Women referred to stress testing have higher rates of psychiatric disorders than men

Women with anxiety and no history of coronary artery disease had an elevated risk of ischemia compared with women who did not have anxiety and no history of coronary artery disease, according to an analysis of adults who underwent diagnostic myocardial perfusion exercise stress testing.

The ischemia rates were similar among women who had a history of coronary artery disease as well as men in both groups. Women who presented for stress testing had a higher prevalence of psychiatric disorders compared with men.

Lead researcher Nicola J. Paine, PhD, of Concordia University in Montreal, and colleagues published their results online in Circulation: Cardiovascular Quality and Outcomes on Feb. 23.

Previous research found that 17 percent of women and 12 percent of men died within three years of having their first MI, while the hospital mortality rates following an acute MI were 16 percent in women and 11 percent in men.

In this study, the researchers examined 2,342 adults who presented between September 1998 and June 2002 to the Nuclear Medicine department at the Montreal Heart Institute and were referred for exercise stress SPECT.

Patients were excluded if they had a medical condition that had a greater risk of illness morbidity than coronary artery disease, if they were inpatients when they underwent the stress test, if they had MI, PCI or CABG in the four weeks before the stress test, or if they had unstable angina or were unable to exercise before the stress test. They were allowed to continue on their medication regimen.

The researchers used the PRIME-MD (Primary Care Evaluation of Mental Disorders) screening instrument to evaluate the prevalence of mood and anxiety disorders. The PRIME-MD evaluates mood, anxiety, somatoform, alcohol and eating.

They assessed ischemia using SPECT-based myocardial ischemia and a two-day rest-stress protocol. They defined an ischemia response as a two-point change in the stress-rest differential score that was verified by a physician.

Of the participants in this study, 32.5 percent were female. Men had a greater prevalence of hyperlipidemia, diabetes, previous MI, history of coronary artery disease, previous bypass surgery and smokers. At baseline, men had higher diastolic blood pressure readings, while women had higher heart rates. There was no difference in systolic blood pressure.

Women had an elevated risk of presenting with any psychiatric disorder (odds ratio [OR]=1.76), any anxiety disorder (OR=1.78), any mood disorder (OR=1.62) and any comorbid anxiety and mood disorder (OR=1.85). Meanwhile, men had an elevated risk of the presence of ischemia during stress testing (OR=3.63).

The researchers cited a few limitations of the study, including that the results may not be generalizable to general or community hospitals because the Montreal Heart Institute is a specialized cardiology hospital. The findings may also be limited to adults that present with symptoms warranting a stress test. The researchers added that they could not confirm the reason for stress testing and did not have follow-up data on sex differences in treatment as a consequence of psychiatric disorders or ischemia status following the exercise test.

They added that anxiety symptoms or psychophysiological mechanisms may mask coronary artery disease symptoms among women but not men and contribute to referral and diagnostic delays among women.

“Future studies are needed to confirm these hypotheses,” they wrote. “Future work should also investigate the extent to which psychiatric disorders affect care trajectory and/or [coronary artery disease] outcomes among men and women, and whether interventions to improve psychiatric status among those with or at risk for [coronary artery disease] could improve outcomes.”