NEW YORK — New research shows drugs that treat depression, OCD and anxiety can also help people with chronic pain or other chronic conditions.
The new study was published online in the journal Science Translational Medicine.
“Depression is one of the leading causes of disability in the U.S. today and is also a leading cause of death,” said Dr. David Siegel, the study’s lead author and associate professor of psychiatry at the University of California, San Francisco.
“With a simple course of medication, these conditions can be effectively managed and treated.
And this work will help people live longer lives.”
The study, led by Dr. Andrew H. Fiedler, an assistant professor of medicine at the Medical College of Wisconsin-Madison, looked at patients with chronic noncancer pain who had been prescribed the selective serotonin reuptake inhibitors (SSRIs) metformin and bupropion.
The drugs act on receptors in the brain and body that regulate the neurotransmitters serotonin and norepinephrine.
The study was conducted in collaboration with the Centers for Disease Control and Prevention (CDC) and the University Health Network, both of which are supported by grants from the National Institutes of Health (NIH).
Researchers took the medications at the beginning of each person’s treatment and compared their results to those of a control group who did not have medication.
The researchers measured changes in brain blood flow, levels of the hormone corticosterone, and the amount of oxytocin — a hormone that is released in the body when a person feels love and support.
The researchers then used brain imaging to measure brain activity as people looked at pictures of people with depression, and as they looked at a picture of a patient who had a chronic pain condition.
“We knew that people with mild depression are often more depressed than people with moderate or severe depression,” said Fiedlers team leader Dr. Eric Wojcik.
“But we didn’t know how depression might manifest itself.”
“Our data shows that people who take SSRIs have lower levels of corticotropin-releasing hormone (CRH), which is a hormone associated with the release of the neurotransmitter oxytocine,” Wojcek said.
“The CRH release is what causes people to feel happy and supportive.”
The researchers also measured changes of brain activity in the patients and the control group, including brain activity that occurs when they look at pictures depicting people with different levels of depression.
The patients who took SSRIS had lower levels in the anterior cingulate cortex (ACC) and a smaller hippocampus, areas of the brain involved in processing emotions.
And they had smaller amygdala, which is part of the reward system, compared with the control subjects.
Researchers also found that patients taking SSRis had lower brain activity on brain imaging, including the PET scans, than those who did have the disease.
These patients also had less oxygen and less blood flow to the brain.
The team said the findings were consistent with previous research.
The results also support previous studies showing that antidepressants are effective in reducing depression in people with major depression, according to Wojcick.
“Our results are important for the future of this field because it gives us a more reliable and realistic measure of depression and anxiety,” Wajcik said in a press release.
“The idea that depression is associated with inflammation and that medications are helpful in controlling inflammation is a new concept,” said Siegel.
“We now know that antidepressants work by blocking the inflammatory processes that lead to depression and other mental disorders.
We now know they also have positive effects in terms of reducing anxiety, reducing depression and reducing pain.”
Patients taking the SSRI medications also had higher levels of oxycodone, which the team noted has been used to treat chronic pain in people for more than 30 years.
The findings suggest that drugs can be useful in treating depression and inflammation, Wojczks research team said.
The research was supported by the National Institute on Drug Abuse (grant R01 DA032492).