BACKGROUND More frequent and intense exposure to extreme heat conditions poses a serious threat to public health. However, evidence on the association between heat and specific diagnoses of morbidity is still limited. We aimed to comprehensively assess the short-term association between cause-specific hospital admissions and high temperature, including the added effect of temperature variability and heat waves and the effect modification by humidity and air pollution. METHODS We used data on cause-specific hospital admissions, weather (i.e., temperature and relative humidity), and air pollution [i.e., fine particulate matter with aerodynamic diameter ≤2.5μm (PM2.5), fine particulate matter with aerodynamic diameter ≤10μm (PM10), NO2, and ozone (O3)] for 48 provinces in mainland Spain and the Balearic Islands between 1 January 2006 and 31 December 2019. The statistical analysis was performed for the summer season (June-September) and consisted of two steps. We first applied quasi-Poisson generalized linear regression models in combination with distributed lag nonlinear models (DLNM) to estimate province-specific temperature-morbidity associations, which were then pooled through multilevel univariate/multivariate random-effect meta-analysis. RESULTS High temperature had a generalized impact on cause-specific hospitalizations, while the added effect of temperature variability [i.e., diurnal temperature range (DTR)] and heat waves was limited to a reduced number of diagnoses. The strongest impact of heat was observed for metabolic disorders and obesity [relative risk (RR) = 1.978; 95% empirical confidence interval (eCI): 1.772, 2.208], followed by renal failure (1.777; 95% eCI: 1.629, 1.939), urinary tract infection (1.746; 95% eCI: 1.578, 1.933), sepsis (1.543; 95% eCI: 1.387, 1.718), urolithiasis (1.490; 95% eCI: 1.338, 1.658), and poisoning by drugs and nonmedicinal substances (1.470; 95% eCI: 1.298, 1.665). We also found differences by sex (depending on the diagnosis of hospitalization) and age (very young children and the elderly were more at risk). Humidity played a role in the association of heat with hospitalizations from acute bronchitis and bronchiolitis and diseases of the muscular system and connective tissue, which were higher in dry days. Moreover, heat-related effects were exacerbated on high pollution days for metabolic disorders and obesity (PM2.5) and diabetes (PM10, O3). DISCUSSION Short-term exposure to heat was found to be associated with new diagnoses (e.g., metabolic diseases and obesity, blood diseases, acute bronchitis and bronchiolitis, muscular and connective tissue diseases, poisoning by drugs and nonmedicinal substances, complications of surgical and medical care, and symptoms, signs, and ill-defined conditions) and previously identified diagnoses of hospital admissions. The characterization of the vulnerability to heat can help improve clinical and public health practices to reduce the health risks posed by a warming planet. https://doi.org/10.1289/EHP13254.

中文翻译：

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西班牙的热暴露和特定原因入院：一项全国范围的横断面研究。


背景技术更频繁和强烈地暴露于极端高温条件对公众健康构成严重威胁。然而，关于高温与具体发病诊断之间关联的证据仍然有限。我们的目的是全面评估特定原因入院与高温之间的短期关联，包括温度变化和热浪的附加影响以及湿度和空气污染的影响修正。方法 我们使用了特定原因入院、天气（即温度和相对湿度）和空气污染（即空气动力学直径≤2.5μm的细颗粒物（PM2.5）、空气动力学直径≤10μm的细颗粒物）的数据。 2006年1月1日至2019年12月31日期间西班牙大陆48个省份和巴利阿里群岛的PM10、NO2和臭氧（O3）。统计分析针对夏季（6月至9月）进行，包括两个步骤。我们首先应用准泊松广义线性回归模型与分布式滞后非线性模型（DLNM）相结合来估计各省特定的温度-发病率关联，然后通过多级单变量/多变量随机效应荟萃分析将其汇总。结果 高温对特定原因的住院治疗有普遍影响，而温度变化[即昼夜温度范围(DTR)]和热浪的附加影响仅限于诊断数量的减少。观察到高温对代谢紊乱和肥胖的影响最强[相对风险 (RR) = 1.978； 95% 经验置信区间 (eCI)：1.772, 2.208]，其次是肾衰竭（1.777；95% eCI：1.629，1.939）、尿路感染（1.746；95% eCI：1.578、1.933）、脓毒症（1.543；95） % eCI：1。387, 1.718)、尿石症(1.490; 95% eCI: 1.338, 1.658)以及药物和非药物中毒(1.470; 95% eCI: 1.298, 1.665)。我们还发现了性别（取决于住院诊断）和年龄（幼儿和老年人的风险更大）的差异。湿度在高温与急性支气管炎、细支气管炎以及肌肉系统和结缔组织疾病住院的关联中发挥了重要作用，这些疾病在干燥的日子里更高。此外，在代谢紊乱、肥胖（PM2.5）和糖尿病（PM10、O3）的高污染天，与热相关的影响会加剧。讨论 短期暴露于高温被发现与新的诊断有关（例如代谢性疾病和肥胖、血液疾病、急性支气管炎和细支气管炎、肌肉和结缔组织疾病、药物和非药物中毒、手术和医疗护理并发症）以及症状、体征和不明确的情况）以及之前确定的入院诊断。热脆弱性的表征有助于改善临床和公共卫生实践，以减少地球变暖带来的健康风险。 https://doi.org/10.1289/EHP13254。