AHA Calls for Improved Research of Asian American Cardiovascular Health

August 23, 2010—The American Heart Association (AHA) announced that, according to a scientific statement published in Circulation, there are marked differences in heart disease risk and occurrence among Asian American subgroups, but data on these subgroups are limited. Because of this, the AHA is calling for more research on this fastest-growing racial/ethnic group in the United States. The call to action document is available online ahead of print.

Latha Palaniappan, MD, Chair of the AHA's Scientific Advisory on Cardiovascular Disease in Asian Americans, stated, “Available research shows that subgroups of Asian Americans are at increased risk of complications and death from cardiovascular disease; however, Asian Americans are often studied as a group, which masks the differences within this heterogeneous population.”

According to the AHA statement, Asian Americans represent 25% of all foreign-born people in the United States, with a population projected to reach approximately 34 million by 2050. Major federal surveys have only recently started to classify Asian Americans into seven subgroups: Asian Indian, Chinese, Filipino, Korean, Japanese, Vietnamese, and other Asian. The first six subgroups together constitute more than 90% of Asian Americans in the United States.

In preparing the scientific statement, the investigators reviewed published research on Asian Americans and cardiovascular disease, then identified gaps in knowledge and made recommendations. Dr. Palaniappan noted, “We found many disparities among subgroups. If you group all Asian Americans together, you do not detect these differences.”

The statement cites some of the following risk differences between Asian-American subgroups:

• Chinese Americans have lower rates of peripheral arterial disease than other groups.
• Japanese and Chinese Americans have higher rates of stroke but lower rates of coronary heart disease.
• Asian Indians and Filipinos are at greater risk of coronary heart disease compared to the other subgroups.

The statement identifies research showing that risk factors for Asian Americans differ compared to Caucasians. For example, body mass index is considered normal when it is less than 25 kg/m² for Caucasians. However, an index under 23 kg/m² may be more appropriate for Asians. Some studies also show that Asian Americans metabolize drugs, including those used to treat heart disease, differently than Caucasians and other racial/ethnic groups.

“Looking at this more closely gives us opportunities to improve health disparities among Asian Americans,” stated Dr. Palaniappan. “We need changes in data collection.”

Among the suggested changes: instead of grouping Asian/Pacific Islanders together, separate them into the appropriate groups for more accurate disease characterization. Dr. Palaniappan noted that this is already done in the United States Census, but it is not done commonly in hospitals and clinics. Other recommendations for improving the quality and quantity of data include developing standard Asian specific measurement tools for things such as acculturation, which indicates how well a certain population has adapted to the American culture, as well as diet.

“In Mexican American and Spanish populations we often use language as a marker as acculturation. We say: Do you speak English at home? This is not such a great marker in Asian populations because English is often taught in the home countries. In India, for example, English is a national language,” Dr. Palaniappan said. “Giving many Asian Americans the typical American diet questionnaire does not lead to accurate data collection because these questions do not reflect culturally specific foods.”

The committee also recommends that researchers should “oversample” Asian Americans in population-based and clinical trials to ensure that they are well represented.

“We've done an excellent job in researching disparities in other minority groups, but great gaps remain in our knowledge about Asian Americans,” said Dr. Palaniappan. “We are making a call to action for national funding organizations that the study of Asian Americans should be a priority.”