Non-accidental Deaths Research Articles

Future temperature-related excess mortality under climate change and population aging scenarios in Canada

ObjectiveClimate change is expected to increase global temperatures. How temperature-related mortality risk will change is not completely understood, and how future demographic changes will affect temperature-related mortality needs to be clarified. We evaluate temperature-related mortality across Canada until 2099, accounting for age groups and scenarios of population growth.MethodsWe used daily counts of non-accidental mortality for 2000 to 2015 for all 111 health regions across Canada, incorporating in the study both urban and rural areas. A two-part time series analysis was used to estimate associations between mean daily temperatures and mortality. First, current and future daily mean temperature time series simulations were developed from Coupled Model Inter-Comparison Project 6 (CMIP6) climate model ensembles from past and projected climate change scenarios under Shared Socioeconomic Pathways (SSPs). Next, excess mortality due to heat and cold and the net difference were projected to 2099, also accounting for different regional and population aging scenarios.ResultsFor 2000 to 2015, we identified 3,343,311 non-accidental deaths. On average, a net increase of 17.31% (95% eCI: 13.99, 20.62) in temperature-related excess mortality under a higher greenhouse gas emission scenario is expected for Canada in 2090–2099, which represents a greater burden than a scenario that assumed strong levels of greenhouse gas mitigation policies (net increase of 3.29%; 95% eCI: 1.41, 5.17). The highest net increase was observed among people aged 65 and over, and the largest increases in both net and heat- and cold-related mortality were observed in population scenarios that incorporated the highest rates of aging.ConclusionCanada may expect net increases in temperature-related mortality under a higher emissions climate change scenario, compared to one assuming sustainable development. Urgent action is needed to mitigate future climate change impacts.

A longitudinal study on the effect of extreme temperature on non-accidental deaths in Hulunbuir City based on DLNM model

ObjectiveTo explore the frequency and effect of extreme temperature on the non-accidental death rate in Hulunbuir, a Chinese ice city.MethodsFrom 2014 to 2018, mortality data of residents residing in Hulunbuir City were collected. The lag and cumulative effects of extreme temperature conditions on non-accidental death and respiratory and circulatory diseases were analyzed by distributed lag non-linear models (DLNM).ResultsThe risk of death was the highest during high-temperature conditions, the RR value was 1.111 (95% CI 1.031 ~ 1.198). The effect was severe and acute. The risk of death during extreme low-temperature conditions peaked on the fifth day, (RR 1.057; 95% CI 1.012 ~ 1.112), then decreased and was maintained for 12 days. The cumulative RR value was 1.289 (95% CI 1.045 ~ 1.589). Heat significantly influenced the incidence of non-accidental death in both men (RR 1.187; 95% CI 1.059–1.331) and women (RR 1.252; 95% CI 1.085–1.445).ConclusionsRegardless of the temperature effect, the risk of death in the elderly group (≥ 65 years) was significantly higher than that of the young group (0–64 years). High-temperature and low-temperature conditions can contribute to the increased number of deaths in Hulunbei. While high-temperature has an acute effect, low-temperature has a lagging effect. Elderly and women, as well as people with circulatory diseases, are more sensitive to extreme temperatures.

Precision Public Health Opportunity: Heat-Associated Mortality Greater among Pilgrims during Hajj

Precision Public Health Opportunity: Heat-Associated Mortality Greater among Pilgrims during Hajj

Mortality burden due to ambient nitrogen dioxide pollution in China: Application of high-resolution models

BackgroundA large gap exists between the latest Global Air Quality Guidelines (AQG 2021) and Chinese air quality standards for NO2. Assessing whether and to what extent air quality standards for NO2 should be tightened in China requires a comprehensive understanding of the spatiotemporal characteristics of population exposure to ambient NO2 and related health risks, which have not been studied to date. ObjectiveWe predicted ground NO2 concentrations with high resolution in mainland China, explored exposure characteristics to NO2 pollution, and assessed the mortality burden attributable to NO2 exposure. MethodsDaily NO2 concentrations in 2019 were predicted at 1-km spatial resolution in mainland China using random forest models incorporating multiple predictors. From these high-resolution predictions, we explored the spatiotemporal distribution of NO2, population and area percentages with NO2 exposure exceeding criterion levels, and premature deaths attributable to long- and short-term NO2 exposure in China. ResultsThe cross-validation R2and root mean squared error of the NO2 predicting model were 0.80 and 7.78 μg/m3, respectively,at the daily level in 2019.The percentage of people (population number) with annual NO2 exposure over 40 μg/m3 in mainland China in 2019 was 10.40 % (145,605,200), and it reached 99.68 % (1,395,569,840) with the AQG guideline value of 10 μg/m3. NO2 levels and population exposure risk were elevated in urban areas than in rural. Long- and short-term exposures to NO2 were associated with 285,036 and 121,263 non-accidental deaths, respectively, in China in 2019. Tightening standards in steps gradually would increase the potential health benefit. ConclusionIn China, NO2 pollution is associated with significant mortality burden. Spatial disparities exist in NO2 pollution and exposure risks. China’s current air quality standards may no longer objectively reflect the severity of NO2 pollution and exposure risk. Tightening the national standards for NO2 is needed and will lead to significant health benefits.

Human tolerance to extreme heat: evidence from a desert climate population.

Ambient temperatures exceeding 40 °C are projected to become common in many temperate climatic zones due to global warming. Therefore, understanding the health effects of continuous exposure to high ambient temperatures on populations living in hot climatic regions can help identify the limits of human tolerance. We studied the relationship between ambient temperature and non-accidental mortality in the hot desert city of Mecca, Saudi Arabia, between 2006 and 2015. We used a distributed lag nonlinear model to estimate the mortality-temperature association over 25 days of lag. We determined the minimum mortality temperature (MMT) and the deaths that are attributable to heat and cold. We analyzed 37,178 non-accidental deaths reported in the ten-year study period among Mecca residents. The median average daily temperature was 32 °C (19-42 °C) during the same study period. We observed a U-shaped relationship between daily temperature and mortality with an MMT of 31.8 °C. The total temperature-attributable mortality of Mecca residents was 6.9% (-3.2; 14.8) without reaching statistical significance. However, extreme heat, higher than 38 °C, was significantly associated with increased risk of mortality. The lag structure effect of the temperature showed an immediate impact, followed by a decline in mortality over many days of heat. No effect of cold on mortality was observed. High ambient temperatures are projected to become future norms in temperate climates. Studying populations familiar with desert climates for generations with access to air-conditioning would inform on the mitigation measures to protect other populations from heat and on the limits of human tolerance to extreme temperatures. We studied the relationship between ambient temperature and all-cause mortality in the hot desert city of Mecca. We found that Mecca population is adapted to high temperatures, although there was a limit to tolerance to extreme heat. This implies that mitigation measures should be directed to accelerate individual adaptation to heat and societal reorganization.

Death of parent, sibling, spouse, and child in a Swedish national sample and risk of subsequent stress reaction, major depression, alcohol-use disorder, and drug-use disorder.

To determine, in a general population, how much rates of stress reactions (SR), major depression (MD), alcohol-use disorder (AUD) and drug-use disorder (DUD) increase after the death of close relatives. SR, MD, AUD, and DUD registrations were assessed from national Swedish registries. From the population followed from 2000 to 2018, those exposed to death of a close relative in 2002-2016 were matched to unexposed controls and analyzed in males and females by a controlled pre-post design using a difference-in-difference method. Substantial, brief increases in risk for SR and more modest prolonged increases in MD were observed after death of relatives in both men and women greatest with children, followed by spouses, parents, and siblings. Relatively long-lasting modest increases in AUD but not DUD were also observed following death of relatives. The absolute increases for SR and MD were greater in females than males and for AUD greater in males than females. However, logistic regression analyses showed most effects did not differ significantly by sex. Consistently larger increases in disorder risk were seen with the death of younger v. older parents, siblings, and spouses and with accidental v. non-accidental death in children. Applying a matched cohort design to Swedish population registries, death of close relatives was associated with, and likely caused, substantial increases in rates of SR, MD, and AUD, consistent with smaller prior clinical investigations. Through such registries, we can, in large representative samples, integrate the impact of exposures to selected environmental adversities into disorder risk pathways.

Association of Ambient Temperature with Mortality in Resident and Multiethnic Transient Populations in a Desert Climate, 2006–2014

Although the association between ambient temperature and mortality in local populations is evident, this relationship remains unclear in transient populations (e.g., due to immigration, mass gatherings, or displacement). The holy city of Mecca annually shelters two populations comprising its residents and the transitory Hajj pilgrims ( people from countries). Both live side by side in a hot desert climate, rendering the development of evidence-based heat-protective measures challenging. We aimed to characterize the ambient temperature-mortality relationship and burden for the Mecca resident and Hajj transient populations, which have distinct levels of adaptation to ambient temperature. We analyzed daily air temperature and mortality data for Mecca residents and pilgrims over nine Hajj seasons between 2006 and 2014, using a fitted standard time-series Poisson model. We characterized the temperature-mortality relationship with a distributed lag nonlinear model with 10 d of lag. We determined the minimum mortality temperature (MMT) and attributable deaths for heat and cold for the two populations. The median average daily temperature during the Hajj seasons was 30°C (19°C-37°C). There were 8,543 and 10,457 nonaccidental deaths reported during the study period among Mecca residents and pilgrims, respectively. The MMT was 2.5°C lower for pilgrims in comparison with the MMT for Mecca residents (23.5°C vs. 26.0°C). The temperature-mortality relationship shape varied from inverted J to U shape for the Mecca and pilgrim populations, respectively. Neither hot nor cold temperatures had a statistically significant association with mortality in Mecca residents. In contrast, for pilgrims, elevated temperatures were associated with significantly high attributable mortality of 70.8% [95% confidence interval (CI): 62.8, 76.0]. The effect of heat on pilgrims was immediate and sustained. Our findings indicate that pilgrims and Mecca residents exposed to the same hot environmental conditions exhibited distinct health outcomes. This conclusion suggests that a precision public health approach may be warranted to protect against high environmental temperature during mass gatherings of diverse populations. https://doi.org/10.1289/EHP9838.

The impact of heat waves on the mortality of Chinese population: A systematic review and meta-analysis.

Many studies had shown that with global warming, heat waves may increase the mortality risk of Chinese populations. However, these findings are not consistent. Therefore, we elucidated the associations by meta-analysis and quantified the magnitude of these risks, as well as the underlying factors. We searched the China National Knowledge Infrastructure (CNKI), Wanfang database, PubMed, EMBASE, and Web of Science for literature screening up to Nov 10, 2022, to analyze the effect of heat waves on mortality in the Chinese population. Literature screening and data extraction were performed independently by two researchers and the data were merged by meta-analysis. In addition, we conducted subgroup analysis by sex, age, years of education, region, and number of events to explore the source of heterogeneity. Fifteen related studies on the impact on heat waves of the death of Chinese people were included in this study. The results of the meta-analysis showed that heat waves were significantly associated with increased mortality from non-accidental deaths, cardiovascular diseases, stroke, respiratory diseases, and circulatory diseases in the Chinese population: non-accidental mortality (RR = 1.19, 95% CI: 1.13-1.27, P < .01), cardiovascular diseases (RR = 1.25, 95% CI: 1.14-1.38), stroke (RR = 1.11, 95% CI: 1.03-1.20), respiratory diseases (RR = 1.18, 95% CI: 1.09-1.28), and circulatory diseases (RR = 1.11, 95% CI: 1.06-1.17). Subgroup analyses showed that heat waves had a higher risk of non-accidental death for those with <6 years of education than for those with ≥6 years of education. Meta-regression analysis showed that the contribution of the study year to the inter studied heterogeneity was 50.57%. The sensitivity analysis showed that the exclusion of any single study did not materially alter the overall combined effect. The meta-analysis method indicated no obvious evidence of publication bias. The results of the review indicated that heat waves were associated with increased mortality in the Chinese population, that attention should be paid to high-risk groups, and that public health policies and strategies should be implemented to more effectively respond to and adapt to climate change.

Using Parametric g-Computation to Estimate the Effect of Long-Term Exposure to Air Pollution on Mortality Risk and Simulate the Benefits of Hypothetical Policies: The Canadian Community Health Survey Cohort (2005 to 2015).

Numerous epidemiological studies have documented the adverse health impact of long-term exposure to fine particulate matter [particulate matter in aerodynamic diameter ()] on mortality even at relatively low levels. However, methodological challenges remain to consider potential regulatory intervention's complexity and provide actionable evidence on the predicted benefits of interventions. We propose the parametric g-computation as an alternative analytical approach to such challenges. We applied the parametric g-computation to estimate the cumulative risks of nonaccidental death under different hypothetical intervention strategies targeting long-term exposure to in the Canadian Community Health Survey cohort from 2005 to 2015. On both relative and absolute scales, we explored the benefits of hypothetical intervention strategies compared with the natural course that a) set the simulated exposure value at each follow-up year to a threshold value if exposure was above the threshold (, , , and ), and b) reduced the simulated exposure value by a percentage (5% and 10%) at each follow-up year. We used the 3-y average concentration with 1-y lag at the postal code of respondents' annual mailing addresses as their long-term exposure to . We considered baseline and time-varying confounders, including demographics, behavior characteristics, income level, and neighborhood socioeconomic status. We also included the R syntax for reproducibility and replication. All hypothetical intervention strategies explored led to lower 11-y cumulative mortality risks than the estimated value under the natural course without intervention, with the smallest reduction of 0.20 per 1,000 participants (95% CI: 0.06, 0.34) under the threshold of , and the largest reduction of 3.40 per 1,000 participants (95% CI: , 7.03) under the relative reduction of 10% per interval. The reductions in cumulative risk, or numbers of deaths that would have been prevented if the intervention was employed instead of maintaining the status quo, increased over time but flattened toward the end of the follow-up period. Estimates among those years of age were greater with a similar pattern. Our estimates were robust to different model specifications. We found evidence that any intervention further reducing the long-term exposure to would reduce the cumulative mortality risk, with greater benefits in the older population, even in a population already exposed to low levels of ambient . The parametric g-computation used in this study provides flexibilities in simulating real-world interventions, accommodates time-varying exposure and confounders, and estimates adjusted survival curves with clearer interpretation and more information than a single hazard ratio, making it a valuable analytical alternative in air pollution epidemiological research. https://doi.org/10.1289/EHP11095.

Short-term effects of PM10 on cause-specific mortality and the role of long-term environmental pressures in the industrial areas of Brindisi and Civitavecchia

the health status of people living near industrial plants is often exposed to several environmental risk factors, including air pollution. The aim of this study is to assess the relationship between daily PM10 levels and cause-specific mortality in a selection of municipalities near two industrial plants from 2006 to 2015. a time-series design with Poisson regression adjusted for a predefined set of confounders was used to quantify the association between exposure, calculated as daily PM10 levels extrapolated from machine-learning models using satellite data, and cause-specific mortality. twenty municipalities near the thermal power plants in Civitavecchia and Brindisi were selected. The municipalities were then divided into three scenarios of chronic exposure derived from SPRAY simulation models of pollutant deposition. daily cause-specific non-accidental, cardiovascular, and respiratory deaths defined according to the International Classification of Diseases code at the municipality level. a total of 41,942 deaths were observed in the entire area (10,503 in the Civitavecchia area and 31,439 in the Brindisi area), of which approximately 41% were due to cardiovascular causes and 8% due to respiratory causes. The association showed an increase in shortterm effects in municipalities with higher chronic levels of pollution exposure. For example, risk estimates reported as percentage increases per 10-unit increase in PM10 were 6.7% (95% CI 0.9, 12.7%) in scenario 3 (highest exposure) compared to 4.2% (-1.2, 9.9%) and 2.7% (-4.2, 10.2%) in scenarios 2 and 1, respectively, in the area near the Civitavecchia plant. Similar effects were observed for the Brindisi area. despite the well-documented relationship between short-term pollution and mortality, it appears that greater chronic exposure to industrial pollutants leads to increased short-term effects of PM10. The limited number of events suggests that this study could serve as a starting point for a larger investigation.

Driving factors behind the continuous increase of long-term PM2.5-attributable health burden in India using the high-resolution global datasets from 2001 to 2020

Air pollution is the fourth leading global risk factor, whereas in India air pollution is reported as the highest risk factor with millions of premature deaths every year. Despite implementation of several air pollution control plans, PM2.5 levels over India have not noticeably reduced. PM2.5-associated health burdens in India have increased significantly in past decades. A fine resolution (0·01° × 0·01°) analysis of PM2.5-attribulable premature deaths (rather than the coarse-level analysis) may elucidate the reason for this increase and inform and effective start-of-the-art state-level and national emission control strategies. This study quantified the spatiotemporal dynamics of PM2.5-attributable premature deaths from 2001 to 2020 and applied a decomposition analysis to dissect the contribution of various associated parameters, such as PM2.5 concentration, population distribution and disease-specific baseline death rate. Results show significant spatiotemporal variations of PM2.5 and associated health burden in India. During the study period, population weighted PM2.5 value increased from 46.0 to 59.5 μg/m3 and associated non-communicable death increased around 87.6 %, from 1050 [95 % (CI): 880–1210] thousand to 1970 (95 % CI: 1658-2259) thousand. The states of Uttar Pradesh, Bihar, West Bengal, Maharashtra, Rajasthan, and Madhya Pradesh had the highest PM2.5-attributable deaths. In these states, non-accidental deaths increased from 232.1, 112.7, 81.4, 79.1, 66.3 and 58.5 thousand in 2001 to 424.1, 226.7, 156.2, 154.5, 123.3 and 119.7 thousand in 2020. In per capita population (/105 population), the highest PM2.5-attributable deaths were observed in Delhi, Uttar Pradesh, Bihar, Haryana and Punjab. Throughout the study period, demographic changes outweighed the health burden and were responsible for ~62.8 % increase of PM2.5-related non-accidental deaths across India, whereas the change in PM2.5 concentration influenced only 18.7 %. The change in baseline mortality rate impacts differently for the estimation of disease-specific mortality changes. Our findings suggest more dynamic and comprehensive policies at state-specific level, especially for North India is very indispensable for the overall decrease of PM2.5-related deaths in India.

A satellite-driven model to estimate long-term particulate sulfate levels and attributable mortality burden in China

Ambient fine particulate matter (PM2.5) pollution is a major environmental and public health challenge in China. In the recent decade, the PM2.5 level has decreased mainly driven by reductions in particulate sulfate as a result of large-scale desulfurization efforts in coal-fired power plants and industrial facilities. Emerging evidence also points to the differential toxicity of particulate sulfate affecting human health. However, estimating the long-term spatiotemporal trend of sulfate is difficult because a ground monitoring network of PM2.5 constituents has not been established in China. Spaceborne sensors such as the Multi-angle Imaging SpectroRadiometer (MISR) instrument can provide complementary information on aerosol size and type. With the help of state-of-the-art machine learning techniques, we developed a sulfate prediction model under support from available ground measurements, MISR-retrieved aerosol microphysical properties, and atmospheric reanalysis data at a spatial resolution of 0.1°. Our sulfate model performed well with an out-of-bag cross-validationR2 of 0.68 at the daily level and 0.93 at the monthly level. We found that the national mean population-weighted sulfate concentration was relatively stable before the Air Pollution Prevention and Control Action Plan was enforced in 2013, ranging from 10.4 to 11.5 µg m−3. But the sulfate level dramatically decreased to 7.7 µg m−3 in 2018, with a change rate of −28.7 % from 2013 to 2018. Correspondingly, the annual mean total non-accidental and cardiopulmonary deaths attributed to sulfate decreased by 40.7 % and 42.3 %, respectively. The long-term, full-coverage sulfate level estimates will support future studies on evaluating air quality policies and understanding the adverse health effect of particulate sulfate.

Investigating paediatric sarcoma management worldwide: a study protocol

AbstractIntroductionCancer is the leading cause of non-accidental death among children worldwide. The most common types of paediatric cancers include sarcomas: a group of cancers that are difficult to manage due to their heterogeneity and lack of defining features. We have designed an international multicentre cohort study to assess the management of paediatric sarcomas at tertiary healthcare centres in Nigeria, Pakistan and the UK.Methods and AnalysisThe centres will screen patient databases to identify eligible patients under the age of 18 with a clinical or histological diagnosis of sarcoma. Data will be extracted from the patient notes through an anonymized form. Patients will be recruited consecutively into the study from January 2015 to January 2021, with a minimum 12-month follow up period. The primary objectives of the study will be to determine all-cause mortality rates at 30 days, 90 days, 12 months and 3 years. Significant differences in mortality rates between countries will be determined using χ2 analysis or Fisher’s exact test. Univariate and multivariable logistic regression will be used to examine the influence of different factors and patient characteristics on outcomes.Ethics and DisseminationAt the host centre, this study was deemed to be exempt from ethical committee approval due to the use of anonymized data. At other centres, participating collaborators have gained local approvals in accordance with institutional ethical regulations. Collaborators will present the data to inform decision makers about how sarcoma management may be improved. The results will be submitted for publication in a peer-reviewed journal.

Mortality Risk Related to Heatwaves in Dezful City, Southwest of Iran.

We aimed to evaluate the impact of heatwaves on daily deaths due to non-accidental, cardiovascular and respiratory causes in the city of Dezful in Iran from 2013 to 2019. We collected daily ambient temperature and mortality and defined 2 types of heatwaves by combining daily temperature ⩾90th in each month of the study period or since 30 years with duration ⩾2 and 3 days. We used a distributed lag non-linear model to study the association between each type of heatwave definition, and deaths due to non-accidental, cardiovascular and respiratory causes with lags up to 13 days. There was no discernible correlation in this area, despite the fact that heatwaves raised the risk of death from cardiovascular causes and lowered the risk from respiratory causes. On the other hand, the risk of total non-accidental mortality on days with the heatwaves is significantly higher than normal days. In main effects, the heatwaves have a significant relationship with the risk of total non-accidental mortality (in the first heatwave definition, Cumulative Excess Risk (CER) in lag0-2 was 10.4 and in second heatwave definition, CER values in lag0, 0-2, and 0-6 were 12.4, 29.2, and 38.8 respectively). Also, in added effects, heatwaves have a significant relationship with the risk of total non-accidental mortality (in the first heatwave definition, CER in lag0 and 0-2 were 1.79 and 4.11 and in the second heatwave definition, CER values in lag0, 0-2, and 0-6 were 7.76, 18.35 and 24.87 respectively). In addition, heatwaves appeared to contribute to a cumulative excess risk of non-accidental death among the male group as well as the older adults. However, the results showed that heatwaves could have detrimental effects on health, even in populations accustomed to the extreme heat. Therefore, early warning systems which monitor heatwaves should provide the necessary warnings to the population, especially the most vulnerable groups.

Effects of sulfur dioxide inhalation on human health: a review.

Sulfur dioxide (SO2) is one of the most important gaseous air pollutants and the chemical index of sulfur oxides (SOx). SO2 is one of the six criteria pollutants in the air quality index (AQI). SO2 can be emitted by natural and anthropogenic sources. Although efforts have been made to reduce sulfur dioxide emissions worldwide, this pollutant and its adverse effects remain a major concern, especially in developing countries. The aim of this study was the investigated the effects of sulfur dioxide inhalation on human health. This narrative review was done based on the literature published from 2000 to 2022 through PubMed, Springer, Web of Science, Science Direct, and Google Scholar databases. In this study, was done screened first based on the abstract and Final assessment done based on the full text of the article. Finally, 38 articles were selected for inclusion in the study. The results of this study showed that sulfur dioxide has adverse health effects on the human respiratory, cardiovascular, and nervous systems and causes type 2 diabetes and non-accidental deaths. Although some evidence suggests that sulfur dioxide in given concentrations has no adverse health effect, its synergistic effects in combination with other air pollutants may be significant. Among the most important practical results of this study can be mentioned to increase the health awareness of the general public, help the politicians of the health sector in making decisions in the health field, creating awareness among polluting producing units and industries and efforts to reduce the emission of Sulfur dioxide.

The effects of short-term exposure to air pollution on mortality in Baotou, China, during 2015-2019.

Air pollution was considered one of the main causes linked to increased morbidity and mortality around the world. This study aimed to estimate the effect of air pollutants on daily death in Baotou city of Inner Mongolia. Daily deaths data were provided by Baotou Centers for Disease Control and Prevention for the years 2015-2019 (Baotou CDC). The air pollutants, PM2.5, PM10, NO2, SO2, CO and maximum 8-h average concentrations of O3, came from the eight environmental monitoring stations in Baotou city. Time-series plots were used to exploit the trend of air pollutants at calendar time. Generalized additive model was used to estimate the effect of air pollutants on daily death. Restricted cubic spline was employed to investigate non-line relationships between air pollutants and daily death. After adjusting the meteorological factors, non-accidental daily deaths were related to PM2.5 (ER = 0.074%) and PM10 (ER = 0.023%), respectively. In stratified analysis, population aged over 65years and females were more sensitive to air pollutants exposure and warm season might make people more susceptible to air pollutants compared with cold season. PM2.5 and PM10 increase the risk of non-accidental and cardiovascular daily death, but not respiratory daily death.

Short term exposure to air pollution and mortality in the US: a double negative control analysis

RationaleStudies examining the association of short-term air pollution exposure and daily deaths have typically been limited to cities and used citywide average exposures, with few using causal models.ObjectivesTo estimate the associations between short-term exposures to fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) and all-cause and cause-specific mortality in multiple US states using census tract or address exposure and including rural areas, using a double negative control analysis.MethodsWe conducted a time-stratified case-crossover study examining the entire population of seven US states from 2000–2015, with over 3 million non-accidental deaths. Daily predictions of PM2.5, O3, and NO2 at 1x1 km grid cells were linked to mortality based on census track or residential address. For each pollutant, we used conditional logistic regression to quantify the association between exposure and the relative risk of mortality conditioning on meteorological variables, other pollutants, and using double negative controls.ResultsA 10 μg/m3 increase in PM2.5 exposure at the moving average of lag 0–2 day was significantly associated with a 0.67% (95%CI: 0.34–1.01%) increase in all-cause mortality. 10 ppb increases in NO2 or O3 exposure at lag 0–2 day were marginally associated with and 0.19% (95%CI: −0.01-0.38%) and 0.20 (95% CI-0.01, 0.40), respectively. The adverse effects of PM2.5 persisted when pollution levels were restricted to below the current global air pollution standards. Negative control models indicated little likelihood of omitted confounders for PM2.5, and mixed results for the gases. PM2.5 was also significantly associated with respiratory mortality and cardiovascular mortality.ConclusionsShort-term exposure to PM2.5 and possibly O3 and NO2 are associated with increased risks for all-cause mortality. Our findings delivered evidence that risks of death persisted at levels below currently permissible.

Associations of climate variability driven by El Niño-southern oscillation with excess mortality and related medical costs in Chinese elderly

Climate variability driven by El Niño-Southern Oscillation (ENSO) is a significant public health concern in parallel with global population aging; however, its role in healthy aging is less studied. We examined the longitudinal impacts of ENSO exposure on excess mortality and related medical costs in the elderly from 23 provinces of China. A total of 27,533 non-accidental all-cause deaths were recorded in 30,763 participants during 1998–2018. We found that both low and high levels of ENSO metrics over lags of 0–12 months were associated with increased mortality risks. Specifically, comparing the 10th percentile (−1.8) and 90th percentile (2.0) multivariate El Niño index (MEI) levels to the reference level with the minimum effect of MEI exposure, the risk of mortality was 1.87 (95 % confidence interval [CI], 1.75, 2.00) and 4.89 (95 % CI, 4.36, 5.49), respectively. ENSO exposure was also positively related to medical costs. Further, the associations were stronger among drinkers, lower-income participants, and those with higher blood pressure and heart rate measured at the most recent follow-ups. Our results suggested that ENSO exposure was capable of heightening mortality risks and medical burden among older elderly adults, highlighting that climate variability driven by ENSO could be a crucial determinant of healthy aging.

Health benefits by attaining the new WHO air quality guideline targets in China: A nationwide analysis

To reduce the high disease burden caused by air pollution, World Health Organization (WHO) issued a new air quality guideline (AQG) on the 22nd September 2021. A timely quantitative assessment of health benefits by meeting these targets is a key measure to advocate and inform national and regional disease control policies. We collected daily major air pollution data in 315 Chinese cities from the 1st January to the 31st December 2019, and the corresponding annual population and mortality rate in the whole population of each city. Then, the mortality benefits were estimated when daily air pollution levels attained WHO's new AQG targets (15 μg/m3 for PM2.5, 25 μg/m3 for NO2 and 100 μg/m3 for O3) in 315 Chinese cities and 31 provinces by using pollutant- and cause-specific concentration-response functions. In total, 134,025 (95%CI: 92,768; 173,029) air pollution-associated non-accidental deaths could be avoided in 315 Chinese cities in 2019 by attaining WHO's new AQG targets, with 43,800 (95%CI: 29,945; 55,616) avoidable deaths from PM2.5, 58,070 (95%CI: 45,333; 70,714) from NO2, and 32,155 (95%CI: 17,490; 46,699) from O3. Cardiovascular diseases and respiratory diseases accounted for 72,698 (95%CI: 46,561; 101,680) and 17,726 (95%CI: 8603; 26,925) avoidable deaths, respectively. Health benefits from reduction in air pollution levels were 99.26 avoided non-accidental deaths per million population at national level, ranging from 12.48 per million in Tibet to 166.26 per million in Hebei. These findings suggest that the compliance with the WHO updated AQG standards would save substantial amount of air pollution-related premature deaths in China. More stringent air pollution control and management measures are urgently warranted to reduce the disease burden from air pollutants in China, particularly for the worsening O3 pollution.

Short-term exposure to fine particulate matter constituents and mortality: case-crossover evidence from 32 counties in China.

A growing number of studies associated increased mortality with exposures to specific fine particulate (PM2.5) constituents, while great heterogeneity exists between locations. In China, evidence linking PM2.5 constituents and mortality was extensively sparse. This study primarily aimed to quantify short-term associations between PM2.5 constituents and non-accidental mortality among the Chinese population. We collected daily mortality records from 32 counties in China between January 1, 2011, and December 31, 2013. Daily concentrations of main PM2.5 constituents (organic carbon (OC), elemental carbon (EC), nitrate (NO3-), sulfate (SO42-), and ammonium (NH4+)) were estimated using the modified Community Multiscale Air Quality model. Time-stratified case-crossover design with conditional logistic regression models was adopted to estimate mortality risks associated with short-term exposures to PM2.5 mass and its constituents. Stratification analyses were done by sex, age, and season. A total of 116,959 non-accidental deaths were investigated. PM2.5 concentrations on the day of death were averaged at 75.7 µg m-3 (control day: 75.6 µg m-3), with an interquartile range (IQR) of 65.2 µg m-3. Per IQR rise in PM2.5, EC, OC, NO3-, SO42-, and NH4+ at lag-04 day was associated with an increase in non-accidental mortality of 2.4% (95% confidence interval, (1.0-3.7), 1.7% (0.8-2.7), 2.9% (1.6-4.3), 2.1% (0.4-3.9), 1.0% (0.2-1.9), and 1.6% (0.3-2.9), respectively. Both PM2.5 mass and its constituents were strongly associated with elevated cardiovascular mortality risks, but only PM2.5, EC, and OC were positively associated with respiratory mortality at lag-3 day. PM2.5 mass and its constituents associated effects on mortality varied among sex- and age-specific subpopulations. Differences in the seasonal pattern of associations exist among PM2.5 constituents, with stronger effects related to EC and NO3- in warm months but SO42- and NH4+ in cold months. Short-term exposures to PM2.5 compositions were positively associated with increased risks of mortality, particularly those constituents from combustion-related sources.