Costs and associated factors with optimal and suboptimal responses to the treatment of major depressive disorder

To evaluate the compliance, persistence and costs of the treatment of major depressive disorder (MDD) in the setting of Primary Care, placing emphasis on the different aspects of those patients with an initial suboptimal response to antidepressant treatment. A retrospective observational study using the population registers of Badalona Healthcare Services. The inclusion criteria consisted of; age ≥18 years, initial episode during 2008-2009, and to be on antidepressant treatment for at least 8 weeks after the first prescription. The follow-up was 12 months. Two study groups were formed, patients with suboptimal response, and remission. Sociodemographic data, compliance and adherence to treatment, health costs (direct and indirect). A total of 2,260 subjects were analysed (mean age 58.8 years, 74% women). Just under half (42.7%, 95% CI; 40.0-46.4%) had a suboptimal response to the treatment. These patients had a higher mean age, a higher proportion of women, and pensioners, as well as higher comorbidity, compared to the remission group. They also had poorer compliance percentages (65.1% vs. 67.7%) and treatment persistence at 12 months (31.8% vs. 53.2%), respectively, P