Mediators of the impact of a home-based intervention (Beat the Blues) on depressive symptoms among older African Americans

Older African Americans (N = 208) with depressive symptoms were randomly assigned to a home-based nonpharmacologic intervention (Beat the Blues, or BTB) or wait-list control group. BTB was delivered by licensed social workers and involved up to 10 home visits focused on care management, referral and linkage, depression knowledge and efficacy in symptom recognition, instruction in stress reduction techniques, and behavioral activation through identification of personal goals and action plans for achieving them. Structured interviews by assessors masked to study assignment were used to assess changes in depressive symptoms (main trial endpoint), behavioral activation, depression knowledge, formal care service utilization, and anxiety (mediators) at baseline and 4 months. At 4 months, the intervention had a positive effect on depressive symptoms and all mediators except formal care service utilization. Structural equation models indicated that increased activation, enhanced depression knowledge, and decreased anxiety each independently mediated a significant proportion of the intervention's impact on depressive symptoms as assessed with 2 different measures (PHQ-9 and CES-D). These 3 factors also jointly explained over 60% of the intervention's total effect on both indicators of depressive symptoms. Our findings suggest that most of the impact of BTB on depressive symptoms is driven by enhancing activation or becoming active, reducing anxiety, and improving depression knowledge/ efficacy. The intervention components appear to work in concert and may be mutually necessary for maximal benefits from treatment to occur. Implications for designing tailored interventions to address depressive symptoms among older African Americans are discussed.