OA pain increases with depression
Although the effects of depression on OA knee pain do not change over time, depression persistence can significantly increase the severity of that pain, according to findings published in Arthritis Care and Research.
“Indeed, the association between symptoms of depression and pain among individuals with knee OA has been well replicated in the research literature,” Alan M. Rathbun, PhD, MPH, of the University of Maryland School of Medicine, in Baltimore, told Healio Rheumatology. “Studies have shown that pain is associated with the onset and severity of depressive symptoms, and conversely, the presence of depressed mood predicts more intense OA pain. However, prior studies have not recognized that the presence of depressive symptoms may cumulatively affect OA pain, where greater depression persistence could lead to more severe pain.”
To analyze how depression can affect OA knee pain, the researchers examined the dynamic associations between depressive symptoms and pain in 2,287 adults included in the Osteoarthritis Initiative, a longitudinal study of knee health, over a period of 48 months. The researchers assessed depressive symptoms during annual visits using the Center for Epidemiologic Studies Depression Scale. They measured OA knee pain with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale, which the researchers rescaled to range from 0 to 100.
According to the researchers, depressive symptoms did not correlate with future greater OA knee pain. The causal mean differences in WOMAC pain score, which compared depressed patients with those who were not depressed, ranged from 1.78 (95% CI, −0.73 to 4.30) to 2.58 (95% CI, 0.23 to 4.93) within years 1 and 4. Further, the depressive symptoms were not statistically significant (P = .94) by time interaction.
However, the researchers noted a statistically significant dose-response relationship between the depression persistence and OA knee pain severity (P = .002). Causal mean differences in WOMAC pain score were 0.89 (95% CI, −0.17 to 1.96) for 1 visit with depressive symptoms, 2.35 (95% CI, 0.64 to 4.06) for 2 visits and 3.57 (95% CI, 0.43 to 6.71) for 3 visits.
“Given depression is a modifiable factor, if it contributes to the development and severity of pain in OA patients, then treating this comorbidity may not only improve general quality of life but also OA symptoms,” Rathbun said. “This is likely why newer clinical care guidelines for OA patients recommend treating depression in this population, but unfortunately, prior studies indicate that depressive symptoms are under-recognized and under-treated in this group. Ultimately, these findings highlight the need for alternative disease management strategies for OA patients that incorporate effective interventions for depression that can be implemented in routine clinical practice.” – by Jason Laday
Disclosure: The researchers report funding from a National Institute on Aging training grant.