Introduction

This chapter is based on an expanded manuscript submitted February 1992 to the Agency for Health Care Policy and Research Panel on Diagnosis and Treatment of Depressed Outpatients in Primary Care Settings (A. J. Rush, M.D., Chair).

Both drugs and psychotherapy have a role to play in the treatment of mood disorders (Depression Guideline Panel 1993). Pharmacotherapy has been shown to be effective in literally hundreds of placebo-controlled trials and represents the current standard of treatment for both depression and mania (American Psychiatric Association 1993; D. F. Klein et al. 1980). Psychotherapy is widely practiced but is less intensively studied. It has fared well in direct comparisons with pharmacotherapy, particularly the newer approaches tailored specifically for depressed populations.

Given the apparent efficacy of both drugs and psychotherapy, it is hardly surprising that the two are sometimes combined. Both biological and psychosocial factors have been implicated in the etiology of the mood disorders. As a consequence, it is often presumed that distinct subtypes of mood disorders exist that are differentially responsive to the two types of interventions. Moreover, it is generally assumed that each works through a different set of mechanisms, although this is by no means certain. Concerns among advocates for each approach that combined treatment would undercut the efficacy of their preferred modality have proved to be largely unfounded, and many patients are now treated with a combination of drugs and psychotherapy.

Nonetheless, it is not clear that combined treatment is necessary, or even desirable, in most cases. The clinical practice guidelines published by the Agency for Health Care Policy and Research (AHCPR) recommend against the routine use of both medication and a formal psychotherapy as the initial treatment for most patients (Depression Guideline Panel 1993). They suggest that patients with milder, more transient depressions may not require or respond to medications and therefore need not be exposed to their side effects and risks. Conversely, they also suggest that many patients with more severe illnesses will remit with pharmacotherapy alone and therefore need not bear the additional time and expense of psychotherapy. The guidelines further suggest that combined treatment be restricted to instances in which either single modality has been only partially effective, multiple targets exist that are differentially affected by drugs and psychotherapy, or the prior course of illness is chronic.

Our own sense is that these guidelines are fairly sensible but unduly restrictive. There are at least four ways that combined treatment can prove superior to either single modality (Hollon et al. 1991b). First, combined treatment might increase the magnitude of response shown by any given patient. That is, some patients might do better in combined treatment than they would with either drugs or psychotherapy alone. For example, a recent multisite trial found that the combination of drugs and psychotherapy was more effective than either single modality alone in the treatment of patients with chronic major depression (Keller et al. 2000). Few studies suggest such a clear advantage for combined treatment in nonchronic samples, but there is reason to think that this literature may have been insufficiently sensitive to detect any such effect.

Second, combined treatment might increase the probability of response. That is, if some patients are responsive only to medications and other patients only to psychotherapy, then providing both modalities in combination will increase the likelihood that each patient will receive and take part in something to which he or she will respond. This is clearly what the authors of the AHCPR guidelines had in mind when they recommended adding the second modality when the first was insufficient. Given our relative inability to predict who will respond to which modality and given the difficulties inherent in executing each modality in an optimal fashion, a case can be made for starting both simultaneously for most patients.

Third, combined treatment might enhance the breadth of response. That is, to the extent that each single modality affects different types of outcomes, combined treatment might retain the unique advantages associated with each, producing a superior overall pattern of response relative to either modality alone. This is clearly what the authors of the AHCPR guidelines had in mind when they suggested that combined treatment be considered in cases in which clinical circumstances suggest two discrete targets of therapy. Our own sense is that this is more likely to be the case than not.

Finally, combined treatment might enhance the acceptability of treatment relative to either modality alone. For example, adding psychotherapy may make patients more willing to accept medications or tolerate their side effects. Even simple patient education appears to enhance compliance, and more complex strategies may help deal with biases or misconceptions (Basco and Rush 1995). Similarly, adding medications to psychotherapy may speed or enhance response, making patients more amenable to self-exploration. In either event, such effects are likely to manifest themselves in greater compliance and reduced attrition, or they may enhance the probability of response among all patients treated.

Check also:
Antidepressant and Antimanic Medications
Depression-Focused Psychotherapies
Psychodynamic Psychotherapies
Combined Medication and Psychotherapy
Electroconvulsive Therapy
Light Therapy
Treatment-Resistant Mood Disorders
Treatment of Mood Disorders in the Medically Ill Patient
Strategies and Tactics in the Treatment of Depression