Placebo Effect Might Predict Response to Antidepressants
By Robert Preidt
WEDNESDAY, Sept. 30, 2015 (HealthDay News) — People with depression who show improvement when taking fake drugs get the greatest benefit from real medications, a new study finds.
It appears that patients who can use their brain’s own chemical forces to fight depression get more benefit when taking antidepressants than those who lack that ability, the University of Michigan Medical School researchers found.
“We need to find out how to enhance the natural resiliency that some people appear to have,” said research team leader Dr. Jon-Kar Zubieta, a former Michigan faculty member who is now at the University of Utah.
The findings could help explain why responses to medications vary among depression patients and help lead to new treatments, he and his colleagues said.
For the study, 35 people with untreated major depression were told they were receiving a new depression drug before receiving existing depression drugs. But the first drug was actually a placebo, or fake medication.
Patients who had the most improvement when taking the placebo showed the strongest response in brain regions involved in emotion and depression. These patients were also more likely to have fewer depression symptoms when they took the real drug.
The study was published online Sept. 30 in the journal JAMA Psychiatry.
The results provide objective evidence that the brain’s own opioid system responds to both antidepressants and placebos, and that variation in this response is associated with variation in symptom relief, said first author Dr. Marta Pecina, a research assistant professor in Michigan’s department of psychiatry.
“This finding gives us a biomarker for treatment response in depression — an objective way to measure neurochemical compounds involved in response,” she said in a university news release. “We can envision that by enhancing placebo effects, we might be able to develop faster-acting or better antidepressants.”
Zubieta said the study results suggest that some people are more responsive to the intention to treat their depression. They “may do better if psychotherapies or cognitive therapies that enhance the clinician-patient relationship are incorporated into their care as well as antidepressant medications,” he said in the news release.
The “placebo effect” noted in the study came not only from patients’ belief that they were receiving a real drug, Zubieta said, but also from simply being in a treatment environment.