ORIGINAL PAPER Economic factors in of patients’ nonadherence to antidepressant treatment Haekyung Jeon-Slaughter Received: 29 April 2011 / Accepted: 3 March 2012 / Published online: 14 March 2012 Ó Springer-Verlag 2012 Abstract Purpose Patients’ nonadherence to antidepressant treat- ment hampers cost and efficacy of depression-specific treatment. However, previous studies have failed to find consistent findings in economic effect on nonadherence and also failed to reach consensus in how to measure nonadherence to treatment. The study attempts to investi- gate income effect on nonadherence to selective serotonin reuptake inhibitors (SSRIs) treatment with clear definitions of nonadherence: self discontinuation of SSRIs (nonper- sistence) and under-dose of SSRIs (noncompliance). Methods The study extracted data from the National Comorbidity Survey-Replication (NCS-R). The study sample (n = 280) includes adults between the ages of 18 and 64 who were diagnosed with Diagnostic Statistics Manual IV Major Depressive Episode (MDE) at some point during their lifetime and medicated with SSRIs in the past 12 months. Results Just above poverty level of family income and no health insurance increased the risk of medication nonper- sistence in SSRIs treatment. The study findings confirmed that African Americans were at higher risk of medication noncompliance than Whites (odds ratio, 4.53) and MDE comorbidity was positively associated with medication noncompliance (odds ratio, 4.25). Conclusions Low income level, combined with health insurance status, and race/ethnicity, predict nonadherence to antidepressant treatment. The study findings would help physicians and hospitals developing interventional strategies and programs to increase patients’ adherence rates in anti- depressant treatment. Keywords Medication nonadherence Á Antidepressants Á Income Á Health insurance Introduction Approximately 27 million Americans, ages 6 years and older, were on antidepressants as of 2005 and the use of antidepressants has constantly increased in the past two decades [1–3]. This trend is partly due to the introduction of the second-generation antidepressants, mostly selective serotonin reuptake inhibitors (SSRIs) [1], which have bet- ter tolerability than the first-generation antidepressant, tri- cyclic antidepressants (TCAs) [4–7]. However, the effectiveness of antidepressant treatment, measured by remission of depressive symptoms and prevention of relapses, has been challenged by patients’ nonadherence to treatment recommendations [8–11]. Patients’ nonadher- ence to antidepressant treatment accounts for poor out- comes [12, 13] and cost ineffectiveness of the treatment [5, 14, 15]. Nonadherence to antidepressant treatment can be observed in two types of behaviors: self premature dis- continuation and taking less or more amounts of medica- tion than prescribed. Previous studies [16, 17] have suggested definitions and terminology to clearly distinguish self premature discontinuation of antidepressants from under- or over-dosing behavior. After carefully reviewing the existing literature on nonadherence in pharmacotherapy [16–22], this study used the terminology suggested by Cramer and colleagues [17] and Sawada and colleagues [16] to define self premature discontinuation of medication H. Jeon-Slaughter (&) Department of Psychiatry and Behavioral Sciences, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA e-mail: hattie-jeon-slaughter@ouhsc.edu 123 Soc Psychiatry Psychiatr Epidemiol (2012) 47:1985–1998 DOI 10.1007/s00127-012-0497-6