Chinese immigrants who move in childhood have more cardiovascular risk factors

Chinese immigrants have more cardiovascular risk factors the younger they move and longer they stay, according to research published today in the European Journal of Preventive Cardiology.

"Cardiovascular disease is a major health issue among all immigrant groups in western countries," said lead author Kai Jin, PhD student, University of Sydney, Australia. "But little is known about the impact of changes in behaviours, beliefs, and attitudes – known as acculturation – on the cardiovascular health of Chinese immigrants, who are one of the fastest growing populations in western countries."

This study examined the association between acculturation and cardiovascular risk factors among Chinese immigrants in Australia, where they are the third largest foreign-born group.

The researchers used data from the 45 and Up Study, a population-based prospective cohort study of 266,696 New South Wales residents aged 45 years and older. This analysis included the 3,220 participants who reported Chinese as their sole ancestry and were born outside of Australia.

Three factors were examined as markers for acculturation: age at migration, length of residence in Australia, and other language spoken at home. Six cardiovascular risk factors were assessed: hypertension, diabetes, high cholesterol, current smoking, overweight/obesity, and physical inactivity.

The average age of Chinese immigrants was 59 years and 56% were women. Nearly 95% had immigrated to Australia in adulthood. Most had lived in Australia for more than ten years and spoke a language other than English at home.

The researchers found that Chinese immigrants who migrated at a younger age, or had lived in Australia for a longer time, had a worse cardiovascular risk factor profile. Risk factor levels were not different between immigrants who spoke English at home and those who spoke another language at home.

Chinese immigrants who migrated as a child or adolescent were 71% more likely to have diabetes, 49% more likely to be overweight or obese, and 47% more likely to have three or more cardiovascular risk factors than those who migrated as an adult.

Immigrants who had lived in Australia for 30 years or longer were 84% more likely to have diabetes and three or more cardiovascular risk factors compared to those who had lived in Australia for less than ten years.

The association between length of residence and cardiovascular risk factors varied between men and women. For example, men become more physically inactive with increasing length of residence whereas women become less physically inactive.

Miss Jin said: "Our study shows that a greater level of acculturation is associated with a worse cardiovascular risk profile, particularly overweight, obesity, and diabetes. Chinese people who migrate as children or adolescents are more susceptible to acquiring risk factors, and susceptibility increases with length of residence."

"Acculturation to western lifestyles includes adopting an unhealthy diet, with increasing consumption of processed food, saturated fat, sugars and soft drinks," continued Miss Jin. "These changes, as well as exposure to western lifestyles at an early age, may predispose immigrants to obesity and diabetes."

She concluded: "Greater awareness is needed among clinicians and policymakers about the risk of cardiovascular disease in the Chinese community living abroad. Our results might be used to help predict the risk of future cardiovascular events among Chinese immigrants and develop preventative interventions."