 years, using a large-scale health insurance claims database in...
Article
The aim of this study was to investigate whether depression severity was associated with work impairments, regardless of the diagnosis. We conducted a cross-sectional study among 17,820 Japanese workers using an Internet-based survey. Work impairments were assessed using the Work Productivity and Activity Impairment questionnaire. Participants were...
Article
Background: We aimed to examine trends in the use of psychotropic medications among elderly outpatients with dementia in Japan between 2002 and 2010. Methods: We used data from the 2002-2010 Survey of Medical Care Activities in Public Health Insurance (SMCA-PHI), a nationally representative cross-sectional survey of claims data for the month of...
Article
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Shared decision making is a promising model for patient-centred medicine, resulting in better clinical outcomes overall. In the mental health field, interventions that consider the patient-centred perspective--such as patient quality of life, involvement in the treatment, treatment satisfaction, and working alliance--have increased and better clini...
Article
Context: Despite evidence of an increase in the number of young patients receiving mental health treatment, most psychotropic medications have not been approved for the treatment of children and adolescents by the Ministry of Health, Labour and Welfare. There is little data available on psychotropic medication use in children and adolescents in Jap...
Article
Objective: To assess spatial variability in psychotropic polypharmacy among recipients of public assistance. Design: We used pharmacy claims data from the 2011-2012 Fact-finding Survey on Medical Assistance conducted in Japan. Data were collected from all public assistance recipients who received outpatient treatment and obtained prescription medi...
Chapter
Patients with schizophrenia are more likely than the general population to have metabolic syndrome and to live around 15 fewer years largely because of cardiovascular death. Recent studies have suggested that antipsychotic polypharmacy may be associated with metabolic disturbance including metabolic syndrome and the mortality related to it. Althoug...
Article
Although attention has recently been focused on the role of psychosocial factors in patients with cardiovascular disease (CVD), the factors that have the greatest influence on prognosis have not yet been elucidated. The aim of this study was to evaluate the effects of depression, anxiety, and anger on the prognosis of patients with CVD. Four hundre...
Article
Objectives: This study aimed to estimate the prevalence of psychological distress in individuals with and without cardiovascular risks and events [cardiovascular disease (CVD) conditions] and the incremental effects of psychological distress on the out-of-pocket health care expenditure burdens. Methods: We used data from the Comprehensive Survey...
Article
Objective: The present study aimed to assess antipsychotic prescribing patterns in a representative sample of patients with schizophrenia in Japan. Method: The stratified sampling dataset of the National Database of Health Insurance Claim Information and Specified Medical Checkups was used to obtain data on antipsychotic medications in October 201...
Article
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To compare the clinical and procedural characteristics of emergency hospital admissions for drug poisoning and major diseases. Retrospective observational study. Discharged patients from 855 acute care hospitals from 1 July to 31 December in 2008 in Japan. There were a total of 1 157 893 emergency hospital admissions. Among the top 100 causes, drug...
Article
This study aimed to describe the clinical and procedural characteristics of drug poisoning, to examine procedural differences between drug poisoning repeaters and non-repeaters, and to estimate the costs of drug poisoning. A retrospective cohort study of a nationally representative sample of 6585 inpatients with drug poisoning was conducted, using...
Article
Full-text available
Although the validity and safety of antipsychotic polypharmacy remains unclear, it is commonplace in the treatment of schizophrenia. This study aimed to investigate the degree that antipsychotic polypharmacy contributed to metabolic syndrome in outpatients with schizophrenia, after adjustment for the effects of lifestyle. A cross-sectional survey w...
Article
Few studies have been conducted on the rationales for using interpretive guidelines for effect size, and most of the previous statistical power surveys have covered broad research domains. The present study aimed to estimate the statistical power and to obtain realistic target effect sizes of depression research in Japan. We systematically reviewed...
Article
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Objective: The aim of this study was to estimate the annual national cost of major depressive disorder among adults 20 years and older in Japan in 2008. Method: The analysis used was a top-down costing approach based on national health statistics. From the societal perspective, the costs examined were direct medical costs, depression-related sui...
Article
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Treatment preferences may contribute to seeking and adhering to professional help for depression. Few studies have considered practical barriers and controlled for individual difference factors. To clarify depression treatment preferences among Japanese undergraduates while considering practical barriers and controlling for individual difference fa...
Article
To consider smoke-free policies for the patients with schizophrenia, the present study examined how smoking behavior is related to hospital readmission among patients with schizophrenia. A retrospective study was conducted in 2007 on 460 discharged patients with schizophrenia who voluntarily admitted in the participating psychiatric hospitals at fi...
Article
Despite an increasing concern that atypical antipsychotics seem to have a stronger diabetogenic risk than conventional antipsychotics, little information is available on the prevalence of diabetes among schizophrenia patients, and prescription patterns for patients with comorbid schizophrenia and diabetes in Japan. To compare the prevalence of diab...
Article
Schizotypal personality may be seen as an indicator predisposition to schizophrenia and psychosis proneness. Schizotypal personality traits behave differently depending on a person's age and sex, but few studies have examined the causal relationship between age-related sex differences and schizotypal personality traits. The aim of the present study...
Article
Background: Among seven atypical antipsychotics approved for the treatment of patients with schizophrenia, olanzapine and quetiapine are contraindicated in patients with diabetes in Japan. Objective: To compare diabetes risk of olanzapine and quetiapine with that of other antipsychotics in patients with schizophrenia in Japan. Method: We performe...
Article
The purpose of this study was to translate the Evidence-Based Practice Attitude Scale (EBPAS; Aarons, 2004), which assesses general attitudes toward the adoption of Evidence-Based Practices (EBPs), and to examine the psychometric properties of the Japanese version of the EBPAS. We translated the EBPAS into Japanese using back-translation technique,...
Article
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Although the debate on whether mental disorders are categorical or dimensional is critical for researchers and practitioners, past findings of taxometric studies of depression have been somewhat contradictory and difficult to reconcile. One reason for the disagreement was that most researchers relied only on selected samples (students, clinical pat...
Article
Many depression studies dichotomize the participants as depressed or nondepressed on the basis of a self-reported depression scale score. However, there is little statistical rationale for such a procedure. The purpose of this study was to clarify whether depression assessed by the Zung Self-rating Depression Scale (SDS) is categorical or dimension...
Article
The purpose of the present article is to review the previous continuity controversy of depression, and the findings of the more recent empirical research using taxometric procedures. Proponents of categorical models assume that depression is discrete entities that represent a qualitative distinction from normal functioning, whereas advocates of dim...
Article
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In order to evaluate methods used for depression research in Japan, we reviewed 974 depression studies published in 18 Japanese journals between 1990 and 2006. Nine methodological and procedural characteristics in depression studies were identified and coded. Results revealed that journals could be classified into three types based on research meth...
Article
Low rate of seeking professional help, and medication non-adherence are major obstacles to treatment effectiveness for depression in clinical practice. The aim of this study was to elucidate service attributes contributing to intention to treat for depression. The survey was carried out among 112 staffs in a town, Miyazaki prefecture. Participants...
Article
Low rate of seeking professional help,and medication non-adherence are major obstacles to provide appropriate and effective treatment for depression. The aim of this study was to elucidate information and service factors contributing to intention to treat for depression. Two surveys were carried out among 289 and 129 college students. Participants...
Article
Despite the availability of efficacious treatments for depression, a large proportion of people are reluctant to seek professional help. Perceived utility and risk of intervention for depression are hypothesized to predict whether individuals seek and adhere to professional help if they were depressed. By means of a vignette describing major depres...
Article
What are the benefits of negative thinking and negative affect? Although previous studies in evolutionary psychology, social psychology, and clinical psychology have clarified the question, there has been no definitive study asking people directly about the perceived benefits. In the present study, 119 Japanese undergraduates were asked how they re...

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