BACKGROUND:Stereoscopic (3D) viewing can induce motion sickness and visual discomfort under specific environmental conditions. Light adaptation is not always linear; preceding light exposure influences subsequent physiological responses (hysteresis). However, hysteresis in 3D viewing has rarely been studied. OBJECTIVE:This exploratory study examined whether physiological responses exhibit hysteresis-history-dependent asymmetries between increasing and decreasing illuminance phases-under combinations of low illuminance, color temperature, and viewing mode. METHODS:Eight healthy adults (age 21.75 ± 0.97 yr) were exposed to stereoscopic video under eight conditions (2 color temperatures × 2 illuminance-change directions × 2 viewing modes). Illuminance was varied in stepwise fashion (10-260 lx). Electroencephalogram (EEG; Fp1/Fp2), electrocardiogram (ECG), and Stabilometry were recorded. Repeated-measures ANOVAs with Benjamini-Hochberg FDR correction and paired Hedges' g effect sizes were computed. RESULTS:Large hysteresis effects were observed for postural sway (Hedges' g = 0.66-1.01) and moderate effects for theta-band EEG (|g| ≈ 0.5-0.65), particularly in peripheral vision under low illuminance. Stabilometry was significantly greater at 10 lx compared to higher illuminances (p < 0.05). The interaction between illuminance and illuminance-change direction was significant for total locus length per unit area (L/A) in peripheral vision under daylight color. CONCLUSIONS:Postural control, but not autonomic function, exhibited strong history dependence in response to illuminance changes during 3D viewing. Findings suggest minimum illuminance guidelines (∼80-100 lx) and consideration of illuminance-ramp rates for VR safety and 3D content design.
Climate change leads to adverse health effects globally, including increased heat-related mortality of the elderly. Besides physiological factors of aging and comorbidities, social isolation is one risk factor associated with adverse health effects of heat. In 2025, the Working Group Environmental Health at Hokkaido University and the Institute of General Practice from University of Cologne held a research workshop to explore joint solutions for climate-resilience in super-aged nations like Germany and Japan. The three-day interactive workshop was held at Hokkaido University, Sapporo, Japan and included a hybrid symposium with external experts as well as intensive exchange between the research groups. Jointly addressing social isolation and heat health risks, was identified as a promising way to increase health systems resilience in times of societal and environmental crisis, especially in super-aged countries. This commentary narratively summarizes the current evidence on interventions targeting social isolation and heat health risks, finding that current interventions aim to protect socially isolated older adults during heat waves, but do not intend to alleviate both, social isolation and heat health risks at a broader scale. Based on the discussions in the workshop this commentary proposes future research opportunities, entailing family-based as well as community-based approaches, which foster social connection throughout the year and are particularly triggered during hot days and heat waves. Further research is needed to co-develop and evaluate such interventions with older adults and their families and communities to increase resilience of societies and health systems.
BACKGROUND:Publicly available aggregate health data can support regional surveillance of cardiometabolic risk, but analyses must address aggregation, ecological inference, and cell suppression or unavailability. Waist circumference and body mass index (BMI) capture related but distinct aspects of adiposity. We evaluated the usefulness and limitations of selected 10th National Database (NDB) Open Data indicators for prefecture-level cardiometabolic surveillance among Specific Health Checkup examinees in Japan. METHODS:We conducted an ecological descriptive analysis of the 10th NDB Open Data. Data were analyzed by prefecture, sex, and 5-year age band among examinees aged 40-74 years. Primary indicators were the percentage meeting the waist circumference criterion (≥85 cm in men, ≥90 cm in women) and the percentage with hemoglobin A1c (HbA1c) ≥6.5%; BMI categories were examined as exploratory indicators. Prefecture-level percentages were internally age-standardized within sex using the age distribution of publicly displayed examinee counts pooled across prefectures for each indicator as the internal standard. Cells displayed as "-" were treated as suppressed/unavailable and not as zero values. RESULTS:Waist circumference criterion data were complete across prefectures, sexes, and age bands. HbA1c ≥6.5% data were complete among men but included suppressed/unavailable cells among women, and BMI indicators had substantial cell suppression/unavailability. The age-standardized percentage meeting the waist circumference criterion ranged from 45.5% in Niigata to 60.6% in Okinawa among men and from 13.7% in Kyoto to 24.0% in Okinawa among women. HbA1c ≥6.5% ranged from 8.3% in Nagano to 11.3% in Miyagi among men and from 3.9% in Kanagawa to 7.8% in Saga among women. Okinawa had the highest percentage meeting the waist circumference criterion in both sexes. Waist-HbA1c correlations were positive in available-cell analyses, but estimates among women and estimates involving BMI were sensitive to cell availability and the prefectures included in the analysis. CONCLUSIONS:The percentage meeting the waist circumference criterion was the most complete and robust descriptive indicator for prefecture-level cardiometabolic surveillance using the 10th NDB Open Data. HbA1c analyses among women and BMI-based analyses require suppression-aware interpretation. Ecological correlations should be interpreted as descriptive co-patterning of aggregate surveillance indicators, not as individual-level associations or evidence of regional determinants. TRIAL REGISTRATION:Not applicable.
BACKGROUND:Reproductive history can be conceptualized as a life-course exposure integrating biological and social factors. Although reproductive factors have been associated with stroke risk and cognitive function, their relationships with structural brain changes remain unclear. Evidence from general population-based studies linking reproductive factors to brain volume, an intermediate marker of cognitive decline, is limited. This study examined whether age at menarche, age at menopause, estrogen exposure duration, and parity are associated with brain volume in postmenopausal women. METHODS:This cross-sectional study included 361 postmenopausal women aged ≥55 years from the Ohasama Study in Japan. Reproductive factors were obtained from a 1998 questionnaire were categorized into quartiles, and MRI data from 2009 to 2019 were analyzed with voxel-based morphometry. Associations were assessed using analysis of covariance adjusted for intracranial volume, age, birth cohort, and BMI. Effect sizes were reported as percent change and standardized effect sizes, with the smallest effect size of interest (SESOI) based on one-year age-related brain volume change. RESULTS:After covariate adjustment, most associations between reproductive factors and brain volume were attenuated. Earlier age at menarche showed a weak trend toward larger temporal lobe volume (β = 0.59 cm3, 95% CI -0.03 to 1.21; p = 0.06), corresponding to a 0.63% change and 0.06 SD, which was comparable to the SESOI (±0.54% or 0.06 SD). Earlier age at menopause was associated with smaller occipital lobe volume (β = -0.52 cm3, 95% CI -1.01 to -0.03; p = 0.04), corresponding to a -1.08% change and 0.10 SD, exceeding the primary SESOI threshold (±0.64% or 0.06 SD), although confidence intervals included effects smaller than the SESOI. No significant associations were found for estrogen exposure or parity. CONCLUSION:Reproductive factors were not associated with moderate or large differences in brain volume in postmenopausal women. The slight, region-specific differences observed were comparable in magnitude to short-term age-related changes. These findings suggest that the clinical significance at the individual level is likely limited. However, subtle associations at the population level cannot be entirely excluded.
BACKGROUND:Hypertension is prevalent and is influenced by modifiable factors. Increasing attention has focused on community-based health promotion. However, studies on the relationship between neighborhood characteristics and hypertension prevalence are limited. This study combined medical claims and geographic information system data to identify neighborhood characteristics associated with hypertension. METHODS:The study population included participants enrolled in the National Health Insurance or Medical Care System for the Elderly in both 2017 and 2021, and their 2021 data were aggregated at the elementary school district level. Hypertension was defined using the International Statistical Classification of Diseases and Related Health Problems-10 codes I10-I15. Neighborhoods were defined by elementary school districts. For each school district, hypertension prevalence, the proportions of participants aged <65 years, 65-74 years, and ≥75 years, and the proportion of men were calculated. Neighborhood characteristics included college graduation rate, area deprivation index, annual average temperature, annual total precipitation, average slope angle, number of destination types, and densities of public places. Quasi-Poisson regression analyses were conducted with the number of hypertension cases as the dependent variable, neighborhood characteristics as explanatory variables, the proportions of participants aged 65-74 years and ≥75 years, and the proportion of men (in the overall analysis) as covariates, and the number of participants as an offset term. For the quasi-Poisson regression analyses, a Bonferroni-adjusted p-value < 0.05 was considered statistically significant. RESULTS:The study covered 424 elementary school districts across 14 municipalities in five prefectures in western Japan. The mean number of participants per district was 2,248 (men: 946, women: 1,302), with an average age of 67 years (men: 66; women: 68). The mean hypertension prevalence was 51% (men: 53%; women: 50%). In the combined and female-only analyses, the neighborhood proportion of university graduates and green space coverage were significantly negatively associated with hypertension prevalence. In the male-only analysis, the proportion of university graduates, green space coverage, and park density showed significant negative associations. CONCLUSIONS:Neighborhood socioeconomic and physical environmental characteristics were associated with hypertension prevalence in Japan, particularly educational attainment and green space coverage, suggesting that social and physical environmental attributes may contribute to community-level cardiovascular health.
BACKGROUND:Heatstroke is a major public health problem during summer, and meteorological conditions, particularly wet bulb globe temperature (WBGT), strongly influence its occurrence. However, even under similar heat conditions, heatstroke risk may vary according to behavioural patterns on weekdays, weekends/holidays, and post-holiday days. This study aimed to examine whether heatstroke-related ambulance transports in Tokyo vary according to day type after adjusting for WBGT. METHODS:We conducted a time-series analysis using daily heatstroke-related ambulance transports in Tokyo, Japan, during the warm season (May-September) from 2015 to 2025. The days were classified as weekday, weekend/holiday, or post-holiday. The WBGT data for seven locations in Tokyo were used, and the highest daily maximum WBGT served as the heat exposure indicator. Modified Poisson regression models were used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) according to day type, adjusting for the WBGT category at lags 0 and 1 and the calendar year. The same models were applied by age group, severity, and place of occurrence. Four sensitivity analyses, including the use of alternative heat exposure indicators and exclusion of the coronavirus disease 2019 period, were conducted. RESULTS:After adjusting for WBGT and calendar year, the occurrence of heatstroke-related ambulance transports differed according to day type. Overall, ambulance transports tended to be more frequent on post-holiday days than on weekdays (RR, 1.08; 95% CI, 0.97-1.22). Among adults aged ≥65 years, transports were more frequent on post-holiday days (RR, 1.13; 95% CI, 1.00-1.28) and less frequent on weekends/holidays (RR, 0.87; 95% CI, 0.79-0.96). Among individuals aged <18 years, transports were markedly more frequent on weekends/holidays (RR, 1.80; 95% CI, 1.61-2.03). Weekend/holiday increases were also observed in mild cases and in public indoor and outdoor spaces and educational institutions, whereas cases in residences and workplaces were less frequent. Sensitivity analyses yielded similar results. CONCLUSIONS:Heatstroke-related ambulance transports in Tokyo varied according to day type even after adjusting for WBGT, with distinct patterns across age groups, severity categories, and places of occurrence. Weekly behavioural patterns may contribute to heatstroke risk and warrant consideration in preventive strategies.
BACKGROUND:Accessible and trustworthy health information sources support informed decisions. Longitudinal evidence on how health information sources influence behavioural changes in community-dwelling populations remains limited. Thus, we examined associations between health information sources and behaviour changes in walking time, balanced meal consumption, and smoking cessation. METHODS:Baseline (2021) and follow-up (2023) survey questionnaires were distributed to residents randomly selected from the 18 residential areas. Health information sources were classified into five categories: print media, television (TV) and radio, the Internet, family and friends, and professionals. Desirable health behaviours were defined as walking for ≥60 min/day; consuming ≥2 meals per day comprising staple grains, main dishes, and side items (SMS); and smoking cessation. Meeting these criteria was classified as good; not meeting them as poor. Improvement was defined as poor at baseline and good at follow-up. Maintenance was defined as good at both surveys. Improvement analyses included participants with poor baseline conditions. Maintenance analyses included those with good baseline conditions. Associations were analysed using multilevel modified Poisson regression models, accounting for clustering within residential areas and adjusting for covariates. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were calculated. RESULTS:Of the 12 119 baseline participants, 6620 (54.6%) completed the follow-up. The most common health information sources were TV and radio (68.5%), the Internet (56.8%), and print media (48.9%). Use of family and friends as information sources was associated with improvement in walking time (RR: 1.19; 95% CI: 1.02-1.39), as was use of professionals (RR: 1.15; 95% CI: 1.03-1.28). Professionals showed a marginal association with sustained walking time (RR: 1.07; 95% CI: 0.99-1.15). TV and radio was associated with improvement in SMS meal consumption (RR: 1.13; 95% CI: 1.02-1.26), while print media was associated with maintenance of SMS meal consumption (RR: 1.05; 95% CI: 1.01-1.08). No sources were related to smoking cessation. CONCLUSIONS:Health information sources showed distinct associations with improved and maintained health behaviours. Interpersonal sources were relevant for improving walking time, while mass media were linked to dietary improvement and maintenance. These findings suggest tailoring health communication strategies to specific health behaviours.
Background: In Japan, community-driven dining spaces known as children’s cafeterias (kodomo shokudo) have increased rapidly. Despite their rapid expansion, the role of social environmental factors in the development of children’s cafeterias, particularly social capital, has received limited empirical attention. We examined the association between social capital and changes in the number of children’s cafeterias in Japan. Methods: We conducted a longitudinal ecological study. The outcome was the change in the number of children’s cafeterias per municipality between 2020 and 2022. Social capital indicators (trust in neighbors, norm of reciprocity, trust in the national government, neighborhood ties, and social participation) were derived from a nationwide internet survey. Results: A total of 512 local municipalities were analyzed. Multiple regression analyses showed that higher neighborhood trust was positively associated with increases in the number of children’s cafeterias, whereas denser neighborhood ties were inversely associated with such increases. Conclusions: The findings suggest that cognitive and structural dimensions of social capital may operate differently in the diffusion of children’s cafeterias. These results indicate that community social contexts are associated with the spread of child-focused initiatives.
BACKGROUND:Previously, several studies have focused on the correlation between SNPs of the excision repair cross-complementation group 5 (ERCC5) gene and breast cancer susceptibility, and the rs17655 (Asp1104His) has been mostly studied among many SNPs of ERCC5 gene. However, contradictory results also existed among these published articles. So, we performed this meta-analysis to evaluate the relationship between the rs17655 of ERCC5 gene and the susceptibility to breast cancer. METHODS:All analyses in this meta-analysis were performed using Stata 15.0 version software. The heterogeneity test was performed using the chi-square-based Q-test and the I-square test. Sensitivity analysis was performed to estimate the influence of the combined ORs caused by individual data. Begg's funnel plot method was used for the publication bias testing. RESULTS:We found a significant relationship between the rs17655 of ERCC5 gene and the breast cancer risk for the dominant model, OR (95% CI) = 1.24 (1.01-1.52), p = 0.036. But we found no significant association between the rs17655 and breast cancer risk for the recessive model (OR = 1.03, 95% CI = 0.80-1.32, p = 0.825) and the allele model (OR = 1.16, 95% CI = 0.98-1.38, p = 0.083). No statistically significant association were found between the ERCC5 gene rs17655 and the risk of breast cancer for the dominant model observed in Caucasian populations (pooled OR = 1.03, 95%CI = 0.91-1.18), in African populations (pooled OR = 1.55, 95%CI = 0.77-3.12) and in Asian population (pooled OR = 1.76, 95%CI = 0.755-4.12). No publication bias was observed for three genetic models (P = 0.061 for the dominant model, P = 0.825 for the recessive model, P = 0.118 for the allele model). CONCLUSIONS:Carriers with rs17655 minor allele have higher susceptibility to breast cancer for the dominant model. But no significant relationship was observed between rs17655 and breast cancer susceptibility in Caucasian, African, and Asia populations.
BACKGROUND:The coronavirus disease 2019 (COVID-19) pandemic highlighted poor health literacy (HL) as an underestimated public health problem. This study aimed to examine whether COVID-19-related HL and general HL were differentially associated with mental health problems. METHODS:A questionnaire survey was conducted among residents of Japanese metropolitan areas during the resurgence phase of the pandemic. Data from 1,482 participants were analyzed. COVID-19-related HL was assessed by participants' perceived difficulty in understanding COVID-19-related information and recommendations. General HL was measured using the Communicative and Critical Health Literacy scale. Mental health outcomes included psychological distress, mood and anxiety disorders, and COVID-19-related anxiety. Multiple logistic regression analyses were conducted to estimate odds ratios (ORs) and 95% confidence intervals (CIs) per one-standard deviation increase in each HL measure, adjusting for age, sex, education, income, work status, self-rated health, and the other HL measure. RESULTS:The correlation coefficient between the two HL measures was 0.195. Higher COVID-19-related HL was associated with decreased risks of mental health problems; the ORs were 0.70 (95% CI, 0.62-0.78) for psychological distress, 0.76 (95% CI, 0.66-0.88) for mood and anxiety disorders, and 0.66 (95% CI, 0.53-0.81) for COVID-19-related anxiety. General HL was not associated with mental health problems; the corresponding ORs were 0.95 (95% CI, 0.85-1.06), 0.90 (95% CI, 0.79-1.03), and 1.11 (95% CI, 0.90-1.36), respectively. CONCLUSIONS:Higher COVID-19-related HL, but not general HL, was associated with decreased risks of mental health problems.
Background: Environmental endocrine disruptors (EEDs), endocrine-interfering pollutants, attract attention for potentially affecting heart diseases via epigenetics. Nonylphenol (NP), a classical representative of endocrine-disrupting chemicals, has previously been demonstrated by our research group to induce myocardial fibrosis in rats. LncRNA, a gene regulator, mediates EED-induced heart cell damage and fibrosis. Objective: This study aimed to investigate the role of long noncoding RNA OIP5 antisense RNA 1 (lncRNA OIP5-AS1) knockdown in NP-induced myocardial fibrosis. Methods: Small interfering RNA (siRNA) transfection was used to interfere with the expression of lncRNA OIP5-AS1 in H9C2 cells. Lactate dehydrogenase (LDH), cell Counting Kit-8 (CCK-8), transwell, quantitative real time polymerase chain reaction (qRT-PCR), and Western blot assays were employed to detect cell membrane integrity, proliferation, migration ability, and the expression of fibrosis-related genes/proteins in H9C2 cells. This process was also validated in Sprague Dawley (SD) rats. Results: The expression of fibrosis-related factor mRNA and proteins in H9C2 cells increased, and the expression of lncRNA OIP5-AS1 was significantly upregulated after 24 h of exposure to 70 µmol/L NP. The knockdown of lncRNA OIP5-AS1 did not show differential changes in LDH activity across treatment groups. However, the knockdown of lncRNA OIP5-AS1 significantly attenuated NP-induced proliferation and migration abilities of H9C2 cells and inhibited the increase in the expression of fibrosis-related factor mRNA/proteins caused by NP. This suggested that the interference with lncRNA OIP5-AS1 expression inhibited the NP-induced myocardial fibrosis in H9C2 cells. In vivo results suggested that NP exposure and isoproterenol hydrochloride groups in rats showed accumulation of myocardial collagen fibers in the interstitial space, increased distribution and content of collagen fibers, and elevated expression of fibrosis-related proteins. The distribution range, content of collagen fibers, and expression of fibrosis-related proteins significantly reduced in rats with lncRNA OIP5-AS1 knockdown exposed to NP compared with those in the NP group. Conclusions: The expression of lncRNA OIP5-AS1 was upregulated in NP-treated H9C2 cells, rat hearts, and myocardial fibrosis model rats. Knockdown of lncRNA OIP5-AS1 was associated with attenuated NP-induced myocardial fibrosis and reduced collagen deposition.
BACKGROUND:Nitrogen dioxide (NO2) and ozone (O3) exposure is associated with alterations in liver function, but epidemiological evidence in pregnant women remains limited, especially regarding the combined effects. This study aimed to investigate the associations of exposure to NO2 and O3 with maternal liver function and their roles in the combined effect of air pollutant mixture. METHODS:A birth cohort study with 11,909 pregnant women was conducted in Shenzhen, China. Exposure concentration of air pollutants during the first trimester were assessed based on the residential addresses of the pregnant women. Generalized additive model was used to analyze the association of NO2 and O3 exposure with maternal liver function. Furthermore, quantile G-computation model was used to investigate the combined effects of air pollutant mixture and the contribution of each pollutant. RESULTS:Each 10 µg/m3 increase in first-trimester NO2 exposure was associated with elevated alanine aminotransferase (ALT) and total bilirubin (TBIL) in both the second trimester (ALT: 15.45%, 95% CI: 10.12%, 21.04%; TBIL: 6.69%, 95% CI: 3.75%, 9.72%) and third trimester (ALT: 3.89%, 95% CI: 0.32%, 7.59%; TBIL: 9.27%, 95% CI: 6.52%, 12.10%). For O3, first-trimester exposure showed a positive association with second-trimester TBIL (2.03%, 95% CI: 1.25%, 2.81%), but was inversely associated with third-trimester ALT (-2.73%, 95% CI: -3.86%, -1.58%) and TBIL (-0.81%, 95% CI: -1.45%, -0.17%). These associations remained significant in the two-pollutant model. The Qgcomp analysis revealed that a one-quartile increase in the air pollutant mixture was associated with a 2.05% (95% CI: 0.56%, 3.56%) increase in third-trimester TBIL, with NO2 accounting for 55.6% of the positive weight in the model. CONCLUSIONS:First-trimester NO2 exposure was associated with elevated maternal liver function biomarkers in both the second and third trimesters, while O3 showed trimester-dependent associations. Exposure to air pollutant mixture was associated with increased third-trimester TBIL, and NO2 may be the predominant relative contributor. These findings highlight the need for further studies and public health attention to air pollution exposure during pregnancy to protect maternal and fetal health.
Background: Bisphenol A (BPA) and its structural substitutes, bisphenol S (BPS) and bisphenol F (BPF), are widely used endocrine-disrupting chemicals. While BPA exposure has been linked to metabolic disorders, evidence regarding BPA substitutes in children remains limited, particularly in Southeast Asia. Methods: We conducted a cross-sectional study among Thai children and adolescents aged 7-18 years classified as normal weight (NW) or overweight/obese (OW/OB). Urinary BPA, BPS, and BPF concentrations were measured using liquid chromatography-tandem mass spectrometry. Anthropometric measurements, body composition, fasting glucose, insulin, lipid profiles, and liver enzymes were assessed. Associations between urinary bisphenol concentrations and metabolic parameters were analyzed using multivariable regression models. Results: A total of 114 participants were included (26 normal weight and 88 overweight/obese). BPA was detected in all (100%) urine samples, whereas BPS and BPF were detected in 50.0% and 53.6% of participants, respectively. Creatinine-adjusted urinary concentrations of BPA, BPS, and BPF did not differ significantly between NW vs. OW/OB. Higher urinary BPS and BPF concentrations were associated with higher fasting insulin levels (aGMR 1.13; 95%CI 1.05-1.20; p = 0.001) and higher LDL cholesterol levels (aGMR 5.82; 95%CI 0.52-11.11; p = 0.032), respectively. In contrast, higher urinary BPA concentrations were associated with lower fasting insulin levels (aGMR 0.77; 95%CI 0.66-0.90; p = 0.001). Conclusions: Exposure to BPA and its substitutes, BPS and BPF, were associated with distinct metabolic alterations independent of weight status. BPS was associated with hyperinsulinemia, while BPF was associated with elevated LDL cholesterol.
Background: As population aging progresses in Japan, an increasing number of older wheelchair users regularly travel in the rear space of motor vehicles. Poor seatbelt fit is the main cause of severe or fatal injuries in collisions. The current study sought to examine the potential risks regarding seatbelts for wheelchair users in Japan using national statistics, and to elucidate the mechanisms of injuries among wheelchair users involved in frontal collisions using sled tests. We propose a restraint system for wheelchair users traveling in vehicles. Methods: To identify cases of collisions involving vehicles with wheelchair user passengers, national police database was examined. A sled test representing a 48 km/h frontal collision with a Hybrid III AF05 dummy was used to examine kinematics at collision and biomechanical parameters of wheelchair users. We examined three test conditions (1. generally used seatbelt path for standard wheelchairs; 2. close seatbelt path for standard wheelchair; 3. close seatbelt path for sturdy wheelchair). Results: According to a national database in Japan, a seatbelt was worn in most cases of fatalities and casualties among wheelchair user passengers. In sled test condition 1, the dummy moved forward and the lap belt compressed the abdomen. High values were observed for head injury criterion and neck injury criterion. In condition 2, the dummy moved forward and fell because the wheelchair seat collapsed. In all conditions, high values for chest deflections (51.3 to 53.8 mm) were caused by high shoulder-belt load (8,217 to 8,660 N). Conclusions: Indications for future design of safety restraint system were provided as follows: both the shoulder and lap belts would be correctly positioned across the bony parts of the shoulder and pelvis, respectively; a force limiter would be installed in the restraint system to reduce shoulder belt loads; a sturdy wheelchair and adequate tie-down system that can resist applied forces would be used.
BACKGROUND:The long-term impact of dynapenic abdominal obesity (D/AO)-the coexistence of muscle weakness and central adiposity-on physical, psychological, and cognitive multidimensional multimorbidity (mMM) remains unclear. METHODS:We analyzed longitudinal data from 8,311 adults aged ≥45 [China Health and Retirement Longitudinal Study (CHARLS), n = 4,887; Health and Retirement Study (HRS), n = 3,424] without baseline mMM (i.e., having at most a single-domain impairment), followed biennially for up to 4 years. To account for cross-cultural heterogeneity, analyses were conducted independently per cohort. Three mMM patterns-physical-psychological (PP-MM), physical-cognitive (PC-MM), and physical-psychological-cognitive (PPC-MM)-were constructed using chronic diseases, depressive symptoms, and cognitive tests. Multivariate regression assessed the risk and trajectory of mMM associated with D/AO, and continuous-time Markov multi-state models were utilized to estimate transition probabilities. RESULTS:In both the CHARLS and HRS cohorts, D/AO was significantly associated with an increased risk of all three specific mMM patterns compared to the non-dynapenic/non-abdominal obesity group, with the strongest association observed for PPC-MM [OR = 2.475 (1.100-5.002) in CHARLS; OR = 5.712 (2.009-14.882) in HRS]. Longitudinal analysis revealed that D/AO was associated with a higher likelihood of entering "incident/worsening" trajectories (RRR = 2.001, P = 0.014 in CHARLS; RRR = 2.507, P = 0.013 in HRS) and an elevated probability of progressing from PC-MM to complex PPC-MM. Notably, age significantly modified these associations, with risk magnitudes markedly higher among individuals aged <65 years (e.g., PP-MM in HRS: OR = 6.98, 95% CI: 1.85-26.31; PC-MM in CHARLS: OR = 4.39, 95% CI: 1.95-9.89). Pooled analyses and multiple sensitivity tests confirmed the robustness of the D/AO "risk gradient effect" across diverse populations, without significant cohort interactions. CONCLUSION:D/AO is longitudinally associated with a higher incidence of mMM and less favorable health trajectories, particularly among individuals aged <65 years. These findings suggest that integrating muscle strength and abdominal adiposity assessments into primary care may offer potential value for early risk stratification. While the efficacy of targeted interventions warrants further verification in interventional studies, focusing on the D/AO phenotype provides a proactive perspective for mitigating the multidimensional multimorbidity burden in aging populations.
BACKGROUND:Stroke is a leading cause of death in China. While chronic kidney disease is a known stroke risk factor, quantitative evidence on the graded relationship between estimated glomerular filtration rate (eGFR) and stroke risk in the Chinese population remains limited. METHODS:This study integrated individual-level data from the China Health and Retirement Longitudinal Study (CHARLS), including a prospective cohort (n = 7,786, follow-up from 2015 to 2020) and a cross-sectional cohort (n = 8,467, 2011 wave), alongside a hospital-based cross-sectional dataset (n = 1,649, including 839 patients with stroke). The association between eGFR (modeled as continuous and categorical variables) and stroke was assessed using multivariable Cox proportional hazards models. Additionally, Kaplan-Meier survival curves and log-rank tests were also performed. The dose-response relationship was examined using restricted cubic spline (RCS) analysis. Sensitivity analyses using multiple imputation were conducted. RESULTS:Reduced eGFR was consistently associated with higher stroke risk across all datasets. In the fully adjusted prospective model, each 1 mL/min/1.73 m2 decrease in eGFR was associated with a 1.3% increase in stroke hazard (HR = 1.013, 95% CI: 1.006-1.020). Consistent associations were observed in the cross-sectional CHARLS cohort (OR = 1.020, 95% CI: 1.008-1.032) and the hospital cohort (OR = 1.026, 95% CI: 1.019-1.033). Kaplan-Meier curves showed significantly lower stroke-free survival in lower eGFR quartiles (log-rank P < 0.001). RCS analyses confirmed a linear inverse relationship in all datasets (P for overall < 0.001; P for nonlinear > 0.05). Subgroup analyses showed no significant effect modification by key demographics or comorbidities. Sensitivity analyses confirmed the robustness of the findings. CONCLUSION:Reduced eGFR is significantly and independently associated with increased stroke risk among Chinese adults aged ≥45 years, exhibiting a clear dose-response relationship. These findings support the potential utility of integrating renal function monitoring into stroke risk assessment and prevention strategies.
Background: Research over the past decade has indicated that exposure to per- and polyfluoroalkyl substances (PFAS) disrupts the intestinal barrier, potentially contributing to the development of gastrointestinal disorders. More recently, constipation has been hypothesized as one such outcome. However, epidemiological studies examining this association remain limited. Methods: We analyzed data from 17,686 mothers and their children from the Japan Environment and Children's Study, a Japanese birth cohort study. We used maternal plasma samples collected during pregnancy to determine PFAS concentrations. Of the 28 PFAS compounds analyzed, we included seven compounds that were quantified in more than 80% of the samples. We assessed functional constipation in children at ages 3 and 4 using caregiver-completed questionnaires based on the Rome III criteria. Logistic regression models were used to examine associations between maternal PFAS concentrations and childhood functional constipation, applying a Bonferroni-corrected significance threshold of P < 0.0035 to account for multiple comparisons. Results: Functional constipation was observed in 11.3% of children at age 3 and 9.8% at age 4. After adjusting for potential confounders, we observed no significant associations between any of the seven maternal PFAS concentrations and functional constipation in children at 3 years of age. However, at 4 years, perfluorooctanoic acid (PFOA) concentrations were significantly associated with functional constipation, with an adjusted odds ratio of 1.13 (95% confidence interval: 1.05-1.21, P = 0.00057) per doubling of concentration. The remaining six PFAS compounds showed no significant associations at 4 years. Conclusions: The single positive association between maternal PFOA concentration and functional constipation at 4 years of age is unlikely to reflect a true causal relationship, given limited biological plausibility. Our results do not provide evidence of an association between prenatal PFAS exposure and functional constipation in children, although further investigation is warranted.
BACKGROUND:The coronavirus disease 2019 (COVID-19) pandemic has imposed significant psychological stress worldwide. Although many studies have examined the mental health impacts during the pandemic's early phase, evidence from the late phase remains limited. This study investigated the associations between COVID-19-related anxiety and sense of coherence (SOC) with psychological distress among rural residents during the pandemic late phase in Japan. METHODS:This community-based cross-sectional study was conducted from July 2022 to March 2023, the late phase of the COVID-19 pandemic. The participants were residents of rural communities in the Shimane Prefecture, Japan. They were recruited through a health check-up program arranged by a cooperative organization for farmers. Psychological distress was assessed using the Kessler 6-item Psychological Distress Scale (K6); COVID-19-related anxiety and SOC were assessed using self-administered questionnaires. Multivariable logistic regression analyses were performed to examine the associations between pandemic-related anxiety, SOC, and psychological distress after adjusting for age, sex, subjective health status, and communicative health literacy. RESULTS:Of the 1,310 individuals who underwent health checkups, 743 agreed to participate in the study, and 664 who completed all questionnaires were included in the final analyses. Psychological distress (K6 ≥ 5) was observed in 29.2% of participants and was more prevalent among younger adults. Fear of infection (OR = 1.32, 95% confidence interval [CI]: 1.05-1.68), stress related to mask wearing (OR = 1.35, 95% CI: 1.10-1.68), and concern about reduced income (OR = 1.32, 95% CI: 1.08-1.61) were associated with higher odds of psychological distress. Higher SOC was inversely associated with psychological distress. CONCLUSIONS:During the late phase of the COVID-19 pandemic, several COVID-19-related anxiety factors, particularly fear of infection, stress related to mask wearing, and concern about reduced income, were associated with psychological distress among rural residents. Higher SOC was associated with lower psychological distress, suggesting that strengthening individual and community resilience may be important for mitigating the mental health impact of prolonged pandemic conditions in rural settings.
Background: Gender disparities in the intention to leave research careers after marriage have not been investigated. This study aimed to clarify the gender-specific associations of marital status and nurturing children with the intention to leave research careers among medical researchers. Methods: A cross-sectional study was conducted from December 2022 to January 2023. The study was based on a web-based survey targeting medical researchers affiliated with 141 Japanese academic societies. Participants who disagreed with continuing their research careers were classified as intending to leave. Multivariable-adjusted logistic regression analysis was used to evaluate the gender-specific association of marital status and having children with the intention to leave research careers. Results: Among 3,009 participants, 812 (27.0%) were women, and 342 (11.4%) expressed an intention to leave. A total of 2,481 participants (82.5%) were married, and 2,267 (75.3%) had children. Marital status was associated with intention to leave research careers in opposite directions for men and women, with significant interactions on both multiplicative (P = 0.015) and additive (P = 0.001) scales. Specifically, married men had a significantly lower intention to leave compared with unmarried men (adjusted odds ratio [aOR] 0.63, 95% confidence interval [CI]: 0.40-0.97). In contrast, among women, marriage was associated with a higher intention to leave compared with being unmarried (aOR 1.41, 95% CI: 0.86-2.32), although this increase was not significant. In post hoc subgroup analyses by medical license status, the gender-specific association between marital status and intention to leave research careers was more evident among medical doctors (MDs) than non-MDs, among whom the proportion reporting intention to leave was lower (4% to 6% across groups). However, estimates among non-MD researchers were imprecise due to the small number of events. Similar gender disparities were observed for having children, although the interaction did not reach statistical significance (P for additive interaction = 0.083). Conclusions: The present results suggest that marital status showed opposite associations with intention to leave research careers between men and women, a pattern primarily observed among MD researchers. Our finding highlights the need to consider gender difference when developing strategies to support retention of medical researchers.
Background: Little is known about smoking and alcohol consumption after high school in Japan. This study examined factors associated with smoking and risky drinking among Japanese university students, focusing on sex-related differences. Methods: A cross-sectional web-based survey was conducted among students from five Japanese universities. A total of 253 men and 510 women anonymously completed questionnaires assessing smoking, alcohol use, substance-related behaviors, and depressive symptoms. Logistic regression using penalized regression methods were performed to determine factors associated with smoking and risky drinking. Results: Overall, 7.7% students reported smoking and 25.6% were classified as risky drinkers. Peer smoking was strongly associated with current smoking in men (odds ratio [OR]: 4.58) and women (OR: 2.45). Family smoking and depressive symptoms were associated with smoking only among women, indicating a sex-specific pattern. Regarding risky drinking, common associated factors in both sexes included alcohol-related negative outcomes (OR: 5.83 for men, 5.49 for women) and current smoking (OR: 3.83 for men, 4.86 for women). Among men, additional factors associated with risky drinking were living alone (OR: 2.96) and mixing alcohol with energy drinks (OR: 4.53). Conclusions: After the age of 20, the rates of smoking and risky drinking might increase sharply among Japanese young adults. Sexspecific patterns indicate that male behaviors are shaped by external invitations and living situations, whereas female behaviors are linked to familial and psychological factors.
