Subject:
Patient Preference

Short Description:
Patient Preference Not a Good Predictor of Treatment Response

Background:

Do patients with major depressive disorder (MDD) respond better when psychiatrists offer the type of treatment—medication or psychotherapy—that the patient prefers? And do patients’ beliefs about what causes their depression influence treatment outcomes? In a new study, researchers concluded that, despite their expectations, neither factor is a good predictor of treatment response.

Researchers looked at 80 patients who participated in a 12-week randomized, double-blind clinical trial of MDD. They assessed the patients’ treatment preference, the strength of that preference, and their beliefs about the causes of their depression before the subjects entered into the clinical trial. The majority (45 patients) expressed a preference for one of the two types of treatment, but all were randomly assigned to receive either 16 sessions of cognitive behavioral therapy (CBT) or a daily dose of the antidepressant escitalopram (Lexapro).

The researchers measured response by three commonly used rating scales. Contrary to the researchers’ hypothesis, neither patients’ preferences, nor the strength of that preference, influenced remission rates at the end of the 16-week trial. Furthermore, patients who did not receive their preferred treatment were no more likely to drop out of the trial than others.

The researchers also expected to find that remission rates would be greater when patients believed the cause of their depression matched the underlying mechanism of their assigned treatment. For instance, patients who believe that depression is a biochemical disorder might respond better to an antidepressant medication. However, there was no correlation between individual beliefs about the origin of their depression and remission based on treatment type.

One limitation of the study was a moderate sample size. Another was the fact that researchers did not ask about negative attitudes towards treatment, only “preferences.” It’s quite possible that critical attitudes toward medication-based approaches, or particularly bad experiences with therapy or medications in the past, might result in poorer outcomes. However, even if such strong beliefs existed, most (81%) patients remained in the trial for the full 16 weeks (Dunlop B et al, J Psychiat Res 2012;46(3):375–381).

TCPR's Take:
Past studies have produced mixed results when it comes to the question of whether patients do better when offered the treatment option they prefer (see Swift JK et al, J Clin Psychol2009;65(4):368–381). One study (Mergl R et al, Psychother Psychosom 2011;80(1):39–47) covered in the February 2011 issue of TCPR, compared SSRI versus group therapy for patients with minor depression, and found that no one who expressed a preference for sertraline (Zoloft) remitted with psychotherapy. Several other studies have found the opposite. It’s possible that patient preference is actually a surrogate marker for some other predictor, like a personality factor (eg, inhibition in social settings) or past experience with either meds or therapy. A limitation in all randomized studies comparing highly different treatment methods is that patients with the strongest preferences about treatment are typically not included or simply choose not to participate.