Short-term effects of outdoor air pollution on acute ischaemic stroke occurrence: a case-crossover study in Tianjin, China

Bidirectional modification effects on nonlinear associations of summer temperature and air pollution with first-ever stroke morbidity

High temperature and air pollution may induce stroke morbidity. However, whether associations between high temperature and air pollution with stroke morbidity are modified by each other is still unclear. Data on 23,578 first-ever stroke patients in Shenzhen, China, during the summers of 2014-2018 were collected. Distributed lag nonlinear models were used to assess the modifying effects of air pollution stratified by the median for the associations between summer temperature and stroke morbidity at 0-3 lag days; modifying effects of temperature stratified by the minimum morbidity temperature on the associations between air pollution and stroke morbidity at the same lags were also estimated. The attributable risks of high temperature and high pollution on stroke morbidity were quantified. Stratified analyses of gender, age, migration type, and complication type were conducted to assess vulnerable population characteristics. Summer high temperature may induce stroke morbidity at high-level PM2.5, PM10, O3, SO2, and NO2 conditions, with attributable fraction (AF) of 2.982% (95% empirical confidence interval [eCI]: 0.943, 4.929), 3.113% (0.948, 5.200), 2.841% (0.943, 4.620), 3.617% (1.539, 5.470), and 2.048% (0.279, 3.637), respectively. High-temperature effects were statistically insignificant at corresponding low-level air pollution conditions. High-level PM2.5, PM10, and O3 may induce stroke morbidity at high-temperature conditions, with AF of 3.664% (0.036, 7.196), 4.129% (0.076, 7.963), and 4.574% (1.009, 7.762), respectively. High-level PM2.5, PM10, and O3 were not associated with stroke morbidity at low-temperature conditions. The effects of high temperature and high pollution on stroke morbidity were statistically significant among immigrants and patients with hypertension, dyslipidemia, or diabetes but insignificant among natives and patients without complications. The associations of summer temperature and air pollution with first-ever stroke morbidity may be enhanced bidirectionally. Publicity on the health risks of combined high temperature and high pollution events should be strengthened to raise protection awareness of relevant vulnerable populations.

Joint Exposure to Ambient Air Pollutants, Genetic Risk, and Ischemic Stroke: A Prospective Analysis in UK Biobank

BACKGROUND

Our primary objective was to assess the association between joint exposure to various air pollutants and the risk of ischemic stroke (IS) and the modification of the genetic susceptibility.

METHODS

This observational cohort study included 307 304 British participants from the United Kingdom Biobank, who were stroke-free and possessed comprehensive baseline data on genetics, air pollutant exposure, alcohol consumption, and dietary habits. All participants were initially enrolled between 2006 and 2010 and were followed up until 2022. An air pollution score was calculated to assess joint exposure to 5 ambient air pollutants, namely particulate matter with diameters equal to or <2.5 µm, ranging from 2.5 to 10 µm, equal to or <10 µm, as well as nitrogen oxide and nitrogen dioxide. To evaluate individual genetic risk, a polygenic risk score for IS was calculated for each participant. We adjusted for demographic, social, economic, and health covariates. Cox regression models were utilized to estimate the associations between air pollution exposure, polygenic risk score, and the incidence of IS.

RESULTS

Over a median follow-up duration of 13.67 years, a total of 2476 initial IS events were detected. The hazard ratios (95% CI) of IS for per 10 µg/m3 increase in particulate matter with diameters equal to or <2.5 µm, ranging from 2.5 to 10 µm, equal to or <10 µm, nitrogen dioxide, and nitrogen oxide were 1.73 (1.33-2.14), 1.24 (0.88-1.70), 1.13 (0.89-1.33), 1.03 (0.98-1.08), and 1.04 (1.02-1.07), respectively. Furthermore, individuals in the highest quintile of the air pollution score exhibited a 29% to 66% higher risk of IS compared with those in the lowest quintile. Notably, participants with both high polygenic risk score and air pollution score had a 131% (95% CI, 85%-189%) greater risk of IS than participants with low polygenic risk score and air pollution score.

CONCLUSIONS

Our findings suggested that prolonged joint exposure to air pollutants may contribute to an increased risk of IS, particularly among individuals with elevated genetic susceptibility to IS.

Residential Nitrogen Dioxide Exposure and Cause-Specific Cerebrovascular Mortality: An Individual-Level, Case-Crossover Study

BACKGROUND

Existing studies have already shown a connection between nitrogen dioxide (NO2) exposure and cerebrovascular mortality. However, the differential effects of NO2 on cerebrovascular disease and its subtypes remain unclear and require further exploration.

METHODS

Daily stroke mortality data between 2013 and 2021 in Shanghai, China were collected. Residential daily air pollution data for each decedent were predicted from a satellite model. An individual-level, time-stratified, case-crossover design was applied to examine the relationship between NO2 exposure and cerebrovascular mortality. A combination of conditional logistic regression and distributed lag models with a maximum lag of 7 days was used for data analysis.

RESULTS

A total of 219,147 cases of cerebrovascular mortality were recorded. Among them, the proportion of sequelae of cerebrovascular disease, hemorrhagic stroke and ischemic stroke was 50.7%, 17.1% and 27.5%, respectively. The monotonic increases in mortality risks of cerebrovascular diseases, sequelae of cerebrovascular disease and ischemic stroke were observed, without any discernible thresholds. Each 10 μg/m3 increase in NO2 concentration was associated with increments of 3.62% [95% confidence interval (CI): 2.56%, 4.69%] for total cerebrovascular mortality, 4.29% (95% CI: 2.81%, 5.80%) for sequelae of cerebrovascular disease mortality and 4.30% (95% CI: 2.30%, 6.33%) for ischemic stroke mortality. No positive associations between NO2 exposure and hemorrhagic stroke mortality were observed. A greater risk of NO2 was observed in the warm season, in patients with less than 9 years of education and in those with single marital status. The effects of NO2 were robust to mutual adjustment of co-pollutants.

CONCLUSIONS

Short-term exposures to NO2 may increase the risk of cerebrovascular mortality, specifically for ischemic stroke and sequelae of cerebrovascular disease.

Hourly Air Pollution Exposure and Emergency Hospital Admissions for Stroke: A Multicenter Case-Crossover Study

BACKGROUND

Daily exposure to ambient air pollution is associated with stroke morbidity and mortality; however, the association between hourly exposure to air pollutants and risk of emergency hospital admissions for stroke and its subtypes remains relatively unexplored.

METHODS

We obtained hourly concentrations of fine particulate matter (PM2.5), respirable particulate matter (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO) from the China National Environmental Monitoring Center. We conducted a time-stratified case-crossover study among 86 635 emergency hospital admissions for stroke across 10 hospitals in 3 cities (Jinhua, Hangzhou, and Zhoushan) in Zhejiang province, China, between January 1, 2016 and December 31, 2021. Using a conditional logistic regression combined with a distributed lag linear model, we estimated the association between hourly exposure to multiple air pollutants and risk of emergency hospital admissions for total stroke, ischemic stroke, hemorrhagic stroke, and undetermined type.

RESULTS

Hourly exposure to PM2.5, PM10, NO2, and SO2 was associated with an increased risk of hospital admissions for total stroke and ischemic stroke. The associations were most pronounced during the concurrent hour of exposure and lasted for ≈2 hours. We found that the risk was more pronounced among male patients or those aged <65 years old.

CONCLUSIONS

Our findings suggest that exposure to PM2.5, PM10, NO2, and SO2, but not CO and O3, is associated with emergency hospital admissions for total stroke or ischemic stroke shortly after exposure. Implementing targeted pollution emission reduction measures may have significant public health implications in controlling and reducing the burden of stroke.

Cleaner outdoor air diminishes the overall risk of intracerebral hemorrhage but brings differential benefits to subpopulations: a time-stratified case-crossover study

BACKGROUND

Short-term air pollution exposure and intracerebral hemorrhage (ICH) risk are related. However, the impact of the pollutant levels decline on this relationship, which attributes to clean air policy implementation and the COVID-19 pandemic lockdown, is unclear. In the present research, we explored the influence of different pollutant levels on ICH risk during eight years in a southwestern China megacity.

METHODS

Our research used a time-stratified case-crossover design. We retrospectively analyzed ICH patients in a teaching hospital from January 1, 2014, to December 31, 2021, and divided 1571 eligible cases into two groups (1st group: 2014-2017; 2nd group: 2018-2021). We observed the trend of every pollutant in the entire study period and compared the pollution levels in each group, using air pollutants data (PM2.5, PM10, SO2, NO2, CO, and O3) documented by the local government. We further established a single pollutant model via conditional logistic regression to analyze the association between short-term air pollutants exposure and ICH risk. We also discussed the association of pollution levels and ICH risk in subpopulations according to individual factors and monthly mean temperature.

RESULTS

We found that five air pollutants (PM2.5, PM10, SO2, NO2, CO) exhibited a continuous downward trend for the whole duration, and the daily concentration of all six pollutants decreased significantly in 2018-2021 compared with 2014-2017. Overall, the elevation of daily PM2.5, SO2, and CO was associated with increased ICH risk in the first group and was not positively associated with risk escalation in the second group. For patients in subgroups, the changes in the influence of lower pollutant levels on ICH risk were diverse. In the second group, for instance, PM2.5 and PM10 were associated with lower ICH risk in non-hypertension, smoking, and alcohol-drinking participants; however, SO2 had associations with increased ICH risk for smokers, and O3 had associations with raised risk in men, non-drinking, warm month population.

CONCLUSIONS

Our study suggests that decreased pollution levels diminish the adverse effects of short-term air pollutants exposure and ICH risk in general. Nevertheless, the influence of lower air pollutants on ICH risk in subgroups is heterogeneous, indicating unequal benefits among subpopulations.

Air pollution and stroke hospitalization in the Beibu Gulf Region of China: A case-crossover analysis

BACKGROUND

The relationship between air pollution and stroke has been extensively studied, however, the evidence regarding the association between air pollution and hospitalization due to stroke and its subtypes in coastal areas of China is limited.

OBJECTIVE

To estimate the associations between air pollution and hospitalizations of stroke and its subtypes in the Beibu Gulf Region of China.

METHODS

We conducted a time-stratified case-crossover study in 15 cities in Beibu Gulf Region in China from 2013 to 2016. Exposures to PM₁, PM_2.5, PM₁₀, SO₂, NO₂, O₃, and CO on the case and control days were assessed at residential addresses using bilinear interpolation. Conditional logistic regressions were constructed to estimate city-specific associations adjusting for meteorological factors and public holidays. Meta-analysis was further conducted to pool all city-level estimates.

RESULTS

There were 271,394 case days and 922,305 control days. The odds ratios (ORs) for stroke hospitalizations associated with each interquartile range (IQR) increase in 2-day averages of SO₂ (IQR: 10.8 µg/m³), NO₂ (IQR: 11.2 µg/m³), and PM₁₀ (IQR: 37 µg/m³) were 1.047 (95 % CI [confidence interval]: 1.015-1.080), 1.040 (95 % CI: 1.027-1.053), and 1.018 (95 % CI: 1.004-1.033), respectively. The associations with hospitalizations of ischemic stroke were significant for all seven pollutants, while the association with hemorrhagic stroke was significant only for CO. The associations of SO₂, NO₂, and O₃ with stroke hospitalization were significantly stronger in the cool season.

CONCLUSIONS

Short-term increase in SO₂, NO₂, and PM₁₀ might be important triggers of stroke hospitalization. All seven air pollutants were associated with ischemic stroke hospitalization, while only CO was associated with hemorrhagic stroke hospitalization. These results should be considered in public health policy.

Clustering of Environmental Parameters and the Risk of Acute Ischaemic Stroke

Acute ischaemic stroke (AIS) risk on days with similar environmental profiles remains unknown. We investigated the association between clusters of days with similar environmental parameters and AIS incidence in Singapore. We grouped calendar days from 2010 to 2015 with similar rainfall, temperature, wind speed, and Pollutant Standards Index (PSI) using k-means clustering. Three distinct clusters were formed 'Cluster 1' containing high wind speed, 'Cluster 2' having high rainfall, and 'Cluster 3' having high temperatures and PSI. We aggregated the number of AIS episodes over the same period with the clusters and analysed their association using a conditional Poisson regression in a time-stratified case-crossover design. Comparing the three clusters, Cluster 3 had the highest AIS occurrence (IRR 1.09; 95% confidence interval (CI) 1.05-1.13), with no significant difference between Clusters 1 and 2. Subgroup analyses in Cluster 3 showed that AIS risk was amplified in the elderly (≥65 years old), non-smokers, and those without a history of ischaemic heart disease/atrial fibrillation/vascular heart disease/peripheral vascular disease. In conclusion, we found that AIS incidence may be higher on days with higher temperatures and PSI. These findings have important public health implications for AIS prevention and health services delivery during at-risk days, such as during the seasonal transboundary haze.

Short-term associations of ambient air pollution with hospital admissions for ischemic stroke in 97 Japanese cities

The short-term association between ambient air pollution and hospital admissions for ischemic stroke is not fully understood. We examined the association between four regularly measured major ambient air pollutants, i.e., sulfur dioxide (SO₂), nitrogen dioxide (NO₂), photochemical oxidants (O_x), and particulate matter with aerodynamic diameters ≤ 2.5 μm (PM_2.5), and hospital admissions for ischemic stroke by analyzing 3 years of nationwide claims data from 97 cities in Japan. We first estimated city-specific results by using generalized additive models with a quasi-Poisson regression, and we obtained the national average by combining city-specific results with the use of random-effect models. We identified a total of 335,248 hospital admissions for ischemic stroke during the 3-year period. Our analysis results demonstrated that interquartile range increases in the following four ambient air pollutants were significantly associated with hospital admissions for ischemic stroke on the same day: SO₂ (1.05 ppb), 1.05% (95% CI: 0.59-1.50%); NO₂ (6.40 ppb), 1.10% (95% CI: 0.61-1.59%); O_x (18.32 ppb), 1.43% (95% CI: 0.81-2.06%); and PM_2.5 (7.86 μg/m³), 0.90% (95% CI: 0.35-1.45%). When the data were stratified by the hospital admittees' medication use, we observed stronger associations with SO₂, NO₂, and PM_2.5 among the patients who were taking antihypertensive drugs and weaker associations with SO₂, NO₂, and O_x among those taking antiplatelet drugs. Short-term exposure to ambient air pollution was associated with increased hospital admissions for ischemic stroke, and medication use and season may modify the association.

Acute Gaseous Air Pollution Exposure and Hospitalizations for Acute Ischemic Stroke: A Time-Series Analysis in Tianjin, China

BACKGROUND

Stroke has always been an important problem troubling human health. Short-term exposure to air pollutants is associated with increased hospital admissions. The rise of pollutants such as O₃ has caused a huge social and economic burden. This study aims to explore the relationship between short-term exposure to ambient gaseous pollutants and daily hospitalizations for ischemic stroke, utilizing a four-year time-series study in Tianjin.

METHODS

Collecting the data of gaseous pollutants (NO₂, SO₂, CO, O₃), meteorological data (including daily average temperature and relative humidity) and the number of hospitalizations due to ischemic stroke in Tianjin Medical University General Hospital from 2013 to 2016. Poisson regression generalized additive model with single-day and multi-day moving average lag structure was used to estimate adverse effects of gaseous pollutants on daily hospitalizations. Subgroup analysis was performed to detect modification effect by gender and age.

RESULTS

In total, there were 9081 ischemic stroke hospitalizations. After controlling for the meteorological factors in the same period, no significant findings were found with the increase of NO₂, SO₂, CO and O₃ concentrations at most of the time in the single-pollutant model. Similarly, in the stratified analysis, no associations between gaseous pollutants and ischemic stroke were observed in this study.

CONCLUSIONS

Short-term exposure to NO₂, SO₂, CO and O₃ was not distinctly associated with daily hospitalizations for ischemic stroke in Tianjin. Multicenter studies in the future are warranted to explore the associations between gaseous pollution exposure and ischemic stroke.

Short-term exposure to nitrogen dioxide and ischemic stroke incidence in Shenzhen, China: Modification effects by season and temperature

BACKGROUND AND OBJECTIVES

China has experienced a serious public health burden because of the increased incidence of ischemic stroke. Evidence describing the association between short-term exposure to nitrogen dioxide (NO₂) and ischemic stroke morbidity is limited, and few studies have focused on the effects of season and temperature. This study aimed to evaluate the acute effects of NO₂ on ischemic stroke incidence in Shenzhen, a southeastern city of China, considering the modified effects of season and temperature.

METHODS

A time-stratified case-crossover study was conducted between 2003 and 2014 among 98,482 ischemic stroke hospitalizations. Conditional quasi-Poisson regression was used to estimate the percentage changes in ischemic stroke admissions in relation to each 10 μg/m³ increment in NO₂.

RESULTS

NO₂ was positively associated with ischemic stroke onset over the full year, as well as in the cold season (November through April) and on cold days (ambient temperature≤median temperature), with significant single-day effects within 3 days after the exposure, and significant cumulative effects within the delayed five days. The maximum percentage changes were obtained at lag0-5, with 1.81% (95% confidence interval (CI) was 0.86-2.76%) over the full year, 2.75% (1.48-4.03%) in the cold season, and 3.04% (1.74-4.35%) on cold days. Additionally, the effects of exposure were found to be greater in males and people with higher education, and were lasting longer in subgroups of older individuals.

CONCLUSIONS

Our findings provide evidence that reductions in NO₂ levels might decrease ischemic stroke morbidity, and enhance the understanding of ischemic stroke occurrence associated with NO₂ modified by season and temperature.

Air Pollution and Its Devastating Effects on the Central Nervous System

Air pollution is a real public health problem, it being one of the five most common causes of mortality in developing countries. However, pollution studies have focused on the cardiovascular and pulmonary systems in recent decades. Recently, researchers have moved towards a new direction, tracing a direct link between pollution and stroke. Stroke has many known risk factors such as smoking, a sedentary lifestyle, and hypertension. Pollution is universally widespread, already a matter of public interest, so that, although intuitive, it is difficult to connect the two. The particles found in the air that we breathe, regardless of their origin, can attack the body in different ways, causing inflammation, and triggering a true cascade of phenomena that end up attacking the central nervous system and other organs. This article tries to explain the series of phenomena that determine the harmful effect of particles present in the air, with an increased focus on the central nervous system and especially on strokes. A deeper understanding of these phenomena helps in guiding future studies and finding viable solutions to protect people at risk.

Short-Term Effects of Low-Level Ambient Air NO2 on the Risk of Incident Stroke in Enshi City, China

Previous studies found that exposure to ambient nitrogen dioxide (NO₂) was associated with an increased risk of incident stroke, but few studies have been conducted for relatively low NO₂ pollution areas. In this study, the short-term effects of NO₂ on the risk of incident stroke in a relatively low-pollution area, Enshi city of Hubei Province, China, were investigated through time-series analysis. Daily air-pollution data, meteorological data, and stroke incidence data of residents in Enshi city from 1 January 2015 to 31 December 2018 were collected. A time-series analysis using a generalised additive model (GAM) based on Poisson distribution was applied to explore the short-term effects of low-level NO₂ exposure on the risk of incident stroke and stroke subtypes, as well as possible age, sex, and seasonal differences behind the effects. In the GAM model, potential confounding factors, such as public holidays, day of the week, long-term trends, and meteorological factors (temperature and relative humidity), were controlled. A total of 9122 stroke incident cases were included during the study period. We found that NO₂ had statistically significant effects on the incidence of stroke and ischemic stroke, estimated by excess risk (ER) of 0.37% (95% CI: 0.04–0.70%) and 0.58% (95% CI: 0.18–0.98%), respectively. For the cumulative lag effects, the NO₂ still had a statistically significant effect on incident ischemic stroke, estimated by ER of 0.61% (95% CI: 0.01–1.21%). The two-pollutant model showed that the effects of NO₂ on incident total stroke were still statistically significant after adjusting for other air pollutants (PM_2.5, PM₁₀, SO₂, CO, and O₃). In addition, the effects of NO₂ exposure on incident stroke were statistically significant in elderly (ER = 0.75%; 95% CI: 0.11–1.40%), males (ER = 0.47%; 95% CI: 0.05–0.89%) and cold season (ER = 0.83%; 95% CI: 0.15–1.51%) subgroups. Our study showed that, as commonly observed in high-pollution areas, short-term exposure to low-level NO₂ was associated with an increased risk of incident stroke, including ischemic stroke. Males and elderly people were more vulnerable to the effects of NO₂, and the adverse effects might be promoted in the cold season.

Short-Term Association of Air Pollutant Levels and Hospital Admissions for Stroke and Effect Modification by Apparent Temperature: Evidence From Shanghai, China

The epidemiological evidence on relationships between air pollution, temperature, and stroke remains inconclusive. Limited evidence is available for the effect modification by apparent temperature, an indicator reflecting reactions to the thermal environment, on short-term associations between air pollution and hospital admissions for stroke. We used a generalized additive model with Poisson regression to estimate the relative risk (RR) of stroke admissions in Shanghai, China, between 2014 and 2016 associated with air pollutants, with subgroup analyses by age, sex, apparent temperature, and season. During the study period, changes in the daily number of stroke admissions per 10 μg/m³ increase in nitrogen dioxide (at lags 0, 1, 0–1, and 0–2) ranged from 1.05 (95% CI: 0.82%, 2.88%) to 2.24% (95% CI: 0.84%, 3.65%). For each 10 μg/m³ increase in sulfur dioxide concentrations at lags 1, 2, 0–1, and 0–2, the RR of daily stroke admissions increased by 3.34 (95% CI: 0.955%, 5.79%), 0.32 (95% CI: −1.97%, 2.67%), 3.33 (95% CI: 0.38%, 6.37%), and 2.86% (95% CI: −0.45%, 6.28%), respectively. The associations of same-day exposure to nitrogen dioxide with stroke admissions remained significant after adjustment for ozone levels. These associations were not modified by sex, age, apparent temperature, or season. More research is warranted to determine whether apparent temperature modifies the associations between air pollution and stroke admissions.

Ambient air pollution and the risk of ischaemic and haemorrhagic stroke

Stroke is a leading cause of disability and the second most common cause of death worldwide. Increasing evidence suggests that air pollution is an emerging risk factor for stroke. Over the past decades, air pollution levels have continuously increased and are now estimated to be responsible for 14% of all stroke-associated deaths. Interpretation of previous literature is difficult because stroke was usually not distinguished as ischaemic or haemorrhagic, nor by cause. This Review summarises the evidence on the association between air pollution and the different causes of ischaemic stroke and haemorrhagic stroke, to clarify which people are most at risk. The risk for ischaemic stroke is increased after short-term or long-term exposure to air pollution. This effect is most pronounced in people with cardiovascular burden and stroke due to large artery disease or small vessel disease. Short-term exposure to air pollution increases the risk of intracerebral haemorrhage, a subtype of haemorrhagic stroke, whereas the effects of long-term exposure are less clear. Limitations of the current evidence are that studies are prone to misclassification of exposure, often rely on administrative data, and have insufficient clinical detail. In this Review, we provide an outlook on new research opportunities, such as those provided by the decreased levels of air pollution due to the current COVID-19 pandemic.

Ambient air pollution and cerebrovascular disease mortality: an ecological time-series study based on 7-year death records in central China

Most studies of short-term exposure to ambient air pollution and cerebrovascular diseases focused on specific stroke-related outcomes, and results were inconsistent due to data unavailability and limited sample size. It is unclear yet how ambient air pollution contributes to the total cardiovascular mortality in central China. Daily deaths from cerebrovascular diseases were obtained from the Disease Surveillance Point System (DSPs) of Wuhan Center for Disease Control and Prevention during the period from 2013 to 2019. Air pollution data were obtained from Wuhan Ecology and Environment Institute from 10 national air quality monitoring stations, including average daily PM_2.5, PM₁₀, SO₂, NO₂, and O₃. Average daily temperature and relative humidity were obtained from Wuhan Meteorological Bureau. We performed a Poisson regression in generalized additive models (GAM) to examine the association between ambient air pollution and cerebrovascular disease mortality. We observed a total of 84,811 deaths from cerebrovascular diseases from 1 January 2013 to 31 December 2019 in Wuhan. Short-term exposure to PM_2.5, PM₁₀, SO₂, and NO₂ was positively associated with daily deaths from cerebrovascular diseases, and no significant association was found for O₃. The largest effect on cerebrovascular disease mortality was found at lag0 for PM_2.5 (ERR: 0.927, 95% CI: 0.749-1.105 per 10 μg/m3) and lag1 for PM₁₀ (ERR: 0.627, 95% CI: 0.493-0.761 per 10 μg/m³), SO₂ (ERR: 2.518, 95% CI: 1.914, 3.122 per 10 μg/m³), and NO₂ (ERR: 1.090, 95% CI: 0.822-1.358 per 10 μg/m³). The trends across lags were statistically significant. The stratified analysis demonstrated that females were more susceptible to SO₂ and NO₂, while elder individuals aged above 65 years old, compared with younger people, suffered more from air pollution, especially from SO₂. Short-term exposure to PM_2.5, PM₁₀, SO₂, and NO₂ were significantly associated with a higher risk of cerebrovascular disease mortality, and elder females seemed to suffer more from air pollution. Further research is required to reveal the underlying mechanisms.