Depression and cortisol stress responses in adults with rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint swelling and tenderness, chronic pain and fatigue, and high rates of disability. There is also evidence that individuals with RA exhibit higher rates of depression than their healthy peers. When present in individuals with RA, depressive symptoms have been associated with subjective symptom reports as well as more objective indices of disease activity. One plausible mechanism for the association between depressive symptoms and poor outcomes in RA is hypoactive hypothalamic-pituitary-adrenal (HPA) responses to stress. In the present study, 33 individuals (19 women, 14 men, mean age 59.79 years) with physician-verified RA completed the Hamilton Depression Inventory (HDI; Kobak & Reynolds, 1995) and participated in a laboratory stress protocol consisting of a speech task and a stressful interview. Salivary cortisol and perceived stress ratings were collected at baseline, after each stress task, and at recovery. The average HDI score in this sample (mean = 12.71, standard deviation = 5.82) fell below the clinical cutoff score of 19. Thus, participants in this study were not clinically depressed. Results of hierarchical linear modeling (HLM) revealed that, as predicted, individuals with elevated HDI scores exhibited reductions in baseline cortisol levels and less decline in cortisol levels across the laboratory session than individuals with lower levels of depressive symptoms. Thus, in individuals with RA, elevations in depressive symptoms are associated with a cortisol pattern conducive to inflammatory processes. These results are discussed within the context of clinical implications for RA.