Effects of Mood and Anxiety Disorders: Future Directions for Research

Usually underdiagnosed and undertreated, major depression and anxiety disorders are encountered commonly in patients with CAD and patients referred for evaluation of chest pain. However, a burgeoning literature on the importance of major depression and anxiety disorders in patients with heart disease has accumulated over the past two decades. Several studies have shown depression and its associated symptoms to be a major risk factor in both the development of CVD and death after an index MI.

Further evidence is accumulating regarding the increased risk of patients with anxiety disorders or anxiety symptoms for the development of IHD, although currently there is a dearth of information about the prevalence of anxiety disorders in patients with CAD or CHF. An intriguing area of investigation involves the possible effects of anxiety disorders on the thrombovascular system and the "reciprocal" cardiovascular contributions to anxiety symptoms or anxiety syndromes, such as panic disorder. Although treatment of depression in many patients with CVD improves their dysphoria and other signs and symptoms of depression, are these agents safe and effective in the treatment of anxiety disorders as well? One of many important questions to be answered is whether aggressive and consistent treatment of anxiety and depressive syndromes in patients with CVD not only improves their quality of life but diminishes cardiovascular-related morbidity and improves survival.

Which treatment modalities (psychotherapeutic versus psychopharmacologic or a combination) will be most effective in patients with recurrent or more severe depression remains to be determined. Treatment studies also may assess the relation between depression and subsequent compliance with medication and modification of risk factors for CVD. Future studies undoubtedly should continue to scrutinize whether there are gender-specific psychiatric and psychobiological differences in susceptibility to CVD, symptom presentation, vulnerability to adverse outcomes after treatment for CVD (e.g., CABG), and response to depression treatment. Although women are more vulnerable to depression and CVD is the leading cause of death among adult women in the United States, the question of whether the impact of depression and anxiety on CVD differs by gender has been understudied, with the results to date conflicting.

The associations between diseases of the CNS (anxiety and depressive disorders) and disorders of peripheral "end organs" such as the heart raise intriguing questions regarding what is "cardiovascular" or "psychiatric." Molecular biological techniques may provide further opportunity for the elucidation of the relation between cardiovascular and psychiatric diseases, given the possibility that clinically distinct disorders, such as depression and IHD, may share several genetic susceptibility loci. Illumination of the interplay between anxiety disorders, depressive syndromes, and the thrombovascular system, particularly in patients with CVD, undoubtedly will lead to the development of new treatment modalities that not only will improve patients' quality of life but potentially will decrease their morbidity and improve long-term survival rates.