London, July 15: People who have a lower than average IQ are at a greater risk of developing heart disease, according to researchers.
A new study of more than 4,000 people, published in the ‘European Heart Journal’, has found that IQ explained more than 20 per cent of the difference in mortality between high and low socio-economic groups.
And, this applied even when known heart disease risk factors were considered.
Dr David Batty of University of Glasgow, who led the study, said: “We already know that socio-economically disadvantaged people have worse health and tend to die earlier from conditions such as heart disease, cancer and accidents.
“Environmental exposures and health-related behaviours, such as smoking, diet and physical activity, can explain some of this difference, but not all of it.”
According to the researchers, this raises the possibility that as yet unmeasured psychological factors need to be considered and that one of these is intelligence or cognitive function, commonly referred to as IQ.
As expected from past trends, the study revealed that those on low incomes and with less education had a higher risk of dying from cardiovascular disease.
But when the researchers took into account IQ and controlled for nine other known heart disease risk factors, IQ alone explained 23% of the differences in mortality between the highest and lowest socio-economic groups in the study.
They offer several possible explanations for this — low IQ scores might simply be a marker of underlying poor health or intelligence might lead to greater knowledge about how to keep healthy, the ‘BBC News’ reported.
Dr Batty said, whatever the explanation, the findings imply the IQ of the public should be considered more carefully when preparing health promotion campaigns.
“Public health messages on things like diet, exercise and smoking could be simplified. For instance, we often read about how some types of alcohol are good for you while others, or even the same ones, are not. The messages can be difficult to interpret, even by knowledgeable people.”
–Agencies