Environmental Health and Preventive Medicine最新文献

Background: Overweight and obesity lead to a range of noncommunicable diseases (NCDs), such as type 2 diabetes, cardiovascular disease, and stroke. Physical activity (PA) is an important lifestyle behavior for controlling body weight. Dietary inflammatory index (DII), which is associated with systemic inflammatory markers, is used to evaluate the potential of dietary inflammation. This is the first study to investigate the independent and joint associations of PA and DII with the risk of overweight/obesity among US adults.

Methods: Participants and data were obtained from the National Health and Nutrition Examination Survey (NHANES) from 2007-2018, which is designed to examine the health and nutritional status of the non-institutionalized US population by a complex, multi-stage, probability sampling design.

Results: A total of 10723 US adults were selected. Physically active participants had lower overweight/obesity risk (total-time PA: OR = 0.756, 95% CI: 0.669-0.855; leisure-time PA: OR = 0.723, 95% CI: 0.643-0.813; and walk/bicycle-time PA: OR = 0.748, 95% CI: 0.639-0.875); however, those with work-time PA showed no significant association between PA and overweight/obesity. Compared with participants in the lowest DII group (Q1), those in the other three groups had high risks of overweight/obesity (Q2: OR = 1.218, 95% CI: 1.054-1.409; Q3: OR = 1.452, 95% CI: 1.245-1.693; Q4: OR = 1.763, 95% CI: 1.495-2.079). In joint analyses, PA was not eligible for reducing risks of weight/obesity if far more pro-inflammatory diet (Q4 of DII = 2.949-5.502) was taken in (total-time PA: OR = 1.725, 95% CI: 1.420-2.097; leisure-time PA: OR = 1.627, 95% CI: 1.258-2.105; walk/bicycle-time PA: OR = 1.583, 95% CI: 1.074-2.332; and work-time PA: OR = 1.919, 95% CI: 1.493-2.467).

Conclusions: More leisure-time PA and walk/bicycle-time PA are associated with lower risk of overweight/obesity, and higher DII is associated with higher risk of overweight/obesity. In addition, higher DII impacts overweight/obesity substantially: once the DII score reached Q4, there is still risks of overweight/obesity even if PA is performed.

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.

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.

Background: Many previous studies have reported that COVID-19 vaccine effectiveness decreased over time and declined with newly emerging variants. However, there are few such studies in Japan. Using data from a community-based retrospective study, we aimed to assess the association between vaccination status and severe COVID-19 outcomes caused by the Omicron variant, considering the length of time since the last vaccination dose.

Methods: We included all persons aged ≥12 diagnosed with COVID-19 by a doctor and notified to the Chuwa Public Health Center of Nara Prefectural Government during the Omicron BA.1/BA.2 and BA.5-predominant periods in Japan (January 1 to September 25, 2022). The outcome variable was severe health consequences (SHC) (i.e., COVID-19-related hospitalization or death). The explanatory variable was vaccination status of the individuals (i.e., the number of vaccinations and length of time since last dose). Covariates included gender, age, risk factors for aggravation, and the number of hospital beds per population. Using the generalized estimating equations of the multivariable Poisson regression models, we estimated the cumulative incidence ratio (CIR) and 95% confidence interval (CI) for SHC, with stratified analyses by period (BA.1/BA.2 or BA.5) and age (65 and older or 12-64 years).

Results: Of the 69,827 participants, 2,224 (3.2%) had SHC, 12,154 (17.4%) were unvaccinated, and 29,032 (41.6%) received ≥3 vaccine doses. Regardless of period or age, there was a significant dose-response relationship in which adjusted CIR for SHC decreased with an increased number of vaccinations and a longer time since the last vaccination. On the one hand, in the BA.5 period, those with ≥175 days after the third dose had no significant difference in people aged 65 and older (CIR 0.77; 95% CI, 0.53-1.12), but significantly lower CIR for SHC in people aged 12-64 (CIR 0.47; 95% CI, 0.26-0.84), compared with those with ≥14 days after the second dose.

Conclusion: A higher number of vaccinations were associated with lower risk of SHC against both BA.1/BA.2 and BA.5 sublineages. Our findings suggest that increasing the number of doses of COVID-19 vaccine can prevent severe COVID-19 outcomes, and that a biannual vaccination is recommended for older people.

Background: Dengue fever is a viral infection transmitted to humans through the bite of a mosquito infected with the dengue virus. Dengue is one of the most common infectious diseases in the world, and its incidence is rapidly increasing. We estimated the risk of dengue importation from endemic countries to Japan and the transmission risk within Japan using data collected between 2016 and 2018.

Methods: We conducted simulations that included the number of reported dengue infections and travelers per month in ten countries in Southeast and South Asia.

Results: The estimated importation risks for Japanese returnees and international travelers from each of the ten endemic countries was approximately 1.0 every month from 2016 to 2018. The autochthonous transmission risk in Japan from any target country was 1.0 from June to September yearly. The estimated number of Japanese dengue cases returning to Japan is approximately 25 times higher than that of imported cases reported in Japan.

Conclusions: The risk of dengue importation into Japan can be sufficiently high. Attention should be paid to autochthonous transmission spread between June and September when mosquitoes are active in Japan. Estimates of seasonal risk variation from each dengue virus-endemic country can be used to inform preventive and control measures for dengue in Japan.

Background: Congenital heart disease (CHD) is one of the most common congenital malformations in humans. Inconsistent results emerged in the existed studies on associations between air pollution and congenital heart disease. The purpose of this study was to evaluate the association of gestational exposure to air pollutants with congenital heart disease, and to explore the critical exposure windows for congenital heart disease.

Methods: The nested case-control study collected birth records and the following health data in Tianjin Women and Children's Health Center, China. All of the cases of congenital heart disease from 2013 to 2015 were selected matching five healthy controls for each case. Inverse distance weighting was used to estimate individual exposure based on daily air pollution data. Furthermore, the conditional logistic regression with distributed lag non-linear model was performed to identify the association between gestational exposure to air pollution and congenital heart disease.

Results: A total of 8,748 mother-infant pairs were entered into the analysis, of which 1,458 infants suffered from congenital heart disease. For each 10 µg/m³ increase of gestational exposure to PM_2.5, the ORs (95% confidence interval, 95%CI) ranged from 1.008 (1.001-1.016) to 1.013 (1.001-1.024) during the 1^st-2^nd gestation weeks. Similar weak but increased risks of congenital heart disease were associated with O₃ exposure during the 1^st week and SO₂ exposure during 6^th-7^th weeks in the first trimester, while no significant findings for other air pollutants.

Conclusions: This study highlighted that gestational exposure to PM_2.5, O₃, and SO₂ had lag effects on congenital heart disease. Our results support potential benefits for pregnancy women to the mitigation of air pollution exposure in the early stage, especially when a critical exposure time window of air pollutants may precede heart development.

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.

Background: In the Great East Japan Earthquake of 11 March 2011, an earthquake and accompanying tsunami struck the Tohoku region of northeastern Japan. Buildings collapsed and the tsunami spread waste, including hazardous materials. This study aimed to determine the concentrations of persistent organic pollutants (POPs) in the breast milk of mothers living in the disaster-affected area of Sendai 1 year after the earthquake. Temporal trends in the POPs concentrations were evaluated by comparison with previous studies.

Methods: One hundred breast milk samples were obtained from lactating mothers at a hospital in Sendai in 2012. The results were compared with those from other years to examine whether there were changes in the POPs concentrations after the earthquake. We measured polychlorinated biphenyls (PCBs) and organochlorine pesticides, such as chlordanes, using gas chromatography-mass spectrometer (GC-MS) with negative chemical ionization, and dichlorodiphenyl trichloroethane (DDT) and its metabolites using GC-MS with electron impact ionization.

Results: The mean total PCBs (11 congeners), total chlordane, and total DDT concentrations were 76.2 ng/g lipid, 39.8 ng/g lipid, and 73.5 ng/g lipid, respectively. For the samples collected in 2012, the concentrations of POPs in breast milk showed minimal changes compared with results from previous years for samples collected at the same hospital in Sendai.

Conclusions: Our study demonstrates that 1 year after the earthquake and tsunami, the concentrations of chlorinated POPs in breast milk had not changed substantially.

Background: This study aimed to examine population-based characteristics of non-fatal self-harm in an urban area during pre- and peri-pandemic periods of COVID-19 by sex, age, and severity of self-harm, using pre-hospital medical emergency records.

Methods: We used a registry of all pre-hospital medical records of self-harm cases that occurred in Kawasaki City, Japan, between January 2018 and December 2021. Adjusted incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated using Poisson regression models with the log-transformed population by year, sex, age group, and ward as an offset term.

Results: During the 4-year study period, 1,534 patients were transported by ambulance due to non-fatal self-harm and were alive on arrival at the hospital. Among women, the number of non-fatal self-harm cases increased by 1.2-fold in 2021 compared with that in 2018. The incidence rate of "severe" non-fatal self-harm among men aged 19 years or younger in 2021 (IRR 4.82, 95% CI 1.25-18.65) and that among women aged 50-59 years in 2020 (IRR 2.51, 95% CI 1.06-5.95) significantly increased compared with that 2018 and 2019. The incidence rate of "mild" self-harm among women aged 20-29 years tended to be higher in 2021 than in 2018 and 2019 (IRR 1.42, 95% CI 0.95-2.12, P = 0.085).

Conclusions: During the peri-pandemic period of COVID-19, the incidence rate of "severe" non-fatal self-harm among men aged 19 years or younger and women aged 50-59 years, as well as that of "mild" self-harm among women aged 20-29 years, sharply increased compared with that during the pre-pandemic period. Our findings suggest that in urban areas during public health crises such as a pandemic, it is important to take measures to reduce the risk of non-fatal self-harm in young women, in addition to strengthening counseling and support for young women at risk for completed suicide.