Depression could make symptoms of knee osteoarthritis, or OA, feel even worse. In fact, a study published in The Journal of Bone and Joint Surgerysays depression can have just as strong an effect on knee pain as physical damage.
“This was found to be particularly true in patients with radiographic findings of less severe – mild to moderate – knee osteoarthritis,” says lead author Tae Kyun Kim, MD, PhD, director of the division of knee surgery and sports medicine at the Joint Reconstruction Center at Seoul National University Bundang Hospital in South Korea.
Dr. Kim’s research team studied data taken between 2005 and 2006 from 660 Korean men and women older than age of 65. They measured the severity of participant’s OA damage with X-rays, questioned patients about their pain and interviewed them to diagnose depressive disorders. Those with the most joint damage reported feeling the most pain, but more surprising was that patients with mild to moderate knee OA who were experiencing depression also reported severe pain, even if X-rays didn’t show the significant damage that typically indicates pain.
“Pain is a complex phenomenon which is influenced by many factors, including several physical and psychological factors,” Dr. Kim explains. “Concurrent pain and depression have a much greater impact than either disorder alone on multiple domains of functional status.”
Researchers say their findings highlight the need for doctors to be on the lookout for depression in their knee OA patients.
“We believe that one simple and practical option for an orthopeadic clinic would be to establish a consultation system with relevant psychiatrists who can identify and treat depression, if found, in patients who continue to complain of severe symptoms that are discordant with the radiographic severity of knee osteoarthritis and who do not respond to treatment modalities,” Dr. Kim suggests.
Jon T. Giles, MD, an assistant professor of medicine at Columbia University and rheumatologist at New York Presbyterian Hospital in New York City, says this study adds further weight to the existing medical literature highlighting the effect of psychosocial issues on pain responses.
“Painful sensations are relayed through the brain in a very complex way, and can be modulated up or down,” he says. With stress, poor sleep, anxiety and depression, which are known to influence pain levels, “stimuli feel more painful than they would in someone without the adverse psychosocial factors. This probably explains in part why the largest effect of depression in the study was seen in those without much OA to see on X-rays.”
Because depression might amplify pain responses in OA and other musculoskeletal conditions, Dr. Giles says, clinicians should use antidepressants and other treatments if necessary to alter mood, rather than just prescribing medications designed to block pain.
“Antidepressant medications have been found to have analgesic as well as antidepressant effects,” agrees Dr. Kim.
Dr. Giles says it’s also important for caregivers who treat musculoskeletal conditions to screen patients for potential psychological aggravators of pain and refer them for treatment when needed.