Objective: This article will address the effect of exacerbation status, disease severity (defined by medication required), and other variables on resource use and costs for asthma in Switzerland in 1996 to 1997.
Methods: A retrospective chart-based study was performed. A sample of 422 adults was analyzed. Target variables were stratified by disease severity and exacerbation status. Bivariate associations were assessed. Multiple linear regression was performed on the logarithm of direct medical costs.
Results: The probability of exacerbations was positively associated with disease severity. Resource use and costs were associated with both of these variables. Multiple linear regression identified age, presence of asthma-related comorbidities, degree of severity, exacerbation status, quick reliever versus controller therapy, and diagnosis or treatment by a pulmonologist as independent influences on direct costs. An interaction between severity and exacerbation status was also noted. Regression identified direct costs in the highest severity group to be 2.5 times higher than those in the lowest group, if there were no exacerbations. If exacerbations were present, costs were 5.7 times higher.
Conclusions: Because of its high prevalence, asthma has a high impact on public health. This impact depends on disease severity and, according to these findings, may also depend on the extent to which exacerbations are avoided or at least controlled.