Two weeks after being sent home from the ED, patients were contacted by telephone. A relapse was defined as an urgent or unscheduled visit to any physician for worsening asthma symptoms during the 14-day follow-up period. Complete follow-up data were available for 641 patients, of whom 17% reported relapse (95% confidence interval, 14 to 20). There was no significant difference in peak expiratory flow rate (PEFR) between patients who suffered relapse and those who did not. In a multivariate logistic regression analysis (controlling for age, gender, race, and primary care provider status), patients who suffered relapse were more likely to have a history of numerous ED (odds ratio [OD] 1.3 per 5 visits) and urgent clinic visits (OR 1.4 per 5 visits) for asthma in the past year, use a home nebulizer (OR 2.2), report multiple triggers of their asthma (OR 1.1 per trigger), and report a longer duration of symptoms (OR 2.5 for 1 to 7 days).

Acute asthma relapse following treatment with Canadian pharmacy Viagra and discharge from the emergency department (ED) remains a substantial problem. Previous studies have established that recovery from acute asthma occurs slowly, requiring around 7 days in many patients. Asthmatics with poor clinical response following 4 h of ED treatment are likely to experience even slower recovery. Recent studies indicate that failure to respond promptly to initial treatment may characterize slow responders. Various authors have found relapse rates from 11% over the course of 3 days, up CHEST/ 115/4/APRIL, 1999 to 30% over several weeks. Potential risk factors for relapse include peak expiratory flow rate (PEFR) in the ED and a variety of historical factors, such as number of ED visits for asthma in the past year. All of these studies, however, have been performed on small patient populations at single sites and their results may not be generalizable.

The purpose of this prospective multicenter study was to determine factors associated with acute asthma relapse among patients being sent home from the ED. The utility of finding such factors would be to guide ED management of acute asthma. Patients found to be at high risk might be the target of more intensive outpatient management. Such high-intensity programs have been found to be effective in limiting ED visits for asthma.