Comparing treatment persistence, healthcare resource utilization, and costs in adult patients with major depressive disorder treated with escitalopram or citalopram

Major depressive disorder is the most common type of depression, affecting 6.6% of adults in the United States annually. Citalopram and escitalopram are common second-generation antidepressants used for the treatment of patients with this disorder. Because citalopram is available in generic forms that have lower acquisition costs compared with the branded escitalopram, some health plans may provide incentives to encourage the use of the generic option. Decisions based solely on drug acquisition costs may encourage the use of a therapy that is less cost-effective when treatment persistence, healthcare utilization, and overall costs are factored in. To compare, in a real-world setting, the treatment persistence, healthcare utilization, and overall costs of managing adult patients with major depressive disorder who are treated with escitalopram or citalopram. Administrative claims data (from January 1, 2003, to June 30, 2005) were analyzed for patients with major depressive disorder aged ≥18 years. Patients filled ≥1 prescriptions for citalopram or for escitalopram (first-fill time was defined as the index date) and had no second-generation antidepressant use during the 6-month preindex period. Treatment persistence, healthcare utilization, and healthcare costs were measured over the 6-month preindex and 6-month postindex periods and compared between patients treated with citalopram or escitalopram, using unadjusted and multivariate analyses. Patients receiving escitalopram (N = 10,465) were less likely to discontinue the treatment (hazard ratio 0.94; P = .005) and switch to another second-generation antidepressant (hazard ratio 0.83; P