Kim Ayoung, Park Jinah, Kang Cinoo, Kim Ho, Lee Whanhee
Department of Public Health Sciences, Graduate School of Public health, Seoul National University, Seoul, South Korea.
School of Biomedical Convergence Engineering, Pusan National University, Yangsan, South Korea.
Int J Epidemiol. 2025 Feb 16;54(2). doi: 10.1093/ije/dyaf027.
Previous studies have reported simple differences in extreme temperature-related health risks by low socioeconomic status; however, few have examined in depth the double disparities in the socially marginalized people by age groups, sexes, disabilities, and causes of hospitalization. This study examined (i) the differences between heat- and cold-related risks on hospitalization between people who are eligible and non-eligible for the medical aid system in the national health insurance service system and (ii) differences between the heat- and cold-related risk and cost differences by specific subgroups in South Korea.
We collected population-based longitudinal cohort data from the National Health Insurance Service-National Health Insurance Database from 2010 to 2019. The data included all individuals who were eligible for the Korean Medical Aid (MA) system during the study period and we used their data on hospitalization through the emergency department (ED). As a control group, we collected age-sex-residential address-matched individuals who were not eligible for the MA system. We adopted a case-crossover design with a distributed lag nonlinear model to evaluate the excess risks and costs associated with cold and heat temperatures on hospital admissions via the emergency room department.
During the study period, 509 480 hospital admissions via the ED were recorded among 1 466 176 beneficiaries who were eligible for MA. Among the MA beneficiaries, the estimated risk for ED admission that was attributable to heat was 1.19 [95% confidence interval (CI): 1.14-1.24] and the risk that was attributable to cold temperature was 1.52 (95% CI: 1.43-1.61), which were both higher than those of the control groups that incorporated matched beneficiaries who were not eligible for MA. For both heat and cold, the difference between MA and non-MA was prominent in non-elderly populations, males, people with disabilities, and admissions with mental and cardiovascular diseases.
This study revealed the hypothesis that the differences between heat- and cold-related risks in the socially marginalized population existed and suggested that the disparities might also be disproportionate by socioeconomic and demographic statuses.
以往研究报告了社会经济地位较低者在极端温度相关健康风险方面的简单差异；然而，很少有研究深入探讨按年龄组、性别、残疾状况和住院原因划分的社会边缘化人群中的双重差异。本研究考察了：（i）在国家健康保险服务系统中，医疗救助系统合格者与非合格者之间因高温和低温导致的住院风险差异；（ii）韩国特定亚组中高温和低温相关风险及成本差异。
我们从2010年至2019年的国家健康保险服务 - 国家健康保险数据库中收集了基于人群的纵向队列数据。数据包括研究期间所有符合韩国医疗救助（MA）系统资格的个体，我们使用了他们通过急诊科（ED）住院的数据。作为对照组，我们收集了年龄、性别、居住地址匹配但不符合MA系统资格的个体。我们采用病例交叉设计和分布滞后非线性模型来评估通过急诊室因寒冷和炎热温度导致的住院额外风险和成本。
在研究期间，1466176名符合MA资格的受益人中，通过ED记录了509480次住院。在MA受益人中，因高温导致的ED入院估计风险为1.19[95%置信区间（CI）：1.14 - 1.24]，因低温导致的风险为1.52（95%CI：1.43 - 1.61），两者均高于纳入不符合MA资格的匹配受益人的对照组。对于高温和低温，MA与非MA之间的差异在非老年人群、男性、残疾人和因精神和心血管疾病住院的患者中尤为突出。
本研究揭示了社会边缘化人群中高温和低温相关风险存在差异的假设，并表明这些差异可能因社会经济和人口统计学状况而异。
