Heart disease patients who have anxiety have twice the risk of dying from any cause compared with those who do not have anxiety, according to a study.
Patients with both anxiety and depression have triple the risk of dying, researchers reported in an article published March 19 on the website of the Journal of the American Heart Association.
Many studies have linked depression to an increased risk of death in heart disease patients, said Lana Watkins, PhD, the studys lead author and an associate professor in Psychiatry and Behavioral Sciences at Duke University Medical Center in Durham, N.C. However, anxiety hasnt received as much attention.
Studies show that depression is about three times more common in myocardial infarction patients. The American Heart Association recommends that heart patients be screened for depression and treated if necessary.
Depressed heart disease patients often have anxiety, suggesting anxiety may underlie the risk previously attributed solely to depression, Watkins said. Its now time for anxiety to be considered as important as depression, and for it to be examined carefully.
In the study, 934 heart disease patients, average age 62, completed a questionnaire measuring their level of anxiety and depression immediately before or after a cardiac catheterization procedure at Duke University Medical Center. Patients had anxiety if they scored 8 or higher on a scale composed of seven common characteristics of anxiety, with each item rated from 0 to 3 (range of possible scores: 0-21). Depression was measured using a similar scale composed of seven symptoms of depression.
After accounting for age, heart failure, kidney disease and other factors that affect death risk, the researchers found that 90 of the 934 patients experienced anxiety only, 65 experienced depression only and 99 suffered anxiety and depression.
Among 133 patients who died during three years of follow-up, 55 had anxiety, depression or both. The majority of deaths (93 of 133) were heart-related.
Researchers measured anxiety and depression during cardiac catheterization because levels better reflected how patients normally handle stressful situations.
Anxiety and depression each influence risk of death in unique ways. Anxiety, for example, increases activity of the sympathetic nervous system that controls blood pressure. People who worry a lot are more likely to have difficulty sleeping and to develop high blood pressure, Watkins said.
The link between depression and mortality is more related to behavioral risk factors, she said. Depression results in lack of adherence to medical advice and treatments, along with behaviors like smoking and being sedentary.
Future studies should test strategies to manage anxiety alone and with depression in heart disease patients, Watkins said.
Anxiety-reducing medications combined with stress management could improve outcomes for patients with just anxiety, whereas patients with anxiety and depression may need a stronger intervention involving more frequent outpatient monitoring and incentives to improve adherence, she said.
The full study is available at http://jaha.ahajournals.org/content/2/2/e000068.full.