By AMERICAN HEART ASSOCIATION NEWS

South Asians living in the U.S. are more likely to die from heart disease than the general population. But this risk has been largely hidden by a lack of data, researchers say.

Immigrants coming from Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan and Sri Lanka are one of the fastest growing populations in the U.S.

“We’ve realized that South Asians are dying of heart disease a lot earlier than other ethnic groups, and that it’s devastating to their community,” said cardiologist Dr. Annabelle Volgman, who led an expert group that on Thursday published a report on the issue for the American Heart Association in the journal Circulation.

There were around 3.4 million people of South Asian descent living in the U.S. as of 2010, according to the U.S. Census Bureau. But despite their numbers, the threats to South Asians’ cardiovascular health have been obscured because researchers have been looking at Asian-Americans as a monolithic group. But when examined individually, South Asians have a higher risk of heart disease than other Asian groups, especially East Asians from China, Japan and Korea.

“We need to look at the different Asian groups within the Asian community so that we’re not all lumped together,” said Volgman, whose family is originally from the Philippines. “We’re not alike in terms of cardiovascular risk factors.”

It is not clear why South Asians are more prone to heart disease than other groups. While it is clear that cardiovascular disease can be passed down in families, researchers have yet to find a specific genetic cause that would make South Asians more at risk than other groups.

“We’ve observed the increased risk, but we are still looking for the smoking gun,” said Dr. Latha Palaniappan, an internist and clinical researcher who focuses on the gap in medical knowledge about Asian subgroups. She co-chaired the new report with Volgman.

Although the genetics are not yet clear, there are some conditions that increase the risk of cardiovascular disease among South Asians. One key connection is an increased risk of diabetes at a young age, and another is cholesterol abnormalities. Because studies indicate that South Asians develop heart disease earlier in life than other groups, doctors are working to increase awareness among the South Asian community to get tested for signs of cardiovascular problems as early as possible.

“I think that accessing preventative health care has been less than optimal in South Asian populations because they aren’t aware that they’re at increased risk,” Palaniappan said.

Although cardiovascular disease can be inherited, researchers say much of the risk can be mitigated by lifestyle changes, such as diet, exercise and avoiding tobacco. Exercise is especially important, as studies show that South Asians exercise less than other groups, and are also less aware of the connection between lack of exercise and heart disease. Diet is also a key part of heart health, and although many South Asians are vegetarian, their diets include too much fat, sugar and refined carbohydrates, and these tendencies increase the longer they have lived in the U.S.

In the past, researchers saw a significant difference between South Asians living in their countries of origin, who were more active and ate healthier diets than migrant groups. But now poor lifestyle habits from the U.S. are making their way back to Asia.

“The same increased risk that we were observing in worldwide diaspora (scattered) populations we’re now seeing in India because India is becoming more Westernized in terms of a more sedentary lifestyle and less healthy food choices,” Palaniappan said.

But researchers believe that these trends can be reversed with increased awareness. Now that they’re focused on the increased risk of heart disease in South Asians, researchers can target studies specifically to this group and physicians can work with their patients to address heart health at an earlier age.

“Because South Asians tend to have cardiovascular events at a younger age we really want to emphasize the need for more studies so that we don’t lose young mothers and fathers,” Volgman said.

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