Increase In Respiratory Mortality Research Articles

Comparison for the effects of different components of temperature variability on mortality: A multi-country time-series study

BackgroundTemperature variability (TV) is associated with increased mortality risk. However, it is still unknown whether intra-day or inter-day TV has different effects. ObjectivesWe aimed to assess the association of intra-day TV and inter-day TV with all-cause, cardiovascular, and respiratory mortality. MethodsWe collected data on total, cardiovascular, and respiratory mortality and meteorology from 758 locations in 47 countries or regions from 1972 to 2020. We defined inter-day TV as the standard deviation (SD) of daily mean temperatures across the lag interval, and intra-day TV as the average SD of minimum and maximum temperatures on each day. In the first stage, inter-day and intra-day TVs were modelled simultaneously in the quasi-Poisson time-series model for each location. In the second stage, a multi-level analysis was used to pool the location-specific estimates. ResultsOverall, the mortality risk due to each interquartile range [IQR] increase was higher for intra-day TV than for inter-day TV. The risk increased by 0.59% (95% confidence interval [CI]: 0.53, 0.65) for all-cause mortality, 0.64% (95% CI: 0.56, 0.73) for cardiovascular mortality, and 0.65% (95% CI: 0.49, 0.80) for respiratory mortality per IQR increase in intra-day TV0–7 (0.9 °C). An IQR increase in inter-day TV0–7 (1.6 °C) was associated with 0.22% (95% CI: 0.18, 0.26) increase in all-cause mortality, 0.44% (95% CI: 0.37, 0.50) increase in cardiovascular mortality, and 0.31% (95% CI: 0.21, 0.41) increase in respiratory mortality. The proportion of all-cause deaths attributable to intra-day TV0–7 and inter-day TV0–7 was 1.45% and 0.35%, respectively. The mortality risks varied by lag interval, climate area, season, and climate type. ConclusionsOur results indicated that intra-day TV may explain the main part of the mortality risk related to TV and suggested that comprehensive evaluations should be proposed in more countries to help protect human health.

Assessing heat effects on respiratory mortality and location characteristics as modifiers of heat effects at a small area scale in Central-Northern Europe.

Heat effects on respiratory mortality are known, mostly from time-series studies of city-wide data. A limited number of studies have been conducted at the national level or covering non-urban areas. Effect modification by area-level factors has not been extensively investigated. Our study assessed the heat effects on respiratory mortality at a small administrative area level in Norway, Germany, and England and Wales, in the warm period (May-September) within 1996-2018. Also, we examined possible effect modification by several area-level characteristics in the framework of the EU-Horizon2020 EXHAUSTION project. Daily respiratory mortality counts and modeled air temperature data were collected for Norway, Germany, and England and Wales at a small administrative area level. The temperature-mortality association was assessed by small area-specific Poisson regression allowing for overdispersion, using distributed lag non-linear models. Estimates were pooled at the national level and overall using a random-effect meta-analysis. Age- and sex-specific models were also applied. A multilevel random-effects model was applied to investigate the modification of the heat effects by area-level factors. A rise in temperature from the 75th to 99th percentile was associated with a 27% (95% confidence interval [CI] = 19%, 34%) increase in respiratory mortality, with higher effects for females. Increased population density and PM2.5 concentrations were associated with stronger heat effects on mortality. Our study strengthens the evidence of adverse heat effects on respiratory mortality in Northern Europe by identifying vulnerable subgroups and subregions. This may contribute to the development of targeted policies for adaptation to climate change.

Impact of the COVID-19 pandemic in mortality due to respiratory diseases: A comparative analysis of 2021 and 2020 vs 2019 in Spain

IntroductionWe previously reported an increase in respiratory mortality in 2020 in Spain after COVID-19. It is unclear if this rise is sustained in the longer-term. We aimed to determine whether respiratory mortality in 2021 in Spain returned to pre-pandemic levels. Material and methodsIn an observational, large study using official National Institute of Statistics data, we explored deaths due to respiratory diseases, that is, all causes of death by the standard WHO list of diseases of the respiratory system plus COVID-19, tuberculosis and lung cancer. Using the latest available official data of Spain, we analyzed changes in the mortality pattern in Spain from January 2019 to December 2021. We endorsed STROBE guidance for observational research. ResultsThere were 98,714 deaths due to respiratory diseases in 2021 in Spain, corresponding to 21.9% of all deaths, becoming second in the ranking of causes of death. Respiratory diseases mortality in Spain has not returned to pre-pandemic levels in 2021, still with an increase of 30.3% (95% CI 30.2–30.4) compared to rates in 2019. All respiratory-specific causes of death decreased in 2021, except for lung cancer, that increased in women and decreased in men compared to 2019 (both p<0.05). In a multivariate analysis some established risk factors for respiratory diseases mortality were confirmed, such as male gender and older age; further, an association with reduced mortality in rural Spain was observed, still with a large geographical variability. ConclusionsThe COVID-19 pandemic has had a lasting impact on deaths due to respiratory diseases and certain specific causes of death in 2021, and it has disproportionately affected certain regions.

Impact of the COVID-19 pandemic in mortality due to respiratory diseases: A comparative analysis of 2021 and 2020 vs 2019 in Spain

IntroductionWe previously reported an increase in respiratory mortality in 2020 in Spain after COVID-19. It is unclear if this rise is sustained in the longer-term. We aimed to determine whether respiratory mortality in 2021 in Spain returned to pre-pandemic levels. Material and methodsIn an observational, large study using official National Institute of Statistics data, we explored deaths due to respiratory diseases, that is, all causes of death by the standard WHO list of diseases of the respiratory system plus COVID-19, tuberculosis and lung cancer. Using the latest available official data of Spain, we analyzed changes in the mortality pattern in Spain from January 2019 to December 2021. We endorsed STROBE guidance for observational research. ResultsThere were 98,714 deaths due to respiratory diseases in 2021 in Spain, corresponding to 21.9% of all deaths, becoming second in the ranking of causes of death. Respiratory diseases mortality in Spain has not returned to pre-pandemic levels in 2021, still with an increase of 30.3% (95% CI 30.2–30.4) compared to rates in 2019. All respiratory-specific causes of death decreased in 2021, except for lung cancer, that increased in women and decreased in men compared to 2019 (both p<0.05). In a multivariate analysis some established risk factors for respiratory diseases mortality were confirmed, such as male gender and older age; further, an association with reduced mortality in rural Spain was observed, still with a large geographical variability. ConclusionsThe COVID-19 pandemic has had a lasting impact on deaths due to respiratory diseases and certain specific causes of death in 2021, and it has disproportionately affected certain regions.

Heat-related cardiorespiratory mortality: Effect modification by air pollution across 482 cities from 24 countries

BackgroundEvidence on the potential interactive effects of heat and ambient air pollution on cause-specific mortality is inconclusive and limited to selected locations. ObjectivesWe investigated the effects of heat on cardiovascular and respiratory mortality and its modification by air pollution during summer months (six consecutive hottest months) in 482 locations across 24 countries. MethodsLocation-specific daily death counts and exposure data (e.g., particulate matter with diameters ≤ 2.5 µm [PM2.5]) were obtained from 2000 to 2018. We used location-specific confounder-adjusted Quasi-Poisson regression with a tensor product between air temperature and the air pollutant. We extracted heat effects at low, medium, and high levels of pollutants, defined as the 5th, 50th, and 95th percentile of the location-specific pollutant concentrations. Country-specific and overall estimates were derived using a random-effects multilevel meta-analytical model. ResultsHeat was associated with increased cardiorespiratory mortality. Moreover, the heat effects were modified by elevated levels of all air pollutants in most locations, with stronger effects for respiratory than cardiovascular mortality. For example, the percent increase in respiratory mortality per increase in the 2-day average summer temperature from the 75th to the 99th percentile was 7.7% (95% Confidence Interval [CI] 7.6–7.7), 11.3% (95%CI 11.2–11.3), and 14.3% (95% CI 14.1–14.5) at low, medium, and high levels of PM2.5, respectively. Similarly, cardiovascular mortality increased by 1.6 (95%CI 1.5–1.6), 5.1 (95%CI 5.1–5.2), and 8.7 (95%CI 8.7–8.8) at low, medium, and high levels of O3, respectively. DiscussionWe observed considerable modification of the heat effects on cardiovascular and respiratory mortality by elevated levels of air pollutants. Therefore, mitigation measures following the new WHO Air Quality Guidelines are crucial to enhance better health and promote sustainable development.

Short-term heat effects and effect modification by ambient air pollution on cardiovascular and respiratory mortality across 148 cities from 13 European countries – Results of the EXHAUSTION project

Background and Aim: Epidemiological evidence on the potential interactive effects of high air temperature and air pollution on cause-specific mortality remains inconclusive and limited to selected locations. We investigated the effects of temperature on cardiovascular and respiratory mortality and its effect modification by particulate matter with a diameter &amp;#x2264; 2.5 µm [PM₂.₅] and ozone [O₃] during summer months (May-September) in 148 cities across 13 European countries. Methods: For these cities, we obtained daily counts of cardiovascular and respiratory mortality and daily exposure data between 2000 and 2018. We used location-specific confounder-adjusted Quasi-Poisson regression with a tensor product between air temperature and the air pollutant. We extracted temperature estimates at low, medium, and high levels of pollutants defined as the 5th, 50th, and 95th percentile of location-specific air pollutant concentrations. A random-effects multilevel meta-analytical model was used to derive the country-specific and overall estimates. Results: High summer temperatures were associated with increased cardiovascular and respiratory mortality. We further observed modification of the heat effects by elevated levels of PM₂.₅ and O₃ in most locations, with stronger effects for respiratory than cardiovascular mortality. For example, the percent increase in respiratory mortality per increase in the 2-day average summer temperature from the 75th to the 99th percentile was 9.2% (95% Confidence Interval [CI] 8.9-9.4), 13.0% (95% CI 12.8, 13.2), and 19.8% (95% CI 19.5, 20.2) at low, medium, and high levels of PM₂.₅, respectively. Conclusion: We observed significant modification of the heat effects by elevated levels of PM₂.₅ and O₃ leading to an increased risk of cardiovascular and respiratory mortality. With both temperature and air pollutant concentrations foreseen to increase considering climate change, targeted adaptation and mitigation measures are crucial to enhance resilience and sustainable development in alignment with EU climate change policies. Keywords: Air temperature, air pollution, cause-specific mortality, effect modification, Europe

Daily Mortality/Morbidity and Air Quality: Using Multivariate Time Series with Seasonally Varying Covariances

Abstract We study the associations between daily mortality and short-term variations in the ambient concentrations of fine particulate matter (PM2.5), nitrogen dioxide (NO2) and ozone (O3) in four cities in Canada. First, a novel multivariate time series model within Bayesian framework is proposed for exposure assessment, where the response is a mixture of Gamma and Half-Cauchy distributions and the correlations between pollutants vary seasonally. A case-crossover design and conditional logistic regression model is used to relate exposure to disease data for each city, which then are combined to obtain a global estimate of exposure health effects allowing exposure uncertainty. The results suggest that every 10 ppb increase in O3 is associated with a 3.88% (95% credible interval [CI], 2.5%, 5.18%) increase in all-cause mortality, a 5.04% (2.84%, 7.43%) increase in circulatory mortality, a 7.87% (2.4%, 12.9%) increase in respiratory mortality, a 0.76% (0.19%, 1.35%) increase in all-cause morbidity and a 6.6% (0.58%, 12.7%) increase in respiratory morbidity. Similarly, every 10 ppb increase in NO2 is associated with a 2.13% (0.42%, 3.87%) increase in circulatory morbidity. The health impacts of PM2.5 are not found to be present once other pollutants are accounted for.

Short-term exposure to nitrogen dioxide and mortality: A systematic review and meta-analysis

BackgroundAmbient air pollution has been characterized as a leading cause of mortality worldwide and has been associated with cardiovascular and respiratory diseases. There is increasing evidence that short-term exposure to nitrogen dioxide (NO2), is related to adverse health effects and mortality. MethodsWe conducted a systematic review of short-term NO2 and daily mortality, which were indexed in PubMed and Embase up to June 2021. We calculated random-effects estimates by different continents and globally, and tested for heterogeneity and publication bias. ResultsWe included 87 articles in our quantitative analysis. NO2 and all-cause as well as cause-specific mortality were positively associated in the main analysis. For all-cause mortality, a 10 ppb increase in NO2 was associated with a 1.58% (95%CI 1.28%–1.88%, I2 = 96.3%, Eggers' test p < 0.01, N = 57) increase in the risk of death. For cause-specific mortality, a 10 ppb increase in NO2 was associated with a 1.72% (95%CI 1.41%–2.04%, I2 = 87.4%, Eggers' test p < 0.01, N = 42) increase in cardiovascular mortality and a 2.05% (95%CI 1.52%–2.59%, I2 = 78.5%, Eggers’ test p < 0.01, N = 38) increase in respiratory mortality. In the sensitivity analysis, the meta-estimates for all-cause mortality, cardiovascular and respiratory mortality were nearly identical. The heterogeneity would decline to varying degrees through regional and study-design stratification. ConclusionsThis study provides evidence of an association between short-term exposure to NO2, a proxy for traffic-sourced air pollutants, and all-cause, cardiovascular and respiratory mortality.

The Association Between Particulate Air Pollution and Respiratory Mortality in Beijing Before, During, and After the 2008 Olympic and Paralympic Games

To improve ambient air quality during the 2008 Summer Olympic and Paralympic Games, the Chinese Government and Beijing’s municipal government implemented comprehensive emission control policies in Beijing and its neighboring regions before and during this period. The goal of this study was to investigate the association between particulate air pollution and cause-specific respiratory mortality before, during and after the period of the Olympic Games. Further, we wanted to assess whether changes in pollutant concentrations were linked to changes in respiratory mortality. We obtained daily data on mortality due to respiratory diseases (coded as J00-J99 according to the International Classification of Diseases and Related Health Problems 10th revision [ICD10]) and pneumonia (ICD10: J12–18), meteorology, particulate matter less than 10 µm or 2.5 μm in diameter (PM10, PM2.5) and particle number size distribution from official monitoring networks and sites located on the Peking University campus between May 20 and December 1, 2008. We assessed the effects of particulate air pollution on daily respiratory mortality using confounder-adjusted Quasi-Poisson regression models. Furthermore, we estimated air pollution effects for three periods—before (May 20 to July 20, 2008), during (August 1 to September 20, 2008) and after (October 1 to December 1, 2008)—by including interaction terms in the models. We found associations between different particle metrics and respiratory and pneumonia mortality, with more pronounced effects in smaller particle size ranges. For example, an interquartile range increase of 7,958 particles/cm3 in ultrafine particles (particles &amp;lt;100 nm in diameter) led to a 16.3% (95% confidence interval 4.3%; 26.5%) increase in respiratory mortality with a delay of seven days. When investigating the sub-periods, results indicate that a reduction in air pollution during the Olympics resulted in reduced (cause-specific) respiratory mortality. This reduction was especially pronounced for pneumonia mortality. The findings suggest that even a short-term reduction in pollution concentrations may lead to health benefits and that smaller particles in the ultrafine size range may be particularly important for respiratory health.

Acute effects of particulate matter with different sizes on respiratory mortality in Shenzhen, China.

There are relatively few studies that focus on the health effects of exposure to size-specific particles on respiratory mortality in China. We aimed to examine the association between different particle sizes and mortality from cause-specific respiratory diseases. We used a time series model with a quasi-Poisson link to investigate the relationship between different particle sizes and mortality from respiratory diseases, chronic obstructive pulmonary diseases (COPD), pneumonia, and asthma in Shenzhen during 2014-2017. A total of 3716 mortalities due to respiratory diseases were collected. Both PM1 and PM2.5 were associated with mortality of overall respiratory diseases, COPD, and pneumonia. An interquartile range (IQR) increase in PM1 at lag03 was associated with a 12.21% (95% CI: 2.59%, 22.75%) increase in respiratory mortality, and each IQR increase in PM2.5 at lag03 corresponded to a 12.09% (95% CI: 2.52%, 22.56%) increase in respiratory mortality. PM1-2.5 was not associated with mortality from all-cause or cause-specific respiratory diseases. This study suggests that both PM1 and PM2.5 may increase the risk of mortality due to respiratory diseases in Shenzhen, China.

Multi-dimensional community characteristics in linking particulate matter pollution and cause-specific mortality: 72 communities of South Korea

Concentration-response function for exposure to ambient particulate matter (PM) and mortality (i.e., relative risk, RR) may be inequal across communities by socioeconomic conditions. Investigation on specific mechanisms of this inequality regarding susceptibility to PM, beyond non-specific “socioeconomic conditions”, would provide policy-relevant implications for tackling this inequality. However, such investigation via epidemiological studies is challenged by residual confounding by correlated mechanisms and different loss of life expectancy by PM exposures between communities. Here, we aimed to assess community characteristics including different aspects of socioeconomic deprivation, medical resources, health behaviors, air quality, and greenness in their relation to inequal RR for PM10 and cause-specific mortality in 72 municipalities in South Korea, 2006–2013, considering these challenges. We found that a 10 μg/m3 increase in PM10 on average across 46 days was associated with a 1.05% (95% CI: 0.24, 1.88) increase in all-cause mortality (ALL), 1.32% (95% CI: -0.29, 2.95) increase in cardiovascular mortality (CVD), and 6.47% (95% CI: 3.06, 10.00) increase in respiratory mortality (RES). The association between PM10 and mortality was higher in communities with higher ratio of SO2 to PM10 (ALL and RES), higher material deprivation (ALL, CVD, and RES), lower medical resources (CVD), higher prevalence of drinking (ALL and CVD), and lower prevalence of smoking (CVD and RES). Lag-structures showed smaller loss of life expectancy by PM exposures in communities with higher prevalence of smoking. Our findings suggest that PM-related health inequalities are shaped by a variety of mechanisms relating to susceptibility to PM exposures and different loss of life expectancy. Health policies controlling community characteristics may contribute to minimizing PM10-related health inequalities in those perspectives.

Community characteristics affecting lag-structure of short-term exposure effect of ambient particulate matter on mortality: contextual variation of cumulative exposure effect and mortality displacement in 72 municipalities of seven major cities of South K

Background: The association between ambient particulate matter (PM) and mortality may vary by community characteristics. Variation in lag-structure is related to how this association varies. This variation has not been well studied.Objectives: We assessed variation in lag-structure of short-term exposure to PM10 on mortality in 72 municipalities in seven major South Korean cities (2006-2013), regarding the modification by other pollutants, socioeconomic deprivation, medical resources, greenness, and health behaviors.Methods: We used municipality-specific Poisson regression models considering overdispersion. We applied constrained distributed lag models to estimate lag-structures for associations between cumulative PM10 exposure and mortality, up to 45 lag days of PM10. Lag-structures were adjusted for O3, weather, seasonality, and time. We performed random-effect meta-regressions with variable selection methods. Variable selections and changes in coefficients were interpreted based on a priori hypothesized pathways between community characteristics and mortality risk due to PM10.Results: A 10 µg/m3 increase in PM10 on average across 46 days was associated with a 1.05% (95% CI: 0.24, 1.88) increase in all-cause mortality (ALL), 1.32% (95% CI: -0.29, 2.95) increase in cardiovascular mortality (CVD), and 6.47% (95% CI: 3.06, 10.00) increase in respiratory mortality (RES). Mortality risk associated with PM10 was higher in communities with higher ratio of SO2 to PM10 (ALL and RES), higher socioeconomic deprivation (ALL, CVD, and RES), lower medical resources (CVD), higher prevalence of drinking (ALL and CVD), and lower prevalence of smoking (CVD and RES). Lag-structures differed by these community characteristics, suggesting that effects of cumulative PM10 exposure and mortality displacement may differ across communities.Conclusion: The association between PM10 and mortality may be higher in communities with higher SO2, higher socioeconomical deprivation, lower medical resources, higher prevalence of drinking, and lower prevalence of smoking. This contextual variation may result from variation in not only cumulative exposure effect of PM but also mortality displacement.

Shrinking lakes, air pollution, and human health: Evidence from California's Salton Sea

Due to increased water withdrawals and ongoing climate change, many inland lakes around the world are shrinking and dry lake beds can be significant sources of particulate matter air pollution. Using a natural experiment provided by the shrinking Salton Sea in California, this paper shows that each one-foot drop in lake elevation is associated with a 0.28 μg/m3 (2.6%) increase in PM2.5 concentrations. IV model results then show that Salton Sea-induced changes in PM2.5 over 1998–2014 led to increases in respiratory mortality of 1.4/yr.–15.6/yr. in the counties surrounding the lake, generating $13.2–$147.3 million in annual health costs.

Has respiratory emergencies changed during lockdown implemented for COVID-19 pandemic?

Sir, Coronavirus disease (COVID-19) is an infectious disease caused by novel coronavirus named as SARS Cov-2. It originated in the city of Wuhan, the capital of Hubei province of China in December 2019 and has been declared a pandemic by the World Health Organization.[12] The disease has now spread in more than 200 countries and even our country, India has been badly affected. More than 11 lacs cases and almost 20,000 deaths have occurred till date (20th July 2020). Our Honorable Prime Minister announced a “Janta curfew” on 22nd March 2020. Thereafter, a nationwide “Lockdown” was ordered which has been effective in slowing down the growth rate of pandemic. The unprecedented COVID-19 pandemic has seriously impacted people with pre-existing health conditions and has adversely affected the management of other diseases. Lockdown not only helped in containment of COVID-19 infection but reducing air pollution as evident by a bettering in the air quality index. The short-term effects of air pollution include reduction in pulmonary function, worsening of respiratory symptoms, non-infectious exacerbations of chronic obstructive pulmonary disease (COPD), bronchial asthma (BA), and an increase in respiratory mortality.[345] Patna is among one of the most polluted cities of India and air quality index is generally more than 300 in month of April–May 2020. Air quality index of Patna during lockdown period was generally less than 100 which is considered as satisfactory. Our hypothesis was that with betterment of air quality, we should expect a reduction in hospital admission for diseases like exacerbation of COPD/BA. So, we compared the morbidity and mortality due to respiratory emergencies in same period of 2020 with 2019. Primary objective of the study was to comparison of number of episodes' and type respiratory emergency in period of lockdown to same period last year. Materials and Methods This was retrospective analysis of all the patients admitted in Pulmonary Medicine department for diseases other than COVID-19 through Emergency visits in month of April–May 2020. Sociodemographic and clinical details were recorded from case file available in hospital record system. We compared this data with same period for previous year, that is, 2019. Results A total of 41 patients were admitted in the period of lockdown between April and May 2020, which is 37.8% less, compared to same period of last year. There was reduction in admission for patients with COPD (25.7% vs. 17.0%) and asthma (6% vs. 4.8%) compared to previous year but this difference was statistically not significant and this could be due to short period of evaluation which might not reflect the actual number of patients [Table 1]. There were more cases of lower respiratory tract infection/pneumonia and post-tuberculosis sequel that were admitted in lockdown period compared to previous year for same period. There were lesser deaths among admitted patient (4.87%) in 2019 as compared to 2020 (9.8%) for the same period. In 2019, out of the 6 patients who died, 2 were patients of lung cancer and 1 each was patient of sepsis, acute respiratory distress syndrome, chronic obstructive lung disease, and interstitial lung disease.Table 1: Comparison of respiratory emergencies in 2019 with 2020We infer that air pollution is a major public health hazard, particularly in developing countries and is associated with hospitalizations from respiratory diseases.[6] Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Spatial variation in lag structure in the short-term effects of air pollution on mortality in seven major South Korean cities, 2006–2013

Lag is one of the major uncertainties in the heterogeneity of short-term effects of particulate matter with aerodynamic diameter <10 μm (PM10) on mortality. This study aimed to explore spatial variations in extended lag effects of PM10 on all-cause mortality, cardiovascular mortality and respiratory mortality in seven major South Korean cities over a period spanning 2006–2013. We did time-series analysis using generalized linear models and adjusted for temporal trend, day of the week, holiday, influenza epidemic, and weather. Single lag models and distributed lag models were extensively compared, specifically in terms of lag interval, and adjustment for temporal trend. We also conducted a time-stratified case-crossover analysis. Multivariate meta-regressions with city characteristic variables were conducted in order to assess spatial variation in the lag structure. When considering up to previous 45 days of exposure, we found longer lag associations between PM10 and mortality, particularly in all-cause mortality and respiratory mortality. SO2, the ratio of SO2 to PM10 and gross regional domestic product were all found to positively contribute towards the associations between PM10 and all-cause mortality and cardiovascular mortality. Ulsan (Korea's largest industrial city) was found to have the strongest cumulative percentage increases in all-cause mortality and cardiovascular mortality per 10 μg/m3 increase of PM10: 4.9% (95% CI: 2.5, 7.3) and 4.3% (95% CI: −0.9, 9.7) respectively. Busan (Korea's largest seaport city) was found to have the highest cumulative percentage increase in respiratory mortality with an 8.2% increase (95% CI: 2.8, 13.8). In summary, the short-term effects of PM10 on mortality may persist over a period of not just few weeks but longer than a month, and may differ according to regional economy. This study provides public health implication that, in order to minimize the health effects of PM, air quality interventions should focus on not only particulate pollution but also gaseous pollution, such as SO2.

Short-term Effects of Ambient PM2.5 and PM2.5-10 on Mortality in Major Cities of Korea

ABSTRACT While many epidemiological studies have examined the health effects of different sizes of ambient particulate matter (PM), the findings have been mixed. PM is a heterogeneous mixture, and its chemical components differ by size, with more combustion related materials in the fine mode and more crustal materials in the coarse mode. This study estimates the risk of mortality associated with exposure to PM2.5 (particulate matter less than 2.5 µm in aerodynamic diameter) and PM2.5-10 (particulate matter less than 10 µm and greater than 2.5 µm in aerodynamic diameter). Long-term measurements of PM2.5 and PM2.5-10 were compared with the all-cause, cardiovascular, and respiratory mortality observed from January 2006 till December 2012 in three large cities in Korea (viz., Seoul, Busan, and Incheon). A time-series analysis based on a quasi-Poisson distribution was used to evaluate the associations of PM2.5 and PM2.5-10 with mortality. A 10 µg m−3 increase in PM2.5 (lag01) was associated with an increase of 1.18% (95% CI: 0.64, 1.72), 0.34% (95% CI: 0.03, 0.64), and 0.43% (90% CI: 0.02, 0.95) in the all-cause mortality in Busan, Seoul, and Incheon, respectively, during the study period. An increase in respiratory mortality of 0.52% (95% CI: 0.09, 0.96) and 2.25% (95% CI: 0.38, 4.15) was associated with a 10 µg m–3 increase in PM2.5 (lag01) in Seoul and Busan, respectively. Overall, the strongest associations were observed in Busan as well as among the elderly population. Statistically significant associations between ambient PM2.5 and PM2.5-10, and mortality were observed in this study. Exposure to fine particles, which mostly originate in combustion and mobile emissions, showed stronger effects on human health than coarse particles, which mostly originate in natural sources such as soil and mechanical processes.

Cardiorespiratory health effects of particulate ambient air pollution exposure in low-income and middle-income countries: a systematic review and meta-analysis

Most prospective studies on the health effects of particulate ambient air pollution exposure have focused on high-income countries, which have much lower pollutant concentrations than low-income and middle-income countries (LMICs) and different sources of pollution. We aimed to investigate the cardiorespiratory health effects of particulate ambient air pollution exposure in LMICs exclusively. For this systematic review and meta-analysis, we searched PubMed, Web of Science, Embase, LILACS, Global Health, and Proquest for studies published between database inception and Nov 28, 2016, investigating the cardiorespiratory health effects of particulate ambient air pollution exposure in LMICs. Data were extracted from published studies by one author, and then checked and verified by all authors independently. We pooled estimates by pollutant type (particulate matter with a diameter of <2·5 μm [PM2·5] or 2·5-10 μm [PM10]), lag, and outcome, and presented them as excess relative risk per 10 μg/m3 increase in particulate ambient air pollution. We used a random-effects model to derive overall excess risk. The study protocol is registered with PROSPERO, number CRD42016051733. Of 1553 studies identified, 91 met the full eligibility criteria. Only four long-term exposure studies from China were identified and not included in the meta-analysis. A 10 μg/m3 increase in same-day PM2·5 was associated with a 0·47% (95% CI 0·34-0·61) increase in cardiovascular mortality and a 0·57% (0·28-0·86) increase in respiratory mortality. A 10 μg/m3 increase in same-day PM10 was associated with a 0·27% (0·11-0·44) increase in cardiovascular mortality and a 0·56% (0·24-0·87) increase in respiratory mortality. Short-term exposure to particulate ambient air pollution is associated with increases in cardiorespiratory morbidity and mortality in LMIC's, with apparent regional-specific variations. None.

The Short-Term Effects of Visibility and Haze on Mortality in a Coastal City of China: A Time-Series Study.

Few studies have been conducted to investigate the acute health effects of visibility and haze, which may be regarded as proxy indicators of ambient air pollution. We used a distributed lag non-linear model (DLNM) combined with quasi-Poisson regression to estimate the relationship between visibility, haze and mortality in Ningbo, a coastal city of China. We found that the mortality risk of visibility was statistically significant only on the current day, while the risk of haze and PM10 peaked on the second day and could last for three days. When the visibility was less than 10 km, each 1 km decrease of visibility at lag 0 day was associated with a 0.78% (95% CI: 0.22–1.36%) increase in total mortality and a 1.61% (95% CI: 0.39–2.85%) increase in respiratory mortality. The excess risk of haze at lag 0–2 days on total mortality, cardiovascular and respiratory mortality was 7.76% (95% CI: 3.29–12.42%), 7.73% (95% CI: 0.12–15.92%) and 17.77% (95% CI: 7.64–28.86%), respectively. Greater effects of air pollution were observed during the cold season than in the warm season, and the elderly were at higher risk compared to youths. The effects of visibility and haze were attenuated by single pollutants. These findings suggest that visibility and haze could be used as surrogates of air quality where pollutant data are scarce, and strengthen the evidence to develop policy to control air pollution and protect vulnerable populations.

Seasonal association between ambient ozone and mortality in Zhengzhou, China.

Different seasonal health effects of ambient ozone (O3) have been reported in previous studies. This might be due to inappropriate adjustment of temperature in different seasons. We used daily data on non-accidental mortality and ambient air pollution in Zhengzhou from January 19, 2013 to June 30, 2015. Season-stratified analyses using generalized additive models were conducted to evaluate the seasonal associations with adjustment of temperature with different lagged days (lag0-1 for warm season, lag0-14 for cold season). We recorded a total of 70,443 non-accidental deaths in Zhengzhou during the study period. Significant associations were observed between ambient O3 and mortality in cold season. Every 10-μg/m3 increment of 24-h O3 of 1-day lagged time was associated with a 1.38% (95% CI 0.60, 2.16%) increase in all cause mortality, 1.35% (95% CI 0.41, 2.30%) increase in cardiovascular mortality, and 1.78% (95% CI 0.43, 3.14%) increase in respiratory mortality. Similar associations were observed when using daily 1- and 8-h maximum concentrations of O3. No significant association was found during warm season. This study suggests a more pronounced ozone-mortality association in cold season in Zhengzhou, and we suggest that different lagged temperatures should be considered when examining the seasonal health effects of ambient ozone.

The Short-Term Effect of Ambient Temperature on Mortality in Wuhan, China: A Time-Series Study Using a Distributed Lag Non-Linear Model.

Less evidence concerning the association between ambient temperature and mortality is available in developing countries/regions, especially inland areas of China, and few previous studies have compared the predictive ability of different temperature indictors (minimum, mean, and maximum temperature) on mortality. We assessed the effects of temperature on daily mortality from 2003 to 2010 in Jiang’an District of Wuhan, the largest city in central China. Quasi-Poisson generalized linear models combined with both non-threshold and double-threshold distributed lag non-linear models (DLNM) were used to examine the associations between different temperature indictors and cause-specific mortality. We found a U-shaped relationship between temperature and mortality in Wuhan. Double-threshold DLNM with mean temperature performed best in predicting temperature-mortality relationship. Cold effect was delayed, whereas hot effect was acute, both of which lasted for several days. For cold effects over lag 0–21 days, a 1 °C decrease in mean temperature below the cold thresholds was associated with a 2.39% (95% CI: 1.71, 3.08) increase in non-accidental mortality, 3.65% (95% CI: 2.62, 4.69) increase in cardiovascular mortality, 3.87% (95% CI: 1.57, 6.22) increase in respiratory mortality, 3.13% (95% CI: 1.88, 4.38) increase in stroke mortality, and 21.57% (95% CI: 12.59, 31.26) increase in ischemic heart disease (IHD) mortality. For hot effects over lag 0–7 days, a 1 °C increase in mean temperature above the hot thresholds was associated with a 25.18% (95% CI: 18.74, 31.96) increase in non-accidental mortality, 34.10% (95% CI: 25.63, 43.16) increase in cardiovascular mortality, 24.27% (95% CI: 7.55, 43.59) increase in respiratory mortality, 59.1% (95% CI: 41.81, 78.5) increase in stroke mortality, and 17.00% (95% CI: 7.91, 26.87) increase in IHD mortality. This study suggested that both low and high temperature were associated with increased mortality in Wuhan, and that mean temperature had better predictive ability than minimum and maximum temperature in the association between temperature and mortality.