Association between C-reactive protein and depressive symptoms in women with rheumatoid arthritis

Converging lines of evidence support an association between systemic inflammation and depressive symptoms. Neuroimmune pathways may account for the high prevalence of depression in individuals with inflammatory conditions such as rheumatoid arthritis (RA). However, this relationship is complicated by factors linked to both inflammatory disease activity and mood, such as pain and physical disability. The goal of this cross-sectional study was to examine the relationship between C-reactive protein (CRP) and depressive symptoms among 173 women with RA. Somatic symptoms of depression and circulating CRP were significantly associated in regression analyses adjusted for body mass index (β = .19, p < .05), but this relationship was attenuated when pain and disability were included as covariates (β = .09, p = .24). CRP was not significantly associated with negative mood symptoms of depression. Findings suggest that depression in the context of RA may result from the overlap of somatic depressive and RA symptoms rather than neuroimmune pathways.