The Association Between Medical Comorbidity and Psychotherapy Processes and Outcomes for Major Depressive Disorder in a Community Mental Health Setting

Many individuals seeking mental health services for depression often suffer from a comorbid medical condition. The goal of the present study was to assess the presence of medical comorbidity in a community mental health center setting that primarily serves a Medicare and Medicaid population, characterize the types of comorbid medical conditions experienced in this setting, and explore the association between medical conditions on the alliance, attrition from services, and outcome. Medical diagnoses were collected from patient charts and structured clinical interviews from 353 participants who had a baseline assessment as part of a comparative effectiveness study of cognitive and dynamic therapies for major depressive disorder. We calculated the Charlson Comorbidity Index and the number of total medical diagnoses for each patient. Results from this study revealed that a high percentage of patients in this setting experienced a comorbid medical condition. No significant associations were found between the number of medical conditions or the Charlson Comorbidity Index and the alliance. No significant relationship was found between the number of medical conditions or the Charlson Comorbidity Index and early attrition from treatment or treatment outcome. However, exploratory analyses found that presence of a nervous system disorder was associated with relatively poorer treatment outcomes after initial engagement. Implications of these findings are discussed. Treatments for major depressive disorder may benefit from addressing the impact of medical disorders on physical functioning. Clinical Impact StatementQuestion: This article sought to determine the level of medical burden experienced by individuals seeking services for major depressive disorder within a community mental health setting and explore the relationship between medical burden and psychotherapy processes, outcome, and attrition. Findings: There is a high level of comorbidity between major depressive disorder and medical illnesses in the community mental health setting; however, medical burden is not significantly related to psychotherapy processes. Meaning: Clinicians and medical providers may benefit from addressing medical illnesses and comorbid mental health diagnoses through integrated care. Next Steps: Additional research should be conducted to confirm and explore the impact of specific medical diagnoses on psychotherapy processes and outcome.