Elisabeth J. Martens of Tilburg University in the Netherlands and colleagues assessed 1,015 outpatients with stable coronary heart disease. After average follow-up time of about 6 years, 371 cardiovascular events occurred.
The study, published in the Archives of General Psychiatry, found that after adjusting for age, the annual rate of cardiovascular events -- stroke, heart attack, heart failure and death -- was 9.6 percent in the 106 participants with general anxiety disorder and 6.6 percent in the 909 participants without an anxiety disorder.
After adjusting for potentially confounding variables such as sex, co-occurring conditions, heart disease severity and medications -- generalized anxiety disorder was associated with a 74 percent increased risk of cardiovascular events.
"This leaves the question of why generalized anxiety disorder is associated with adverse outcomes in patients with coronary heart disease," the study authors said in a statement.
Anxiety may be linked with surges in catecholamines -- "fight or flight" hormones -- that may be related to heart risk, the authors suggested.