医学部 乳腺外科

Yuito Hosaka

  (保坂 唯仁)

Profile Information

Affiliation
Fujita Health University

J-GLOBAL ID
202201020817428608
researchmap Member ID
R000033736

Papers

 29
  • Yuchi Maeda, Masaaki Matsunaga, Yuito Hosaka, Koji Ishikawa, Atsuhiko Ota
    Journal of occupational health, Apr 9, 2026  
    OBJECTIVES: While the health issues of expatriates have predominantly been investigated in the context of assignments to developing countries, there is a paucity of research addressing Japanese expatriates stationed in the United States, which is a developed country. METHODS: This study employed quantitative content analysis, using the text mining software "KH Coder 3," on records obtained from 17 Japanese expatriates who participated in interviews with an occupational physician during a United States medical tour in May 2025. RESULTS: The interview records comprised 7856 words and 440 sentences. Co-occurrence network analysis extracted six factors: The following subjects were examined: "Family Life and Daily Challenges," "Extended Working Hours and Meetings Between Japan and the United States," "Comprehensive Health Checkups (Ningen Dock) and Patterns of Health Care Utilization," "Health Checkups and Test Results," "Workload and Stress," and " Physical Inactivity and Weight Gain." Among these, the factor with the highest frequency of constituent terms was "Extended Working Hours and Meetings Between Japan and the United States." CONCLUSIONS: Japanese expatriates encounter considerable health challenges, including difficulties in daily life, limited access to medical care, insufficient physical activity, and the substantial burden of work and meetings that extend late into the night owing to time differences. Global companies should ensure appropriate management of health- and work-related issues, even in assignments to developed countries, with particular attention to support systems, such as adjusting meeting schedules and providing family support.
  • 服部 優奈, 高田 碧, 宋 澤安, 福田 知里, 西尾 七海, 近藤 寛, 保坂 唯仁, 松永 眞章, 太田 充彦, 玉腰 浩司, 大塚 礼, 八谷 寛
    東海公衆衛生雑誌, 13(2) 150-160, Mar, 2026  
  • Zean Song, Midori Takada, Shuang Wang, Nanami Nishio, Xuliang Shi, Mei Kobayashi, Masaaki Matsunaga, Yuito Hosaka, Atsuhiko Ota, Rei Otsuka, Koji Tamakoshi, Hiroshi Yatsuya
    Journal of occupational health, Jan 29, 2026  
    BACKGROUND: Work-related stress is associated with cardiovascular disease (CVD), yet the contributions of specific work-related stressors, support and satisfaction to CVD incidence are not fully understood. Clarifying whether lifestyle behaviors and physiological factors mediate associations between stressors and CVD is essential for targeted prevention. METHODS: In this prospective cohort study, a cohort of 4,820 Japanese workers (3,876 men and 944 women) aged 35-65 years was followed up for CVD incidence from 2007 to 2022. Work-related stressors (e.g., quantitative job overload), support (e.g., supervisor support) and satisfaction (e.g., family life satisfaction) were assessed using the 57-item Brief Job Stress Questionnaire. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD risk. Mediation analysis evaluated the role of lifestyle behaviors (e.g., smoking, alcohol consumption) and physiological factors (e.g., systolic blood pressure, obesity) in the association between stressors and CVD incidence. RESULTS: Quantitative job overload, low supervisor support, and low family life satisfaction were independently associated with increased CVD incidence (HRs ranging from 1.69 to 2.33). A part (24.9%) of the association of quantitative job overload with CVD was significantly mediated by obesity (p=0.007). CONCLUSION: Quantitative job overload, lack of supervisor support, and low family life satisfaction were significant predictors of CVD among Japanese civil servants. These findings suggest that both reducing excessive workload and strengthening support systems inside and outside the workplace may be important for cardiovascular disease prevention among Japanese civil servants.
  • Masaaki Matsunaga, Yupeng He, Zean Song, Midori Takada, Hiroshi Yatsuya, Atsuhiko Ota
    Journal of cancer survivorship : research and practice, Jan 27, 2026  
    PURPOSE: This study aimed to (1) identify distinct multidimensional fatigue profiles among employed cancer survivors, (2) examine associations between workplace factors and these profiles, and (3) assess how these profiles are associated with occupational outcomes. METHODS: Seventy-two employed cancer survivors aged 27 to 64 years (median 9.4 years since diagnosis) from a local government in Japan completed questionnaires in 2023 assessing cancer-related fatigue (Cancer Fatigue Scale), workplace factors (job demands, job control, workplace support), and occupational outcomes (work engagement, presenteeism, cognitive function at work, and quality of life). Fatigue profiles were identified using hierarchical cluster analysis. Associations between workplace factors and profiles were examined using multinomial logistic regression. Occupational outcome differences among profiles were examined using linear regression. RESULTS: Three profiles were identified: Low Global Fatigue (n = 12), Dominant Mental Fatigue (n = 36), and High Global Fatigue (n = 24). Workplace support-particularly supervisor understanding, colleague understanding, and schedule flexibility-was associated with approximately 75% lower odds of belonging to the High Global Fatigue group. Job demands and job control showed no associations. The High Global Fatigue group reported lower work engagement, higher presenteeism, reduced cognitive function at work, and poorer quality of life compared to the other groups. CONCLUSIONS: Three multidimensional fatigue profiles were identified among employed cancer survivors. Workplace support factors were more strongly associated with fatigue profiles than job characteristics. These profiles were associated with occupational outcomes. IMPLICATION FOR CANCER SURVIVORS: These distinct fatigue profiles can guide personalized workplace interventions to optimize support for employed cancer survivors.
  • Zean Song, Midori Takada, Young-Jae Hong, Baruck Tegegn Endale, Nanami Nishio, Misuzu Horikoshi, May Thet Khine, Masaaki Matsunaga, Yupeng He, Atsuhiko Ota, Rei Otsuka, Koji Tamakoshi, Hiroshi Yatsuya
    International Archives of Occupational and Environmental Health, 99(1), Dec 24, 2025  

Misc.

 10

Professional Memberships

 1

Research Projects

 2
  • Grants-in-Aid for Scientific Research, Japan Society for the Promotion of Science, Oct, 2013 - Mar, 2018
    Aoyama Atsuko, Sherilynn Madraisau, Edolem Ikerdeu, Bernie Ngiralmau, Berry Moon Watson, Singeru Travis Singeo, Jr, Gregorio Ngirmang, Faustina Rehuher Marugg, Julita Tellei, Patrick Tellei, Md. Khalequzzaman, Sohel Reza Choudhury, Bilqis Amin Hoque, Fariha Haseen, Syed Shariful Islam, Mohammad Abdullah Al-Mamun, Shahrin Emdad Rayna, Fahmida Afroz Khan, UEMURA Mayu, WANG Chaochen, OSAKO Ayaka, Abubakr Ahmed Abdullah Al-Shoaibi, ZHANG Yan, Lemlem Weldegerima Gebremariam, HE Yupeng, CUI Renzhe, SATA Mizuki, CUI Meishan, OUCHI Shino
  • Grants-in-Aid for Scientific Research, Japan Society for the Promotion of Science, Apr, 2014 - Mar, 2018
    Yatsuya Hiroshi, HANIBUCHI Tomoya, TOYOSHIMA Hideaki, KOH Keihatsu, YAMASHITA Kentaro, WANG Chaochen, ZHANG Yan, KANEKO Kayo, AL-SHOAIBI Abubakr Ahmed Abdullah, GEBREMARIAM Lemlem Weldegerima, HE Yupeng, SUZUKI Koji, SAYEED Shurovi, KATOH Yoshiji, FUJISAWA Akiko, MATSUNAGA Masaaki, KHINE May Thet