Depression often accompanies chronic pain, but the two conditions may best be treated separately, a study in May's Arthritis & Rheumatism shows.
The study centered on people with fibromyalgia -- a syndrome characterized by a history of chronic, widespread pain and tenderness to touch. Many of these patients also may suffer from depression.
"There is an incorrect impression among many doctors that if you treat a patient's depression, it will make their pain better. Not so," says researcher Daniel J. Clauw, MD, in a news release.
"If someone has pain and depression, you have to treat both," says Clauw. He is a rheumatology professor at the University of Michigan and the director of the University of Michigan's Chronic Pain and Fatigue Research Center.
It's possible that the findings could apply to other patients with chronic pain conditions, the news release notes. However, the study only looked at chronic pain and depression with fibromyalgia. They show that brain regions activated by pain are different from those activated by depression.
Finding From Fibromyalgia Study
Clauw's study tracked depression and pain in 33 women and 20 men diagnosed with fibromyalgia and 42 people who did not have fibromyalgia.
Researchers scanned participants' brain activity in regions that process pain sensation.
The findings showed that the existence or level of depression in people with fibromyalgia did not modulate pain sensation. In other words, the magnitude of pain was only weakly associated with self-reported depression.
However, depression was associated with the level of activity in brain regions that process the emotional aspects of pain.
Clauw and colleagues say their results are consistent with the findings of a number of other studies.
"We have seen that if you give antidepressants to the average patient with fibromyalgia, they'll come back a couple of months later and say, 'My pain isn't' any better, but I don't feel so sad about it,'" says Clauw in the news release.
"Our research provides further evidence that these pathways are quite independent," he says.
"Much has been made of the overlap and similarities between pain and symptoms of depression, but these and other data suggest it is also important to identify pain processing mechanisms that are independent of mood," write the researchers.
The study did not involve prescribing antidepressants for participants.
Widespread Problems; Help Is Available
Depression is extremely common in the U.S., affecting nearly 19 million adults (or 9.5 percent of the population) per year, says the National Institute of Mental Health. Not all of those people also have chronic pain.
"Major depressive disorder is often found in conjunction with chronic pain, with a prevalence of 30 percent-54 percent among tertiary care patients," write researchers.
Depression can be treated, and chronic pain can be managed. Asking for help is the first step; resources include doctors and mental health professionals.
By Miranda Hitti, review by Brunilda Nazario, MD
SOURCES: Giesecke, T. Arthritis & Rheumatism, May 2005; vol 52: pp 1577-1584. News release, University of Michigan. National Institute of Mental Health, "Depression." WebMD Medical Reference from Healthwise: "Chronic Pain - Treatment Overview." News release, John Wiley & Sons.