INTRODUCTION: Preterm birth (PTB) remains a leading cause of perinatal morbidity and mortality worldwide. Understanding Singapore's PTB trends and associated risk factors can inform effective strategies for screening and intervention. This study analyses PTB trends in Singapore from 2017 to 2023, identifies risk factors in this multi-ethnic population and evaluates a predictive model for PTB. METHOD: A retrospective analysis of all PTBs between 22+0 and 36+6 weeks of gestation, from 1 January 2017 to 31 December 2023, was performed by extracting maternal and neonatal data from electronic medical records. These PTBs were taken from the registry of births for Singapore and SingHealth cluster data. Cochran- Armitage trend test and multinomial logistic regression were used. An extreme gradient boosting (XGBoost) model was developed to test and predict the risk of PTB. RESULTS: The PTB rate in Singapore did not show a significant change. However, there was modest downward trend in the SingHealth population from 11.3% to 10.2%, mainly in late spontaneous PTBs (sPTBs). sPTBs accounted for ∼60% of PTBs. Risk factors for very/extreme sPTB included Chinese ethnicity, age ≥35 years, body mass index (BMI) ≥23 kg/m², being unmarried, primiparity, twin pregnancy and maternal blood group AB. The XGBoost model achieved an area under the receiver operating characteristic curve of 0.75, indicating moderate ability to predict PTB. CONCLUSION The overall PTB rate in Singapore has not improved. This study underscores the importance of local factors, particularly advanced maternal age, BMI, primiparity, unmarried, Chinese ethnicity and maternal blood group AB influencing PTB risk. Artificial intelligence methods show promise in improving PTB risk stratification, ultimately supporting personalised care and intervention.
Humans ; Singapore/epidemiology* ; Retrospective Studies ; Female ; Risk Factors ; Premature Birth/ethnology* ; Pregnancy ; Adult ; Infant, Newborn ; Asian People/statistics & numerical data* ; Gestational Age ; Body Mass Index ; Maternal Age ; Logistic Models ; Ethnicity

BACKGROUND: Epidemiological data on chronic diarrhea in the Chinese population are lacking, and the association between obesity and chronic diarrhea in East Asian populations remains inconclusive. This study aimed to investigate the prevalence of chronic diarrhea and its association with obesity in a representative community-dwelling Chinese population. METHODS: This cross-sectional study was based on a multistage, randomized cluster sampling involving 3503 residents aged 20-69 years from representative urban and rural communities in Beijing. Chronic diarrhea was assessed using the Bristol Stool Form Scale (BSFS), and obesity was determined based on body mass index (BMI). Logistic regression analysis and restricted cubic splines were used to evaluate the relationship between obesity and chronic diarrhea. RESULTS: The standardized prevalence of chronic diarrhea in the study population was 12.88%. The average BMI was 24.67 kg/m 2 . Of all the participants, 35.17% (1232/3503) of participants were classified as overweight and 16.13% (565/3503) as obese. After adjustment for potential confounders, individuals with obesity had an increased risk of chronic diarrhea as compared to normal weight individuals (odds ratio = 1.58, 95% confidence interval: 1.20-2.06). A nonlinear association between BMI and the risk of chronic diarrhea was observed in community residents of males and the overall participant group ( P  = 0.026 and 0.017, respectively). CONCLUSIONS This study presents initial findings on the prevalence of chronic diarrhea among residents of Chinese communities while offering substantiated evidence regarding the significant association between obesity and chronic diarrhea. These findings offer a novel perspective on gastrointestinal health management.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Young Adult ; Body Mass Index ; China/epidemiology* ; Chronic Disease/epidemiology* ; Cross-Sectional Studies ; Diarrhea/epidemiology* ; Obesity/complications* ; Prevalence ; East Asian People/statistics & numerical data*

BACKGROUND: Deterioration in lifestyle associated with poor mental health could be an important concern during the coronavirus disease 2019 (COVID-19) pandemic. However, few studies have investigated the association between mental health status and lifestyle changes during the pandemic in nationwide Japanese general population. METHODS: This cross-sectional study was conducted using the data among 1,546 participants of the follow-up study of NIPPON DATA2010 in 2021. Recent mental status, as assessed using the Kessler 6 (K6) scale, and lifestyle changes compared to before the pandemic were determined using self-reported questionnaires. Some lifestyle changes such as decreased physical activity were defined as undesirable, whereas others such as decreased alcohol drinking were defined as desirable. The participants were divided into three groups based on the K6 scores: the K6<5, 5≤K6<9, and K6≥9 groups. The odds ratios (ORs) and 95% confidence intervals (CIs) of the K6 groups for each lifestyle change compared with that in the K6<5 group were estimated after adjusting for possible confounders. RESULTS: The ORs of the K6≥9 group for all undesirable lifestyle changes were significantly high, especially increased alcohol drinking (OR 4.64; 95% CI, 2.71-7.93), and decreased physical activity (OR 4.63; 95% CI, 3.29-6.52). Among the desirable changes, the OR of the 5≤K6<9 group was significantly high for increased eating home cooking. CONCLUSIONS Poor mental health showed a significant association with undesirable lifestyle changes, especially increased alcohol drinking and decreased physical activity, in a nationwide general Japanese population during the COVID-19 pandemic.
Humans ; COVID-19/epidemiology* ; Japan/epidemiology* ; Male ; Female ; Mental Health/statistics & numerical data* ; Middle Aged ; Cross-Sectional Studies ; Life Style ; Adult ; Aged ; Exercise ; Alcohol Drinking/epidemiology* ; SARS-CoV-2 ; Pandemics ; East Asian People

BACKGROUND: Although the global COVID-19 mortality rate is decreasing, COVID-19 remains an infectious disease with a high mortality rate, especially in older adults and individuals with comorbidities. In Japan, mask-wearing has been left to individual discretion since March 13, 2023, but remains a key protective measure. This study aimed to identify factors influencing individual mask-wearing behavior in post COVID-19 era, with a focus on risk factors for severe COVID-19. METHODS: Data from 33,000 participants, obtained from the Japan COVID-19 and Society Internet Survey 2023, were used, which was conducted from September 25 to November 17, 2023. Participants were randomly selected from approximately 2.2 million panelists from a nationwide Japanese Internet research company, with sampling adjusted by age, sex, and living area to match the population distribution in Japan. The association between wearing a mask and risk factors for severe COVID-19 (age, sex, smoking, COVID-19 vaccination, history of COVID-19, body mass index (BMI), and comorbid conditions) was evaluated using univariate and multivariate analyses. RESULTS: In total, 28,481 individuals were included, of whom 18,371 (64.5%) answered that they wore masks. After adjusting for confounders, older age (adjusted relative risk [RR], 1.50; 95% confidence interval [CI], 1.45-1.55 for "75-83" years), no history of COVID-19 (adjusted RR, 1.06; 95% CI, 1.04-1.08), low BMI (adjusted RR, 1.04; 95% CI, 1.02-1.07), and increased number of comorbid conditions (adjusted RR, 1.11; 95% CI, 1.05-1.18 for three or more) were significant positive factors for wearing a mask. In contrast, men (adjusted RR, 0.89; 95% CI, 0.87-0.90), no COVID-19 vaccination (adjusted RR, 0.78; 95% CI, 0.76-0.81), and current smoking history (adjusted RR, 0.96; 95% CI, 0.93-0.99) were significant negative factors. CONCLUSION We demonstrated that mask-wearing behavior differed based on individual risk factors for severe COVID-19, with some risk factors negatively influencing mask use in Japan. It may be necessary to recommend mask-wearing for these individuals, especially during situations such as COVID-19 epidemic season or the onset of epidemics, considering individual mask-wearing behavior.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Male ; Middle Aged ; Young Adult ; COVID-19/psychology* ; Japan/epidemiology* ; Masks/statistics & numerical data* ; Risk Factors ; Surveys and Questionnaires ; East Asian People

BACKGROUND AND AIM: The association between physical activity (PA) and sarcopenia has mostly been investigated in older people, with few studies focused on earlier life stages. The present study aimed to determine whether higher PA levels are associated with a lower sarcopenia risk in middle-aged and early older people. METHODS: This was an 8-year follow-up study. Participants were 6,500 community-dwelling adults aged 40-74 years who participated in the baseline questionnaire survey conducted in 2011-2014 in Japan. Levels of total and leisure-time PAs at baseline were assessed using validated metabolic equivalent scores. Multi-frequency bioelectrical impedance analysis and handgrip strength measurement were performed in 2021-2022, and participants with low height-adjusted appendicular lean mass (<20th percentile) and low grip strength were diagnosed as having sarcopenia (outcome). Covariates were demographics, body size, lifestyle, and disease history at baseline. RESULTS: The prevalence of sarcopenia was 137/2926 (4.7%) for men and 127/3574 (3.6%) for women. Higher total PA levels were associated with lower odds of sarcopenia (P for trend = 0.0278), with the second highest group having a significantly lower OR (0.51) than the lowest group (reference) in women, but not in men. Regarding leisure-time PA, those engaged in leisure-time vigorous PA had a lower OR of sarcopenia than those who did not (OR = 0.67, P = 0.0625). CONCLUSION Higher levels of total PA are associated with a lower risk of sarcopenia in women but not in men, suggesting a sex difference in this association. In addition, high levels of vigorous leisure-time PA may be effective for preventing sarcopenia.
Humans ; Sarcopenia/epidemiology* ; Japan/epidemiology* ; Male ; Female ; Middle Aged ; Aged ; Follow-Up Studies ; Independent Living/statistics & numerical data* ; Exercise ; Adult ; Prevalence ; Risk Factors ; Hand Strength ; East Asian People

BACKGROUND: Pneumonia is a major global public health concern. Taking antioxidant nutrients has attracted attention for their potential role in reducing pneumonia mortality. Although studies in Western countries have evaluated this association, the current evidence remains controversial, and research in Asia remains limited. This cohort study investigated the association between dietary antioxidant nutrients intake and pneumonia mortality in Japanese population. METHODS: Data were collected from the Japan Public Health Center-based Prospective Study between 1995 and 1998, with follow-up until the end of 2018. The intake of antioxidant nutrients was assessed using a validated food-frequency questionnaire. The Cox proportional hazard model was employed to calculate hazard ratios (HRs) and p-trends for pneumonia mortality, adjusting for potential confounding factors including age, area, body mass index, smoking status, alcohol intake, physical activity, postmenopausal status, occupation, coffee intake, green tea intake, antihypertensive medication use, vitamin-supplement use, and total energy intake. RESULTS: The analysis included data from 39,850 men and 46,705 women. Over a median follow-up of 20.8 years, 813 men and 477 women died from pneumonia. The multivariable model revealed that a higher intake of cryptoxanthin (p-trend = 0.027 in men; 0.019 in women), lycopene (p-trend = 0.016 in women), vitamin C (p-trend = 0.022 in men), and vitamin E (p-trend = 0.031 in women) was significantly associated with a reduction in pneumonia mortality. CONCLUSIONS Higher dietary intake of cryptonxanthin, lycopene, and vitamins C and E was associated with a low risk of pneumonia mortality in Japanese adults.
Humans ; Male ; Japan/epidemiology* ; Female ; Prospective Studies ; Middle Aged ; Pneumonia/mortality* ; Antioxidants/administration & dosage* ; Diet/statistics & numerical data* ; Aged ; Adult ; Nutrients ; East Asian People

BACKGROUND: Meals are provided at nursery schools for Japanese preschool children, and this may result in different energy and nutrient intakes on weekdays and weekends. The purpose of this study was to obtain basic information for public nutrition policies in early childhood by examining differences in energy and nutrient intakes of preschool children between weekdays and weekends using meal categories such as breakfast, lunch, dinner, and snacks. METHODS: Energy and nutrient intakes were examined in 761 Japanese preschool children (423 boys, 338 girls) aged 3-6 years attending childcare facilities in seven regions in Japan. Data collection was based on non-consecutive four-day dietary records (two weekdays, two weekend days) in 2019 or 2020. Energy and nutrient intake by meal category were compared using a generalized linear mixed model adjusted for demographic factors. RESULTS: Total energy intake was significantly higher on weekdays for boys (1,478 vs. 1,415 kcal) and girls (1,349 vs. 1,296 kcal) (both P < 0.001). Weekday lunches had higher protein content and essential micronutrients such as potassium, iron, vitamins, and lower fat, saturated fatty acids, and salt, compared to weekend lunches. Similarly, weekday snacks also had significantly higher nutritional consumption for most nutrients compared to weekend equivalents. CONCLUSION These findings suggest that meals at nursery schools, particularly lunch and snacks, result in more desirable nutrient intake in preschool children. On weekdays, children consume meals with higher nutrient density, possibly due to the role of dietitians in menu planning. However, some children still fail to meet the Dietary Reference Intakes for Japanese, indicating a need for improvements in nursery school and home meals. More communication is needed between nursery schools and families, including sharing menus and recipes is essential. The results of this study are of value for development of public health nutrition strategies targeting early childhood.
Humans ; Child, Preschool ; Male ; Japan ; Female ; Energy Intake ; Meals ; Child ; Nutrients/analysis* ; Diet/statistics & numerical data* ; East Asian People

BACKGROUND: Supporting the mental health of researchers is essential to maintaining human resources and advancing science. This study investigated the association between Japanese medical researchers' perceptions of research evaluation processes and their psychological well-being. METHODS: We performed a web-based self-administered questionnaire survey. The questionnaires were distributed to each academic society through the Japanese Association of Medical Sciences from December 2022 to January 2023. These questionnaires targeted medical researchers. Exposure was the medical researchers' perceptions of quantitative indicators for evaluating medical research and researchers. The outcome was psychological well-being, measured using the Japanese version of the World Health Organization-Five Well-Being Index (WHO-5). Multivariable-adjusted logistic regressions were conducted to investigate the association between individual attitudes toward research evaluation and psychological well-being. Stratified analyses by research fields, i.e., clinical, basic, and social medicine, were also performed. RESULTS: A total of 3,139 valid responses were collected. After excluding 176 responses from research fields of other than clinical, basic, or social medicine, 2,963 researchers (2,185 male, 737 female, and 41 other) were analyzed. Prevalence of poor well-being (WHO-5 score <13) was 28.3% in the researchers. The highest number of medical researchers was in clinical medicine (n = 500) followed by basic medicine (n = 217) and social medicine (n = 121). Medical researchers who considered research funding slightly important/not important for researcher evaluation had poorer psychological well-being than those who considered it especially important (slightly important: adjusted odds ratio (aOR) 1.33, 95% confidence interval (CI) 1.03-1.71; not important: aOR 1.53, 95%CI 1.10-2.12). This tendency was stronger among basic medical researchers than clinical or social medical researchers. The research field significantly modified the relationship between research funding received and interaction with poor psychological well-being both additively (P = 0.030) and multiplicatively (P = 0.024). CONCLUSIONS The discrepancy between medical researchers' attitudes toward research evaluation and the current state of research evaluation in their research community may worsen their psychological well-being. The influence of this discrepancy differs among clinical, basic, and social medicine. Appropriate evaluation of medical research and researchers in each field can facilitate improving their psychological well-being via the resolution of this discrepancy.
Humans ; Japan ; Female ; Male ; Cross-Sectional Studies ; Adult ; Research Personnel/statistics & numerical data* ; Middle Aged ; Biomedical Research ; Surveys and Questionnaires ; Mental Health ; Psychological Well-Being ; East Asian People

BACKGROUND: Self-care is increasingly recognized as the foundation of person-centered healthcare and a key driver for simultaneously improving population health outcomes and reducing healthcare expenditures. While the Self-Care Inventory (SCI) has been validated in several languages, Japan lacks a standardized instrument for assessing self-care in the general adult population. Moreover, it remains unclear whether the SCI reflects culturally specific self-care behaviors and retains its psychological measurement properties in non-Western contexts. Addressing both aspects, this study aimed to evaluate the Japanese version of the SCI (JSCI) in terms of its psychometric properties and its association with concrete health behaviors. METHODS: We adapted the JSCI following COSMIN guidelines using forward/backward translation, expert review, and cognitive debriefing. Psychometric evaluation was based on two samples: a nationwide web-based survey (n = 504) and a community-based paper survey (n = 75). Structural validity was examined via CFA; internal consistency via Cronbach's alpha and McDonald's omega; and test-retest reliability via ICCs. Convergent and criterion validity were assessed through correlations with relevant psychological constructs. Measurement invariance and DIF across modes were tested, and associations with five external self-care behaviors were evaluated using AUC. RESULTS: The hypothesized three-factor structure of the JSCI was supported across both administration modes (CFI = 0.926-0.942; SRMR < 0.06), although some subscales had elevated RMSEA. Internal consistency was acceptable to high (α = 0.75-0.85; ω = 0.81-0.92). ICCs indicated moderate to good temporal stability. JSCI scores correlated with self-care efficacy and other related constructs, supporting convergent and criterion validity. Configural invariance was confirmed, and no significant DIF was detected across modes. JSCI scores modestly discriminated individuals engaging in concrete self-care behaviors such as physical activity, strength training, Helicobacter pylori testing, and having a regular primary or dental care provider (AUCs = 0.62-0.80). CONCLUSIONS The JSCI demonstrated satisfactory psychometric properties and structural validity across diverse research settings. Its observed associations with a range of meaningful self-care behaviors support the scale's ecological and practical relevance in the Japanese context. The JSCI may serve as a reliable tool for evaluating and promoting self-care in both research and population health initiatives.
Humans ; Japan ; Self Care/statistics & numerical data* ; Psychometrics ; Male ; Female ; Adult ; Cross-Sectional Studies ; Middle Aged ; Reproducibility of Results ; Surveys and Questionnaires ; Young Adult ; Aged ; Health Behavior ; Translations ; East Asian People

BACKGROUND: Difficulty awakening is a common concern among adolescents and contributes to school absenteeism. Although cross-sectional studies suggest that commuting times, internet usage, and sleep disturbances are associated with school attendance problems, few have specifically focused on adolescents. We aimed to examine the factors contributing to school absenteeism due to difficulty awakening in Japanese high school students. METHODS: In this longitudinal cohort study, data were prospectively collected between 2016 and 2018 from 54 high schools in a prefecture of Western Japan. Tenth-grade students (n = 6,121) without tardiness (n = 5,812) or absences (n = 5,946) at baseline were recruited. The outcome of interest was school absenteeism due to difficulty awakening, which included both tardiness and absences (≥2 days/month). Cox proportional hazards models were used to assess the associations between commuting time and lifestyle factors after adjusting for confounders. RESULTS: The incidence rates of tardiness and absences due to difficulty awakening were 19.3 and 9.6 per 1,000 person-years, respectively. Common risk factors for absenteeism included prolonged internet usage (≥5 h) and dissatisfaction with school. Protective factors for school tardiness included study time and participation in extracurricular sports activities (both ≥2 h). Long commuting time (≥1 h) was associated with a higher risk of school absences. CONCLUSIONS Long commuting times, prolonged internet usage, and poor school satisfaction increased the risk of school absenteeism due to difficulty awakening. Promoting academic engagement and extracurricular activities may help reduce absenteeism. Interventions that increase school satisfaction, such as providing learning opportunities outside of school, supporting extracurricular activities, and improving the school environment, may be effective prevention strategies.
Humans ; Absenteeism ; Japan/epidemiology* ; Adolescent ; Male ; Female ; Prospective Studies ; Schools/statistics & numerical data* ; Students/psychology* ; Longitudinal Studies ; Risk Factors ; Transportation/statistics & numerical data* ; East Asian People