One possible reason, he says, is that “with depression and chronic pain in general, we can’t get doctors to recognize that these stand alone; they are not just due to living with chronic illness.” Many doctors believe that being depressed or anxious just comes with living with a chronic disease. Instead of looking to see if depression may be a side effect of medication or due to another stressor, some may ignore the issue.

Dr. Clark also says that mental health issues are likely underreported by patients. The stigma that persists about psychological issues may keep patients from talking about it with their doctors at all. No one wants to be labeled as “crazy,” he says. And they may not make a connection between their pain and depression. 

But there is a complex relationship between mental health issues and disability, and they are strongly linked, Murphy says. Not diagnosing or treating one can impact the other greatly.

“People with mental health conditions definitely tend to have more functional limitations,” she says. Having depression may mean someone doesn’t have energy to exercise, and someone with anxiety may not work out because they are afraid to fall and make their pain worse, she adds.

According to the National Alliance on Mental Illness, or NAMI, someone who has depression and a chronic illness may be less likely to adhere to his treatment, and more likely to smoke, drink alcohol, eat poorly and neglect physical activity. All of these behaviors can all lead to poorer outcomes.

Because of the close relationship between treatment of mental health issues and improvements in pain and function, the study authors write, “Treating mental health conditions should be regarded as a fundamental part of managing arthritis symptoms.”

Antidepressants and anti-anxiety medications may help, but they aren’t the only treatment options, they write. Murphy recommends self-management classes for anxiety and depression, pointing out that a separate CDC study recently found that these classes were “associated with a considerable and sustained decrease in mental distress.”

Physical activity is another good option. Almost any kind of activity can help reduce pain and depression – and it’s essential for managing other arthritis symptoms, too. The study authors note that community-based physical activity programs, like EnhanceFitness and the Arthritis Foundation’s Walk With Ease program, are particularly good at helping people with arthritis exercise without worsening symptoms.

Murphy is hoping that simply increasing awareness of the link between arthritis and psychological issues will improve diagnosis and treatment over time.

“We’ve been aware of the physical implications, but less so of the emotional ones,” Murphy says. “There is an interaction across pain, anxiety and disability. By focusing on only one side, we are missing a whole other part of the picture.”