Asthma caused an average of 467,000 hospitalizations per year between 1995 and 2002. Most asthma hospitalizations are preceded by an emergency department visit (Emergency Medicine Network; unpublished data), and asthma accounts for a total of nearly 1.8 million emergency department visits per year. Although exact figures are not available, many of these emergency asthma visits are preventable. Since a prior asthma hospitalization or emergency department visit is the strongest risk factor for subsequent emergency hospital utiliza-tion, follow-up after an asthma hospitalization or emergency department visit presents a golden opportunity for tertiary prevention. However, there are substantial knowledge gaps regarding the type of follow-up that will significantly improve asthma outcomes.
Two randomized controlled studies have shown that achieving a primary care follow-up visit after an asthma emergency department visit can be facilitated but may not significantly improve asthma outcomes. Another nonrandomized controlled study also showed that reminder phone calls after an emergency department visit could increase primary care physician follow-up office visits, but this improved follow-up was not associated with a significant decrease in subsequent emergency hospital care or improved asthma control scores over the next 12 months. In addition, a large survey of patients presenting to the emergency department with acute asthma showed that frequency of emergency department visits in the prior year was not related to having a primary care provider. so
This is not necessarily an indictment of primary care. Most patients who are followed up in primary care presumably do not require emergency hospital care. However, those who do require it apparently require something more than a return to primary care to significantly improve outcomes.
Several clinical trials have suggested that specialist follow-up may be more successful at preventing subsequent asthma hospitalizations than primary care follow-up. Mayo et al studied 104 adult asthmatic patients who had previously been admitted to the hospital due to asthma. Forty-seven patients were randomly assigned to an intensive outpatient treatment program in the chest clinic, and 57 patients continued to receive their previous outpatient care. Intervention patients required one third the number of hospital admissions per patient (p < 0.004) compared to usual-care patients, Hughes et al studied 95 children and adolescents who had been admitted with a diagnosis of asthma in the prior 5 years.