Association of treatment modality for depression and burden of comorbid chronic illness in a nationally representative sample in the United States

Objective: We examined associations between treatment modality for depression and morbidity burden. We hypothesized that patients with higher numbers of co-occurring chronic illness would be more likely to receive recommended treatment for depression with both antidepressant medication and psychotherapy. Methods: Using a retrospective cross-sectional design, we analyzed data on 165,826 people over 16 years from 2004 to 2008. Using a single multinomial logistic regression model, we examined the likelihood of treatment modality for depression: no treatment, psychotherapy alone, medication alone, and psychotherapy and medication. We examined the following predictors of therapy: (a) morbidity burden; (b) five specific chronic conditions individually: diabetes mellitus 11, coronary artery disease, congestive heart failure, hypertension, and chronic obstructive pulmonary disease or asthma; and (c) sociodemographic factors. Results: The likelihood of any treatment for depression, specifically psychotherapy with medication, increased with the number of co-occurring illnesses. We did not find a clear pattern of association between the five specific conditions and treatment modality, although we identified treatment patterns associated with multiple sociodemographic factors. Conclusions: This study provides insight into the relationship between multimorbidity and treatment modalities which could prove helpful in developing implementation strategies for the dissemination of evidence-based approaches to depression care. (C) 2012 Elsevier Inc. All rights reserved.