To examine the effect of cost-sharing on the use of asthma medications in asthmatic children. According to asthma guidelines, children with asthma may require treatment with multiple medications, including controllers and relievers, to achieve optimal control. Although families may be enrolled in drug benefit plans, impediments to access persist in the form of cost-sharing.
Population-based retrospective cohort study of children by analysis of administrative medication insurance claims data.
A cohort of 17 046 Ontario children with asthma enrolled in private drug plans. Main Exposure We used data on out-of-pocket expenses and reimbursement for medications to classify children as having zero, low ( or = 20%) levels of cost-sharing.
We examined use of bronchodilators, inhaled corticosteroids, leukotriene receptor antagonists, oral corticosteroids, and combination agents. Multiple linear and logistic regressions compared medication use between cost-sharing groups, controlling for age and sex.
The annual number of asthma medication claims per child was significantly lower in the high cost-sharing group (6.6) compared with the zero (7.0) and low (7.2) cost-sharing groups (P