Prenatal and postnatal exposure to PM2 .5 and the risk of tic disorders.

BACKGROUND: Tic disorders are common neurodevelopmental disorders during childhood. Whether prenatal and postnatal exposure to particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5 ) plays a role in the development of tic disorders remains unexplored. OBJECTIVES: To investigate the association of exposure between PM2.5 during the pregnancy and infancy periods and the risk of tic disorders. METHODS: This birth cohort study recruited singleton live births at term gestations in central Taiwan from the Taiwan Maternal and Child Health Database between 2004 and 2012 and followed up to the end of 2017. New cases of tic disorders were defined using the ICD-9-CM (307.2) and ICD-10-CM (F95), which include all tic spectrum disorders. We assigned daily PM2.5 concentrations derived from a satellite-based model to individuals based on maternal residential addresses at delivery. We fit Cox proportional hazard model and distributed lag non-linear model to estimate the associations between PM2.5 and tic disorders, with hazard ratio (HR) with 95% confidence interval (CI) as the effect measure. RESULTS: Of the 309,376 singleton live births at term gestations, we identified 5902 (1.9%) tic disorder cases. The HR of tic disorders was positively associated with a 10 µg/m3 increase in PM2.5 : during pregnancy HR 1.09, 95% CI 1.04, 1.15 and during infancy HR 1.12, 95% CI 1.06, 1.18. The vulnerable time window for infants with increased risk of tic disorders was 6-52 weeks after birth. We observed a nonlinear relationship between PM2.5 and the risk of tic disorders, with exposure to PM2.5 between 16 and 64 µg/m3 being associated with the risk of tic disorders. The association was restricted to Tourette's disorder group. Infant sex did not modify these associations. CONCLUSIONS: Infants delivered at term and exposed to PM2.5 are associated with an increased risk of tic disorders (6-52 weeks). Further studies are needed to confirm these associations.

Maternal exposure to fine particulate matter and congenital heart defects during preconception and pregnancy period: A cohort-based case-control study in the Taiwan maternal and child health database.

BACKGROUND: Few studies have explored the association between maternal exposure to particulate matter with an aerodynamic diameter of ≤2.5 µm (PM2.5) and congenital heart defects occurring before and during pregnancy. We aimed to investigate the association and the critical time windows between the maternal exposure to PM2.5 and congenital heart defects. METHOD: We conducted a cohort-based case-control study of 507,960 participants obtained from the Taiwan Maternal and Child Health Database between 2004 and 2015. We applied satellite-based spatiotemporal models with 1-km resolution to calculate the average PM2.5 concentration during preconception and the specific periods of pregnancy. We also performed conditional logistic regression with distributed lag non-linear models (DLNMs) to assess the effects of weekly average PM2.5 on both congenital heart defects and their isolated subtypes, as well as the concentration-response relationships. RESULTS: In DLNMs, exposure to PM2.5 (per 10 µg/m3) during weeks 7-12 before conception and weeks 3-9 after conception was associated with congenital heart defects. The strongest association at 12 weeks before conception (odds ratio [OR] = 1.026, 95% confidence intervals [CI]: 1.012-1.040) and 7 weeks after conception (OR = 1.024, 95% CI: 1.012-1.036) for every 10 µg/m3 increase in PM2.5 concentration. In modification analysis, strongest associations were observed for low SES. CONCLUSIONS: Our study revealed that exposure to ambient PM2.5 raises the risk of congenital heart defects, particularly among individuals with lower socioeconomic status. Moreover, our findings suggest that preconception exposure to PM2.5 may be a crucial period for the development of congenital heart defects.

Prenatal and postnatal exposure to heavy metals in PM2.5 and autism spectrum disorder.

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders, and its incidence is increasing over time. Although several environmental factors have been suspected to be risk factors for ASD, studies on the effects of airborne heavy metals on newly developed ASD are still limited. We conducted a large birth cohort study of 168,062 live term births in Taichung during 2004-2011 to assess the association of heavy metals in particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5) with ASD, and identify sensitive time windows during prenatal and postnatal periods. Heavy metals, including arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in PM2.5, were estimated using the Weather Research and Forecasting/Chem (WRF/Chem), inserted from the top 75 emission sources for the module. The association between childhood ASD and 4 metals were analyzed from pregnancy to 9 months after birth. The Cox proportional hazard model with a distributed lag nonlinear model (DLNM) was used to estimate the association between heavy metals in PM2.5 and ASD. We identified 666 incident ASD cases in 168,062 participants. A positive association between Hg and ASD was found at 9 months after birth (Hazard Ratio: 1.63; 95% CI: 1.13-2.36). According to the DLNM, there was an increased risk of exposure to Hg during 10-25 weeks after birth, and decreased risk of exposure to Hg during gestational weeks 4-6. Exposure to As and Hg on the risk of ASD were significantly stronger in low birth weight infants (<2500 g) than in those of birth weight ≥2500 g during postnatal period. Postnatal exposure to Hg in PM2.5 may associate with increased ASD incidence. Infants with low birth weight and exposure to As and Hg in PM2.5 are more likely to develop ASD.

PM2.5 exposure and incident attention-deficit/hyperactivity disorder during the prenatal and postnatal periods: A birth cohort study.

Only a few studies have assessed the effects of fine particulate matter (PM2.5) exposure during the prenatal and postnatal periods on the development of attention-deficit/hyperactivity disorder (ADHD). We investigated the association of exposure to PM2.5 during pregnancy and early life with ADHD. This birth cohort consisted of 425,736 singleton live-term births between 2004 and 2015 in Taiwan. Daily PM2.5 concentrations were derived from a 1-km satellite-based estimation model. A time-dependent Cox model was used to assess the effects of PM2.5 on ADHD during the first, second, and third trimesters and from age 1-5 years after birth. The distributed lag nonlinear model was utilized to explore the dose-response relationship. Total 9,294 children were diagnosed with ADHD during the study period. The hazard ratio (HR) of ADHD was significantly associated with a 10 µg/m3 increase in PM2.5 during the first trimester (HR = 1.26; 95% confidence interval [CI]: 1.13-1.40) and increased at PM2.5 over 16 µg/m3. For postnatal periods, the HR of ADHD was significantly associated with increased PM2.5 at the first to third year of life (HR ranged between 1.40 and 1.87). According to the dose-response relationship of exposure to PM2.5 at the third year of life, the HR of ADHD was significantly associated with PM2.5 above 16 µg/m3 and sharply increased as PM2.5 >50 µg/m3. We did not observe a significant modification of sex on the relation between PM2.5 and ADHD. Exposure of pregnant women to PM2.5 above 16 µg/m3 from conception to the early life of their children may increase the risk of ADHD. The government should improve the criteria for air quality control and meet the WHO air quality guidelines to protect pregnant women and children from developing ADHD in the future.

Combined exposure to heavy metals in PM2.5 and pediatric asthma.

BACKGROUND: Asthma is the most common chronic allergic disease in children; it affects more than 300 million people worldwide. Information on the association between exposure to ambient heavy metals and incidence of pediatric asthma is limited. OBJECTIVE: We sought to evaluate the effects of heavy metals during pregnancy and infancy periods with asthma and identify a sensitive time window, clarifying the effect of ambient heavy metals on lung development. METHODS: A total of 171,281 children, who were born from 2004 to 2011 in Taichung City, were followed until 2014. Concentrations of ambient heavy metals such as arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) were obtained from the Weather Research and Forecasting/Chem model, considering the top 75 emission sources in Taiwan. The distributed lag nonlinear model was used to investigate the relationship between combined exposure to heavy metals in 2.5 µm particulate matter and asthma in pregnant women and 1-year-old infants. RESULTS: We identified 31,277 new asthma cases from the birth cohort. After adjustment for socioeconomic status, maternal age, maternal atopy, maternal anemia, and maternal kidney disease, distributed lag nonlinear model results revealed positive associations of asthma with exposure to Pb during gestational weeks 1 to 14 and 21 to 40, and 1 to 3 weeks after birth. Regarding the sensitivity analyses, coexposure to Pb and As, coexposure to Pb and Cd, and coexposure to Pb and Hg were positively associated with asthma onset as well. CONCLUSIONS: Our study suggested that combined exposure to Pb with As, Cd, and Hg during early and late gestational weeks was associated with the incidence of pediatric asthma.

Effect of exposure to fine particulate matter during pregnancy and infancy on paediatric allergic rhinitis.

BACKGROUND: The effect of prenatal and postnatal exposure to fine particulate matter (PM2.5) on the development of allergic rhinitis (AR) is poorly understood. We further identified the vulnerable period for AR development to determine methods to decrease adverse effects. METHODS: We used a large population-based birth cohort of 140 911 singleton live infants in Taichung, Taiwan with a highly temporal-resolution satellite-based hybrid model to evaluate the effects of prenatal and early postnatal exposure on the onset of AR. RESULTS: Among 140 911 children, 47 276 (33.55%) were cases of incident AR. The mean age of the children with AR at initial diagnosis was 2.97±1.78 years. We identified a significant association of AR with an interquartile range (IQR 17.98 µg/m3) increase in PM2.5 from 30 gestational weeks to 52 weeks after birth. The exposure-response relationship revealed that AR had a significant positive association between PM2.5 of 26-76 µg/m3 (adjusted hazard ratios ranged from 1.00 to 1.05). CONCLUSION: Our study provides evidence that both prenatal and postnatal exposures to PM2.5 are associated with later development of AR. The vulnerable time window may be within late gestation and the first year of life. Further study is required to confirm the vulnerable time period of PM2.5 on AR.

Long-term exposure to fine particulate matter and osteoporotic fracture: A case-control study in Taiwan.

Few studies have explored the relationship between long-term exposure to particulate matter with an aerodynamic diameter of ≤2.5 µm (PM2.5) and osteoporotic fracture, particularly in high PM2.5 level areas. The aim of this study was to assess the association between long-term exposure to PM2.5 and osteoporotic fracture. We performed a matched case-control study of 16,175 participants obtained from a hospital registry during 2005-2014 in Taiwan. A major osteoporotic fracture was defined as a fracture of the spine, hip, proximal humerus, and forearm. We applied satellite-based spatiotemporal models with 1-km resolution to individually calculate the 1-year average PM2.5 concentration before the index date which was defined as the first visit date for the osteoporotic fracture. Logistic regression models with and without potential confounding factors were used to estimate odds ratios (OR) and 95% confidence intervals (CI) between PM2.5 and osteoporotic fracture, whereas a restricted cubic spline model was used to estimate the dose-response relationship. The sample's median age was 44.7 years (interquartile range: 30.7, 63.1 years). We observed that long-term PM2.5 exposure was associated with osteoporotic fracture, the OR was 1.12 (95% CI: 1.03, 1.22) per 10-µg/m3 increase in PM2.5 in women. In the dose-response association, the OR of osteoporotic fracture was significantly increased for PM2.5 exposures more than 41 µg/m3. We did not find a significant association between PM2.5 (per 10-µg/m3 increase) and osteoporotic fracture among overall population (adjusted OR, 1.02 [95% CI, 0.97 to 1.08]) and men (adjusted OR, 0.94 [95% CI, 0.86 to 1.02]). The results of the stratified analysis showed that women were more sensitive to the adverse impact of PM2.5 that were men, and evidence was obtained of sex-based effect modification (P for interaction = 0.002). Our findings suggest that long-term exposure to PM2.5 is associated with osteoporotic fracture, particularly among women.

Association between cirrhosis and herpes zoster in a cohort study in Taiwan.

OBJECTIVES: The aim of the study was to assess if an association exists between cirrhosis and herpes zoster in Taiwan. METHODS: A retrospective cohort study was designed to analyse the 2000-2013 claim dataset of 1 million insured residents who were randomly sampled from the Taiwan National Health Insurance Program. In total, 16 190 subjects aged 20-84 years old with newly diagnosed cirrhosis since 2000 to 2012 were identified as the cirrhosis group and 16 190 sex- and age-matched subjects without cirrhosis were selected as the non-cirrhosis group. Both cirrhosis and non-cirrhosis groups were followed until a new diagnosis of herpes zoster was made or until the end of 2013. The multivariable Cox proportional hazard regression model was applied to calculate the hazard ratio (HR) and 95% confidence interval (CI) for herpes zoster associated with cirrhosis. RESULTS: The incidence rate of herpes zoster was 1.08-fold greater in the cirrhosis group than the non-cirrhosis group (8.33 vs 7.69 per 1000 person-years, 95%CI 1.02-1.15). After adjusting for confounders, the adjusted HR of herpes zoster was 1.11 (95% CI 1.004-1.24) for the cirrhosis group compared with the non-cirrhosis group. The adjusted HR increased to 1.33 (95% CI 1.02-1.74) for the decompensated cirrhosis group compared with the non-cirrhosis group. CONCLUSIONS: Cirrhosis is associated with a small but significant increase in the risk of herpes zoster. Given that the risk of herpes zoster is small and the expense of herpes zoster vaccination is high, whether cirrhotic persons need to be vaccinated should assess the balance of cost and benefit.

The impacts of ambient temperature and ultraviolet radiation on the incidence of herpes zoster: An ecological study in Taiwan.

The aim of the study was to examine the relationship between ambient temperature, ultraviolet radiation, and the development of herpes zoster in Taiwan. An ecological study was conducted to analyse the database of the Taiwan National Health Insurance Programme. Participants aged ≥20 years with newly diagnosed herpes zoster between 2003 and 2012 were selected for analysis. The monthly incidence rate of herpes zoster was measured between 2003 and 2012. Monthly average ambient temperature in Celsius (°C) between 2003 and 2012 was measured according to the official database of the Central Weather Bureau in Taiwan. Monthly accumulated ultraviolet radiation (MJ m-2 ) between 2003 and 2012 was measured according to the official database of the Environmental Protection Administration in Taiwan. The overall incidence rates of herpes zoster ranged from 2.54 to 5.67 per 10 000 persons per month from 2003 to 2012.The monthly average ambient temperature was higher and the monthly accumulated ultraviolet radiation was stronger from May to October. The incidence rates of herpes zoster seemed to be high during the period of high ambient temperature and strong ultraviolet radiation (from May to October).Whenever ambient temperature increased 1°C per month, the incidence rate of herpes zoster increased by 0.072 per 10,000 persons per month. Whenever ultraviolet radiation increased 1 MJ m-2 per month, the incidence rate of herpes zoster increased by 0.313 per 10 000 persons per month. There is a significant association between ambient temperature, ultraviolet radiation, and the development of herpes zoster in Taiwan. The incidence rate of herpes zoster is high during the period of high ambient temperature and strong ultraviolet radiation. Low ambient temperature and weak ultraviolet radiation might be beneficial for the prevention of herpes zoster.

Particulate Air Pollution and Progression to Kidney Failure With Replacement Therapy: An Advanced CKD Registry-Based Cohort Study in Taiwan.

RATIONALE & OBJECTIVE: Limited evidence concerns fine particulate matter (with aerodynamic diameter ≤ 2.5µm [PM2.5]) exposure and the risk for kidney failure with replacement therapy (KFRT). This study assessed whether PM2.5 exposure was associated with progression of chronic kidney disease (CKD) to KFRT. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 6,628 adult patients with CKD were recruited from the Advanced CKD Program in Taiwan between 2003 and 2015. EXPOSURE: Satellite-based spatiotemporal models were used to calculate each individual's 1-year PM2.5 exposure before the date of enrollment into the Advanced CKD Program. OUTCOMES: Time to KFRT (defined as initiation of maintenance hemodialysis, peritoneal dialysis, or kidney transplantation) and time to all-cause mortality. ANALYTICAL APPROACH: Multivariable proportional hazard regression analyses were used to estimate the association of PM2.5 with KFRT and all-cause mortality. Restricted cubic splines were used to explore dose-response relationships. RESULTS: The study population included 6,628 adult patients with CKD who were aged 20 to 90 years. 941 KFRT events and 1,653 deaths occurred during follow-up. The adjusted HR for progression to KFRT was 1.19 (95% CI, 1.08-1.31) per 7.8µg/m3 greater PM2.5, an amount spanning the interquartile range. There was evidence of a dose-response relationship (adjusted HRs of 1.16 [95% CI, 0.90-1.51], 1.19 [95% CI, 0.94-1.52], and 1.42 [95% CI, 1.12-1.80] for low, medium, and high PM2.5 levels). There was no significant association between PM2.5 and all-cause mortality (adjusted HR, 1.01 [95% CI, 0.95-1.08]). LIMITATIONS: Misclassification of PM2.5 exposure assessment and the potential for residual confounding. CONCLUSIONS: Our findings suggest that long-term exposure to PM2.5 is associated with increased risk for progression to KFRT in patients with CKD.

Effect of Implementing Electronic Toll Collection in Reducing Highway Particulate Matter Pollution.

Highway vehicle emissions can result in adverse health problems to nearby residents and workers, especially during traffic congestion. In response, the policy to implement electronic toll collection (ETC) has helped alleviate traffic congestion, as compared to manual toll collection (MTC) and has led to reduced air pollution and improved public health. However, the effect of ETC in reducing particulate matter polluting the air is not well understood, especially in the ultrafine particle (UFP) range (particle diameter <100 nm). To the best of our knowledge, this is the first study to investigate how ETC affects the traffic pattern and air quality, especially UFP and PM2.5. We selected a site in Tainan, Taiwan, and measured UFP and PM2.5 concentrations before and after the construction of the ETC system. The computed traffic volumes during peak travel periods (7:00 AM to 9:00 AM and 4:00 PM to 6:00 PM) respectively, accounted for approximately 23-25% and 14-18% before and after the implementation of ETC, indicating that peak traffic volumes were more homogeneous after ETC. Moreover, the results indicate that the full implementation of ETC can help reduce UFP number concentrations and PM2.5 mass concentrations in the highway downwind area by 4 × 103 #/cm3 and 20.5 µg/m3, respectively. After the full implementation of the ETC, significant reductions in both the UFP number concentration and PM2.5 mass concentration were seen. Furthermore, excessive lifetime cancer risks (ELCR) from exposure to PM2.5 and UFP together were reduced 49.3% after the implementation of the ETC. Accordingly, ETC not only helps alleviate traffic congestion but also reduces traffic emissions and lifetime cancer risk for people living or working near highways.

Fine particulate matter exposure during pregnancy and infancy and incident asthma.

BACKGROUND: Lung development is a multistage process from conception to the postnatal period, disruption of which by air pollutants can trigger later respiratory morbidity. OBJECTIVE: We sought to evaluate the effects of weekly average fine particulate matter (particulate matter with an aerodynamic diameter less than 2.5 µm [PM2.5]) exposure during pregnancy and infancy on asthma and identify vulnerable times to help elucidate possible mechanisms of the effects of PM2.5 on asthma symptoms. METHODS: A birth cohort study including 184,604 children born during 2004-2011 in Taichung City was retrieved from the Taiwan Maternal and Child Health Database and followed until 2014. A daily satellite-based hybrid model was applied to estimate PM2.5 exposure for each subject. A Cox proportional hazard model combined with a distributed lag nonlinear model was used to evaluate the associations of asthma with PM2.5 exposure during pregnancy and infancy. RESULTS: The birth cohort contained 34,336 asthmatic patients, and the mean age of children given a diagnosis of asthma was 3.39 ± 1.78 years. Increased exposure to PM2.5 during gestational weeks 6 to 22 and 9 to 46 weeks after birth were significantly associated with an increased incidence of asthma. The exposure-response relationship indicated that the hazard ratio (HR) of asthma increased steeply at PM2.5 exposure of greater than 93 µg/m3 during pregnancy. Additionally, the HRs remained significant with postnatal exposure to PM2.5 between 26 and 72 µg/m3 (range, 1.01-1.07 µg/m3), followed by a sharp increase in HRs at PM2.5 exposure of greater than 73 µg/m3. CONCLUSION: Both prenatal and postnatal exposures to PM2.5 were associated with later development of asthma. The vulnerable time windows might be within early gestation and midgestation and infancy.

Fine particulate matter is a potential determinant of Alzheimer's disease: A systemic review and meta-analysis.

Air pollution is a modifiable and preventable factor, and it is a possible risk factor for dementia. However, evidence from epidemiological studies is still limited. We conducted a systematic review and meta-analysis to summarize the epidemiological evidence for long-term effects of particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5) on dementia/Alzheimer's disease (AD). Our inclusion criteria for eligible studies were: longitudinal cohort study design, no overlap in study population, age of study subject ≥50 years, detailed description of exposure assessment for PM2.5, outdoor assessment of exposure to PM2.5, usage of a clear definition of dementia/AD, and accessibility of sufficient information for meta-analysis. Six databases were searched for eligible studies. The random-effect model was used to synthesize the associations between PM2.5 and dementia. After exclusion of all irrelevant studies, we analyzed the results of four cohort studies conducted in Canada, Taiwan, the UK, and the US during 2015-2018 among more than 12 million elderly subjects aged ≥50 years (N = 12,119,853). Our meta-analysis reveals that exposure to a 10 µg/m3 increase in PM2.5 was significantly and positively associated with dementia (pooled HR = 3.26, 95% CI: 1.20, 5.31). In subgroup analyses, exposure to a 10 µg/m3 increase in PM2.5 was found to be positively associated with AD (pooled HR = 4.82, 95% CI: 2.28, 7.36). Analysis of current epidemiological research on PM2.5 and dementia confirmed that exposure to PM2.5 was positively associated with a higher risk for dementia. However, it is to be noted that the included studies mainly relied on claim-based diagnosis and showed large differences in methods of exposure assessment, hence further epidemiological studies with well validated outcomes and with standardized exposure assessment models are required to ascertain the relationship between PM2.5 and dementia/AD.

Air Pollution as a Potential Determinant of Rheumatoid Arthritis: A Population-based Cohort Study in Taiwan.

BACKGROUND: Limited studies have explored the relationship between air pollution and rheumatoid arthritis (RA), with the results being somewhat inconsistent. METHODS: This was a retrospective cohort study that included 322,301 subjects aged 30-50 years, selected from the National Health Insurance Research Database in Taiwan, were followed from 2001 to 2010. We used a time-dependent extended Cox model and incorporated time-dependent variables to estimate the associations between the annual mean concentrations of air pollutants with RA, including carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), particles with an aerodynamic diameter less than 10 µm (PM10), and sulfur dioxide (SO2), and reported the hazard ratio (HR) and 95% confidence interval (CI). RESULTS: Newly diagnosed RA was positively associated with a 100-ppb increase in CO (adjusted HR = 1.17 [95% CI = 1.16, 1.18]), a 10-ppb increase in NO2 (1.54 [1.45, 1.64]), a 10-ppb increase in O3 (1.37 [1.33, 1.41]), and a 1 ppb in SO2 (1.02 [1.00, 1.04]). There was no association between a 10-µg/m increase in PM10 and RA (1.02 [0.99, 1.05]). CONCLUSIONS: Our finding suggests that O3 and traffic-related air pollutants (CO and NO2) may be positively associated with incident RA. This is an important finding given that many individuals are exposed to similar levels of O3 and NO2 globally.