We appreciate the interest of Ziegelstein et al in our article.1 We agree with Ziegelstein et al that psychological factors, such as depression, may be important mediators of the relationship between medication nonadherence and adverse outcomes. Defining the mechanism between medication nonadherence and adverse outcomes in coronary heart disease was not an aim of our critical review. While some results of our review suggest that adherence to medical regimens confers a protective effect on survival, further study is necessary to define the mechanism by which adherence affects outcomes and to identify interventions that successfully increase adherence among patients at risk for coronary heart disease. Based on the data presented by Ziegelstein et al, future studies should consider depression as a potential mediator of the relationship between nonadherence and cardiovascular events.
McDermott MM, Schmitt B. Depression, Adherence Behavior, and Coronary Disease Outcomes. Arch Intern Med. 1998;158(7):808-809. doi: