Two-pollutant Models Research Articles

Effects of ambient air pollution exposure on frequency of hospital admissions for appendicitis in Taipei, Taiwan

TPS 681: Short-term health effects of air pollutants 1, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM The relationship between exposure to ambient air pollutants and hospital admissions for appendicitis is not known. This study examined whether an association existed between air contaminant levels and frequency of hospital admissions for appendicitis in Taipei, Taiwan. Ambient air pollution and hospital admission data for Taipei were obtained for 2009-2013. Relative risk (RR) of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single pollutant model, on warm days (> 23°C), number of appendicitis admissions was significantly associated with particulate matter (PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3). On cool days (< 23°C), a significant rise in number of admissions for appendicitis was related to PM10, NO2, and O3 concentrations. In the two-pollutant models, on warm days, NO2 and O3 were significantly associated with increased number of admissions for appendicitis when combined with each of the other pollutants. On cool days, NO2, O3, and PM10 remained significant for higher appendicitis admission cases in all two-pollutant models. In conclusion, higher levels of ambient air pollutants may be associated with increase in the risk of hospital admissions for appendicitis in Taipei.

Low-level air pollution and incidence of asthma among adults: pooled analysis of 2 European cohorts in the ELAPSE project

TPS 684: Long-term health effects of air pollutants 1, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background/Aims: Air pollution has been linked to asthma onset in adults, yet few studies have investigated the effects of low-level pollution below current EU and WHO limit values or guidelines. Within the multicenter ‘Effects of Low-Level Air Pollution: A Study in Europe’ (ELAPSE) study, we examined the association of long-term exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2), black carbon (BC), and ozone (O3) with incidence of asthma in European adults. Methods: We pooled data from 2 cohorts from Denmark and Sweden harmonizing individual and area-level variables. Annual mean concentrations of PM2.5, NO2, BC and O3 were centrally modelled for Europe for 2010 by hybrid land use regression models (100 m resolution). We used stratified Cox proportional hazard models to investigate the association between residential pollution (single and multi-pollutant models) and asthma incidence defined as first ever hospital admission, adjusting for sex, smoking (status, duration, intensity), body mass index, marital status, employment, education and income on a neighbourhood level. Results: Of 50,163 persons, 888 developed asthma during the mean follow-up of 15.6 years. The mean concentrations of PM2.5, NO2 and BC were 10.9 μg/m3, 21.7 μg/m3 and 0.98 10-5/m, respectively. Statistically significant associations were found with NO2 and BC with adjusted hazard ratios and 95% CIs of 1.14 (1.04-1.25) per 10 µg/m3 and 1.15 (1.03-1.28) per 0.5 10-5/m, nonsignificant positive with PM2.5 (1.18; 0.91-1.53) per 5 μg/m3, and none with O3. The NO2 estimate remained unchanged in two-pollutant models with PM2.5, O3, or BC, whereas the BC estimate remained robust in the model with PM2.5 or O3, but attenuated in the model with NO2. The association with PM2.5 attenuated to negative in models with NO2 or BC. Conclusion: Long-term exposure to NO2 and BC was associated with asthma onset in adults, even at levels below current EU limit values.

Hourly Exposure to Ultrafine Particle Metrics and the Onset of Myocardial Infarction in Augsburg, Germany

OPS 56: Ultrafine particles exposure and health effects, Beatrix Theater, August 27, 2019, 4:30 PM - 5:30 PM Background: Epidemiological evidence on the health effects of ultrafine particles (UFP) remains insufficient to infer a causal relationship, which is largely due to the different size ranges and exposure metrics examined across studies. Moreover, evidence regarding the association between UFP and cardiovascular disease at a sub-daily timescale is lacking. Objective: To investigate the relationship between different particle metrics, including particle number (PNC), length (PLC), and surface area (PSC) concentrations, and myocardial infarction (MI) at an hourly timescale. Methods: We collected hourly air pollution and meteorological data from fixed urban background monitoring sites and hourly nonfatal MI cases from the MONICA/KORA MI registry in Augsburg, Germany during 2005-2015. We conducted a time-stratified case-crossover analysis with conditional logistic regression to estimate the association between hourly particle metrics and MI cases, adjusted for air temperature and relative humidity. We also examined the independent effects of a certain particle metric in two-pollutant models by adjusting for co-pollutants, including particulate matter with an aerodynamic diameter ≤10 µm or 2.5 µm (PM10, PM2.5), nitrogen dioxide, ozone, and black carbon. Results: Overall, a total of 5,898 cases of nonfatal MI cases were recorded. Interquartile range increases in PNC within the size range of 10-100 nm (UFP), PLC, and PSC were associated with an increase of MI six hours later by 3.27% (95% confidence interval [CI]: 0.27%, 6.37%), 5.71% (95% CI: 1.79%, 9.77%), and 5.56% (95% CI: 1.11%, 10.20%), respectively. No association was observed for PNC within the size range of 100-500 nm. The effect estimates for PLC and PSC remained similar after adjustment for PM and gaseous pollutants. The associations were not modified by individual characteristics, co-pollutants, or air temperature. Conclusions: Transient exposure to particle length and surface area concentrations may trigger the onset of myocardial infraction.

The relationship between air pollution exposure and the risk of diabetic retinopathy

PDS 67: Outdoor air pollution cardiometabolic effects, Exhibition Hall (PDS), Ground floor, August 27, 2019, 4:30 PM - 5:30 PM Background/Aim: Exposure to air pollution has been linked to adverse effects on vascular diseases. However, the effects of air pollution exposure on diabetic retinopathy (DR), a form of vascular disease, have not been studied. The aim of this study was to determine the association between ambient air pollution exposure and diabetic retinopathy occurrence. Material and Methods Retrospective cohort study design was applied for investigating the long-term effect of ambient air pollution on DR occurrence among diabetics. Newly diagnosed diabetes mellitus (DM) cases during 2003-2012 from the National Health Insurance Research Database (NHIRD) – Longitudinal Health Insurance Database 2005 (LHID2005) were included in the study cohort. Yearly air exposure levels were obtained from the Taiwan EPA air monitoring station. Kriging method was used to interpolate concentrations of air pollutants in township levels. We linked yearly townships exposure levels with townships of residence in each year, and calculated the average concentrations of follow-up period as personal exposure. The Cox proportional hazard models were performed adjusting for sex, age of DM onset and comorbidities. Results: A total of 17,403 subjects with newly diagnosed DM were included in the study. Among them, 585 newly diagnosed DR cases were found during the follow-up periods (mean: 5.6 years). The hazard ratio (HR) of DR occurrence associated with per 10 μg/m3 increase in PM2.5, PM2.5-10, 1 ppb in nitrogen dioxide (NO2) and sulfur dioxide (SO2), were 2.06 (95% confidence interval, CI: 1.60-2.66), 1.71 (95%CI: 1.39-2.10), 1.05 (95%CI: 1.03-1.08), and 1.23 (95%CI: 1.13-1.34), respectively. In two-pollutant models, the effects of PM2.5, PM2.5-10, NO2 and SO2 remained robust after adjusting for other air pollutants. Conclusion: Exposure to higher levels of air pollution was associated with increased risk of DR occurrence in diabetic patients.

The effects of ambient NO2 and PM2.5 exposure on asthma-related outcomes in school children residing in informal settlements in South Africa.

OPS 52: Air pollution and respiratory health, Room 110, Floor 1, August 28, 2019, 10:30 AM - 12:00 PM Background/Aim: No previous epidemiological study has investigated the independent effect of long-term ambient nitrogen dioxide (NO2) and particulate matter smaller than 2.5 µm in diameter (PM2.5) exposure on asthma-related outcomes among school children in Africa. This study aimed to investigate these effects in a cohort of school children in the Western Cape Province of South Africa. Methods: Grade-4 school children (n = 522) residing in four informal settlements were followed for a 12-months period. Spirometry and fractional exhaled nitric-oxide (FeNO) measurements were conducted on each child in addition to the International Study on Asthma and Allergy in Children (ISAAC) questionnaire that was administered to the parent/caregiver at baseline and follow-up. Annual NO2 and PM2.5 levels were estimated for each child’s home using land-use regression modelling. Two-pollutant models were constructed to assess the independent effects of both ambient NO2 and PM2.5 on incident asthma-associated outcomes adjusting-for host characteristics, indoor exposures and residential area. Results: The annual average concentration of PM2.5 and NO2 in the four study areas (10.01 μg/m3 and 16.62 µg/m3 respectively), were below the South Africa National Ambient Air Quality Standards (20 μg/m3 and 40 µg/m3, respectively) for both pollutants. An interquartile range (IQR) increase of 14.2 µg/m3 in NO2 was associated with an increased risk of new onset ocular-nasal symptoms (adjusted odds ratio [aOR]: 1.63, 95% Confidence Interval [CI]: 1.01 – 2.60), wheezing (aOR: 3.57, 95% CI: 1.18 – 10.92), symptom score ≥2 (aOR: 1.71, 95% CI: 1.02 – 2.86), and allergic airway inflammation defined as FeNO > 35 ppb (aOR: 3.10, 95% CI: 1.10 – 8.71), independent of PM2.5 exposures. Conclusion: This study provides evidence of an effect of ambient NO2 below national and international guidelines, independent of PM2.5 exposure, on 12-months incidence of asthma-related outcomes among children residing in informal settlements of South Africa.

P4334Effects of Asian dust on blood pressure and blood cell counts: a cross-sectional study of health check-up data

Abstract Introduction Asian dust (AD) is one of the health care problems because AD increases risk for mortality, respiratory, and cardiovascular disease. Previous animal studies showed that particulate matter from AD induced oxidative stress and systemic inflammation, increased blood pressure and heart rate, and decreased cardiac contraction. However, few reports show association of AD with increased blood pressure in human healthy subjects. Purpose The aim of this study was to investigate effects of AD on blood pressure and blood cell counts in human. Methods Using generalized linear models, we estimated the association between short-term exposure to AD and systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and white blood cell (WBC) count in 296,168 participants aged 20 and older (men n=168,579, 56.9%) who underwent medical check-ups and had no anti-hypertensive agents between April 2005 and March 2015 in a health check-up center in Japan. AD days were the days on which AD events occurred, which were defined as decreased visibility (&lt;10km) due to AD monitored by local meteorological observatory. Propensity score matching analysis was performed to reduce the effects of possible confounders such as age, sex, mean temperature, humidity. In multivariable generalized linear models, data of other air pollutant such as SO2, NO2, Ox or suspended particulate matter was used as covariate. Results During study period, 61 AD days were observed, and there were 4,670 participants undergoing medical check-ups on AD days. In the propensity score matched population (n=4,670, each), short-term exposure to AD was significantly associated with an increased risk of higher SBP, DBP, HR, or WBC count [β=1.303, 95% confidence interval (CI) 0.577 to 2.029 for SBP, β=0.630, 95% CI 0.122 to 1.138 for DBP, β=0.987, 95% CI 0.410 to 1.563 for HR, β=150.0, 95% CI 64.9 to 235.1 for WBC]. These significant associations were also observed in two-pollutant models. In subgroup analysis according to age, AD exposure had greater impact on SBP, DBP, and HR in younger people (20 to 40 years old), but WBC count in middle-high age (51 years and older). GLM analysis according to age category Conclusions The present study showed that short-term exposure to AD was associated with higher SBP, DBP, HR and WBC count. Short-term exposure to AD may exacerbate sympathetic nervous system for the young and immune system for the elderly.

Long-term exposure to ultrafine particles and cause-specific mortality in the Rome Longitudinal Study

OPS 51: Air pollution and mortality: what’s new? Beatrix Theater, August 26, 2019, 4:30 PM - 5:30 PM Background/Aim: Few studies evaluated the association between long-term exposure to ultrafine particles (UFP) and mortality. We aimed to study the association between UFP and mortality in a large administrative cohort (Rome Longitudinal Study, RoLS) and to evaluate whether the role of UFP is independent of other exposures. Methods: We selected 1,009,434 30+ year olds living in the Rome urban area, and we followed them from 2001 to 2013. We used land use regression models for PNC (particle number concentrations) as proxy for UFP, NO2, PM2.5, PM2.5 absorbance (as proxy for soot), and zinc component of PM2.5 (as proxy for non-tail-pipe emissions). We used the acoustic model SoundPLAN7.4 to assess road traffic noise indicators (Lden, Lnight). All exposures were attributed to the residential address of each subject. We analyzed non-accidental, cardiovascular, and ischemic heart disease (IHD) mortality. We applied Cox proportional hazard models adjusted for age, sex, education, place of birth, marital status, occupation, area-level socioeconomic position. We performed single-pollutant and two-pollutant models. Results: The average population exposure was 16,014 (interquartile range, iqr=2,659) n/cm3 PNC, 47 (iqr=8) µg/m3 NO2, 20 (iqr=2) µg/m3 PM2.5, 2.8 (iqr=0.3) 10–5/m PM2.5-absorbance, 25 (iqr=3.4) ng/m3 PM2.5-Zn, 61 (iqr=11) dB. The correlation between UFP and the other exposures ranged from 0.45 (UFP-noise) to 0.61 (UFP-PM2.5). We observed 166,787 deaths for non-accidental causes, 69,034 for cardiovascular causes, and 25,092 for ischemic heart disease. We estimated an increase in non-accidental (Hazard Ratio [HR]=1.010, 95%CI:1.004-1.016), cardiovascular (HR=1.029, 95%CI:1.020-1.038), and IHD (HR=1.032, 95%CI:1.016-1.047) mortality, per iqr increments in PNC. Results were robust to adjustment for all other exposures for cardiovascular and IHD mortality. For non-accidental mortality, adjustment for NO2 and PM2.5-absorbance substantially decreased the PNC effect estimates. Conclusions: We found an effect of UFP exposure on cardiovascular mortality independent of the concomitant exposure to other air pollutants and traffic noise.

Association between air pollution and venous thromboembolism

PDS 67: Outdoor air pollution cardiometabolic effects, Exhibition Hall (PDS), Ground floor, August 27, 2019, 4:30 PM - 5:30 PM Background: Air pollution is responsible for a large burden of diseases worldwide. Contrary to other cardiovascular diseases, little and contrasting evidence has been provided on the association of air pollution with venous thromboembolism. We investigated the association between short-term exposure to air pollution and hospital admissions for deep vein thrombosis (DVT) and pulmonary embolism (PE) in the city of Rome. Methods: We conducted a time-series analysis from 2001 to 2016 of daily levels of air pollution (PM10 and PM2.5 and nitrogen dioxide, NO2) and daily counts of urgent hospital admissions for DVT and PE. An over-dispersed Poisson model was applied to study the associations at different time lags after controlling for several time varying covariates. Additionally, we evaluated two-pollutant models and the influence of selected pre-existing medical conditions in subgroup analyses. Results: In total, 37,998 urgent hospital admissions for DVT and 19,667 for PE were recorded during the study period. The larger associations were observed at same day (lag 0) with increased risks of 1.60% (95% CI=0.53; 2.69), 0.29% (-1.22; 1.83) and 3.98% (2.97; 5.00) for DVT and of 1.42% (-0.02; 2.88), 0.66% (-1.35; 2.71) and 4.64% (3.24; 6.05) for PE hospital admissions, corresponding to 10μg/m3 increments of PM10, PM2.5 and NO2, respectively. The association with NO2 decreased substantially at lag 2-5 days before exposure. Associations with PE were stronger than those with DVT. Subgroup analyses evidenced larger effects in elderly for DVT while no differences resulted for other conditions. Estimates for NO2 were robust after adjustment for PM10 and PM2.5. Conclusions: Short-term NO2 exposure was associated with increased hospital admissions for deep vein thrombosis and pulmonary embolism in this long time series.

Short-term Exposures to Particulate Matter Gamma Radiation Activities and Biomarkers of Systemic Inflammation and Endothelial Activation in COPD Patients

Abstract Background We hypothesized that particulate matter (PM) gamma activity (gamma radiation associated with PM) is associated with systemic effects. Objective Examine short-term relationships between ambient and indoor exposures to PM gamma activities with systemic inflammation and endothelial activation in chronic obstructive pulmonary disease (COPD) patients. Methods In 85 COPD patients from Eastern Massachusetts, USA from 2012 to 2014, plasma C-reactive protein (CRP), interleukin-6 (IL-6), and soluble vascular cell adhesion molecule-1 (sVCAM-1) were measured seasonally up to four times. We used US EPA RadNet data measuring ambient gamma radiation attached to PM adjusted for background radiation, and estimated in-home gamma radiation exposures using the ratio of in-home-to-ambient sulfur in PM2.5. Linear mixed-effects regression models were used to determine associations between moving averages of PM gamma activities through the week before phlebotomy with these biomarkers. We explored ambient and indoor PM2.5, black carbon (BC), and NO2 as confounders. Results Ambient and indoor PM gamma activities measured as energy spectra classes 3 through 9 were positively associated with CRP and IL-6. For example, averaged from phlebotomy day through previous 6 days, each IQR increase in indoor PM gamma activity for each spectra class, was associated with an CRP increase ranging from 7.45% (95%CI: 2.77, 12.4) to 13.4% (95%CI: 5.82, 21.4) and for ambient exposures were associated with an increase of 8.75% (95%CI: −0.57, 18.95) to 14.8% (95%CI: 4.5, 26.0). Indoor exposures were associated with IL-6 increase of 3.56% (95%CI: 0.31, 6.91) to 6.46% (95%CI:1.33, 11.85) and ambient exposures were associated with an increase of 0.03% (95%CI: −6.37, 6.87) to 3.50% (95%CI: −3.15, 10.61). There were no positive associations with sVCAM-1. Sensitivity analyses using two-pollutant models showed similar effects. Conclusions Our results demonstrate that short-term exposures to environmental PM gamma radiation activities were associated with systemic inflammation in COPD patients.

Ambient air pollution is associated with pediatric pneumonia: a time-stratified case\u2013crossover study in an urban area

BackgroundPneumonia, the leading reason underlying childhood deaths, may be triggered or exacerbated by air pollution. To date, only a few studies have examined the association of air pollution with emergency department (ED) visits for pediatric pneumonia, with inconsistent results. Therefore, we aimed to elucidate the impact of short-term exposure to particulate matter (PM) and other air pollutants on the incidence of ED visits for pediatric pneumonia.MethodsPM2.5, PM10, and other air pollutant levels were measured at 11 air quality-monitoring stations in Kaohsiung City, Taiwan, between 2008 and 2014. Further, we extracted the medical records of non-trauma patients aged ≤17 years and who had visited an ED with the principal diagnosis of pneumonia. A time-stratified case–crossover study design was employed to determine the hazard effect of air pollution in a total of 4024 patients.ResultsThe single-pollutant model suggested that per interquartile range increment in PM2.5, PM10, nitrogen dioxide (NO2), and sulfur dioxide (SO2) on 3 days before the event increased the odds of pediatric pneumonia by 14.0% [95% confidence interval (CI), 5.1–23.8%], 10.9% (95% CI, 2.4–20.0%), 14.1% (95% CI, 5.0–24.1%), and 4.5% (95% CI, 0.8–8.4%), respectively. In two-pollutant models, PM2.5 and NO2 were significant after adjusting for PM10 and SO2. Subgroup analyses showed that older children (aged ≥4 years) were more susceptible to PM2.5 (interaction p = 0.024) and children were more susceptible to NO2 during warm days (≥26.5 °C, interaction p = 0.011).ConclusionsShort-term exposure to PM2.5 and NO2 possibly plays an important role in pediatric pneumonia in Kaohsiung, Taiwan. Older children are more susceptible to PM2.5, and all children are more susceptible to NO2 during warm days.

Ambient Particulate Air Pollution and Daily Mortality in 652 Cities

BackgroundThe systematic evaluation of the results of time-series studies of air pollution is challenged by differences in model specification and publication bias.MethodsWe evaluated the associations of inhalable particulate matter (PM) with an aerodynamic diameter of 10 μm or less (PM10) and fine PM with an aerodynamic diameter of 2.5 μm or less (PM2.5) with daily all-cause, cardiovascular, and respiratory mortality across multiple countries or regions. Daily data on mortality and air pollution were collected from 652 cities in 24 countries or regions. We used overdispersed generalized additive models with random-effects meta-analysis to investigate the associations. Two-pollutant models were fitted to test the robustness of the associations. Concentration–response curves from each city were pooled to allow global estimates to be derived.ResultsOn average, an increase of 10 μg per cubic meter in the 2-day moving average of PM10 concentration, which represents the average over the current and previous day, was associated with increases of 0.44% (95% confidence interval [CI], 0.39 to 0.50) in daily all-cause mortality, 0.36% (95% CI, 0.30 to 0.43) in daily cardiovascular mortality, and 0.47% (95% CI, 0.35 to 0.58) in daily respiratory mortality. The corresponding increases in daily mortality for the same change in PM2.5 concentration were 0.68% (95% CI, 0.59 to 0.77), 0.55% (95% CI, 0.45 to 0.66), and 0.74% (95% CI, 0.53 to 0.95). These associations remained significant after adjustment for gaseous pollutants. Associations were stronger in locations with lower annual mean PM concentrations and higher annual mean temperatures. The pooled concentration–response curves showed a consistent increase in daily mortality with increasing PM concentration, with steeper slopes at lower PM concentrations.ConclusionsOur data show independent associations between short-term exposure to PM10 and PM2.5 and daily all-cause, cardiovascular, and respiratory mortality in more than 600 cities across the globe. These data reinforce the evidence of a link between mortality and PM concentration established in regional and local studies. (Funded by the National Natural Science Foundation of China and others.)

Hourly associations between ambient air pollution and emergency ambulance calls in one central Chinese city: Implications for hourly air quality standards

BackgroundMost studies on the short-term health effects of air pollution have been conducted on a daily time scale, while hourly associations remain unclear. MethodsWe collected the hourly data of emergency ambulance calls (EACs), ambient air pollution, and meteorological variables from 2014 to 2016 in Luoyang, a central Chinese city in Henan Province. We used a generalized additive model to estimate the hourly effects of ambient air pollutants (PM2.5, PM10, SO2, and NO2) on EACs for all natural causes and cardiovascular and respiratory morbidity, with adjustment for potential confounding factors. We further examined the effect modification by temperature, relative humidity, wind speed, and atmospheric pressure using stratified analyses. ResultsIn the single-pollutant models, PM2.5, PM10, SO2, and NO2 were associated with an immediate increase in all-cause morbidity at 0, 0, 12, 10 h, separately, after exposure to these pollutants (excess risks: 0.19% (95% confidence interval (CI): 0.03%, 0.35%), 0.13% (95% CI: 0.02%, 0.24%), 0.28% (95% CI: 0.01%, 0.54%) and 0.52% (95% CI: 0.06%, 0.99%), respectively). These effects remained generally stable in two-pollutant models. SO2 and NO2 were significantly associated with an immediate increase in risk of cardiovascular morbidity, but the effects on respiratory morbidity were relatively more delayed. The stratified analyses suggested that temperature could modify the association between PM2.5 and EACs, humidity and atmospheric pressure could modify the association between SO2 and EACs. ConclusionsOur study provides new evidence that higher concentrations of PM2.5, PM10, SO2, and NO2 may have transiently acute effects on all-cause morbidity and subacute effects on respiratory morbidity. SO2 and NO2 may also have immediate effects on cardiovascular morbidity. Findings of this study have important implications for the formation of hourly air quality standards.

Acute effects of fine particulate matter (PM2.5) on hospital admissions for cardiovascular disease in Beijing, China: a time-series study

BackgroundAir pollution and cardiovascular disease are increasing problems in China. However, the short-term association between fine particulate matter (PM2.5) and cardiovascular disease (CVD) is not well documented. The purpose of this study is to estimate the short-term effects of PM2.5 on CVD admissions in Beijing, China.MethodsIn total, 460,938 electronic hospitalization summary reports for CVD between 2013 and 2017 were obtained. A generalized additive model using a quasi-Poisson distribution was used to investigate the association between exposure to PM2.5 and hospitalizations for total and cause-specific CVD, including coronary heart disease (CHD), atrial fibrillation (AF), and heart failure (HF) after controlling for the season, the day of the week, public holidays, and weather conditions. A stratified analysis was also conducted for age (18–64 and ≥ 65 years), sex and season.ResultsFor every 10 μg/m3 increase in the PM2.5 concentration from the previous day to the current (lag 0–1) there was a significant increase in total CVD admissions (0.30, 95% CI: 0.20, 0.39%), with a strong association for older adults (aged ≥65 years), CHD (0.34, 95% CI: 0.22 to 0.45%) and AF (0.29, 95% CI, 0.03 to 0.55%). However, the observed increased risk was not statistically significant for HF hospitalizations. The associations in the single-pollutant models were robust to the inclusion of other pollutants in a two-pollutant model. No differences were found after stratification by sex and season.ConclusionsExposure to PM2.5 increased the risk of hospitalizations from CVD, especially for CHD, and appeared to have more influence in the elderly. Precautions and protective measures and efforts to reduce exposure to PM2.5 should be strengthened, especially for the elderly.

Associations between short-term exposure to fine particulate matter and acute exacerbation of asthma in Yancheng, China

Scarce evidence existed on the association between short-term exposure to fine particulate matter (PM2.5) and asthma in China. In this study, we aimed to explore the relationship of PM2.5 with acute asthma exacerbation in a coastal city of China. Cases of acute asthma exacerbation were identified from hospital outpatient visits in Yancheng, China, from 2015 to 2018. We utilized the generalized additive model linked by a quasi-Poisson distribution to assess the association between PM2.5 and daily acute asthma exacerbation. Different lag structures were built, and we conducted stratification analyses by gender, age, and season. Two-pollutant models were fitted, and concentration-response (C-R) curves were pooled. A total of 3,520 cases of acute asthma exacerbation were recorded, with a daily average of 3. We observed positive and significant associations of PM2.5 on lag 1, 2, lag 02, and lag 03 day. For each 10-μg/m3 increase in PM2.5 (lag 02), the associated increment in asthma was 3.15% (95% CI: 0.99%, 5.31%). The association remained after adjusting for gaseous co-pollutants. We observed significant PM2.5-asthma associations in males, patients ≤64 years, and during cold seasons. The C-R curves were positive and almost linear for total and strata-specific associations. In conclusion, this study provided robust evidence on the association of PM2.5 with acute asthma exacerbation, which may benefit future prevention strategy and policy making.

Associations between ambient air pollution and mortality from all causes, pneumonia, and congenital heart diseases among children aged under 5 years in Beijing, China: A population-based time series study

BackgroundPrevious studies have mainly focused on the associations between particulate matters and infant mortality. However, evidence regarding the associations between gaseous pollutants and mortality among children aged <5 years remains sparse. ObjectivesThe aim of this study was to investigate the associations between ambient air pollution and death among children aged <5 years in Beijing, China, and explore the impact of age, gender and specific causes of death on these associations. MethodsConcentrations of ambient air pollution and the number of deaths among children aged <5 years in Beijing from January 2014 to September 2016 were extracted from authoritative electronic databases. The associations were estimated for a single-month lag from the current month up to the previous 5 months (lag0-lag5) and moving averages of the current and previous months (lag01-lag05) using generalized additive Poisson regression (adjusted for time trends, season, meteorological variables and holidays). Subgroup analyses related to age, gender and specific diseases were performed. Two-pollutant models were used to evaluate the possible role of single pollutants. ResultsSulfur dioxide (SO2), nitrogen dioxide (NO2) and carbon monoxide (CO) demonstrated the strongest associations with death among children aged <5 years at lag0, and the estimates decreased or even turned negative with the increasing lag periods. For an interquartile range increase in SO2, NO2 and CO at lag0, the odds ratios (OR) were 1.332 (95% CI 1.152-1.539), 1.383 (95% CI 1.113-1.718) and 1.273 (95% CI 1.028-1.575). However, CO lost significance after adjusting for SO2 and NO2, and PM2.5 gained significance (OR 1.548, 95% CI 1.061-2.258) after adjusting for PM10. The ORs for SO2 and NO2 remained the most stable across all two-pollutant models. The associations for children aged 1–5 years were stronger than those reported for infants at lag0 but lower at the other lag months. The pollutant associations were stronger for congenital heart disease-related death than overall and pneumonia-related death. We did not find significant differences in terms of gender. ConclusionExposure to air pollution may increase the incidence of death among children aged <5 years. SO2 and NO2 may be the most stable pollutants reflecting associations between air pollution and death, deserving further attention. Children with congenital heart diseases are more susceptible to air pollution. Therefore, it is urgent to implement the clean air targets established by WHO and reduce the exposure of children to air pollution.

Ambient Air Pollution and Hospital Admissions for Peptic Ulcers in Taipei: A Time-Stratified Case-Crossover Study.

Very few studies have been performed to determine whether there is a relationship between air pollution and increases in hospitalizations for peptic ulcer, and for those that have occurred, their results may not be completely relevant to Taiwan, where the mixture of ambient air pollutants differ. We performed a time-stratified case-crossover study to investigate the possible association between air pollutant levels and hospital admissions for peptic ulcer in Taipei, Taiwan. To do this, we collected air pollution data from Taiwan's Environmental Protection Agency and hospital admissions for peptic ulcer data for the years 2009–2013 from Taiwan's National Health Insurance's research database. We used conditional logistic regression to analyze the possible association between the two, taking temperature and relative humidity into account. Risk was expressed as odds ratios and significance was expressed with 95% confidence intervals. In our single pollutant model, peptic ulcer admissions were significantly associated with all pollutants (PM10, PM2.5, SO2, NO2, CO, and O3) on warm days (>23 °C). On cool days (<23 °C), peptic ulcer admissions were significantly associated with PM10, NO2, and O3. In our two-pollutant models, peptic ulcer admissions were significantly associated NO2 and O3 when combined with each of the other pollutants on warm days, and with PM10, NO2, and O3 on cool days. It was concluded that the likelihood of peptic ulcer hospitalizations in Taipei rose significantly with increases in air pollutants during the study period.

Does ambient ozone air pollution trigger suicide attempts? A case cross-over analysis in Taipei

ABSTRACTEpidemiologic studies indicated that exposure to ambient air pollutants was associated with increased mortality rates attributed to suicide. The objective of this study was to investigate the potential relationship between ambient ozone (O3) levels and daily number of hospital admissions for suicide attempts in Taipei for the period 2008–2012 using a time-stratified case-crossover analysis. In the single-pollutant model (without adjustment for other pollutants), the risk of committing a suicide attempt increased by 9% on warm days and 27% on cool days for each interquartile range (IQR) rise in O3 levels, respectively. The concentration of O3 was thus significantly associated with daily number of suicide attempts both on warm and cool days. In the two-pollutant models, O3 levels remained significant after the inclusion of other air pollutants (particulate matter (PM10), PM2.5, sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO)) on cool days. However, on warm days, no significant correlation was found between O3 levels and reported daily number of suicide attempts. The relationship between O3 and suicide attempts appeared to be dependent upon temperature; however, the basis for these observations requires further investigation.

A Systematic Review and Meta-Analysis on Short-Term Particulate Matter Exposure and Chronic Obstructive Pulmonary Disease Hospitalizations in China.

We conducted a meta-analysis of short-term particulate matter (PM) exposure and chronic obstructive pulmonary disease (COPD) hospitalizations in China, including data from two-pollutant model. From PubMed and Web of Science, we selected case-crossover or time-series studies conducted in Mainland China, Hong Kong, Macao, or Taiwan to investigate the association between PM exposure and COPD hospitalizations. The meta-analysis was performed using data from both single-pollutant and two-pollutant models for PM2.5 and PM10. A total of 16 studies were included in our analysis. Short-term exposure to PM2.5 and PM10 were both significantly associated with COPD hospitalizations. The results remained robust in two-pollutant model, whereas subgroup analyses demonstrated a modest heterogeneity. Our review shows a small but obvious exposure-hospitalization effect in China. More studies are needed to generate the needed evidence, and advocacy is needed to stimulate initiation of solutions to the problem.

Short-term effect of ambient sulfur dioxide (SO2) on cause-specific cardiovascular hospital admission in Beijing, China: A time series study

Evidence of the short-term effect of SO2 on hospital admissions for cause-specific cardiovascular diseases (CVD) is still limited. This study aimed to examine the short-term associations between SO2 and cause-specific CVD hospital admission in Beijing. A total of 460,938 hospitalizations for total CVD were obtained from electronic hospitalization summary reports from 2013 to 2017. A time series analysis was conducted to investigate the association between SO2 exposure and hospitalizations for total and cause-specific CVD, including coronary heart disease (CHD), atrial fibrillation (AF), and heart failure (HF). Stratified analysis was also conducted by age group (18–64 years and ≥65 years), sex and season. A generalized additive quasi-Poisson model was used to examine the associations between SO2 and cause-specific CVD after controlling for seasonality, day of the week, public holidays, and weather conditions. We found an almost linear relationship between the exposure to SO2 and cause-specific CVD admissions. A 10 μg/m3 increase in the two-day average concentration (lag0-1) of SO2 was associated with an increase of 1.38% (95% CI:0.99%; 1.77%) in hospital admission for total CVD, 1.58% (95% CI: 1.16%; 2%) for CHD and 1.69% (95% CI:0.41%; 2.99%) for AF. Nevertheless, a statistically significant association was not observed for admissions for HF. The observed associations in the single-pollutant models were robust to the inclusion of pollutants in the two-pollutant model, but the estimate was attenuated when adjusting for fine particulate matter (PM2.5). No difference in the association was observed for the effect modifiers of sex, season and age. A statistically significant association between hospitalizations and SO2 was observed. The observed association between SO2 and hospitalization might not be independent of fine particulate matter (PM2.5), and further studies should be conducted to demonstrate the independent effect of SO2.

Association between Mortality and Short-Term Exposure to Particles, Ozone and Nitrogen Dioxide in Stockholm, Sweden.

In this study, the effects on daily mortality in Stockholm associated with short-term exposure to ultrafine particles (measured as number of particles with a diameter larger than 4 nm, PNC4), black carbon (BC) and coarse particles (PM2.5–10) have been compared with the effects from more common traffic-pollution indicators (PM10, PM2.5 and NO2) and O3 during the period 2000–2016. Air pollution exposure was estimated from measurements at a 20 m high building in central Stockholm. The associations between daily mortality lagged up to two days (lag 02) and the different air pollutants were modelled by using Poisson regression. The pollutants with the strongest indications of an independent effect on daily mortality were O3, PM2.5–10 and PM10. In the single-pollutant model, an interquartile range (IQR) increase in O3 was associated with an increase in daily mortality of 2.0% (95% CI: 1.1–3.0) for lag 01 and 1.9% (95% CI: 1.0–2.9) for lag 02. An IQR increase in PM2.5–10 was associated with an increase in daily mortality of 0.8% (95% CI: 0.1–1.5) for lag 01 and 1.1% (95% CI: 0.4–1.8) for lag 02. PM10 was associated with a significant increase only at lag 02, with 0.8% (95% CI: 0.08–1.4) increase in daily mortality associated with an IQR increase in the concentration. NO2 exhibits negative associations with mortality. The significant excess risk associated with O3 remained significant in two-pollutant models after adjustments for PM2.5–10, BC and NO2. The significant excess risk associated with PM2.5–10 remained significant in a two-pollutant model after adjustment for NO2. The significantly negative associations for NO2 remained significant in two-pollutant models after adjustments for PM2.5–10, O3 and BC. A potential reason for these findings, where statistically significant excess risks were found for O3, PM2.5–10 and PM10, but not for NO2, PM2.5, PNC4 and BC, is behavioral factors that lead to misclassification in the exposure. The concentrations of O3 and PM2.5–10 are in general highest during sunny and dry days during the spring, when exposure to outdoor air tend to increase, while the opposite applies to NO2, PNC4 and BC, with the highest concentrations during the short winter days with cold weather, when people are less exposed to outdoor air.