Abstract
The impact of caffeine intake on depression remains controversial, and research investigating the effect of caffeine on depression in patients with heart failure (HF) is limited. Depression and HF interact with each other, as depression exacerbates HF symptoms. Therefore, this research evaluated the link between caffeine consumption and depression in HF patients by reviewing clinical evidence and possible effects on patient management. Data were obtained from the National Health and Nutrition Examination Survey 2005 to 2018. Depressive symptoms were measured using the Patient Health Questionnaire-9, while caffeine intake was assessed via two 24-hour recalls. Multivariable logistic regression was used to examine the relationship between caffeine intake and depression. Stratified analyses and interaction testing were conducted to explore potential effect modification. The study included 964 participants with HF, among whom 182 experienced a depression diagnosis. After controlling for confounders, dietary caffeine intake was positively associated with depressive symptoms. For every additional 100 mg of caffeine consumed, the risk for depression increased by 15%. Those in the top quartile of caffeine consumption exhibited an 85% increased likelihood of experiencing depression relative to individuals in the bottom quartile. Stratified analyses indicated that the associations were consistent across different subgroups. These findings suggest that higher caffeine intake may be linked to greater depression risk among HF patients, which has important implications for patient management and treatment strategies.