Antidepressants work for patients with comorbidities

Patients with comorbidities can be safely and effectively treated for major depressive disorder (MDD) with antidepressants, even combination therapy, with no more adverse effects than their healthier counterparts, researchers concluded.

The Combining Medications to Enhance Depression Outcomes (CO-MED) trial consisted of 12 weeks of acute care and 16 weeks of follow-up treatment. It was a multisite, single-blind, randomized trial that compared the efficacy of traditional selective serotonin reuptake inhibitor (SSRI) monotherapy (escitalopram plus placebo) versus that of two antidepressant medication combinations (escitalopram plus bupropion-SR, and venlafaxine-XR plus mirtazapine) in patients with chronic and/or recurrent, nonpsychotic MDD. Clinicians were not blinded to maximize safety and to allow them to make informed flexible dosing decisions.

Patients underwent the Self-Administered Comorbidity Questionnaire, a self-report that assesses the presence of medical problems, their severity, and whether the condition limits functioning. Conditions on the questionnaire included heart disease, high blood pressure, lung disease, diabetes, gastrointestinal tract disorders, kidney disease, liver disease, anemia or other blood disease, cancer, arthritis, thyroid disease, and chronic back pain. Also, respondents could add three more conditions.

At 12 and 28 weeks, researchers compared unadjusted and adjusted outcomes (symptom severity, tolerability and functioning) among patients with none, one, two, and three or more general medical conditions. Results appeared in the January/February Annals of Family Medicine.

Of the 665 evaluable patients, 328 (49.5%) reported having no general medical conditions, 158 (23.8%) reported having one condition, 98 (14.8%) reported having two conditions and 79 (11.9%) reported having at least three conditions. (Two participants did not complete the questionnaire.)

There were no differences in outcomes associated with antidepressant monotherapy and either of the antidepressant combination therapies, regardless of the number of general medical conditions a patient had. Specifically, within each group having a given number of conditions, the three treatments did not differ significantly by efficacy or tolerability at weeks 12 and 28.

The authors concluded that the almost complete lack of difference among patients with differing numbers of conditions shows that all patients can receive equally safe and effective treatment for MDD with antidepressants without risk of additional adverse effects or intolerability. Combination antidepressant therapy had no additional benefit over SSRI monotherapy for patients with general medical conditions and comorbid, chronic or recurrent MDD.

“Not surprisingly, participants with general medical conditions and comorbid MDD were more likely to be treated for depression by their primary care physician than a psychiatric care professional,” the authors wrote. “This greater likelihood of treatment in primary care could occur for a variety of reasons, the most obvious being that patients with general medical conditions and comorbid MDD may prefer to be treated by a single physician rather than use a separate mental health professional for their depression.”