High summer temperatures induce more admissions due to AECOPD in urban hospitals

Abstract

Introduction: Patients with Chronic Obstructive Pulmonary Disease (COPD) have an increased mortality risk following extreme hot or cold outdoor temperatures. The purpose of our study is to evaluate whether outdoor temperatures have an influence on daily hospital admissions due to exacerbation of COPD (AECOPD). Methods: Hospital records from patients with exacerbation of COPD admitted to the Vivantes Hospital in Berlin, Germany, during the summer months (June, July, and August) of 2006, 2010, 2011, and 2012 were retrospectively analyzed. COPD was defined as ICD-10 Codes J44.00-J44.99. Meteorological data was provided by the local meteorological station and obtained from the website of the German Weather Service. Data from 563 patients AECOPD were included in this study. Patients admitted during the allocated time periods had a mean age of 70.5±10.5, a moderate Charlson-Index, and had a GOLD-Status of III or IV. They were both male (51.0%) and female (49.0%) and slightly overweight. Results: Our data shows a significant correlation between high outdoor temperature and number of daily hospital admissions ( R =0.105; P =0.013). The average maximum temperature (T max ) on days with maximum admissions (6 patients; A max ) was 29.6°C, whereas temperature decreased to 24.1°C on days with fewer admissions. Conclusion: Summer heat stress serves as a catalyst for daily hospital admissions in patients with COPD. Therefore, doctors should advise their patients about preventive measures on days with outdoor heat stress and hospitals should be prepared for the increase in admissions. Adaptive measures will become more important in the future, as summer heat stress is likely to intensify according to climate-change scenarios.