Ethnic differences in need for heart pacemakers may have genetic link
Researchers have found evidence to show that South Asian people (from India, Pakistan, Bangladesh and Sri Lanka) are less likely to require a pacemaker for an abnormally low heart rate compared to white people of European origin.
Abnormally slow heart rate (bradycardia) occurs when the electrical conduction system of the heart does not work properly. Symptoms include dizziness, fainting, confusion, shortness of breath and tiring easily after light physical activity.
The researchers looked at the number of permanent pacemakers implanted in Leicestershire over an 8 year period. During that time, 4,883 people had a permanent pacemaker implanted, which represents about five people in every 1000 of the local population. However, the rate of permanent pacemakers fitted in white people was nearly six times higher than in South Asian people, even when factors such as risk of heart disease and age were taken into account.
“From previous research comparing the two populations, we know that South Asians have higher incidences of coronary artery disease and stroke compared to people of European origin," says Iain Squire, professor of cardiovascular medicine. "However, with this particular heart condition, our study shows that the level of susceptibility is in fact reversed."
Professor Sir Nilesh Samani, cardiovascular theme lead for the NIHR Leicester BRC, said: “Leicester is a particularly good place to undertake research of this kind because of our mixed population. The results of this study raise the possibility that genetic differences at least partly explain the differences in risk of different heart conditions between South Asians and Europeans. Finding out the mechanisms, including any genetic variation that underpins these differences, is certainly warranted by further research.”
The National Institute for Health Research (NIHR) Leicester Biomedical Research Centre (BRC) is a partnership between University Hospitals of Leicester NHS Trust, the University of Leicester and Loughborough University.