2008/02/01 by Jesse C. Stewart, Denise Janicki-Deverts, Denise Janicki‐Deverts +2 · 2 citations
Medicine · Neuroscience · #Cardiac Health and Mental Health #Tryptophan and brain disorders #Stress Responses and Cortisol
paper · doi:10.1097/psy.0b013e3181642a0b
Objective: Recent evidence suggests that depressive symptoms and hostility may act together, as interacting factors, to have an effect on the circulating levels of inflammatory markers relevant to coronary artery disease. Further research, however, is needed to clarify the nature of this interaction and to determine whether previous findings extend to older adults. In this report we examined the cross-sectional associations of depressive symptoms, hostility, and their interaction with circulating levels of two such inflammatory markers—interleukin-6 (IL-6) and C-reactive protein (CRP). Methods: A total of 316 healthy, older adults underwent a blood draw for the assessment of serum IL-6 and CRP and completed the Beck Depression Inventory-II and the Cook-Medley Hostility Scale. Regression analyses were performed to examine depressive symptoms, hostility, and their interaction as predictors of serum IL-6 and CRP. Results: After adjustment for demographic factors, cardiovascular risk factors, and health behaviors, we detected depressive symptoms × hostility interactions for serum IL-6 (ΔR2 = .027, p < .01) and CRP (ΔR2 = .015, p < .05). Simple slope analyses revealed that hostility was positively related to serum IL-6 only among individuals with higher depressive symptoms. The pattern of results was similar for serum CRP, although none of the simple slopes was significant. Conclusions: Our findings suggest that depressive symptoms may moderate the hostility-inflammation relationship such that hostility may augment inflammatory processes relevant to coronary artery disease only in the presence of depressive symptoms. Our results also extend previous findings from younger adults to older adults from the general community. IL-6 = interleukin-6; CRP = C-reactive protein; CAD = coronary artery disease; BDI = Beck Depression Inventory; Ho Scale = Cook-Medley Hostility Scale; TNF-α = tumor necrosis factor-α; PHHP = Pittsburgh Healthy Heart Project; SBP = systolic blood pressure; DBP = diastolic blood pressure; MAP = mean arterial pressure; BMI = body mass index; HDL = high-density lipoprotein; LDL = low-density lipoprotein.