Lower levels of physical performance and more severe disease are associated with higher levels of depression in knee osteoarthritis patients, according to new research presented June 14 at the Annual European Congress of Rheumatology in Amsterdam.

Although depressive symptoms affect one in five patients — twice the rate in the general public — and psychological factors are known to play a large role in osteoarthritis patients’ pain and physical function, rheumatologists tend to under-diagnose and undertreat depression, according to a EULAR press release.

“Given the results of our study, we believe that to effectively treat individuals with radiographic
knee OA and comorbid depressive disorder, it is necessary to use a combined treatment
strategy of two interventions delivered in parallel to simultaneously target each condition,” said
Alan Rathbun, of University of Maryland School of Medicine, in the release.

Rathbun and colleagues examined three factors that predict severity of osteoarthritis:

  1. structural severity, or the width of joint space
  2. physical performance, or walking speed
  3. pain, which was measured using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index

The study examined more than 1,650 patients and found that all three factors were associated with higher levels of depression. “Findings demonstrate that the presence of greater structural disease severity and pain and decreased physical performance increases the risk of depression onset among individuals with radiographic knee OA,” the authors wrote. “Thus, it is necessary to also intervene on osteoarthritis disease severity when treating depression to effectively manage these patients. A combined treatment strategy consisting of two interventions delivered in parallel to simultaneously treat each condition may be the most effective form of medical care for OA patients who have comorbid depression.”