Wise said that part of the study's strength is that it gauged individuals' perceptions of their pain intensity at different times, as well as comparing different participants' pain experiences.

"Pain is difficult to study in part because experiences and reporting of pain differ from one person to another. There can be differences in people's central or peripheral nervous systems, past experiences of pain or cultural differences in perceptions of pain, and these make it very complicated to look at differences in pain across individuals. Our study design helped eliminate some of those obstacles," he said. "But it's likely that people's pain is the result of a large group of different factors rather than something as simple as one specific physiological factor."

While the study did not measure whether participants suffered from clinical conditions like depression, it suggests that mental-health treatment could improve patients' osteoarthritis pain - especially because there are no medications that have been proven effective for changing the overall course of osteoarthritis. Current treatments for osteoarthritis include weight loss, improved diet, vitamin consumption and over-the-counter analgesics like acetaminophen or ibuprofen.

"With the paucity of effective interventions for osteoarthritis pain and the toxicities of some in common use, mental health may represent a new therapeutic target for osteoarthritic pain, with potential significant opportunities for both patients and physicians," the study says.

Source: University of California - Davis - Health System