Shorter people at higher risk of heart disease

A shorter height is directly associated with increased risk of coronary heart disease, a new large-scale study led by an Indian-origin scientist has found.

The study by the University of Leicester found that every 2.5 inches change in height affected the risk of coronary heart disease by 13.5 per cent.

For example, compared to a 5ft 6inch tall person, a 5 foot tall person on average has a 32 per cent higher risk of coronary heart disease because of their relatively shorter stature.

"For more than 60 years it has been known that there is an inverse relationship between height and risk of coronary heart disease," said Professor Sir Nilesh Samani, British Heart Foundation Professor of Cardiology at the University of Leicester, who led the research.

"It is not clear whether this relationship is due to confounding factors such as poor socioeconomic environment, or nutrition, during childhood that on the one hand determine achieved height and on the other the risk of coronary heart disease, or whether it represents a primary relationship between shorter height and more coronary heart disease," he said.

Using a genetic approach, researchers have shown that the association between shorter height and higher risk of coronary heart disease is a primary relationship and is not due to confounding factors.

"Height has a strong genetic determination and in the last few years a large number of genetic variants have been identified in our DNA that determines one's height," said Samani.

"The beauty about DNA is that it cannot be modified by one's lifestyle or socio-economic conditions. Therefore if shorter height is directly connected with increased risk of coronary heart disease one would expect that these variants would also be associated with coronary heart disease and this is precisely what we found," he said.

The researchers analysed genetic data on almost 200,000 persons with or without coronary heart disease. They examined whether 180 genetic variants that affect height are also associated with coronary heart disease.

They found that for every change in height of 6.5 cm (approx. 2.5 inches) caused by these variants the risk of coronary heart disease changed on average by 13.5 per cent.

"The more height increasing genetic variants that you carry the lower your risk of coronary heart disease and conversely if you were genetically shorter the higher your risk," said Dr Christopher Nelson, British Heart Foundation-funded lecturer who undertook the analysis.The study is published in the New England Journal of Medicine.