CCChifa Chiang

Chifa Chiang

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Chifa Chiang has a total of 94 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Factors Related to mHealth App Use Among Japanese Workers: Cross-Sectional Survey

    by Itsuko Ozaki, Mariko Nishijima, Eiji Shibata, Yuri Zako, Chifa Chiang

    Background: Health care providers can make health guidance more effective by using mobile health technologies such as health apps. Although health care providers need to know who uses health apps, existing studies have yielded inconsistent results. Objective: The aim of the study was (1) to clarify the prevalence and patterns of health app use to improve health behaviors for preventing lifestyle-related diseases among Japanese workers and (2) to identify the associations among demographic characteristics, health behavior, and internet use and health app use by gender. Methods: Data were collected from a cross-sectional internet survey in 2023. In total, 2200 participants were included, with an even distribution of men and women in each age group aged 20 to 60 years. The participants were workers with smartphones and reported their gender, age, residence area, marital status, education, employment status, occupation, work pattern, diseases under treatment, health checkups, health guidance, health behaviors, internet use duration, and number of devices used. We asked about current and previous health app use for 1 month. A multivariate logistic regression analysis was conducted by gender. Results: Of the participants, 472 (21.5%) and 189 (8.6%) were current and previous health app users, respectively. Most current and previous health app users used features that record and track their physical activity and other health behaviors. Health app users—both men and women—were more likely to have health checkups (odds ratio [OR] 1.53, 95% CI 1.12-2.11 and OR 1.51, 95% CI 1.10-2.07, respectively), receive health guidance (OR 2.01, 95% CI 1.47-2.74 and OR 1.86, 95% CI 1.32-2.62, respectively), engage in regular physical activity (OR 2.57, 95% CI 1.91-3.47 and OR 1.94, 95% CI 1.41-2.67, respectively), use the internet for 120-179 minutes per day (OR 1.76, 95% CI 1.13-2.75 and OR 1.70, 95% CI 1.12-2.57, respectively), and were less likely to be older (50-59 years: OR 0.54, 95% CI 0.33-0.88 and OR 0.40, 95% CI 0.25-0.6, respectively, and 60-69 years: OR 0.37, 95% CI 0.22-0.62 and OR 0.47, 95% CI 0.28-0.77, respectively). According to gender, male health app users were more likely to be married (OR 1.69, 95% CI 1.23-2.33) and less likely to work in the security, agriculture, forestry, fishing, manufacturing, or transportation industries (OR 0.62, 95% CI 0.41-0.95). Female health app users were more likely to have a university education or higher (OR 1.55, 95% CI 1.061-2.26), maintain an appropriate body weight (OR 1.52, 95% CI 1.10-2.11), and use 3 or more devices (OR 2.13, 95% CI 1.41-3.23). Conclusions: Physical activity and health guidance are strong predictors of app use. Health care providers should assess the target populations’ preferences for app use based on their characteristics, support their app use, and enhance the effectiveness of health guidance.


  • Open Access

    Nonrestorative Sleep and Type 2 Diabetes Incidence: The Aichi Workers’ Cohort Study

    by Jingyi Lin, Zean Song, Yuanying Li, Chifa Chiang, Yoshihisa Hirakawa, Yoshihisa Nakano, Young-Jae Hong, Masaaki Matsunaga, Atsuhiko Ota, Koji Tamakoshi, et al.

    Background: The term "nonrestorative sleep (NRS)" refers to unrefreshed feeling at wake-up and is a domain of poor sleep quality. Previous researches have demonstrated that NRS is linked to a number of diseases and adverse health outcomes, but less is known regarding the link between NRS and diabetes, particularly in Japanese.Methods: We studied 3665 middle-aged male participants of the Aichi Workers' Cohort Study who were followed-up from 2002 to 2019. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of incident type 2 diabetes mellitus (T2DM) in relation to NRS adjusted for potential confounding variables.Results: During a median follow-up of 14.6 years, 421 type 2 diabetes cases were identified. Participants with NRS had a higher crude incidence rate of T2DM (11.2/1,000 person-years), compared to participants without NRS (9.3/1,000 person-years). In the fully adjusted model, individuals who reported having NRS had a significantly higher risk of developing T2DM (HR: 1.36, 95% CI: 1.10-1.67). The association was observed only in participants under 50 years old (HR: 1.82, 95% CI: 1.36-2.43), not in the older (50 years or older) participants (P for interaction =0.025). In contrast, stratified analyses by the presence of shift work, obesity or sleep duration showed similar associations in all the strata.Conclusions: NRS was associated with higher risk of T2DM in middle-aged Japanese male workers independent of a variety of lifestyle factors and other sleep problems.


  • Open Access

    Factors Related to mHealth App Use Among Japanese Workers: Cross-Sectional Survey (Preprint)

    by Itsuko Ozaki, Mariko Nishijima, Eiji Shibata, Yuri Zako, Chifa Chiang

    BACKGROUND Health care providers can make health guidance more effective by using mobile health technologies such as health apps. Although health care providers need to know who uses health apps, existing studies have yielded inconsistent results. OBJECTIVE The aim of the study was (1) to clarify the prevalence and patterns of health app use to improve health behaviors for preventing lifestyle-related diseases among Japanese workers and (2) to identify the associations among demographic characteristics, health behavior, and internet use and health app use by gender. METHODS Data were collected from a cross-sectional internet survey in 2023. In total, 2200 participants were included, with an even distribution of men and women in each age group aged 20 to 60 years. The participants were workers with smartphones and reported their gender, age, residence area, marital status, education, employment status, occupation, work pattern, diseases under treatment, health checkups, health guidance, health behaviors, internet use duration, and number of devices used. We asked about current and previous health app use for 1 month. A multivariate logistic regression analysis was conducted by gender. RESULTS Of the participants, 472 (21.5%) and 189 (8.6%) were current and previous health app users, respectively. Most current and previous health app users used features that record and track their physical activity and other health behaviors. Health app users—both men and women—were more likely to have health checkups (odds ratio [OR] 1.53, 95% CI 1.12-2.11 and OR 1.51, 95% CI 1.10-2.07, respectively), receive health guidance (OR 2.01, 95% CI 1.47-2.74 and OR 1.86, 95% CI 1.32-2.62, respectively), engage in regular physical activity (OR 2.57, 95% CI 1.91-3.47 and OR 1.94, 95% CI 1.41-2.67, respectively), use the internet for 120-179 minutes per day (OR 1.76, 95% CI 1.13-2.75 and OR 1.70, 95% CI 1.12-2.57, respectively), and were less likely to be older (50-59 years: OR 0.54, 95% CI 0.33-0.88 and OR 0.40, 95% CI 0.25-0.6, respectively, and 60-69 years: OR 0.37, 95% CI 0.22-0.62 and OR 0.47, 95% CI 0.28-0.77, respectively). According to gender, male health app users were more likely to be married (OR 1.69, 95% CI 1.23-2.33) and less likely to work in the security, agriculture, forestry, fishing, manufacturing, or transportation industries (OR 0.62, 95% CI 0.41-0.95). Female health app users were more likely to have a university education or higher (OR 1.55, 95% CI 1.061-2.26), maintain an appropriate body weight (OR 1.52, 95% CI 1.10-2.11), and use 3 or more devices (OR 2.13, 95% CI 1.41-3.23). CONCLUSIONS Physical activity and health guidance are strong predictors of app use. Health care providers should assess the target populations’ preferences for app use based on their characteristics, support their app use, and enhance the effectiveness of health guidance. CLINICALTRIAL

  • Open Access

    Applicability of a Web-based 24-hour Dietary Recall Tool for Japanese Populations in Large-scale Epidemiological Studies

    by Yoshie Hose, Junko Ishihara, Ayaka Kotemori, Misako Nakadate, Sachiko Maruya, Junta Tanaka, Hiroshi Yatsuya, Atsuko Aoyama, Chifa Chiang, Tsuneo Konta, et al.

    Background: Recent innovations in information and communication technology have made it possible to assess diet using web-based methods; however, their applicability in the general population remains unclear. Hence, we aimed to examine the applicability of a web-based 24-hour dietary recall (24HR) tool to large-scale epidemiological studies by determining the sampling rate and characteristics of randomly selected participants from a Japanese cohort study.Methods: In total, 5,013 individuals were recruited from a cohort of 21,537 individuals, and 975 agreed to participate in this study. The participants selected either self-administered web-based dietary 24HR (self-administered 24HR) or interviewer-administered telephone-based 24HR (interviewer-administered 24HR) as the method for the dietary assessment and answered questions regarding the acceptability of the system.Results: The response rate of the 975 participants was 19.4%, corresponding to approximately 4.5% of the total study sample. About half of them chose the self-administered 24HR (46.9%). The median time required for the self-administered and interviewer-administered 24HR was 25 and 27 minutes, respectively. In the self-administered 24HR, older people, regardless of sex, tended to require a longer time, and approximately 60% of the participants rated the ease of use of the system as “somewhat difficult” or “difficult.”Conclusion: Characteristics of the participants in this study were not systemically different from those of the entire study sample. Improvements in the approach to entering cooking details and the dish name selection may be necessary for better acceptability in order to be accepted as a self-administered dietary recall tool.


  • Open Access

    Work and Family Conflicts, Depression, and “Ikigai”: A Mediation Analysis in a Cross-cultural Study Between Japanese and Egyptian Civil Workers

    by Ehab S. Eshak, Sachiko Baba, Hiroshi Yatsuya, Hiroyasu Iso, Yoshihisa Hirakawa, Eman M. Mahfouz, Chiang Chifa, Ryoto Sakaniwa, Ayman S. El-Khateeb

    Background: Work-family conflicts (total-WFCs) could associate with mental health, and having ikigai (a purpose of life) may mediate this association.Methods: In a cross-cultural study of 4792 Japanese Aichi Workers’ Cohort study participants and 3109 Egyptian civil workers, the Midlife Development in the United States (MIDUS) questionnaire measured total-WFCs and Center for Epidemiological Studies Depression (CES-D) 11-item scale measured depression. Logistic regression models estimated odds ratios (ORs) of having depression and a high-ikigai across levels of total-WFCs (low, moderate, and high), and the PROCESS macro of Hayes tested the mediation effect.Results: The prevalence of high total-WFCs, depression, and having a high-ikigai were 17.9%, 39.4%, and 70.1% in Japanese women, 10.5%, 26.8%, and 70.1% in Japanese men, 23.7%, 58.2%, and 24.7% in Egyptian women, and 19.1%, 38.9%, and 36.9% in Egyptian men. Compared with participants with low total-WFCs, the multivariable ORs (95% CIs) of depression in Japanese women and men with high total-WFCs were 4.11 (2.99-5.65) and 5.42 (4.18-7.02), and those in Egyptian women and men were 4.43 (3.30-5.95) and 4.79 (3.53-6.48). The respective ORs of having a high-ikigai were 0.46 (0.33-0.64) and 0.40 (0.31-0.52) in Japanese women and men and were 0.34 (0.24-0.48) and 0.28 (0.20-0.39) in Egyptian women and men. No interaction between total-WFCs and country was observed for the associations with depression or ikigai. Ikigai has mediated (up to 18%) the associations between the total-WFCs and depression, especially in Egyptian civil workers.Conclusions: Total-WFCs were associated with depression, and having low-ikigai mediated these associations in Japanese and Egyptian civil workers.


  • Open Access

    Relationship Between Fasting Blood Glucose Levels in Middle Age and Cognitive Function in Later Life: The Aichi Workers’ Cohort Study

    by Masako Shimoda, Kayo Kaneko, Takeshi Nakagawa, Naoko Kawano, Rei Otsuka, Atsuhiko Ota, Hisao Naito, Masaaki Matsunaga, Naohiro Ichino, Hiroya Yamada, et al.

    Background: There is limited evidence regarding the relationship between Diabetes mellitus (DM) in middle age and mild cognitive impairment after a follow-up. Therefore, we investigated the relationship between fasting blood glucose (FBG) levels in middle age and cognitive function (assessed using the Japanese version of the Montreal Cognitive Assessment (MoCA-J) in later life, following over 15 years of follow-up in the Aichi Workers’ Cohort Study in Japan.Methods: Participants were 253 former local government employees aged 60–79 years in 2018 who participated in a baseline survey conducted in 2002. Using baseline FBG levels and self-reported history, participants were classified into the normal, impaired fasting glucose (IFG) and, and DM groups. Total MoCA-J score ranges from 0 to 30, and cognitive impairment was defined as MoCA-J score ≤25 in this study. A general linear model was used to estimate the mean MoCA-J scores in the FBG groups, adjusted for age, sex, educational year, smoking status, alcohol consumption, physical activity, body mass index, systolic blood pressure, total cholesterol, and estimated glomerular filtration rate.Results: The mean MoCA-J score in the total population was 25.0, and the prevalence of MoCA-J score ≤25 was 49.0%. Multivariable-adjusted total MoCA-J scores were 25.2, 24.8, and 23.4 in the normal, IFG, and DM groups, respectively. The odds ratio of MoCA-J score ≤25 in the DM group was 3.29.Conclusions: FBG level in middle age was negatively associated with total MoCA-J scores assessed later in life, independent of confounding variables.


  • Open Access

    Possible contribution of COVID-19 vaccination to the subsequent mental well-being in Japan

    by Chifa Chiang, Shuhei Morita, Yoshihisa Hirakawa, Farzana Tanzin Priya, Yuka Matsumoto, Atsuhiko Ota, Hiroshi Yatsuya, Takahiro Tabuchi

    The coronavirus disease 2019 (COVID-19) pandemic has had a severe impact on mental well-being. Vaccination may have played a pivotal role in enduring this mental health crisis. The present study aimed to longitudinally investigate the association between COVID-19 vaccination and mental health status among Japanese population in 2021. Longitudinal data of 17,089 individuals aged 15–79 years who participated in a nationwide online study were analyzed. Baseline and follow-up mental health statuses were assessed using the Kessler Psychological Distress Scale (K6). General linear and multivariable logistic regression models adjusted for baseline levels of mental distress were used to examine the association between vaccine receipt and follow-up levels of mental health. Mean K6 scores were lower in the vaccinated than in the non-vaccinated participants. Those who had received one or two doses of COVID-19 vaccines were associated with improved mental health at follow-up in subjects with psychological distress at baseline (odds ratio [OR] 1.31 and 1.35, respectively) and were inversely associated with deteriorated mental health status at follow-up in subjects without psychological distress at baseline (OR 0.66 and 0.70, respectively) compared with no vaccination groups, respectively. The present study would indicate that one or two doses of COVID-19 vaccinations contributed to mental well-being in Japan. This finding might provide evidence for promoting vaccination against COVID-19 and emerging infectious diseases in the future.


  • Open Access

    Age and sex differences in factors associated with hypertension among an urban poor population in Bangladesh

    by Abubakr Ahmed Abdullah Al-Shoaibi, Chifa Chiang, Md Khalequzzaman, Sohel Reza Choudhury, Yoshihisa Hirakawa, Syed Shariful Islam, Atsuko Aoyama, Hiroshi Yatsuya

    This study explores the differences in factors associated with hypertension between younger and older subjects in an urban slum community in Bangladesh. We analyzed the data of 1,008 men and 1,001 women obtained from a cross-sectional survey conducted between October 2015 and April 2016. Multivariable logistic regression models were stratified by age (18 to 44 and 45 to 64 years) in men and women separately. The multivariable model included age (continuous) and the following categorical variables simultaneously: education duration, marital status, tobacco smoking, smokeless tobacco use, total physical activity, body mass index (BMI), waist circumference, and the blood levels of glycated hemoglobin (HbA1c), triglycerides, high- and low-density lipoprotein (HDL and LDL) cholesterol. Hypertension was defined as the presence of either blood pressure >= 140/90 mmHg or the use of antihypertensive medication. The prevalence of hypertension was 13.0% (younger men), 14.6% (younger women), 35.6% (older men), and 38.7% (older women). In younger men, higher waist circumference and increased LDL cholesterol levels were significantly associated with hypertension. In older men, physical activity was the only significant factor that was inversely associated with hypertension. In younger women, higher BMI, increased HbA1c, triglycerides, and LDL cholesterol levels were associated with hypertension. In older women, a higher HbA1c was the only factor significantly associated with hypertension. These findings suggest that public health interventions to prevent hypertension may require different approaches according to sex and age groups within the poor urban population in Bangladesh.


  • Open Access

    Dietary salt intake and its correlates among adults in a slum area in Dhaka, Bangladesh: a cross-sectional study

    by Fahmida Afroz Khan, Md Khalequzzaman, Md Hasan, Sohel Reza Choudhury, Chifa Chiang, Atsuko Aoyama, Syed Shariful Islam

    High dietary salt intake increases the risk of noncommunicable diseases (NCDs). NCDs are increasing among the urban poor in Bangladesh, but the data of their dietary salt intake are yet scarce. This study aimed to explore the amount of dietary salt intake among adults in an urban slum area in Dhaka, Bangladesh. A cross-sectional community-based study was conducted. We randomly selected 100 residents (39 men and 61 women) aged 20-59 years without history of NCDs. A modified World Health Organization standard instrument was used for behavioral risk factor assessment and physical measurements. Dietary salt intake was estimated from the measurement of sodium (Na) excretion in spot urine samples.The estimated mean dietary salt intake was 7.8 +/- 2.5 g/day, and the mean Na/potassium (K) ratio in urine was 4.9 +/- 3.4. More than half (54%) of them always took additional salt in their meals, but only 6% of them consumed 5 or more servings of fruits and vegetables per day. A quarter of them perceived salt reduction not at all important. Increased mean salt intakes were marginally associated with lower waist circumference and lower waist-hip ratio. Dietary salt intake among urban slum residents was higher than the recommended level of 5 g/day; however, its association with NCD risk factors was not significant. Further studies are required to identify the urban poor specific factors.


  • Perceptions and behaviors related to noncommunicable diseases in Palau: a qualitative study

    by Hiroko Shimizu, Yoshihisa Hirakawa, Chifa Chiang, Bernie Ngiralmau, Julita Tellei, Faustina K Rehuher-Marugg, Takashi Mita, Hiroshi Yatsuya, Atsuko Aoyama

    The increasing burden of noncommunicable diseases (NCDs) is a major public health concern in Palau. This study aims to identify social and psychological factors related to NCDs among Palauan people using a qualitative approach. We conducted eight key informant interviews and eight focus group discussions, which were audio-recorded, transcribed and translated into English. Ideas of the respondents were extracted and labeled, and the labels were analyzed using an inductive multistage approach referred to as qualitative content analysis. Three themes emerged: (1) home education, (2) traditional local community, and (3) modernization and westernization of lifestyle. Respondents believed that the influence of the family on lifestyle was significant, but that disciplining children at home had become difficult. They considered that the traditional lifestyle was mostly healthy, and were reluctant to abandon certain unhealthy customs, such as serving abundant food to guests as a sign of fraternity. They also thought that they overate because of their stressful modernized lifestyle. This is the first qualitative study to analyze perception and behavior of the Palauan people in relation to NCDs. We found that the increase in NCDs was related to two concurrent trends: preserving certain traditional customs unfavorable to good health, and abandoning time-consuming healthy traditional lifestyle to adopt a modernized one. We also found that Palauan people were not confident in their ability to prevent NCDs. Therefore, health promotion activities should be designed to empower people to make positive changes.