Severe asthma exacerbation:Changes in patient characteristics,management,and outcomes from 1997 to 2016 in 40 ICUs in the greater Paris area

Background Despite advances in asthma treatments,severe asthma exacerbation(SAE)remains a life-threatening condition in adults,and there is a lack of data derived from adult patients admitted to intensive care units(ICUs)for SAE.The current study investigated changes in adult patient characteristics,management,and outcomes of SAE over a 20-year period in 40 ICUs in the greater Paris area.Methods In this retrospective observational study,admissions to 40 ICUs in the greater Paris area for SAE from January 1,1997,to December 31,2016 were analyzed.The primary outcome was the proportion of ICU admissions for SAE during 5-year periods.Secondary outcomes were ICU and hospital mortality,and the use of mechanical ventilation and catecholamine.Multivariate analysis was performed to assess factors associated with ICU mortality.Results A total of 7049 admissions for SAE were recorded.For each 5-year period,the proportion decreased over time,with SAE accounting for 2.84%of total ICU admissions(n=2841)between 1997 and 2001,1.76%(n=1717)between 2002 and 2006,1.05%(n=965)between 2007 and 2011,and 1.05%(n=1526)between 2012 and 2016.The median age was 46 years(interquartile range[IQR]:32–59 years),55.41%were female,the median Simplified Acute Physiology Score II was 20(IQR:13–28),and 19.76%had mechanical ventilation.The use of mechanical ventilation remained infrequent throughout the 20-year period,whereas the use of catecholamine decreased.ICU and hospital mortality rates decreased.Factors associated with ICU mortality were renal replacement therapy,catecholamine,cardiac arrest,pneumothorax,acute respiratory distress syndrome,sepsis,and invasive mechanical ventilation(IMV).Non-survivors were older,had more severe symptoms,and were more likely to have received IMV.Conclusion ICU admission for SAE remains uncommon,and the proportion of cases decreased over time.Despite a slight increase in symptom severity during a 20-year period,ICU and hospital mortality decreased.Patients requiring IMV had a higher mortality rate.

Current asthma control predicts future risk of asthma exacerbation： a 12-month prospective cohort study

Background The performance of asthma control test （ACT） at baseline for predicting future risk of asthma exacerbation has not been previously demonstrated. This study was designed to explore the ability of the baseline ACT score to predict future risk of asthma exacerbation during a 12-month follow-up. Methods This post hoc analysis included data from a 12-month prospective cohort study in patients with asthma （n=290）. The time to the first asthma exacerbation was analyzed and the association between baseline ACT scores and future risk of asthma exacerbation was calculated as adjusted odds ratio （OR） using Logistic regression models. Further, sensitivity and specificity were estimated at each cut-point of ACT scores for predicting asthma exacerbations. Results The subjects were divided into three groups, which were uncontrolled （U, n=128）, partly-controlled （PC, n=111）, and well controlled （C, n=51） asthma. After adjustment, the decreased ACT scores at baseline in the U and PC groups were associated with an increased probability of asthma exacerbations （OR 3.65 and OR 5.75, respectively）, unplanned visits （OR 8.03 and OR 8.21, respectively） and emergency visits （OR 20.00 and OR 22.60, respectively） over a 12-month follow-up period. The time to the first asthma exacerbation was shorter in the groups with U and PC asthma （all P 〈0.05）. The baseline ACT of 20 identified as the cut-point for screening the patients at high risk of asthma exacerbations had an increased sensitivity of over 90.0% but a lower specificity of about 30.0%. Conclusion Our findings indicate that the baseline ACT score with a high sensitivity could rule out patients at low risk of asthma exacerbations and predict future risk of asthma exacerbations in clinical practice.