A retrospective study of the mortality and death-related risk factors of patients hospitalized for asthma exacerbation in Chinese urban areas

Abstract

Objective: To study the mortality and death-related risk factors of patients hospitalized for asthma exacerbation in Chinese urban areas. Methods: A retrospective study was carried out in 29 hospitals of 29 provinces throughout mainland China. Patients hospitalized for asthma exacerbation during 2013-2014 in each hospital were included. For each patient, information about demography, admission time, comorbidities, severity of diseases, intense care unit (ICU) admission, use of mechanical ventilation and the outcome was obtained. The mortality of patients hospitalized for asthma exacerbation was calculated, and the basic information and causes of death of the patients who died were summarized. The death-related risk factors and numbers of comorbidities were compared between the patients who survived and those who died during hospitalization. Results: A total of 3 240 patients (median age 57.0) were included and among them 8 patients (median age 68.5) died. The mortality of patients hospitalized for asthma exacerbation was 0.25%. All the patients who died were admitted during the winter and spring. One patient died of acute myocardial infarction, one of cardiac shock, one of tension pneumothorax, one of sudden death, one of respiratory failure and three of unknown causes. The average number of comorbidities of patients who died was 1.10, larger than that of patients who survived (0.83) (P>0.05). More patients had diabetes, coronary artery diseases and hypertension as comorbidities in the patients who died (2/8) than those who survived[7.6% (246/3 232), 7.6% (246/3 232), 22.6% (731/3 232), respectively](all P>0.05). Conclusions: The in-hospital mortality of patients hospitalized for asthma exacerbation of China in this study is low. The patients who died are much older, and with more comorbidities, and a higher percentage of comorbidities such as diabetes, coronary artery diseases, and hypertension.