Affective traits and adiposity : a prospective, bidirectional analysis of the African American Health study data

Abstract

Research indicates that negative affective traits (e.g., depression) are predictors and consequences of excess adiposity. Given that racial minorities and positive affective traits have been underrepresented in past investigations, more prospective studies are needed which examine multiple affective traits in relation to obesity in these populations. The objective of the current study was to investigate the prospective, bidirectional associations between multiple affective traits and multiple adiposity indicators in African Americans using data from the African American Health (AAH) study. The AAH study is a prospective cohort study of African Americans aged 49-65 years at baseline (N = 998). The longest follow-up period in the current study was 9 years (N = 579). Self-reported and measured body mass index (BMI; kg/m2) and body fat percent (BF%) were used as adiposity indicators. Depressive symptoms were assessed with the 11-item Center for Epidemiologic Studies-Depression Scale (CES-D), and anxiety was assessed using the Generalized Anxiety Disorder-2 (GAD-2) scale. Positive affective traits were assessed with the Vitality subscale of the Short Form-36 and Positive Affect subscale from the CES-D. Latent variable path analysis, a structural equation modeling technique, was conducted. Although fit statistics indicated that the models fit the data (RMSEA < .06), examination of the structural paths revealed that the CES-D and GAD-2 were not predictors or consequences of self-reported BMI, measured BMI, or BF% (ps > .05). Likewise, Vitality and CES-D Positive Affect were not related to any adiposity indicator (ps > .05). The results of this prospective cohort study suggest that affective traits are not predictors or consequences of adiposity in middle-aged African Americans and that this group may require obesity prevention or intervention programs with little to no emphasis on affective traits. Possible explanations for the current results include ethnic differences in the mechanistic pathways between affective traits and adiposity.