Continuing the discussion from the last post, the University of Pennsylvania study (1) concluded that anti-depressant medication (ADM) was no better than placebo (sugar pill) for people with mild, moderate or even severe depression as measured by the Hamilton Depression Rating Scale. Only in those with very severe depression by that scale was the improvement with ADM significantly greater than the improvement with placebo.
This research presents several issues for clinicians and patients to consider. First, the six studies used patients with recent depression. Results with long-standing (chronic) depression may be different. Second, the studies used only two of the many available ADMs (specifically paroxetine and imipramine). Results with other drugs may differ though the two drugs used in this research are representative of the two largest classes of ADMs on the market.
Third, depressed patients generally improve with placebo. If a clinician prescribes an ADM to a patient with less than very severe depression they will likely improve, not due to the effect of the drug but because of the placebo effect. Should clinicians stop prescribing ADMs to patients with less than very severe depression even though it is likely they will benefit? This is an ethical dilemma because the placebo effect depends on the patient’s belief in the effectiveness of the drug. To get this effect, the clinician must withhold information from the patient about the lack of drug effect in people whose depression is less than very severe. This would risk the patient’s trust not only in their personal clinician but with the health care profession generally. That is why I do not prescribe a medication (of any type) unless there is reason to believe the benefit is greater than placebo.
To be continued…
1. Fournier JC et al. Antidepressant drug effects and depression severity: a patient-level meta-analysis. JAMA. 303(1):47-53, 2010 Jan 6.