BackgroundDepression affects 20–30% of individuals with heart failure (HF), and it is associated with worse health outcomes independent of disease severity. One potential explanation is the adverse impact of depression on HF patients’ adherence to the health behaviors needed to self-manage their condition. The aim of this study is to identify characteristics associated with lower adherence in this population, which could help to recognize individuals at higher risk and eventually tailor health behavior interventions to their needs.MethodsUsing data from a randomized, controlled, collaborative care treatment trial in 629 patients with HF and comorbid depression, we performed mixed effects logistic regression analyses to examine the cross-sectional and prospective relationships between medical and psychosocial variables and health behavior adherence, including adherence to medications, a low-sodium diet, and physician appointments.ResultsIn cross-sectional analyses, married marital status and higher physical health-related quality of life (HRQoL) were associated with greater overall adherence (compared to married, single Odds Ratio [OR] = 0.46, 95% Confidence Interval [CI] = 0.26–0.80; other OR = 0.60, CI = 0.38–0.94; p = .012. Physical HRQoL OR = 1.02, CI = 1.00-1.04, p = .047). Prospectively, greater levels of social support were associated with improved overall adherence one year later (OR = 1.04, 95% CI = 1.00-1.08, p = .037). Social support, HF symptom severity, race and ethnicity, and age were predictors of specific types of adherence. Neither depression nor optimism was significantly associated with adherence outcomes.ConclusionsThese results provide important preliminary information about risk factors for poor adherence in patients with both HF and depression, which could, in turn, contribute to the development of interventions to promote adherence in this high-risk population.Trial registrationhttps://clinicaltrials.gov/ct2/show/NCT02044211; registered 1/21/2014.