Are You Too Smart to Have a Heart Attack?

Feb. 10, 2010— -- How well a person does on a standardized intelligence test -- in other words, their IQ score -- may be related to his or her risk for having a heart attack, according to a team of researchers who have been investigating the potential link between the brain and the heart.

In a study of more than 1,100 middle-aged Scottish men and women who were followed for 20 years, a low score on an IQ test was a better predictor of death from heart disease than traditional risk factors such as systolic blood pressure -- the first number in a blood pressure reading -- income, and lack of exercise. Only smoking topped low IQ as a predictor of death, according to G. David Batty, a researcher at the University of Glasgow.

Batty and his colleagues, who reported their observations in the European Journal of Cardiovascular Prevention and Rehabilitation, found a similar link when they studied Vietnam veterans.

The brain-heart link, they wrote, might reflect skills associated with intelligence, such as the ability to understand and act on advice about healthy lifestyles, Batty wrote.

However, these conclusions drew sharp criticism from leading American cardiologists.

IQ should not be factored into the equation for identifying high-risk patients or in initiating aggressive prevention strategies, cautioned Dr. Elizabeth Barrett-Connor of the University of California San Diego, who called the study a misleading grab for headlines.

The relationship with mortality is inescapably confounded, added Dr. Merle Myerson, director of Preventive Cardiology at St. Luke's-Roosevelt Hospital in New York.

"What goes along with lower IQ is generally lower socioeconomic status, lower access to medical care, lower awareness of risk factors -- diagnosis and treatment -- et cetera," she told ABC News and MedPage Today.

Dr. Steve Nissen, chair of Cardiovascular Medicine at the Cleveland Clinic, criticized the failure to adjust for these important factors that, for economic reasons, are more likely to accompany low IQ.