Abstract 1123: Association Between Depression and Inflammation - Differences by Race: The META-Health Study
Background: Depression is an independent risk factor for incident cardiovascular disease (CVD), and inflammation has been implicated as a possible mechanism. Little is known about whether depression is associated with inflammation in cohorts that include African-Americans (AA), or whether the association differs by race.
Methods: We studied 216 White and 235 AA participants enrolled in the Morehouse-Emory Partnership to Eliminate Cardiovascular Disparities (META-Health) study. Depression was assessed using the Beck Depression Inventory-II (BDI-II). Plasma levels of C-reactive protein (CRP) and interleukin-6 (IL-6) were measured, and were log-transformed for analysis. Wilcoxon rank sum test was used to compare the means between groups, and Spearman correlation was used to examine the association between BDI-II and biomarkers. Linear regression utilizing sequential models was used to adjust for age, education, systolic and diastolic blood pressure, waist circumference, smoking, diabetes, and LDL.
Results: The mean age was 50.6±9.3 years, 62.6% were female, and 55.2% were AA. There was no difference in the total BDI-II score between AA and Whites (7.6±7.3 vs. 7.0±7.0, p=0.5). AA had higher values of CRP (4.7±6.4 vs. 2.6±3.3 mg/L, p<0.0001) and IL-6 (1.6±2.5 vs. 1.1±1.1 pg/mL, p=0.02). CRP was significantly associated with the BDI-II score in Whites (r=0.23, p=0.002), but not in AA (r=0.009, p=0.9). On multivariate analysis in Whites, BDI-II score remained an independent predictor of CRP when adjusted for age, gender, education, and current smoking, with a 3.2% increase in CRP per 1-unit increase in BDI-II score (p=0.003). Adjusting for metabolic factors (blood pressure, waist circumference, diabetes and LDL) attenuated the association in Whites somewhat, to a 2.2% increase in CRP per 1-unit increase in BDI-II score (p=0.06).
Conclusions: There is a link between depression and inflammation in predominantly White populations, which is in part mediated by metabolic factors. However, this relationship may not apply to other ethnic groups. More research is needed in diverse populations to further investigate the links between depression, inflammation, and CVD risk.