Environmental Health and Preventive Medicine最新文献

Background: SARS-CoV-2 (COVID-19) is transmitted via infectious respiratory particles. Infectious respiratory particles are released when an infected person breathes, coughs, or speaks. Several studies have measured respiratory particle concentrations through focusing on activities such as breathing, coughing, and short speech. However, few studies have investigated the effect of speech duration.

Methods: This study aimed to clarify the effects of speech duration and volume on the respiratory particle concentration. Study participants were requested to speak at three voice volumes across five speech durations, generating 15 speech patterns. Participants spoke inside a clean booth where particle concentrations and voice volumes were measured and analyzed during speech.

Results: Our findings suggest that as speech duration increased, the aerosol number concentration also increased. Through focusing on individual differences, we considered there might be super-emitters who emit more aerosol particles than the average human. Two participants were identified as statistical outliers (aerosol number concentration, n = 1; mass concentration, n = 1).

Conclusions: Considering speech duration may improve our understanding of respiratory particle concentration dynamics. Two participants were identified as potential super-emitters.

Background: A comprehensive understanding of the epidemiology of pediatric out-of-hospital cardiac arrest (OHCA) occurring under school supervision is lacking. We aimed to comprehensively describe the characteristics and outcomes of OHCA among students in elementary schools, junior high schools, high schools, and technical colleges in Japan.

Methods: OHCA data from 2008-2021 were obtained from the SPIRITS study, which provides a nationwide database of OHCAs occurring under school supervision across Japan. We included cases in which resuscitation was attempted by emergency medical service personnel or bystanders. The cases were classified into three groups based on their etiology: cardiac, non-cardiac, and traumatic origin. The primary outcome was one-month survival with favorable neurological outcomes, defined as a Glasgow-Pittsburgh cerebral performance category of 1 or 2. The demographic characteristics, event details, and outcomes were compared across the three groups by using χ² tests for categorical variables and one-way analyses of variance for continuous variables.

Results: During the 14-year study period, 602 OHCA cases were confirmed, with 430 (71.4%) classified as cardiac, 91 (15.1%) as non-cardiac, and 81 (13.5%) as traumatic origin. Non-cardiac and traumatic cases were less likely to be witnessed at the time of arrest (46.2% and 42.0%, respectively) than cardiac cases (82.6%; p < 0.001). Initiation of cardiopulmonary resuscitation by bystanders was less common in non-cardiac and traumatic cases (62.6% and 42.0%, respectively) than that in cardiac cases (82.8%; p < 0.001). The delivery of defibrillation using public-access automated external defibrillators was also significantly less frequent in non-cardiac (3.3%) and traumatic cases (6.2%) than that in cardiac cases (59.8%; p < 0.001). Ventricular fibrillation (VF) as the first documented rhythm was observed in 77.9% of cardiac cases but was much less common in non-cardiac (5.5%) and traumatic cases (8.6%; p < 0.001). One-month survival with favorable neurological outcomes was significantly lower in non-cardiac (6.6%) and traumatic cases (0%) than that in cardiac cases (50.2%; p < 0.001).

Conclusions: OHCAs of cardiac origin were more frequently associated with VF and had relatively good prognoses. In contrast, OHCAs of non-cardiac and traumatic origins consistently resulted in poor outcomes, highlighting the critical importance of prevention strategies to reduce the occurrence of these incidents.

Background: High levels of attention-deficit/hyperactivity disorder (ADHD) traits are associated with various outcomes, including depressive symptoms, functional impairment, and low self-esteem. Additionally, individuals with high levels of ADHD traits are reported to be more adversely affected by fear of coronavirus disease 2019 (COVID-19). The current study aimed to examine whether the association between ADHD traits and outcomes was partially mediated by fear of COVID-19 using mediation analysis.

Methods: A cross-sectional study was conducted in a sample of university students in medical-related faculties (n = 1,166). ADHD traits, fear of COVID-19, depressive symptoms, functional impairment, and self-esteem were assessed using the adult ADHD Self-Report Scale, Fear of COVID-19 Scale, K6 Scale, Sheehan Disability Scale, and Rosenberg Self-Esteem Scale, respectively. We used linear regression analysis and the Paramed command in Stata to analyze whether fear of COVID-19 mediated the association between ADHD traits and outcomes.

Results: ADHD traits were significantly associated with outcomes. Regarding the impact of fear of COVID-19, the results revealed a significant association between ADHD traits and fear of COVID-19, and between fear of COVID-19 and outcomes. The results of the mediation analyses showed that the association between ADHD traits and outcomes was partially mediated by the fear of COVID-19 (depressive symptoms: direct effect B = 1.029, 95% confidence interval [CI] 0.878, 1.181, indirect effect B = 0.021, 95% CI 0.002, 0.040; functional impairment: direct effect B = 0.786, 95% CI 0.593, 0.979, indirect effect B = 0.033, 95% CI 0.005, 0.060; self-esteem: direct effect B = -1.052, 95% CI -1.226, -0.878, indirect effect B = -0.024, 95% CI -0.046, -0.002).

Conclusions: Developing preventive measures against the adverse impacts of pandemics like COVID-19 will be particularly important for individuals with high levels of ADHD traits in future.

Background: Heavy metals are significant risk factors for kidney function. Numerous studies have shown that exposure to heavy metals negatively correlates with kidney function through oxidative stress pathways, and serum α-klotho is linked to oxidative stress. However, the role of α-klotho in the relationship between blood lead, mercury, and kidney function remains unclear.

Method: This study evaluated the mediating role of alpha-klotho in the relationship between lead, mercury and renal function, using data from the 2007-2016 National Health and Nutrition Examination Survey (NHANES) in U.S. adults aged 40-79. The sample included 11,032 participants, with blood lead, mercury, α-klotho, and other relevant covariates measured. Inductively coupled plasma mass spectrometry was used to assess blood lead and mercury levels, and enzyme-linked immunosorbent assay (ELISA) was employed to measure serum α-klotho. Kidney function was evaluated using estimated glomerular filtration rate (eGFR) based on creatinine levels. Multivariable linear regression was conducted to analyze the relationships between blood lead, mercury, α-klotho, and eGFR. A mediation analysis model was used to assess whether α-klotho influenced these associations.

Results: We observed a significant association between blood lead and eGFR. Mediation analysis revealed that α-klotho accounted for 12.76% of the relationship between serum lead and eGFR in the NHANES population. Subgroup analysis showed that α-klotho mediated 12.43%, 6.87%, 21.50% and 5.44% of the relationship between blood lead and eGFR in women, middle-aged adults (40-59 years old), without cardiovascular disease and hypertension, respectively. However, α-klotho did not mediate the relationship between blood mercury and eGFR in terms of gender or age. This newly identified pathway may provide valuable insights for the prevention and treatment mechanisms related to kidney function impairment.

Conclusion: We found that blood lead was associated with renal function. According to the results of subgroup analysis, for blood lead, serum α-klotho mediated the association in females, middle aged 60-79 years. The relationship between blood mercury and renal function was not clinically significant, and serum α-Klotho mediated the relationship between blood mercury and renal function without significant clinical significance.

Background: Owing to shortage of surgical and N95 filtering facepiece respirators (FFRs) during the COVID-2019 pandemic, various masks were developed to prevent infection. This study aimed to examine the inward leakage rate (ILR) of sealed face masks and modified surgical masks using a quantitative fit test and compared it with the ILR of unmodified N95 FFRs.

Methods: We conducted paired comparisons of ILRs of bent nose-fit wire masks, double masks, and N95 FFRs from October to December 2021. To measure the protective effectiveness of masks, participants wore masks, and the number of particles outside and inside the mask were measured. The ILR was based on the percentage of particles entering the mask using a fit tester.

Results: We enrolled 54 participants (20 men and 34 women) in this study. The median ILR for surgical masks without and with a W-shaped bend in the nose-fit wire were 96.44% and 50.82%, respectively. The nose-fit wire adjustment reduced the ILR of surgical masks by a mean of 28.57%, which was significantly lower than the ILR without adjustment (P < 0.001). For double masks, with surgical or polyurethane masks on top of the W-shaped mask, the ILR did not differ significantly from that of N95. Although the filtration performance of double surgical masks matched that of N95 masks, their ILR was notably higher, indicating that double masks do not provide equivalent protection.

Conclusions: Wearing N95 masks alone is effective in many cases. However, surgical mask modifications do not guarantee consistent effectiveness. Properly selected, sealed masks with a good fit overcome leakage, emphasizing their crucial role. Without evidence, mask-wearing may lead to unexpected infections. Education based on quantitative data is crucial for preventing adverse outcomes.

Background: Chronic noise exposure poses a remarkable public health concern, drawing attention to its impacts on the brain. Ferroptosis is involved in several brain-related diseases. However, the role of ferroptosis in the effects of chronic noise on the brain remains elusive. This study aimed to investigate the effects of chronic noise exposure on the brain and elucidate the underlying mechanisms.

Methods: A chronic noise-induced cognitive impairment model in rats was constructed and validated. The pathological state and ferroptosis level of the rat hippocampus were determined using Western blotting and immunohistochemistry. Bioinformatics was employed to investigate the interrelationship between chronic noise exposure and genes. Genetic relationships were analyzed using Mendelian randomization (MR) analysis. Cytoscape was employed for the prediction of upstream molecular and drug targets.

Results: In vivo experiments revealed that chronic noise exposure could induce Alzheimer's disease (AD)-like neuropathological changes in rat hippocampus and cognitive impairment. Moreover, protein markers indicative of ferroptosis and levels of lipid peroxidation were quantified to elucidate underlying mechanisms. Thereafter, oxidative stress- and ferroptosis-related differentially expressed genes (DEGs) underwent functional enrichment and PPI network analyses. Additionally, 8 genes with diagnostic significance were identified. In MR analysis, retinoic acid receptor responder 2 (Rarres2) gene exhibited a negative genetic relationship with AD.

Conclusions: Chronic noise exposure could induce AD-like neuropathological changes and cognitive impairment via ferroptosis. The results of MR analysis indicated that Rarres2 gene may act as a protective factor in AD. This gene may be upstream of ferroptosis and serve as a target for the prevention and treatment of chronic noise-induced cognitive impairment.

Background: The association between alcohol consumption and atherosclerotic cardiovascular disease (ASCVD) was controversial, and no previous studies have shown the impact of dyslipidemia on the association. We aimed to clarify the association between alcohol consumption and death from cardiovascular disease (CVD) and its subtypes and the impact of dyslipidemia on the association.

Methods: We conducted a 20-year cohort study to clarify the association between alcohol intake and death from CVD and its subtypes in 2,909 Japanese men. We estimated the hazard ratio (HR) and 95% confidence intervals (CIs) for current drinkers with non-drinkers as the reference, after adjusting for potential confounders using Cox proportional hazards models. We also investigated the association between alcohol consumption and ASCVD or CVD death stratified by the presence or absence of dyslipidemia.

Results: During 50,782 person-years of follow-up period, 223 participants died from total CVD, 110 participants died from ASCVD, and 25 participants died from cerebral hemorrhage. Current drinkers with 1 gou/day were significantly associated with lower risk of ASCVD (HR: 0.60, 95%CI: 0.37-0.98), which is more apparent in those without dyslipidemia, and current drinkers with ≥3 gou/day were significantly associated with higher risk of cerebral hemorrhage (HR: 4.13, 95%CI: 1.12-15.19).

Conclusions: Small amounts of alcohol drinking were associated with lower risk of ASCVD in Japanese men, especially those without dyslipidemia. Meanwhile, excessive alcohol drinking was associated with higher risk of cerebral hemorrhage. Our findings suggest that it is important for current Japanese drinkers to reduce alcohol consumption for preventing ASCVD or cerebral hemorrhage.

Background: Per- and polyfluoroalkyl substances (PFAS) are now considered global contaminants posing health risks. Recent human biomonitoring data in Japan are presented.

Methods: Human biomonitoring data from Japan, dating back to 2000, were reviewed. In addition, 399 serum samples collected in a primary care clinic in Urayasu City, Okinawa Island-one of the highest PFAS-exposed areas in Japan-between 2021 and 2022 were analyzed. Serum levels of four PFAS were compared with risk levels based on the assessment by Sonne et al. and the European Food Safety Agency.

Results: The PFAS levels in the general population from various areas other than Hokkaido (16.1-43.5 ng/mL) are classified at moderate to severe risk for immunotoxicity based on the assessment.

Conclusions: A portion of the Japanese population has had high exposure to PFAS and was at high risk of immunotoxicity, and this situation remained in PFAS-contaminated areas in the 2020s.

Background: Cadmium, a toxic metal, is widely encountered in diverse environmental contexts. Despite its pervasive exposure, there is limited research on the association between blood cadmium levels and depression, especially among females. This study aimed to investigate the relationship between blood cadmium levels and depression in adult women.

Methods: Data spanning 2005-2016 from the National Health and Nutrition Examination Survey (NHANES) were selected. Depression was diagnosed with the Patient Health Questionnaire (PHQ-9, score ≥10). Multiple logistic regression, multiple linear regression, and smoothed curve fitting were used to investigate the relationship between blood cadmium and depression. Subgroup analyses and interaction tests were performed to evaluate the stability of this association across populations.

Results: A total of 1,173 individuals were diagnosed with depression. The heightened prevalence of depression was linked to increased blood cadmium levels, a trend that persisted even after quartering blood cadmium. In the fully adjusted model, each incremental unit of blood cadmium was associated with a 33% rise in the prevalence of depression (OR = 1.33, 95% CI: 1.21-1.45). Participants in the highest quartile were 63% more likely to experience depression compared to those in the lowest quartile of blood cadmium (OR = 1.63, 95% CI: 1.15-2.30), and PHQ-9 score increased by 0.73 (β = 0.73, 95% CI: 0.30-1.17). This positive association may be relevant to the general population.

Conclusions: Blood cadmium levels are associated with depression in adult women, and this association varies by age and smoking status.

One consequence of population aging is an increase in the number of older wheelchair users. They often board the motor vehicle from the rear for moving. Recently, wheelchair user vehicle passengers have involved in motor vehicle collisions and died. A three-point seatbelt does not adequately fit most wheelchair user passengers because of the way that the wheelchair is constructed. Therefore, owing to the movement of the body immediately after the collision, the wheelchair user passengers attacked their body to the interior of the vehicle or suffered from the intrusion of the lap belt into the abdomen, subsequently suffered from severe head, chest or abdominal injuries. According to the review of all fatal motor vehicle collisions in Shiga Prefecture, Japan, which has a population of approximately 1.4 million, from 2017 to 2022, the rate of wheelchair users in fatal motor vehicle passenger increased from 3.6% in 2017 to 2019 to 7.8% in 2020 to 2022. Therefore, there is a risk that substantial numbers of wheelchair user passengers involved in motor vehicle collisions will die. However, in Japan, there are no official statistics on the involvement of wheelchair user passengers in motor vehicle collisions. Therefore, we propose a nationwide registration of injuries and fatalities in wheelchair user passengers. Investigating the mechanisms of injury in wheelchair user passengers would contribute to the development of safety measures, especially for restraint systems. Established preventive measure would contribute to the decrease of fatally or severely injured motor vehicle collision passengers.