Depression, Anxiety Predict Events in Patients With Stable CAD

Susan Jeffrey
January 10, 2008 — A new study confirms that patients with stable coronary artery disease (CAD) and a diagnosis of depression or anxiety have a greater risk for cardiac events.
Patients with concomitant diagnoses of stable CAD and either major depressive disorder (MDD) or generalized anxiety disorder (GAD) had a greater than 2-fold increase in the risk for major adverse cardiac events (MACEs) in the 2 years after a baseline assessment, although comorbid MDD and GAD seemed not to be additive in their effects on cardiac risk.
The report appears in the January issue of the Archives of General Psychiatry. Study authors are Nancy Frasure-Smith, PhD, from McGill University, Montreal Heart Institute Research Center, Centre Hospitalier de l'Université de Montréal Research Center and the University of Montreal; and François Lespérance, MD, from Montreal Heart Institute Research Center, Centre Hospitalier de l'Université de Montréal Research Center and the University of Montreal.
Increased Atherosclerotic Burden?
Both anxiety and depression have been associated with mechanisms that promote atherosclerosis, but most of the work to date has focused on depression only, largely ignoring the potential impact of anxiety or of the combination of these conditions on the risk for CAD events, the study authors write.
The work that has shown apparent links between anxiety and prognosis in patients with cardiac disease has largely explained this association by other factors such as disease severity, Dr. Frasure-Smith told Medscape Psychiatry. However, both GAD and MDD have many overlapping symptoms and some genetic links, and antidepressants can be used to treat both conditions, leaving open the question of a prognostic association between anxiety and cardiac prognosis.
The aims of the present analysis from the Epidemiological Study of Acute Coronary Syndromes and the Pathophysiology of Emotions were to examine the relationship between the diagnoses of MDD and GAD, based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) in patients with stable CAD, as well as self-reported symptoms of anxiety and depression assessed approximately 2 months after hospital discharge for acute coronary syndromes, on the risk for subsequent cardiac events during 2 years.
The researchers also looked at whether the combination of anxiety and depression might further increase the 2-year risk for MACEs vs that seen with either condition alone.
Included in the study were 804 patients with stable CAD, 649 of whom were men. All were assessed at 2 months after hospital discharge with the Beck Depression Inventory II (BDI-II), the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A), and the Structured Clinical Interview for DSM-IV, masked to the self-reports of symptoms.
Patients were then followed up at 2 years for the occurrence of MACEs, including cardiac death, myocardial infarction, cardiac arrest, or nonelective revascularization.
The study authors report that the prevalence of depression, although not as high as in patients hospitalized with CAD, was higher vs the general community of people with stable cardiac disease. The prevalence of GAD was almost as high, and the prevalence of both conditions was higher vs the general population, said Dr. Frasure-Smith.
Of the 804 patients, 57 (7.1%) met the criteria for MDD and 43 (5.3%) for GAD. There were 11 (1.4%) patients who had comorbidity of both conditions. A total of 220 (27.4%) patients had elevated depressive symptoms with BDI-II scores of 14 or higher, and 333 (41.4%) had elevated HADS-A scores of 8 or greater, with overlap occurring in 21.1%.
Both GAD and MDD predicted the occurrence of major cardiac events during the 2-year period; both conditions were associated with approximately a doubling of risk, even after adjustment for multiple background and cardiac disease severity measures.
"Although before covariate adjustment there was evidence of increased risk with elevated self-report symptoms, even in the absence of meeting DSM-IV criteria, after covariate control only the increased risks associated with MDD and GAD remained significant," the study authors write.
However, patients with comorbid MDD and GAD or elevated symptoms of both anxiety and depression on self-report were not at greater risk for subsequent MACEs than those with only 1 of these conditions.
"We know that generalized anxiety disorder is difficult to treat, and really affects people's quality of life and their ability to function," Dr. Frasure-Smith said. "But up until now, we didn't know that any psychiatric condition besides major depression and possibly panic disorder might also have cardiac prognostic implications.
"This suggests that when you see someone with comorbid GAD and cardiac disease, comorbid MDD and cardiac disease, special attention needs to be paid to them, both from the point of view of their psychiatric condition, but also in controlling their other risk factors," she concluded. "We don't have evidence that psychiatric treatment for either of these conditions will affect cardiac outcome, but we do know that cardiac risk factor control affects cardiac outcomes, so these are patients at high risk who should be receiving the best evidence-based cardiac medications and treatment that we can provide."
Dr. Frasure-Smith has received grant support from IsodisNatura and GlaxoSmithKline and honoraria from Solvay and Tromsdorff. Drs. Frasure-Smith and Lespérance have received placebo and active medication from Lundbeck Canada for an investigator-initiated, peer-reviewed funded trial. The disclosure for Dr. Lespérance appears in the article. The study was supported by the Medical Research Council of Canada, an unrestricted grant from GlaxoSmithKline, the Charles A. Dana Foundation, the Foundation of the Montreal Heart Institute, the Pierre David Fund, and the Fondation du Centre Hospitalier de l'Université de Montréal.
Arch Gen Psychiatry. 2008;65:62-71.