Less heart disease, stroke in immigrants than in US-born

WASHINGTON: People living in the U.S. but born elsewhere may have lower risk for heart disease and stroke than their native-born neighbors, suggests a new study.

Foreign-born residents had a range of risks, however. Women from Europe and men from Africa or South America had the lowest stroke rates compared to U.S.-born peers. Heart disease rates were lowest among men and women from Asia, the Caribbean, Central America and Mexico and highest among men from the Indian Subcontinent and Europe.

Heart disease is the top cause of death in the U.S., and stroke is the fifth-leading cause, the study team points out in the Journal of the American Heart Association.

Past research has suggested that U.S. residents born elsewhere are less likely to die of heart disease than those born in the U.S., and less likely to have heart disease risk factors like obesity, diabetes and high blood pressure, the authors note.

The foreign-born population of the U.S. has swelled from less than 10 million in 1970, or about 5 percent of the population, to 40 million, or 13 percent, in 2010, write the authors, led by Dr. Jing Fang of the Centers for Disease Control and Prevention in Atlanta.

To assess current differences in heart disease prevalence, the researchers analyzed data on 258,862 adults who participated in the National Health Interview Survey between 2006 and 2014. Overall, 16.4 percent were born outside the U.S., and researchers further divided these individuals into six groups based on their region of origin: Africa; Asia; Central America and the Caribbean; Europe; Indian Subcontinent; Mexico and South America.

Among U.S.-born men, 8.2 percent had coronary heart disease and 2.7 percent had experienced a stroke, compared with 5.5 percent and 2.1 percent, respectively, of foreign-born men. Among native-born women, 4.8 percent had heart disease compared with 4.2 percent of foreign-born women, and 2.7 percent reported having had a stroke compared with 1.9 percent of foreign-born women.

Overall, heart disease risk was lowest among individuals from Africa, at 3.1 percent, while South American-born adults had the lowest risk of stroke, at 1.1 percent.

Women born in Africa had the lowest heart disease rates of any group, at 1.6 percent, but they also had the highest stroke rates among all women at 2.9 percent.

Men from Africa had the lowest heart disease and stroke rates among all men, at 4.4 percent and 0.8 percent, respectively, compared with 8.2 percent and 2.7 percent among U.S. men.

After the investigators accounted for education and other factors, they found that the duration of a person’s residence in the U.S. did not affect their likelihood of having heart disease or a stroke.

The data is self-reported, Dr. Fang noted in a telephone interview, so study participants had not necessarily received a formal diagnosis of heart disease or stroke. Also, she said, because of the small number of immigrants from certain countries, it wasn’t possible to analyze the results on a country-by-country level.

Among the study’s other limitations, said Dr. Yvonne Commodore-Mensah, who wasn’t involved in the research, only about 45 percent of the participants from Mexico, Central America and Caribbean had health insurance, compared to about 86 percent of the U.S.-born adults, which could help explain their lower reported rates of heart disease and stroke.

The study also didn’t capture people with heart disease or stroke who go home to their country of origin to seek less expensive health care, said Commodore-Mensah, who studies cardiovascular health in immigrants at Johns Hopkins School of Nursing in Baltimore.

“Heart disease may be a process that takes years and may be undiagnosed, so I’m concerned that a high percentage of these foreign-born individuals may have undiagnosed conditions,” she said in a phone interview.

Future studies should aim to look at immigrants’ country of origin, rather than the general region, she added. “It’s not a homogenous group. There may be some populations that are at higher risk than others. When we aggregate data, we lose a lot of information that may actually help us to create culturally appropriate public health interventions.”