South Asians in US top heart disease risk
South Asian immigrants in America have a higher risk of heart disease than any other segment of the American population, reports Arun Kumar .india Updated: Feb 04, 2007 03:52 IST
South Asian immigrants in America have a higher risk of heart disease than any other segment of the American population, according to a new study led by an Indian American doctor.
This latest warning comes close after a 52-nation study of 26,000 people has proven that unhealthy lifestyles, make Indians and South Asians prone to a first heart attack as early as 53 years, compared to 59 years in other nations.
The trouble, Medical College of Georgia (MCG) researchers suspect, is that their high-density lipoprotein (HDL), or so-called good cholesterol, doesn't protect many of them like it should and their new lifestyle worsens the risk.
"Research shows that while only nine per cent of whites develop coronary artery disease, while 18 and 25 per cent of South Asian immigrants eventually develop it," said Dr Sunita Dodani, MCG epidemiologist and cardiologist. "Interestingly, South Asians who live in their homelands have normal rates of the disease."
"The dysfunctional HDL and external risk factors like stress from moving and new jobs and high-fat diets make for a deadly combination."
Dr Dodani, a South Asian immigrant herself, and collaborators at MCG and the University of California at Los Angeles studied blood samples of 29 Augusta immigrants, looking for a connection between the gene mutation and dysfunctional HDL.
Dr Dodani and her colleagues suspected that if a subject had thickening of the carotid arteries, he or she would also have dysfunctional HDL and a polymorphism of the Apo-A1 gene.
Interestingly, 40 per cent of them had arterial thickness and, among that group, 17 per cent had high blood pressure and more than 30 per cent had high cholesterol.
Half the study population also had dysfunctional HDL. DNA analysis of those blood samples also found six different mutations of Apo-A1.
“These findings support our theory that the disease, in South Asians, is most likely caused by a combination of things — a dysfunctional HDL caused by a genetic polymorphism.”
The next step, Dr Dodani says, is expanding the study to include more people.
Dr Dodani has applied for funding from the National Institutes of Health to eventually include other populations for a comparative study.
“If the cause is a combination of this gene mutation and other factors, are there preventive strategies that we can employ? Should cholesterol-lowering drugs be started earlier in certain populations? Those are questions we hope to eventually answer.”