While different Asian groups vary in their risk for heart disease and stroke, all Asian groups are more likely to die early of a stroke than whites.

Until 2003, U.S. mortality surveys lumped all Asian Americans together. Despite the thousands of miles separating India, the Philippines and Korea, and the cultural distinctions of each country, Asian Americans — at least those in the morgue — were considered one ethnic group.

Now that the surveys distinguish between the six largest Asian subgroups in the United States — Chinese, Japanese, Vietnamese, Indians, Filipinos and Koreans — researchers at Stanford Medicine are learning that the different groups face varying risks.

“This information will help us take care of our diverse populations better,” said Latha Palaniappan, MD, a professor of primary care and population health. “We’re unique at Stanford in that we have a higher percentage of Asians than the rest of the country, so distinguishing between different groups is particularly helpful.”

Using mortality data from 2003 to 2012, Palaniappan and her colleagues have been looking at causes of premature death among the subgroups. They calculate the years of potential life lost, a measure of premature death, from various causes. For research published recently in the Journal of the American Heart Association, they looked at deaths from cardiovascular disease.

One finding jumped out: While Asians as a group lived longer (87 years for women and 81 for men) than non-Hispanic whites (81 and 76), Asian Americans in each subgroup were more likely than non-Hispanic whites to die early from a stroke. That held true for both men and women.

Palaniappan said such a finding is an example of why the mining the data is so important: A long average lifespan can hide a propensity for certain diseases.

“Knowing this, we can better screen for stroke,” she said. “We can identify who is at risk, and we can put in preventive measures.”

The research also found that of the subgroups, Asian Indians and Filipinos were most likely to die early from heart attacks, while Filipinos and Vietnamese were the most likely to die early from strokes.

Palaniappan said the differences were likely due to a combination of genetic and cultural factors. She is working on another study to tease out the differences and to look at mixed-race populations. “We want to disentangle these questions of what’s social and what’s biological,” she said.

In addition, the researchers found that over time, as medical treatment has improved, all subgroups were losing fewer years of life to cardiovascular diseases.

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