BACKGROUND: Although social interaction and social support during the "new normal" due to coronavirus disease 2019 (COVID-19) may be related to presenteeism, the effect between these factors has not been clear for Japanese workers. The aim of this study was to describe the presenteeism of Japanese workers with reference to social interaction and social support following the lifestyle changes due to COVID-19 and to assess whether social interaction and social support affected their presenteeism. METHODS: The data were obtained from internet panel surveys from October 2020. Descriptive statistics were calculated, and multiple linear regression was conducted using the data from the first, fourth and fifth surveys, which were conducted during October to November 2020, July to August 2021, and September to October 2021, respectively. To measure presenteeism, questions from "absenteeism and presenteeism questions of the World Health Organization's Heath and Work Performance Questionnaire", short version in Japanese was utilized. Multiple linear regressions were conducted to investigate the effects of social interaction and social support-related factors on presenteeism. RESULTS: A total of 3,407 participants were included in the analysis. The mean score of absolute presenteeism from the fifth survey was 58.07 (SD = 19.71). More time spent talking with family, a larger number of social supporters and a higher satisfaction level for social support were associated with a higher absolute presenteeism score. CONCLUSIONS Our results suggested that social support reduced the presenteeism of the Japanese workers during the "new normal" due to the COVID-19 pandemic. Social interaction with family also relieved presenteeism.
Humans ; Japan/epidemiology* ; Social Interaction ; Pandemics ; Presenteeism ; COVID-19/epidemiology*

PURPOSE: The rapid development of winter sports requires investigation on injuries in Chongli district, Zhangjiakou city, one of the ski sites of the 2022 Winter Olympics. Careful evaluation is required to observe which injuries are caused under what circumstances, and then we can make corresponding preventive measures and recommendations based on the results. METHODS: In this retrospective study, the data of injury cases at ski resorts in China (Chongli district) and Japan were analyzed to provide a reference for the ongoing injury prevention at ski resorts. We collected data on injuries at Wanlong and Fulong ski resorts in Chongli district during the 2017-2018 and 2018-2019 ski seasons. We referred to the skiing injury report issued in February 2020 of a nationwide ski safety statistical service - Japan Ski Safety Association. The causes of injury and specific injured body parts were analyzed based on the data of Chinese and Japanese ski resorts. Statistical significance has been calculated using the Chi-square test. RESULTS: During the 2019-2020 ski season in Japanese ski resorts, the number of reported injuries per 10,000 skiers was 0.93, of which 457 (17.3%) were over 50 years old, accounting for a large proportion of injuries, meanwhile in Chongli ski resort, the injury rate of skiers aged 50 and over was 7.1%. The knee joint (23.7% at Wanlong ski resort and 28.4% in Japanese ski resorts) was the most injured body part among Chongli and Japanese skiers. Among snowboarders, shoulder joint injury (17.7% in Japanese ski resorts) was the most common, and injury on hands and fingers (16.3% in Wanlong ski resorts) was the most common. Head injury rates are similar in Chongli, China and Japanese ski resorts (8.2% and 8.7%, respectively). CONCLUSION Our analysis demonstrated that injury data recorded among young skiers was higher in Chinese ski resorts (Chongli district) than that in Japanese ski resorts, and elderly skiers made up a larger proportion of skiing injuries in Japanese resorts. Thus, according to our research, the protection of knee joints, shoulder joints, and hands and fingers should be taken seriously. It should pay attention to the teaching of ski poles (for finger protection), and use protective devices such as knee pads, helmets, etc.
Aged ; Humans ; Middle Aged ; Retrospective Studies ; Athletic Injuries/prevention & control* ; Skiing/injuries* ; Japan/epidemiology* ; China/epidemiology*

BACKGROUND: Heated tobacco product (HTP) use has increased substantially between 2016 and 2017 in Japan. This study aims to clarify how HTP use (IQOS, Ploom, and glo) spread across the different combustible cigarette smoking statuses during 2015-16 and 2017-18 in Japan. METHODS: We compared the two periods of (i) 2015 to 2016 (N = 5,366) and (ii) 2017 to 2018 (N = 3,422) from a longitudinal study randomly sampling members from the Japan "Society and New Tobacco" Internet Survey (JASTIS). Multivariable logistic regression models for current HTP use in the previous 30 days by combustible cigarette smoking status in the previous year were used adjusting for socio-demographic factors. RESULTS: HTP use increased by 10 times in the 2017-18 cohort compared with the 2015-16 cohort according to the adjusted odds ratio (95% confidence interval) for current HTP use as 10.2 (7.03-14.8). According to smoking status, significantly higher adjusted ORs (95% CIs) of current HTP use for the after period were observed: 2.60 (1.37-4.94) for never smokers, 7.82 (3.64-16.8) for former smokers, 21.1 (5.73-77.9) for current smokers with intention to quit, and 17.0 (9.58-30.3) for current smokers without intention to quit. CONCLUSION During 2015 to 2018 in Japan, HTP use dramatically increased in all subgroups except for never smokers.
Humans ; Japan/epidemiology* ; Longitudinal Studies ; Tobacco Products ; Tobacco ; Cigarette Smoking ; Surveys and Questionnaires

BACKGROUND: Recent studies indicate that the timing of introduction of potentially allergenic food is crucial for the development of food allergy in children. This cross-sectional study aimed to clarify the reality of allergen food intake in a general population of young children in Japan. METHODS: A questionnaire survey of caregivers was conducted at health checkups for 1.5-year (18-month)-old and 3-year-old children in the fall of 2020. The caregivers were asked about (1) the presence/absence of allergic disease symptoms based on the ISAAC questionnaire, and (2) foods that caregivers avoided giving their children. Ordinal logistic regression analyses were periformed to determine factors associated with food avoidance. RESULTS: Questionnaires were distributed to 1720 caregivers, and 1603 (93%) responded. The responders consisted of 771 and 832 caregivers who participated in 1.5-year-old and 3-year-old checkups, respectively. The prevalence of allergic diseases was comparable to recent epidemiological studies in Japan, indicating that the population may be representative. At 1.5 years old, more than 50% of the children were not exposed to peanuts, tree nuts, fish eggs, shellfish, and buckwheat. At 3 years old, the avoidance rates of the foods had decreased but were still between 18.8% and 32.0%. On the other hand, the avoidance rates of chicken egg and cow's milk, the top 2 common allergenic foods in Japan, were much lower at 2.8% and 1.5% at 1.5 years, and they decreased to 1.4% and 0.7% at 3 years old, respectively. Ordinal logistic analysis showed that avoidance of chicken egg, cow's milk, and wheat was associated with food allergy diagnosis and chicken egg avoidance with eczema, but avoidance of other foods showed no associations with any risk factors for food allergy. CONCLUSION Caregivers avoided giving various foods, independent of allergy risk factors, to their young children. Since delayed introduction of an allergenic food has been reported to increase the risk of developing an allergy to the food, the results warrant future investigation of the development of food allergies in relation to current eating habits and recommendations.
Female ; Animals ; Cattle ; Humans ; Cross-Sectional Studies ; Japan/epidemiology* ; Food Hypersensitivity/complications* ; Risk Factors ; Food ; Allergens

BACKGROUND: Many previous studies have reported COVID-19 vaccine effectiveness, but there are few studies in Japan. This community-based, retrospective observational study investigated the association between vaccination status and COVID-19-related health outcomes in COVID-19 patients by SARS-CoV-2 variant type. METHODS: The study participants were 24,314 COVID-19 patients aged 12 or older whose diagnoses were reported to the Nara Prefecture Chuwa Public Health Center from April 2021 to March 2022, during periods when the alpha, delta, and omicron variants of COVID-19 were predominant. The outcome variables were severe health consequences (SHC) (i.e., ICU admission and COVID-19-related death), hospitalization, and extension of recovery period. The explanatory variable was vaccination status at least 14 days prior to infection. Covariates included gender, age, population size, the number of risk factors for aggravation, and the number of symptoms at diagnosis. The generalized estimating equations of the multivariable Poisson regression models were used to estimate the adjusted incidence proportion (AIP) and 95% confidence interval (CI) for each health outcome. We performed stratified analyses by SARS-CoV-2 variant type, but the association between vaccination status and COVID-19-related health outcomes was stratified only for the delta and omicron variants due to the small number of vaccinated patients during the alpha variant. RESULTS: Of the 24,314 participants, 255 (1.0%) had SHC; of the 24,059 participants without SHC, 2,102 (8.7%) were hospitalized; and of the 19,603 participants without SHC, hospitalization, and missing data on recovery period, 2,960 (15.1%) had extension of recovery period. Multivariable Poisson regression models showed that regardless of SARS-CoV-2 variant type or health outcome, those who received two or more vaccine doses had significantly lower risk of health outcomes than those who did not receive the vaccine, and there was a dose-response relationship in which the AIP for health outcomes decreased with an increased number of vaccinations. CONCLUSION A higher number of vaccinations were associated with lower risk of COVID-19-related health outcomes, not only in the delta variant but also in the omicron variant. Our findings suggest that increasing the number of COVID-19 vaccine doses can prevent severe disease and lead to early recovery of patients not requiring hospitalization.
Humans ; COVID-19/prevention & control* ; SARS-CoV-2 ; COVID-19 Vaccines ; Japan/epidemiology* ; Independent Living ; Outcome Assessment, Health Care

BACKGROUND: Few prospective studies have investigated the association between paternal occupational exposures and risk of infant congenital heart defects (CHDs). We investigated the associations between paternal occupational exposures, frequency of use, and concurrent or sequential exposure to a mixture of compounds and the risk of infant CHDs. METHODS: Our study examined 28,866 participants in the Japan Environment and Children's Study. Logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) associated with paternal occupational exposures during the 3 months until pregnancy was noticed after adjustment for potential confounding factors of the infant CHDs. CHD diagnosis was ascertained from medical record. RESULTS: In total, 175 were diagnosed with infant CHDs. The number of fathers who were exposed to the following substances at least once a month were: 11,533 for photo copying machine/laser printer, 10,326 for permanent marker, 8,226 for soluble paint/inkjet printer, 6,188 for kerosene/petroleum/benzene/gasoline, 4,173 for organic solvents, 3,433 for chlorine bleach/germicide, 2,962 for engine oil, 2,931 for insecticide, 2,460 for medical sterilizing disinfectant, 1,786 for welding fumes, 1,614 for dyestuffs, 1,247 for any products containing lead-like solder, 986 for herbicide, 919 for radiation/radioactive substances/isotopes, 837 for lead-free solder, 341 for microbes, 319 for formalin/formaldehyde, 301 for agricultural chemical not listed above or unidentified, 196 for general anesthetic for surgery at hospital, 171 for anti-cancer drug, 147 for chromium/arsenic/cadmium, 88 for mercury and 833 for other chemical substances. Paternal occupational exposure regularly to photo copying machine or laser printer and soluble paint/inkjet printer were associated with higher risks of infant CHDs: the adjusted ORs (95%CIs) were 1.38 (1.00-1.91) and 1.60 (1.08-2.37), respectively. The higher risks were also observed for occasional exposure to engine oil, any products containing lead-like solder lead-free solder, and microbes; the adjusted ORs (95%CIs) were 1.68 (1.02-2.77), 2.03 (1.06-3.88), 3.45 (1.85-6.43), and 4.51, (1.63-12.49), respectively. CONCLUSIONS Periconceptional paternal occupational exposure was associated with a higher risk of infant CHDs. Further studies using biomarkers of the association between paternal occupational exposure and infant CHDs are warranted.
Male ; Humans ; Infant ; Child ; Japan/epidemiology* ; Prospective Studies ; Risk Factors ; Case-Control Studies ; Occupational Exposure/adverse effects* ; Heart Defects, Congenital/epidemiology* ; Fathers

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic may have increased the rate of presenteeism among front-line physicians. Presenteeism is the term used to describe attendance at work despite ill health that would normally prompt rest or absence from work. This study aimed to examine the associations between COVID-19 clinical practice and presenteeism among physicians. METHODS: A cross-sectional study was conducted from December 2021 to January 2022. The questionnaires were distributed to 21,737 employed physicians who were members of the Japan Medical Association. Presenteeism was measured by the Work Functioning Impairment Scale. Multiple logistic regression analysis was used to evaluate the association between COVID-19 clinical practice and presenteeism. RESULTS: Overall, 3,968 participants were included in the analysis, and presenteeism was observed in 13.9% of them. The rate of presenteeism significantly increased with both the number of COVID-19 patients treated and the percentage of work time spent treating these patients (both P values for trend < 0.001). In comparison to those not currently engaged in the treatment of COVID-19 patients, presenteeism was significantly higher among front-line (adjusted odds ratio [aOR] = 1.71, 95% confidence interval [CI]: 1.16-2.53) and second-line physicians supporting those in the front-line (aOR = 1.45, 95% CI: 1.17-1.78). There was no association between involvement in COVID-19 vaccination services and presenteeism. CONCLUSIONS The burden on front-line and second-line physicians in COVID-19 clinical practice must be minimized. Employed physicians also need to recognize the importance of communicating with their workplaces about presenteeism.
Humans ; COVID-19/epidemiology* ; Presenteeism ; Japan/epidemiology* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Physicians ; Surveys and Questionnaires

BACKGROUND: Individual-level social capital is an important determinant of older adults' long-term care needs; however, there is scant evidence regarding community-level social capital. Therefore, we investigated the association between community-level social capital and the prevalence of the need for long-term care among older adults. METHODS: Between January and February 2018, a cross-sectional survey was conducted among all older adults (n = 13,558) aged 65 to 74 years in a rural municipality in Japan (total population, n = 72,833). A self-reported questionnaire was used to identify community-level social capital, comprising civic participation, social cohesion, and reciprocity. A multilevel logistic regression analysis was performed to estimate the odds ratios of the need for long-term care and a decline in social activity competence as assessed by instrumental activities of daily living. For the analysis, the community levels were divided into 76 voting districts and adjusted for daily life, lifestyle, socioeconomic status, health conditions, and the three social capital subscale scores at the individual level. RESULTS: After adjusting for the covariates, we observed a tendency that a higher community level of reciprocity was associated with a lower prevalence of long-term care needs (OR: 0.86, 95% confidence interval: 0.75-1.00), whereas a high community level of social cohesion was associated with a significantly reduced decline in instrumental activities of daily living (OR per standard deviation increase: 0.87, 95% confidence interval: 0.79-0.96). No significant association was found with civic participation. Similarly, individual-level social capital was associated with the need for long-term care and decline in instrumental activities of daily living. CONCLUSIONS Our findings suggest that good community-level reciprocity or social cohesion as well as good individual social capital status may help prevent the need for long-term care among older adults.
Humans ; Aged ; Interpersonal Relations ; Activities of Daily Living ; Social Participation ; Social Capital ; Multilevel Analysis ; Cross-Sectional Studies ; Long-Term Care ; Japan/epidemiology* ; Social Support

BACKGROUND: Previous cardiovascular risk prediction models in Japan have utilized prospective cohort studies with concise data. As the health information including health check-up records and administrative claims becomes digitalized and publicly available, application of large datasets based on such real-world data can achieve prediction accuracy and support social implementation of cardiovascular disease risk prediction models in preventive and clinical practice. In this study, classical regression and machine learning methods were explored to develop ischemic heart disease (IHD) and stroke prognostic models using real-world data. METHODS: IQVIA Japan Claims Database was searched to include 691,160 individuals (predominantly corporate employees and their families working in secondary and tertiary industries) with at least one annual health check-up record during the identification period (April 2013-December 2018). The primary outcome of the study was the first recorded IHD or stroke event. Predictors were annual health check-up records at the index year-month, comprising demographic characteristics, laboratory tests, and questionnaire features. Four prediction models (Cox, Elnet-Cox, XGBoost, and Ensemble) were assessed in the present study to develop a cardiovascular disease risk prediction model for Japan. RESULTS: The analysis cohort consisted of 572,971 invididuals. All prediction models showed similarly good performance. The Harrell's C-index was close to 0.9 for all IHD models, and above 0.7 for stroke models. In IHD models, age, sex, high-density lipoprotein, low-density lipoprotein, cholesterol, and systolic blood pressure had higher importance, while in stroke models systolic blood pressure and age had higher importance. CONCLUSION Our study analyzed classical regression and machine learning algorithms to develop cardiovascular disease risk prediction models for IHD and stroke in Japan that can be applied to practical use in a large population with predictive accuracy.
Humans ; Cardiovascular Diseases/epidemiology* ; Prognosis ; Prospective Studies ; Japan/epidemiology* ; Stroke/etiology* ; Myocardial Ischemia/epidemiology* ; Risk Assessment/methods*

During the recent emergence of COVID-19, an increased practice of hand hygiene coincided with the reduced incidence of the norovirus epidemic in Japan, which is similar to experience with the pandemic flu in 2009. We investigated the relationship between the sales of hand hygiene products, including liquid hand soap and alcohol-based hand sanitizer, and the trend of norovirus epidemic. We used national gastroenteritis surveillance data across Japan in 2020 and 2021 and compared the base statistics of incidence of these two years with the average of the previous 10 years (2010-2019). We calculated the correlations (Spearman's Rho) between monthly sales of hand hygiene products and monthly norovirus cases and fitted them to a regression model. In 2020, there was no epidemic, and the incidence peak was the lowest in recent norovirus epidemics. In 2021, the incidence peak was delayed for five weeks to the usual epidemic seasons. Correlation coefficients between monthly sales of liquid hand soap and skin antiseptics and norovirus incidence showed a significantly negative correlation (Spearman's Rho = -0.88 and p = 0.002 for liquid hand soap; Spearman's Rho = -0.81 and p = 0.007 for skin antiseptics). Exponential regression models were fitted between the sales of each hand hygiene product and norovirus cases, respectively. The results suggest hand hygiene using these products is a potentially useful prevention method against norovirus epidemics. Effective ways of hand hygiene for increasing the prevention of norovirus should therefore be studied.
Humans ; Japan/epidemiology* ; COVID-19 ; Hand Hygiene ; Soaps ; Anti-Infective Agents, Local ; Norovirus