In a contemporary cohort of acute heart attack patients, 70 percent of the patients were unaware they had coronary heart disease (CHD) prior to the event and 60 percent of those patients were women or young men. However, these two subgroups are less likely to qualify for aggressive preventive therapy and, therefore, do not receive preventive medications that could reduce the heart attack risk, according to a study being presented at the American Heart Association (AHA) scientific sessions in Orlando, Fla., on Nov. 16.
"For those patients with known coronary disease, the evidence and guidelines are fairly clear about the benefit of aggressive medical therapy, including an aspirin and statin, regardless of your age or gender," says Michael Miedema, MD, a cardiology fellow at the University of Minnesota working in collaboration with researchers at the Minneapolis Heart Institute® at Abbott Northwestern Hospital in Minneapolis. "However, for patients without known coronary disease, the optimal approach is much less clear. We currently only treat high-risk patients but our data show that women and young males, who rarely qualify as high risk, make up a substantial portion of the current heart attack population."
The researchers assessed the Minneapolis Heart Institute's Level One heart attack program to better understand the presence of premature CHD in patients without a prior history of CHD presenting to their facility with ST-elevation myocardial infarction (STEMI), or an acute heart attack.
From March 2003 to January 2010, 3,038 patients were evaluated, and 70.3 percent did not have previously diagnosed CHD prior to their heart attack and 41.7 percent qualified as premature. Despite similar rates of high cholesterol, patients with premature disease (men 55 years or younger, women 65 years or younger) were approximately half as likely to be on a statin prior to their heart attack (10.45 vs. 19.4 percent). Aspirin and combination therapy were being used significantly less often as well.
The Framingham Risk Score is the most commonly used risk calculator, using the patient's age, gender and risk factors such as cholesterol and blood pressure to determine the potential risk for a cardiac event. However, Miedema suggests that the Framingham Risk Score is heavily weighted toward age and gender.
"If you're an older male, you're much more likely to qualify for preventive therapy while females and younger males often do not meet criteria despite similar risk factors," Miedema says. "While older males are still the most likely group to have heart attacks, we have shown that women and patients with premature disease make up a substantial portion of the heart attacks we are seeing and very few of these patients are on the medications which research has shown to prevent heart attacks. Better methods of risk assessment could potentially allow us to target more people truly at high risk for an event and avoid excessive treatment of those who are low risk."
Based on the study findings, the study authors concluded without improved preventive care strategies, the possibility of further decreasing the rate of STEMIs in the United States may be "challenging."