Environmental Health and Preventive Medicine最新文献

Background: Medical Aid (MA) beneficiaries, belonging to low-income and vulnerable groups, tend to utilize more healthcare services than patients covered by general health insurance. This study aimed to investigate shifts in medical expenses among South Korean MA beneficiaries from 2010 to 2020 in response to changes in health coverage.

Methods: This study was a retrospective cohort study that involved analyzing data from 354,289 MA beneficiaries aged 20 years and older as of 2010 whose healthcare utilization data could be tracked up to 2020. The impact of changes in health coverage of MA beneficiaries on the increase in medical expenses was analyzed with multiple logistic regression analysis.

Results: The findings revealed that the group maintaining their MA eligibility had a higher rate of increase in medical expenses compared to those transitioning from MA to National Health Insurance (NHI). Even after adjusting for covariates, the likelihood of an increase in total annual medical expenses was more than 1.4 times higher for the MA maintenance group. However, the group that maintained MA also had higher initial healthcare expenses, indicating poorer health status, compared to the group that transitioned to NHI.

Conclusion: In the public healthcare domain, such as MA, it is crucial to enhance access to necessary healthcare services while preventing unnecessary medical treatments. There is a need for systemic improvements to ensure that low-income, medically vulnerable groups can appropriately use the healthcare services they require to achieve high-value health outcomes.

Background: Previous evidence showed that ambient air pollution and cardiovascular mortality are related. However, there is a lack of evidence towards the modification effect of long-term lifestyle on the association between short-term ambient air pollution and death from cardiovascular events.

Method: A total of 14,609 death from major adverse cardiovascular events (MACE) were identified among the China Kadoorie Biobank participants from 2013 to 2018. Ambient air pollution exposure including particulate matter 2.5 (PM_2.5), SO₂, NO₂, CO, and O₃ from the same period were obtained from space-time model reconstructions based on remote sensing data. Case-crossover design and conditional logistic regression was applied to estimate the effect of short-term exposure to air pollutants on MACE mortality.

Results: We found MACE mortality was significantly associated with PM_2.5 (relative percent increase 2.91% per 10 µg/m³ increase, 95% CI 1.32-4.53), NO₂ (5.37% per 10 µg/m³ increase, 95% CI 1.56-9.33), SO₂ (6.82% per 10 µg/m³ increase, 95% CI 2.99-10.80), and CO (2.24% per 0.1 mg/m³ increase, 95% CI 1.02-3.48). Stratified analyses indicated that drinking was associated with elevated risk of MACE mortality with NO₂ and SO₂ exposure; physical inactivity was associated with higher risk of death from MACE when exposed to PM_2.5; and people who had balanced diet had lower risk of MACE mortality when exposed to CO and NO₂.

Conclusions: The study results showed that short-term exposure to ambient PM_2.5, NO₂, SO₂, and CO would aggravate the risk of cardiovascular mortality, yet healthy lifestyle conduct might mitigate such negative impact to some extent.

Background: Japanese people sleep less compared to other countries around the world. Using a large nationally representative survey in 2019 and 2022, we investigated whether sleep duration and nonrestorative sleep (NRS) among Japanese people have improved or worsened due to the COVID-19 pandemic.

Methods: Data were drawn from the Comprehensive Survey of Living Conditions, a nationwide cross-sectional sample based on self-administered questionnaires. We analyzed 426,510 people in 2019 and 375,578 people in 2022 aged ≥20 living in the community. The generalized estimating equations of the multivariable Poisson regression models were used to estimate adjusted prevalence of NRS by survey year. Potential confounders included gender, age, marital status, family size, housing tenure, equivalent household expenditures, education, employment status, illness under treatment, lifestyle behaviors (i.e., smoking, drinking, dietary, and fitness habits), mental health, and sleep duration.

Results: Among the study participants, 35.7% slept less than 6 hours and 20.9% had NRS. Regarding sleep duration, the prevalence of sleep duration of less than 6 hours was significantly lower in 2022 than in 2019 for both men and women. By gender and age, the prevalence of short sleep duration (<6 hours) significantly decreased for both men and women under the age of 49, but increased significantly for men aged ≥50 and women aged ≥75. Regarding NRS, the prevalence of NRS was significantly lower in 2022 than in 2019 regardless of gender and age: Prevalence among men was 21.4% in 2019 and 18.8% in 2022, and prevalence among women was 23.7% in 2019 and 21.2% in 2022. After adjustment for potential confounders, the difference between the 2022 NRS prevalence and the 2019 NRS prevalence was minus 1.64 percent point (pp) (95% confidence interval minus 1.82 pp to minus 1.46 pp, P < 0.001), showing a significant decrease in the 2022 NRS prevalence. A significant improvement of NRS was independent of the prevalence of short sleep duration, age, gender, and employment status.

Conclusions: The prevalence of NRS among the general population in Japan was significantly reduced during the COVID-19 pandemic compared to before the COVID-19 pandemic. We need to monitor whether this decline continues or returns to pre-pandemic levels.

Background: Since the accident at Fukushima Daiichi Nuclear Power Plant (FDNPP), concerns have arisen in Japan regarding the presence of radionuclides in food. Moreover, exposure levels to ⁹⁰Sr and Pu isotopes in adults and those to ¹³⁴Cs+¹³⁷Cs, ⁹⁰Sr, and Pu (where Cs, Sr, and Pu are cesium, strontium, and plutonium, respectively) in children have not been examined. Therefore, this study employed a duplicate portion approach to examine dietary exposure levels of radionuclides in adults and children following the FDNPP accident.

Methods: The study spanned fiscal years 2012-2014 and was conducted in 10 prefectures: Hokkaido, Iwate, Miyagi, Fukushima, Ibaraki, Saitama, Tokyo, Kanagawa, Osaka, and Kochi. The participants provided portions of their meals for two non-consecutive days and completed questionnaires on the meal items. The activity concentrations of ¹³⁴Cs, ¹³⁷Cs, ⁹⁰Sr, and ^239+240Pu, which are targets of standard limits for radionuclides in foods in Japan, were determined according to the Radioactivity Measurement Series. The daily intake was calculated based on the radionuclide activity concentrations in the duplicate portion samples, and the committed effective doses were estimated using dose coefficients for the ingestion of each radionuclide provided by the International Commission on Radiological Protection.

Results: Approximately 80 duplicate samples were obtained in each fiscal year, and 242 samples were collected. The highest summed activity concentration of ¹³⁴Cs and ¹³⁷Cs was 11 Bq/kg, which was recorded in Date City (child) in 2013; this level was approximately one-ninth of the standard limit for general foods (100 Bq/kg). The committed effective dose from annual ingestion of the sample described above was 74 µSv, approximately 14 times lower than the maximum permissible level of 1 mSv/y. Pu was not detected and the ⁹⁰Sr activity concentrations were similar to those before the FDNPP accident.

Conclusions: For the samples examined in the present study, the ¹³⁴Cs, ¹³⁷Cs, ⁹⁰Sr, and ^239+240Pu dietary exposure levels were considerably lower than the regulatory levels and may not pose a health risk.

Background: Although serum carotene may contribute to dementia prevention, there is a lack of longitudinal evidence for early cognitive decline before dementia symptoms. The aim of this study was to examine whether serum carotene levels were associated with annually evaluated cognitive trajectories among the Japanese general population.

Methods: Among 581 baseline participants, 199 individuals (83 males; mean age [min, max], 62.7 [39, 90] years) who underwent cognitive assessments more than twice after baseline were analyzed. "Attention" levels were assessed using one- and three-target Digit Cancellation Tests (D-CAT1 and D-CAT3). "General cognitive ability" was assessed by the short version of Mini-Mental State Examination (SMMSE). Serum carotenes (α-carotene, β-carotene and lycopene) were measured by high-performance liquid chromatography. After the measurements, we calculated total carotene levels by summing up the levels of all measured carotene. Carotene levels were categorized into three groups for analysis (low: 0%-25%, middle: 25%-75%, and high: 75%-100%). A linear mixed model was used to estimate the slope of the D-CAT score trajectory and to compare it between three categories.

Results: Compared with the middle carotene group, decline of attention was faster in the D-CAT1 for low β-carotene (β = -3.48, p = 0.035), lycopene (β = -3.10, p = 0.062), and total carotene (β = -4.75, p = 0.003), but not for α-carotene (β = -2.60, p = 0.111). For the D-CAT3, decline of attention was faster in the group of low lycopene (β = -3.17, p = 0.002) and total carotene (β = -2.17, p = 0.037) compared with the middle carotene group, while no clear association for α-carotene (β = -0.67, p = 0.521) and β-carotene (β = -0.64, p = 0.639). There were no clear associations between serum carotene and the SMMSE score.

Conclusions: These findings suggest low levels of serum lycopene are associated with a decline of attention in the setting of the general population.

This study was to examine the validity of the Japanese version of MemScreen (MemScreen-J), a touchscreen MCI screening test. 20 patients with MCI aged 65-90 years at the Juntendo Tokyo Koto Geriatric Medical Center were recruited as cases in December 2023. Non-cases were recruited from local residents in Toon City, Ehime Prefecture in February 2024 and 40 residents, without a medical history of MCI, aged 58-84 years were included in the present study. MemScreen-J test, a self-administered screening test in the form of a digital application, downloadable on a tablet, was administered to participants to assess their cognitive function. Defining the group at high risk of MCI based on a MemScreen-J test score of 28 or lower achieved the best Youden index in the study sample, with a sensitivity of 0.75 and a specificity of 0.98. MemScreen-J appeared to be a valid screening tool among persons at the prodromal stage of dementia, given reasonably high accuracy in detection of MCI. This innovative neuropsychological test could be the first step in a diagnostic approach to cognitive complaints in a community, identifying persons at the preclinical stage of dementia.

Background: An increased prevalence of cleft lip and/or palate (CL/P), a major congenital anomaly, has been observed in the offspring of women with elevated body mass index (BMI) before pregnancy. Likewise, gestational comorbidities, such as hypertension and diabetes mellitus, also increase the risk of CL/P; however, the risk linked to the coexistence of these conditions in women with higher BMI on birth prevalence of CL/P remains unclear. This study focused on the combined effects of a high BMI before pregnancy and gestational comorbidities on the birth prevalence of CL/P.

Methods: Among 98,373 live births from the Japan Environment and Children's Study (JECS), a nationwide birth cohort, 255 mothers of infants with CL/P (74, 112, and 69 infants born with cleft lip, cleft lip and palate, and isolated cleft palate, respectively) were included in the analyses. The association of CL/P birth prevalence with pre-pregnancy BMI and gestational comorbidities (hypertension and diabetes) was examined using multivariate logistic regression analyses after multiple imputations, with adjustments for several maternal (age at delivery, smoking habits, and alcohol intake) and child-related (sex and prevalence of other congenital diseases) variables, obtained through medical record transcriptions and self-reports on JECS transcription forms.

Results: Higher prevalence rates of overweight, gestational hypertension, and gestational diabetes mellitus were found in mothers of infants with CL/P (16.1%, 6.3%, and 4.7%, respectively) than in the control group (10.4%, 3.1%, and 3.1%, respectively). The odds ratio [95% confidence interval] for childbirth with CL/P was increased in mothers with high BMI before pregnancy (1.58 [1.11-2.24]). Furthermore, gestational hypertension and diabetes coexisting with high BMI additionally increased the odds ratios for childbirth with CL/P (2.91 [1.28-6.61] and 2.12 [0.87-5.19], respectively).

Conclusion: High maternal BMI, particularly when accompanied by gestational hypertension, was significantly associated with an increased prevalence of childbirth with CL/P.

Background: Heated tobacco products (HTPs) are widely used in Japan, following cigarettes, but their health effects remain unclear. HTPs are often considered a less harmful alternative to cigarettes and are commonly used by adults with asthma, even though smoking is one of the most obvious and treatable factors in asthma. We aimed to elucidate the association between HTP use and asthma symptoms in adults with asthma.

Methods: A total of 3,787 individuals with asthma were extracted from the data in the Japan COVID-19 and Society Internet Survey 2023, an ongoing longitudinal internet-based cohort study conducted by a nationwide internet research company in Japan. They were categorized into three groups (never, past, and current smokers) based on cigarette use. The association between HTP use and worsening of asthma symptoms within the previous 2 months in each group was analyzed using univariate and multivariate logistic regression analyses. Both exposure and outcomes were assessed by self-reporting.

Results: Among the participants, 2,470 (65.2%) were never smokers, 845 (22.3%) were past smokers, and 472 (12.5%) were current smokers. Overall, the proportion of HTP users was 429 (11.3%), and worsened asthma symptoms were observed in 400 (10.6%) individuals. The total proportion of HTP users and worsened asthma symptoms was 70 (2.8%) and 259 (10.5%) among never smokers, 180 (21.3%) and 72 (8.5%) among past smokers, and 179 (37.9%) and 69 (14.6%) among current smokers. After adjusting for confounders, the odds ratio (OR) was 3.25 (95% confidence interval [CI] 1.86-5.68, p < 0.001), 1.47 (95% CI 0.93-2.34, p = 0.1), and 2.23 (95% CI 1.46-3.43, p < 0.001) for never, past, and current cigarette smokers with HTP use, respectively, where never smokers without HTP use were set as the standard.

Conclusion: The use of HTPs, not only cigarette smoking, was associated with worsening of asthma symptoms in adults with asthma. Therefore, people need to understand the harmful effects of HTPs on asthma symptoms.

Background: Dental caries is a chronic childhood disease and one of the most prevalent public health problems worldwide. Lead is a heavy metal that is taken up by the teeth and bones. However, the association between lead exposure during pregnancy, when the tooth germs are formed, and the prevalence of dental caries in the primary dentition remains unclear. This study aimed to examine the association between maternal blood lead levels and the prevalence of dental caries in the primary dentition of children.

Methods: This cross-sectional study was conducted as an Adjunct Study to the Japan Environment and Children's Study (JECS), which is an ongoing nationwide birth-cohort study. Among children participating in the JECS at the University of Occupational and Environmental Health Sub-Regional Center, those aged 7-8 years underwent oral examination and questionnaire administration. The dft (i.e., sum of the number of decayed and filled primary teeth) was then determined. The dft numerically expresses the dental caries prevalence in the primary dentition (larger value indicates more prevalent dental caries). Poisson regression analyses with robust standard errors were performed to evaluate the association between maternal blood lead levels during pregnancy, measured using frozen samples, and the dft.

Results: The study included 139 children, of whom 54.7% were girls, and 89.2% were 7 years old. The median maternal blood lead level was 6.1 ng/g (25-75 percentile, 5.0-7.3). The median dft was 0 (25-75 percentile, 0-4). After adjusting for covariates including age, sex, and oral health status and behavior, maternal blood lead levels were significantly associated with increased dft (prevalence ratio, 1.6; 95% confidence interval, 1.3-1.8; per one standard deviation increase in natural log-transformed maternal blood lead levels).

Conclusions: This study found an association between maternal blood lead levels and the prevalence of dental caries in the primary dentition of children aged 7-8 years. Maternal exposure to lead during mid- to late-term pregnancy may affect the caries susceptibility of children after birth.