Districts In South Korea Research Articles

Urban Livability Assessment in South Korea: Incorporating Climate Change Vulnerability

This study aims to develop an urban livability assessment index that incorporates climate change vulnerability and to apply this index to urban areas in South Korea, thereby analyzing the impact of climate change on living environments and quality of life. Existing frameworks for livability indices often fail to adequately reflect the long-term risks associated with climate change. Consequently, this research proposes a new livability index that includes climate change vulnerability, establishing a policy foundation aimed at protecting and enhancing the quality of life for urban residents. The methodology integrates existing livability indicators with climate change vulnerability indicators across 219 cities and districts in South Korea. Utilizing panel regression analysis and Local Indicators of Spatial Association (LISA) analysis, the study evaluates the spatial clustering characteristics and potential risks in each area. The results indicate that urban infrastructure significantly influences livability, with climate change vulnerability indicators forming high clusters primarily in southern regions. Furthermore, the study confirms economic disparities within the metropolitan area, as well as the exacerbation of social inequalities in regions vulnerable to disaster safety and social services. This research underscores the necessity of integrating climate change vulnerability into livability indices, suggesting that such indices can serve as critical criteria for urban policy formulation and the evaluation of regeneration projects.

Regional inequalities in excess mortality and its community determinants during the early COVID-19 pandemic in South Korea

BackgroundExcess mortality during the COVID-19 pandemic provides a comprehensive measure of disease burden, and its local variation highlights regional health inequalities. We investigated local excess mortality in 2020 and its...

Summer temperature and emergency room visits due to urinary tract infection in South Korea: a national time-stratified case-crossover study

BackgroundAlthough urinary tract infection (UTI) is a common and severe public health concern, and there are clear biological mechanisms between UTI and hot temperatures, few studies have addressed the association between hot temperatures and UTI.MethodsWe designed a time-stratified case-crossover study using a population-representative sample cohort based on the National Health Insurance System (NHIS) in South Korea. We obtained all NHIS-based hospital admissions through the emergency room (ER) due to UTI (using a primary diagnostic code) from 2006 to 2019. We assigned satellite-based reanalyzed daily summer (June to September) average temperatures as exposures, based on residential districts of beneficiaries (248 districts in South Korea). The conditional logistic regression was performed to evaluate the association between summer temperature and UTI outcome.ResultsA total of 4,436 ER visits due to UTI were observed during the summer between 2006 and 2019 among 1,131,714 NHIS beneficiaries. For 20% increase in summer temperatures (0–2 lag days), the odd ratio (OR) was 1.06 (95% CI: 1.02–1.10) in the total population, and the association was more prominent in the elderly (people aged 65 y or older; OR:1.11, 95% CI: 1.05–1.17), females (OR: 1.12, 95% CI: 1.05–1.19), and people with diabetes history (OR: 1.14, 95% CI: 1.07–1.23). The effect modification by household income was different in the total and elderly populations. Furthermore, the association between summer temperature and UTI increased during the study period in the total population.ConclusionsOur results are consistent with the hypothesis that higher summer temperatures increase the risk of severe UTIs, and the risk might be different by sub-populations.

Geographic disparities in brachytherapy accessibility for cervical cancer.

1577 Background: While brachytherapy stands as a crucial component of the treatment for locally advanced cervical cancer, the issue of geographic disparities in brachytherapy accessibility has become a noteworthy public health concern in South Korea. Moreover, the specific factors contributing to these disparities have not been clearly elucidated. In light of this, we conducted a nationwide ecologic study to comprehensively investigate the socioeconomic factors associated with brachytherapy accessibility. Methods: A total of 2,998 patients newly diagnosed with cervical cancer in 2020 were identified through the Korea Central Cancer Registry (KCCR). Across 17 administrative districts in South Korea, 32 brachytherapy facilities were available. To capture unique socioeconomic factors for each region, including the number of Korean Medicaid (K-Medicaid), Medicare (K-Medicare) beneficiaries, marriage immigrants, registered foreigners, and total residents, data were obtained from the Korean Statistical Information Service (KOSIS). Notably, K-Medicaid and K-Medicare represent governmental medical insurance assistance for patients in poverty and those aged over 65, respectively. The brachytherapy accessibility rate (BAR) was defined as the number of brachytherapy procedures divided by new cervical cancer cases. Additionally, each district's socioeconomic factor was normalized by the number of residents. Univariate and multivariate logistic regression analyses were conducted to explore the relationships between BAR and socioeconomic factors. Results: The capital city and its adjoining metropolitan area accounted for 46.9% of the total brachytherapy facilities, with Seoul having 25% (8 out of 32) and Gyeonggi having 21.9% (7 out of 32). Conversely, three non-metropolitan regions had no brachytherapy facilities. In the multivariate logistic regression analysis, the brachytherapy accessibility rate (BAR) demonstrated an inverse association with both the number of K-Medicare beneficiaries and the total immigrant population (Odds ratios of 0.66 and -2.85, respectively). Conclusions: To the best of our knowledge, this is the inaugural study highlighting the robust associations between older age and foreign residency status with reduced accessibility to brachytherapy. The observed inaccessibility to brachytherapy has the potential to impede the delivery of standard care, consequently leading to a poorer prognosis for vulnerable populations. Future research endeavors and targeted social interventions will be imperative to rectify geographic disparities in brachytherapy accessibility and ensure equitable healthcare outcomes.

Comparison of Different Green Space Measures and Their Impact on Dementia Cases in South Korea: A Spatial Panel Analysis

Dementia has become a profound public health problem due to the number of patients increasing every year. Previous studies have reported that environmental factors, including greenness, may influence the development and progression of dementia. Studies have found that exposure to green space is associated with a lower incidence of dementia. However, many definitions of green space exist, and the effects of its use may differ with the type of green space. Therefore, two types of green space measures were considered in this study to assess the differences in their impact on the prevalence of dementia among females and males. This study used five years of data (2017–2021) from 235 districts in South Korea. The two green space measures used were open space density and normalized difference vegetation index (NDVI), which were derived from satellite images. The analysis utilized a combination of traditional and spatial panel analyses to account for the spatial and temporal effects of independent variables on dementia prevalence. The spatial autocorrelation results revealed that both measures of greenness were spatially correlated with dementia prevalence. The spatial panel regression results revealed a significant positive association between NDVI and dementia prevalence, and open space had a negative association with dementia prevalence in both genders. The difference in the findings can serve as the basis for further research when choosing a greenspace measure, as it affects the analysis results, depending on the objective of the study. This study adds to the knowledge regarding improving dementia studies and the application of spatial panel analysis in epidemiological studies.

Macroscale impact assessment of flood damage reduction from climate change adaptation policies

AbstractAdaptation policies are being increasingly implemented to cope with the increased frequency of natural disasters due to climate change. However, it is crucial to quantitatively evaluate the mitigating effects of these policies, as this allows for their assessment and prioritization. Therefore, this study sought to develop a nonlinear flood damage function for each administrative region of South Korea to quantify the potential damage caused by extreme rainfall events. Afterward, a power function was nested to model the coefficient of the flood damage function with regional factors characterizing each region's flood mitigation capacity. Here, regional factors were selected based on their linkage to two potential adaptation policies: enhancing retention reservoir and pumping capacity and enhancing river dike construction. The proposed evaluation framework was tested in 15 administrative districts in South Korea and the flood damage reduction effects of the two policy scenarios were estimated. The enhancement of retention reservoir and pumping capacity showed a 6.7% reduction effect, whereas enhancing river dike construction showed a 29.2% reduction effect. The implementation of both policies yielded a 34.3% reduction effect. Despite the limitations of this study, our findings still provide a quantitative comparison of the long‐term effects of national climate change adaptation measures. Additionally, accumulating more damage records would allow for the development of damage functions at a finer scale.

Particulate matters (PM2.5, PM10) and the risk of depression among middle-aged and older population: analysis of the Korean Longitudinal Study of Aging (KLoSA), 2016–2020 in South Korea

BackgroundThere is a growing concern that particulate matter (PM) such as PM2.5 and PM10 has contributed to exacerbating psychological disorders, particularly depression. However, little is known about the roles of these air pollutants on depression in elderly. Therefore, this study aimed to examine the association between PM2.5 and PM10, and depression in the elderly population in South Korea.MethodsWe used panel survey data, the Korean Longitudinal Study of Aging (KLoSA), administered by the Labor Institute during the study period of 2016, 2018, and 2020 covering 217 districts in South Korea (n = 7674). Annual district-specific PM2.5 and PM10 concentrations were calculated for the study period from the monthly prediction concentrations produced by a machine-learning-based ensemble model (cross-validated R2: 0.87), then linked to the people matching with year and their residential district. We constructed a generalized estimating equation (GEE) model with a logit link to identify the associations between each of the long-term PM2.5 and PM10 exposures and depression (CES-D 10) after adjusting for individual and regional factors as confounders.ResultsIn single-pollutant models, we found that long-term 10 mathrm{mu g}/{m}^{3} increments in PM2.5 (OR 1.36, 95% CI 1.20–1.56) and PM10 (OR 1.19, 95% CI 1.10–1.29) were associated with an increased risk of depression in the elderly. Associations were consistent after adjusting for other air pollutants (NO2 and O3) in two-pollutant models. In addition, the impacts substantially differed by regions grouped by the tertile of the population density, for which the risks of particulate matters on depression were substantial in the middle- or high-population-density areas in contrast to the low-population-density areas.ConclusionsLong-term exposure to PM2.5 and PM10 was associated with a higher risk of developing depression in elderly people. The impact was modified by the population density level of the region where they reside.

The association between demographic, economic, and medical resource factors and the inflow and outflow of critically ill emergency patients by medical service districts in South Korea

The association between demographic, economic, and medical resource factors and the inflow and outflow of critically ill emergency patients by medical service districts in South Korea

Decomposition of travel time expenditure through individual mobility trajectories based on mobile phone signaling data

The concept of travel time expenditure (TTE) or travel time budget (TTB) was developed approximately 60 years ago, and its stability issues have long been debated based on traditional household travel survey (HHTS) methods or less developed information and communication technologies (ICTs). Recent advances in mobile phone technologies have enabled the use of individuals’ mobility information at the disaggregation level. The objective of this study is to explore the TTE based on mobile phone signaling data (MPSD) collected from the residents in two different types of districts in South Korea. The results may produce better spatiotemporal precision than traditional household survey data because MPSD is generated when a mobile phone changes the cell coverage area and base transceiver stations (BTSs) or whenever the recording time interval set by the cellular service provider arrives. On the other hand, tremendous effort is needed to collect and clean up the raw data compared to data obtained using the conventional HHTS method. This paper presents data-cleaning processes and the results of a TTE calculation as a function of the day of weekday, age group, and region type. The processes and results of this study could be useful for modeling human mobility behavior using MPSD.

Role of geographic characteristics in the spatial cluster detection of cancer: Evidence in South Korea, 1999–2013

BackgroundIdentification of high-risk areas of cancer, referred to as spatial clusters, can inform targeted policies for cancer control. Although cancer cluster detection could be affected by various geographic characteristics including sociodemographic and environmental factors which impacts could also vary over time, studies accounting for such influence remain limited. This study aims to assess the role of geographic characteristics in the spatial cluster detection for lung and stomach cancer over an extended period. MethodsWe obtained sex-specific age-standardized incidence and mortality rates of lung and stomach cancer as well as geographic characteristics across 233 districts in South Korea for three five-year periods between 1999 and 2013. We classified geographic characteristics of each district into four categories: demography, socioeconomic status, behaviors, and physical environments. Specifically, we quantified physical environments using measures of greenness, concentrations of particulate matter and nitrogen dioxide, and air pollution emissions. Finally, we conducted cluster detection analyses using weighted normal spatial scan statistics with the residuals from multiple regression analyses performed with the four progressive sets of geographic attributes. ResultsWe found that the size of clusters reduced as we progressively adjusted for geographic covariates. Among the four categories, physical environments had the greatest impact on the reduction or disappearance of clusters particularly for lung cancer consistently over time. Whereas older population affected a decrease of lung cancer clusters in the early period, the contribution of education was large in the recent period. The impact was less clear in stomach cancer than lung cancer. ConclusionOur findings highlight the importance of geographic characteristics in explaining the existing cancer clusters and identifying new clusters, which jointly provides practical guidance to cancer control.

Development of a fire prediction model at the urban planning stage: Ordinary least squares regression analysis of the area of urban land use and fire damage data in South Korea

Fire risk assessment at the urban planning stage is crucial for developing fire prevention strategies and designing mitigation measures. Many studies have been conducted to support fire risk assessments in cities. However, the fire prediction models developed in those studies have been based on factors that continuously change in the urban development process. Thus, their models cannot be used in fire risk assessments or fire prevention planning at the urban planning stage. To overcome this limitation, the correlations between fire damage and land use area, as determined at the urban planning stage, were identified in this study and two fire prediction models were proposed based on the results of the analyses. To develop these models, the land use area and fire damage data for 230 districts in South Korea were collected from 2010 to 2019. The fire prediction models were proposed based on correlation analysis and ordinary least squares regression analysis. The two fire prediction models that were finally derived showed accuracies of 69% and 71%, respectively. The findings of this study can be used as basic data to support fire service planning when city plans and urban development plans are established.

Long-term Exposure to Particulate matter and cardiovascular disease in South Korea: investigating multi-level interaction with individual- and area-level factors

Background and aim: It has been well known that individuals or groups are not equally vulnerable to air pollution. However, few studies have investigated whether individual susceptibility to air pollution varies across different community environments. This study aimed to estimate the effects of long-term PM₁₀ exposure on cardiovascular disease (CVD) in South Korea and to examine whether individual status of underlying disease and area-level medical infrastructure modify the effect. Methods: The study population comprised 392,104 subjects from the National Health Insurance Service-National Sample Cohort (2006-2015) residing in 120 districts in South Korea. The CVD event was defined as the first occurrence of a hospital visit or admission from 2006 to 2015. Time‐varying Cox proportional-hazards models were used to estimate the association between five-year moving averages of PM₁₀ and CVD events. Effect modifications by the individual status of underlying disease (cancer, diabetes, and hypertension) were determined by two-way interaction, stratifying by area-level medical index (calculated with the number of hospitals, hospital beds, and medical personnel). Results: Long-term exposure to PM₁₀ was positively associated with the risk of CVD events (HR per 10 μg/m³, 1.04; 95% CI, 1.02-1.06). In areas with a low medical index, PM₁₀‐associated CVD risks were higher among those with cancer (HR 1.19; 95% CI, 1.00-1.42) as compared to those without (HR, 1.07; 95% CI, 1.02-1.12). In areas with a low medical index, subjects with cancer showed a lower risk of CVD associated with PM₁₀ than those without. Conclusions: This study suggests that the individual-level status of an underlying disease and area-level medical infrastructure could be interrelated in determining the health effect of PM₁₀. Consideration of this multi-level interaction in population vulnerability to air pollution can help understand the complex mechanisms by which air pollution creates health disparities. Keywords: Particulate matter, cardiovascular disease, effect modification, underlying disease, medical infrastructure

Proposing the classification matrix for growing and shrinking cities: A case study of 228 districts in South Korea

Many studies have attempted to categorize growing and shrinking cities primarily through population and economic indicators. However, previous approaches may have oversimplified the characteristics of city categories, such as growing or shrinking cities. Therefore, this study proposes a classification matrix based on the interaction between population and economic activity indicators to describe the characteristics of growing or shrinking cities adequately. The authors applied the matrix to categorize 228 administrative districts in South Korea, taking into account the distinct characteristics of the categorized growth and shrinkage patterns. The results show that these patterns can be subdivided into eight types of growing or shrinking cities, depending on which indicator between population or economic activity change is more predominant. The authors found that cities with declined population and increased economic activity could give rise to growth patterns. These findings suggest that the classification matrix can provide researchers and policymakers with a sophisticated analytical frame for diagnosing and classifying urban change, which can contribute to the enactment of appropriate urban and regional policies.

Suicide rate and social environment characteristics in South Korea: the roles of socioeconomic, demographic, urbanicity, general health behaviors, and other environmental factors on suicide rate

BackgroundSuicide is a serious worldwide public health concern, and South Korea has shown the highest suicide rate among Organisation for Economic Co-operation and Development (OECD) countries since 2003. Nevertheless, most previous Korean studies on suicide had limitations in investigating various social environment factors using long-term nationwide data. Thus, this study examined how various social environment characteristics are related to the suicide rate at the district-level, using nationwide longitudinal data over 11 years.MethodsWe used the district-level age-standardized suicide rate and a total of 12 annual social environment characteristics that represented socioeconomic, demographic, urbanicity, general health behaviors, and other environmental characteristics from 229 administrative districts in South Korea. A Bayesian hierarchical model with integrated Laplace approximations (INLA) was used to examine the spatiotemporal association between the rate of suicide and the social environment indicators selected for the study.ResultsIn the total population, the indicators “% of population aged 65 and older eligible for the basic pension”, “% vacant houses in the area”, “% divorce”, “% single elderly households”, “% detached houses”, “% current smokers”, and “% of population with obesity” showed positive associations with the suicide rate. In contrast, “% of people who regularly participated in religious activities” showed negative associations with suicide rate. The associations between these social environment characteristics and suicide rate were generally more statistically significant in males and more urbanized areas, than in females and less urbanized areas; however, associations differed amongst age groups, depending on the social environment characteristic variable under study.ConclusionsThis study investigated the complex role of social environments on suicide rate in South Korea and revealed that higher suicide rates were associated with lower values of socioeconomic status, physical exercise, and religious activities, and with higher social isolation and smoking practice. Our results can be used in the development of targeted suicide prevention policies.

Effects of urbanization on vulnerability to heat-related mortality in urban and rural areas in South Korea: a nationwide district-level time-series study.

Although urbanization is often an important topic in climate change studies, the complex effect of urbanization on heat vulnerability in urban and rural areas has rarely been studied. We investigated the disparate effects of urbanization on heat vulnerability in urban and rural areas, using nationwide data. We collected daily weather data for all 229 administrative districts in South Korea (2011-17). Population density was applied as an urbanization indicator. We calculated the heat-mortality risk using a distributed lag nonlinear model and analysed the relationship with population density. We also examined district characteristics that can be related to the spatial heterogeneity in heat-mortality risk. We found a U-shaped association between population density and heat-mortality risk, with the highest risk for rural populations; in urban areas, risk increases with increasing population density. Higher heat-mortality risk was associated with a lower number of hospital beds per person and higher percentage of people requiring recuperation. The association between hospital beds and heat-mortality risk was prominent in high-density urban areas, whereas the association between the percentage of people requiring recuperation and heat-mortality risk was pronounced in rural areas. Our findings indicate that the association between population density and heat-mortality risk is different in urban and rural areas, and that district characteristics related to heat-mortality risk also differ by urbanicity. These results can contribute to understanding the complex role of urbanization on heat vulnerability and can provide evidence to policy makers for prioritizing resources.

Urbanization and Vulnerability to Heat-Mortality: Different Roles of Urbanization between Urban and Rural Districts in South Korea; A Nationwide Time-series Study.

Background/Aim: Although urbanization has been an important topic in heat vulnerability studies, the complex role of urbanization, which can be different in urban and rural regions, has rarely been studied. We investigated the disparate roles of urbanization between urban and rural areas. Methods: We collected nationwide daily data for all 229 local authority districts in South Korea during 2011-2017. The districts were classified into urban (147 districts) and rural (82 districts) areas, based on the administrative districts. We applied three demographic variables (percentage of the urban population, population number, and population density) as urbanization indicators and also used medical-social environment indices to explain the role of urbanization. Results: There was no evident difference in the heat-mortality risk between urban and rural areas, and the role of urbanization was different in urban and rural areas; the higher urbanization level was associated with lower heat-mortality risk in rural areas, however, with lower heat-mortality risk in urban areas (i.e. the U-shaped relationship). The number of beds in hospital per person was associated with this U-shaped relationship, and the linkage was more evident in urban areas than in rural areas, and in the highest urbanized areas within urban areas. Meanwhile, the lower quality of health-related life and lower social gatherings were related to higher heat-mortality risk in rural areas. Conclusions: We found the urbanization level was linked in the opposite direction to the heat vulnerability in urban and rural areas, and the lower accessibility to hospital beds observed in rural and the highest urbanized areas was associated with higher heat vulnerability. Furthermore, regional indicators related to heat vulnerability were also heterogeneous between urban and rural areas. These results can contribute to understanding the complex role of urbanization in heat vulnerability and to establish evidence-based region-specific policies.

Association between long-term exposure to air pollutants and cardiopulmonary mortality rates in South Korea

BackgroundThe association between long-term exposure to air pollutants, including nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), ozone (O3), and particulate matter 10 μm or less in diameter (PM10), and mortality by ischemic heart disease (IHD), cerebrovascular disease (CVD), pneumonia (PN), and chronic lower respiratory disease (CLRD) is unclear. We investigated whether living in an administrative district with heavy air pollution is associated with an increased risk of mortality by the diseases through an ecological study using South Korean administrative data over 19 years.MethodsA total of 249 Si-Gun-Gus, unit of administrative districts in South Korea were studied. In each district, the daily concentrations of CO, SO2, NO2, O3, and PM10 were averaged over 19 years (2001–2018). Age-adjusted mortality rates by IHD, CVD, PN and CLRD for each district were averaged for the same study period. Multivariate beta-regression analysis was performed to estimate the associations between air pollutant concentrations and mortality rates, after adjusting for confounding factors including altitude, population density, higher education rate, smoking rate, obesity rate, and gross regional domestic product per capita. Associations were also estimated for two subgrouping schema: Capital and non-Capital areas (77:172 districts) and urban and rural areas (168:81 districts).ResultsFor IHD, higher SO2 concentrations were significantly associated with a higher mortality rate, whereas other air pollutants had null associations. For CVD, SO2 and PM10 concentrations were significantly associated with a higher mortality rate. For PN, O3 concentrations had significant positive associations with a higher mortality rate, while SO2, NO2, and PM10 concentrations had significant negative associations. For CLRD, O3 concentrations were associated with an increased mortality rate, while CO, NO2, and PM10 concentrations had negative associations. In the subgroup analysis, positive associations between SO2 concentrations and IHD mortality were consistently observed in all subgroups, while other pollutant-disease pairs showed null, or mixed associations.ConclusionLong-term exposure to high SO2 concentration was significantly and consistently associated with a high mortality rate nationwide and in Capital and non-Capital areas, and in urban and rural areas. Associations between other air pollutants and disease-related mortalities need to be investigated in further studies.

Land Use Change, Extreme Precipitation Events, and Flood Damage in South Korea: A Spatial Approach

Floods are major social and environmental concerns in many urban areas. We investigated how changes in land cover, sociodemographic conditions, and meteorological factors affect flood damage in districts of South Korea. Using historical maps and spatial analysis, we showed that flood damages increased in the areas where rapid urbanization happened without coordinated urban planning. High flood damage areas are not spatially randomly distributed, and the hotspots of high damage areas are concentrated in population centers that underwent rapid development after 1975. Additionally, human modifications of natural channels further exacerbated flood risks during the development stage and subsequent periods. Total annual precipitation is positively related to the flood damage at a higher spatial unit. This study underscores the importance of understanding the historical–geographical conditions, and how humans either increased or reduced the flood damage through social and infrastructure interventions. Findings of this study have implications for resilient flood management for regions that are currently facing the dual challenges of land densification and climate change-induced heavy precipitation.

Spatial heterogeneity in the association between particulate matter air pollution and low birth weight in South Korea

As many studies showed the spatial heterogeneity in the association between particulate matter (PM) air pollution and low birth weight (LBW), few studies focused on the variation of local associations at the national scale and related areal characteristics. This study aimed to explore different approaches to estimating local effects of PM with an aerodynamic diameter ≤10 μm (PM10) on LBW across 235 districts in South Korea, to investigate the spatial pattern of local associations, and to examine the relationship with local socio-demographic and environmental characteristics. LBW was identified in 5,692,650 mothers from birth certificate data for 2001–2013. We estimated individual annual-average concentrations of PM10 at centroids of mothers’ residential districts by using a previously-validated prediction model. Then, we estimated district-specific odds ratios of LBW for PM10 using modified geographically weighted logistic regression. Here, we applied four approaches with different neighborhood definitions: the distance-based approach within 20- and 40-km bandwidth and the hybrid approach replacing with adjacent districts for urban districts <100 km2. In addition, we compared district-specific socioeconomic indicators and emission estimates across three groups of districts that showed significantly positive, no, and significantly negative associations. Medians of district-specific estimates of four approaches were similar to the global estimate and between each other. However, their variability differed with some unreasonably high estimates when a small distance was applied as the neighborhood definition, although spatial pattern was generally similar among the four. The hybrid approach based on the different neighborhood definition by urban and rural areas provided stable risk estimates. Higher risk districts in rural areas were found in more socioeconomically-deprived areas, whereas urban areas showed higher risk districts when their air pollution emissions were higher. Our approach and findings will help identify high risk areas and enhance understanding of geographic determinants.

Heatwave-Related Mortality Risk and the Risk-Based Definition of Heat Wave in South Korea: A Nationwide Time-Series Study for 2011–2017

Studies on the pattern of heatwave mortality using nationwide data that include rural areas are limited. This study aimed to assess the risk of heatwave-related mortality and evaluate the health risk-based definition of heatwave. We collected data on daily temperature and mortality from 229 districts in South Korea in 2011–2017. District-specific heatwave-related mortality risks were calculated using a distributed lag model. The estimates were pooled in the total areas and for each urban and rural area using meta-regression. In the total areas, the threshold point of heatwave mortality risk was estimated at the 93rd percentile of temperature, and it was lower in urban areas than in rural areas (92nd percentile vs. 95th percentile). The maximum risk of heatwave-related mortality in the total area was 1.11 (95% CI: 1.01–1.22), and it was slightly greater in rural areas than in the urban areas (RR: 1.23, 95% CI: 0.99–1.53 vs. RR: 1.10, 95% CI: 1.01–1.20). The results differ by age- and cause-specific deaths. In conclusion, the patterns of heatwave-related mortality risk vary by area and sub-population in Korea. Thus, more target-specific heatwave definitions and action plans should be established according to different areas and populations.