High temperature and hospitalizations for cardiovascular and respiratory causes in 12 European cities.

RATIONALE: Episode analyses of heat waves have documented a comparatively higher impact on mortality than on morbidity (hospital admissions) in European cities. The evidence from daily time series studies is scarce and inconsistent. OBJECTIVES: To evaluate the impact of high environmental temperatures on hospital admissions during April to September in 12 European cities participating in the Assessment and Prevention of Acute Health Effects of Weather Conditions in Europe (PHEWE) project. METHODS: For each city, time series analysis was used to model the relationship between maximum apparent temperature (lag 0-3 days) and daily hospital admissions for cardiovascular, cerebrovascular, and respiratory causes by age (all ages, 65-74 age group, and 75+ age group), and the city-specific estimates were pooled for two geographical groupings of cities. MEASUREMENTS AND MAIN RESULTS: For respiratory admissions, there was a positive association that was heterogeneous between cities. For a 1 degrees C increase in maximum apparent temperature above a threshold, respiratory admissions increased by +4.5% (95% confidence interval, 1.9-7.3) and +3.1% (95% confidence interval, 0.8-5.5) in the 75+ age group in Mediterranean and North-Continental cities, respectively. In contrast, the association between temperature and cardiovascular and cerebrovascular admissions tended to be negative and did not reach statistical significance. CONCLUSIONS: High temperatures have a specific impact on respiratory admissions, particularly in the elderly population, but the underlying mechanisms are poorly understood. Why high temperature increases cardiovascular mortality but not cardiovascular admissions is also unclear. The impact of extreme heat events on respiratory admissions is expected to increase in European cities as a result of global warming and progressive population aging.

Number of Heat Wave Deaths by Diagnosis, Sex, Age Groups, and Area, in Slovenia, 2015 vs. 2003.

Background: Number of deaths increases during periods of elevated heat. Objectives: To examine whether differences in heat-related deaths between 2003 and 2015 occurred in Slovenia. Materials and Methods: We estimated relative risks for deaths for the observed diagnoses, sex, age, and area, as well as 95% confidence intervals and excess deaths associated with heat waves occurring in 2015 and 2003. For comparison between 2015 and 2003, we calculated relative risks ratio and 95% confidence intervals. Results: Statistically significant in 2015 were the following: age group 75+, all causes of deaths (RR = 1.10, 95% CI 1.00-1.22); all population, circulatory system diseases (RR = 1.14, 95% CI 1.01-1.30) and age group 75+, diseases of circulatory system (RR = 1.17, 95% CI 1.01-1.34). Statistically significant in 2003 were the following: female, age group 5-74, circulatory system diseases (RR = 1.69, 95% CI 1.08-2.62). Discussion: Comparison between 2015 and 2003, all, circulatory system diseases (RRR = 1.25, 95% CI 1.01-1.55); male, circulatory system diseases (RRR = 1.85, 95% CI 1.41-2.43); all, age group 75+ circulatory system diseases (RRR = 1.34, 95% CI 1.07-1.69); male, age group 75+, circulatory system diseases (RRR = 1.52, 95% CI 1.03-2.25) and female, age group 75+, circulatory system diseases (RRR = 1.43, 95% CI 1.08-1.89). Conclusions: Public health efforts are urgent and should address circulatory system causes and old age groups.