Inflammation Associated With Depression in PsA
Although depression is known to be associated with psoriatic arthritis (PsA), new research indicates that depressed mood may be due to biological as well as emotional and sociological factors.
Because proinflammatory cytokines have been associated with depression in patients without autoimmune diseases, investigators set out to determine if patients with PsA and depression differed from those without depressive symptoms in a variety of clinical and serum variables.
In the course of the study, 150 consecutive patients with PsA were screened for depression, using the Hospital Anxiety and Depression Scale (HADS-D). The research team then compared patients with and without depressive symptoms according to their relative prevalence of risk factors for depression, comorbidities, PsA features, and for serum interleukin (IL)-6, TNF-α, and IL-17A.
The researchers found no difference among patients with and without depression in terms of general risk factors for depression and comorbidities. Of the total number of patients screened, 58 patients (38.7%) showed depressive symptoms; these symptoms were also associated with female sex (p = 0.03) and current smoking (p = 0.05). Patients with depression had more nail psoriasis (p = 0.02) and more significant physical disability (HAQ-DI ≥ 0.5) (p < 0.01), and also were had more moderate or high disease activity according to DAPSA score (p = 0.01).
Patients with depression had higher serum IL-6 (p < 0.01) and comparable serum IL-17A and TNF-α to patients without depression. The best predictor of an HADS-D score at or above 8 was a serum IL-6 level of 2.27 pg/ml.
Using multivariate logistic regression analysis, the investigators confirmed that a serum IL-6 ≥ level of 2.27 pg/ml was independently associated with depression.
“Higher serum Il-6 is associated with depressive symptoms,” the authors wrote. “This association suggests a direct role of systemic inflammation in the modulation of mood in PsA patients.”
—Rebecca Mashaw
Reference:
De Lorenzis E, Gerlando Natalello G, Dario Bruno D, et al. Psoriatic arthritis and depressive symptoms: does systemic inflammation play a role? Clin Rheumatol. 2021;40(5):1893-1902.