Many patients with CHD have poor knowledge of MI symptoms

Most do not perceive themselves at elevated cardiovascular risk.

Issue: July 2008

Nearly half of patients with a history of heart disease have poor knowledge about the symptoms of a myocardial infarction and do not perceive themselves to have an elevated cardiovascular risk, according to a report published in the Archives of Internal Medicine.

More than 3,500 patients with a history of MI or invasive procedure for ischemic heart disease were asked to identify his/her level of perceived risk for a future MI by responding to true/false questions.

The average cardiac knowledge score was 71%. Despite history of coronary heart disease, 46% of patients had scores lower than 70%.

“Patients with CHD continue to have numerous misconceptions about the disease and their risk for future events,” Kathleen Dracup, RN, DSNc, professor and dean, University of California, San Francisco, School of Nursing, told Cardiology Today.

“People who already had a MI or heart surgery were not more knowledgeable about the nature of cardiac symptoms than those who did not have this history. Our results help explain an often described finding that patients who have had a previous MI do not delay less than patients who have not had a MI in the past,” she said.

Lack of knowledge established

Higher cardiac knowledge scores were associated with women, younger individuals, those with higher education and those who had previously participated in cardiac rehabilitation or received care by a cardiologist rather than internist or general practitioner.

The other groups are “more likely to require special efforts during medical office visits to review symptoms of MI and learn the appropriate actions,” the researchers wrote.

When patients were asked about their perceived probability of having a MI within the next five years, 57% perceived themselves as being at higher risk compared with their healthy peers. Patients who previously underwent coronary artery bypass surgery felt significantly less vulnerable for a future MI. Although men had an overall lower mean cardiac knowledge score, they were more confident they would recognize symptoms compared with women (47% vs. 36%), according to Dracup.

“Knowledge and confidence are not always related,” she said in the interview. “It is difficult to speak with patients about their risk for future cardiac events — everyone wants to normalize.”

“These findings should help fuel the recent focus on the barriers, benefits and methods to improve participation in cardiac rehabilitation by coronary artery disease patients,” Robert A. Phillips, MD, PhD, wrote in an accompanying editorial. – by Katie Kalvaitis

For more information:

Dracup K, McKinley S, Doering LV, et al. Acute coronary syndrome. What do patients know? Arch Intern Med. 2008;168:1049-1054.
Phillips RA. Another boost for cardiac rehabilitation. Arch Intern Med. 2008;168:1029.

The study provides an important window into an issue that has long troubled me. Why do Americans in general have such low insight into the functioning of their bodies and the nature of disease? The current study lays to rest the excuse that deficient knowledge is based on lack of concern, since all the participants in this study knew they had coronary disease but were still unaware of much of what they should have known. Can we attribute it to a deficient education system during which school children should be taught about biology, health and body functions? The authors did not compare American responses with those of Australia and New Zealand, which comprised nearly half of the population. Can we blame the educational system in all their countries? Or is the problem a more fundamental deficiency in man’s willingness to understand scientific principles and prudent behavior?

– Jay N. Cohn, MD
Professor of Medicine, University of Minnesota Medical School, Minneapolis, Minn.