Published papers

Healthcare data is rapidly increasing as healthcare smart devices are developed. However, statistical analysis of healthcare big data is difficult due to heterogeneity in data quality and missing data. For such data, data mining methods such as clustering and dimension reduction may be useful as their preliminary analysis. In this paper, we show two illustrative applications; one is a principal component analysis of body composition data and the other is a latent topic analysis of hourly step-count dataset recorded by physical activity monitors. From those analyses, we proposed independent indices of body size and hidden obesity and extracted some diurnal patterns in ambulatory activities.

© 2020 The Author(s). Background: In the context of worldwide public health, it is very important to promote physical activity among the older people. This study explored the roles and attitudes of senior leaders in promoting group-based exercise in their local communities, specifically to determine the level and extent to which to elderly participation was encouraged. Methods: This study conducted semi-structured face-to-face in-depth interviews and employed a subsequent thematic analysis. Participants included 10 club leaders and five sub-leaders who were working at senior clubs in Fujisawa-city, Kanagawa, Japan, from July to September 2018. Results: Four themes emerged from the interview responses, including "unwavering attitude/conviction in relation to the vision,""leaders must set an example,""a search for balance in delegating responsibilities to members,"and "creating and fostering culture and environment of mutual help."Further, each participant outlined several aims, including "achieving healthy longevity for the entire local community,""having older people promote healthy activities among the older people,"and "creating a pro-health town."Conclusions: Findings indicate that policymakers, public health workers, and healthcare providers should recognize the pivotal roles that senior group leaders play in promoting healthy activities for the older people. These efforts should be strongly considered when developing policies and strategies designed to promote overall healthy longevity from a general community perspective.

© 2020, The Author(s). Background: The aim of this study was to determine the effectiveness of the Smart Life Stay (SLS) program, which is an experience-oriented stayover program, in combination with health tourism and mandatory health guidance on glucose metabolism after 2 years. Methods: The participants of the SLS program (n = 792) were recruited from a database of 23 medical insurers. They underwent a mandatory health examination termed Specific Health Checkups in 2014. The participants were included if they had diabetes or were at a high risk of diabetes and if they satisfied the following inclusion criteria: (1) body mass index (BMI; kg/m2) > 25, or (2) waist circumference (WC; cm) > 85 for men and > 90 for women, or (3) hemoglobin A1c (HbA1c; %) > 5.6, or (4) fasting plasma glucose (FPG; mg/dl) > 100. Individuals who corresponded to one or more items were included as study participants. The control subjects (n = 3645) were nonparticipants of the program who were selected from the database and met the inclusion criteria. The lifestyle changes and changes in mean BMI, WC, FPG, and HbA1c in both groups from baseline to 2-year follow-up were compared by inverse probability weighting of a propensity score. Results: The percentage of people who exercised regularly increased significantly in the SLS group compared with the control group. In the SLS group, BW, BMI, and WC significantly decreased by 1.75 kg, 0.60 kg/m2, and 1.45 cm, respectively, whereas in the control group, WC, FPG, and HbA1c increased significantly by 0.38 cm, 3.37 mg/dl, and 0.12%, respectively. The comparison between groups revealed that the BW, BMI, WC, FPG, and HbA1c improved significantly in the SLS group. Conclusions: The SLS program is suggested to help improve glucose metabolism. This program could be a feasible option as a lifestyle intervention program for diabetes.

Background: On April 7, 2020, Japan declared a state of emergency due to the first wave of coronavirus disease 2019 (COVID-19) with the associated social distancing likely to have had a great impact on older adults’ lifestyle and health. This study aimed to explore the behavioral changes and personal hygiene practices in relation with background psychosocial and health characteristics of older adults during the COVID-19 emergency. Methods: A cross-sectional telephonic survey was conducted with the participants of the Kawasaki Aging and Wellbeing Project (KAWP), an on-going longitudinal cohort study of older adults aged 85 or older. The interviews were conducted using a structured questionnaire consisting of 11 closed questions regarding behavioral changes and personal hygiene practices during the state of emergency. Sociodemographic and health data were obtained from the KAWP baseline survey conducted 2.2 years before the telephonic survey. Results: Overall, 487 participants from the KAWP responded to the telephonic survey (response rate: 89.2%). 94.5% of the respondents reported no changes in basic lifestyle habits, such as eating, sleeping, smoking, and drinking, whereas 28.1% reported a decrease in physical activity, and 54.6% reported going out less frequently. One-third of the respondents reported a decrease in the number of people to converse with, as well as the amount of time to converse. For personal hygiene practices, 93.8% reported wearing a mask when they went out, and 50.3% reported an increased frequency of handwashing. Multiple logistic regression analysis revealed that engagement in physical activity at baseline (odds ratio [OR] = 1.95, 95% confidence interval [CI] = 1.23–3.08), smartphone ownership (OR = 2.15, 95% CI = 1.33–3.47), and visual impairment (OR = 1.79; 95% CI = 1.10–2.91) were independently associated with decreased physical activity during the COVID-19 emergency. Female respondents and smartphone ownership were significantly associated with more frequent handwashing. Conclusions: The study revealed that older adults in an urban setting responded to the COVID-19 emergency with behavioral changes. The findings of this study have implications for the design of preventive strategies to maintain the health and wellbeing of at-risk older adults.

Latent Dirichlet allocation (LDA) is a popular topic model for extracting common patterns from discrete datasets. It is extended to the pachinko allocation model (PAM) with a hierarchical topic structure. This paper presents a combination meal allocation (CMA) model, which is a further enhanced topic model from the PAM that has both hierarchical categories and hierarchical topics. We consider count datasets in multiway arrays, i.e., tensors, and introduce a set of topics to each mode of the tensors. The topics in each mode are interpreted as patterns in the topics and categories in the next mode. Despite there being a vast number of combinations in multilevel categories, our model provides simple and interpretable patterns by sharing the topics in each mode. Latent topics and their membership are estimated using Markov chain Monte Carlo (MCMC) methods. We apply the proposed model to step-count data recorded by activity monitors to extract some common activity patterns exhibited by the users. Our model identifies four daily patterns of ambulatory activities (commuting, daytime, nighttime, and early-bird activities) as sub-topics, and six weekly activity patterns as super-topics. We also investigate how the amount of activity in each pattern dynamically affects body weight changes.

目的:成人を対象に,冬季の暖房使用と住宅内の座位行動および身体活動の関連を検討すること。方法:本研究は横断研究である。調査は沖縄県を除く46都道府県の工務店等を通して募集した断熱改修工事予定のある住宅に居住する20歳以上の成人を対象に2014年度から2017年度までの冬季(11月〜4月)に実施し,3,874名から同意を得た。加速度計は連続14日間の装着を依頼した。行動日誌から覚醒在宅時間帯を特定し,住宅内の座位行動と身体活動を評価した。コタツおよび脱衣所暖房使用の有無と住宅内の座位行動,身体活動との関連は目的変数を対数変換したうえで,日レベル(室温,オフセット項として覚醒在宅時加速度計装着時間等),個人レベル(年齢,BM等),世帯レベル(世帯年収,同居人数等)で調整した線形混合モデル(ランダム切片モデル)を男女別に実施した。非標準化偏回帰係数は指数変換し,目的変数への関連の程度を算出した。結果:有効データは3,482名であった。多変量解析の結果,コタツを使用しない場合は住宅内の座位行動時間が約2%短く[男性:exp(B)=0.98,p=0.022,女性:exp(B)=0.98,p=0.020],その中断回数は約10%多く[男性:exp(B)=1.10,p=0.001,女性:exp(B)=1.11,p<0.001],身体活動も5〜7%多かった[男性:exp(B)=1.07,p=0.005,女性:exp(B)=1.05,p=0.012]。脱衣所を暖房する場合も同様の関連が確認された。結論:コタツを使用しない人,脱衣所を暖房する人は,住宅内の座位行動時間が短く,かつ頻繁に中断し,身体活動量も多かった。局所暖房を使用せず,非居室でも暖房を行い家を暖かく保つことは,住宅内の座位行動を抑制し身体活動を促進する可能性がある。(著者抄録)

The 2020 Yokohama Sport Conference, an international conference in harmony with the 2020 Olympic and Paralympic Games, was initially planned to be held in Yokohama from 8 to 12 September, 2020. However, the COVID-19 pandemic significantly affected the conference; the conference style and dates were changed and many programs were altered or cancelled. All sessions in which Japanese Association of Exercise Epidemiology was involved were also cancelled. Then, owing to the stakeholders' passions, kind understanding and help, we replanned and held online lectures and a talk by Dr. Fiona Bull (Head of Physical Activity Unit, Department of Health Promotion, Division of Healthier Populations, World Health Organization) and Dr. Daichi Suzuki (Commissioner, Japan Sports Agency) on September 9, 2020 as a public program, connecting Switzerland and Japan in real-time. As we could not have enough time for discussions among participants of the public program, we also held an online reflection session on the following day. Here, we summarize the process and contents of these sessions and discuss future perspectives, based on the findings from the sessions as an implementation of dissemination of exercise epidemiology.

Although physical activity has many recognized health benefits, the number of inactive persons is increasing worldwide. At the World Health Assembly in May 2018, a resolution to tackle the widespread problem of physical inactivity was made, and in June of the same year, the World Health Organization announced its Global Action Plan on Physical Activity 2018–2030 (GAPPA). To reduce physical inactivity and create a healthy and sustainable world, GAPPA set out the following four strategic objectives: "create active societies," "create active environments," "create active people," and "create active systems." These objectives are achievable through 20 policy actions, each comprising 4–6 items. These strategic objectives and policy actions do not function independently, but are interrelated and can generate co-benefits for one another through a systems-based approach, achieved through the cooperation of each field. Outcomes relate not only to health but also to many Sustainable Development Goals (SDGs). We share these aims when envisioning a long-term Olympic legacy. In the future, it will be necessary for stakeholders to gather at each level, deeply understand GAPPA objectives, and devise an appropriate system plan for execution, reevaluation, sharing, and scaling-up.

In November 2020, the International Society for Physical Activity and Health (ISPAH) published “Eight Investments That Work for Physical Activity". This document was updated from ISPAH's 2011 publication: ”Non Communicable Disease Prevention: Investments That Work for Physical Activity (2011)” following the “Toronto Charter on Physical Activity: A Global Call for Action” published in 2010. Along with the “WHO Global Action Plan on Physical Activity 2018-2030”, this is useful as guidance for promoting physical activity. This document emphasized that physical activity promotion will not only improve people's health, but also contribute to a better society and the achievement of the Sustainable Development Goals (SDGs) developed by the United Nations. The strategy to promote physical activity is based on a systems-based approach, which recommends measures in eight areas: 1) whole-of-school programmes, 2) active transport, 3) active urban design, 4) healthcare, 5) public education, including mass media, 6) sport and recreation for all, 7) workplaces, and 8) community-wide programmes. This paper outlines the document and introduces its Japanese translation version.

Introduction: Physical activity is known to reduce the risk of cancer morbidity and mortality, and to give the health benefits for cancer survivors. For example, after receiving cancer diagnosis, appropriate physical activity can improve prognosis afterwards. Evidence is available to show the risk of cancer-related mortality falls to 50% in the group that continues exercise after a cancer diagnosis. Previous interventional studies also show improvement in physical fitness, quality of life, mood, reduced anxiety and depression/fatigue, an effect on body image/body composition, and an improvement in biomarkers related to cancer risk and outcome.Current status of physical activities: Based on this evidence, the American Cancer Society/American College of Sports Medicine recommends that cancer survivors engage in 150 minutes per week of moderate-intensity aerobic physical activity (or 75 minutes/week of vigorous-intensity aerobic physical activity) and two strength training sessions per week, as well as decreased sedentary time. However, <30% of persons diagnosed with cancer are reported to meet the recommended levels. To maintain high physical activity in real life settings, a feasible strategy in society should be established.Toward Social Implementation: In the 2017 Clinical Practice Guidelines (Canada), evidence supports the promotion of exercise in a group or supervised settings. For sustainable engagement in physical activity, it is important to be able to exercise under guidance and to promote physical activities in daily life, depending on the situation.