Immigration to the United States is associated with a rise in smoking among Latinos and Asians, a new study suggests.

Researchers from Rice University, Duke University and the University of Southern California examined smoking prevalence and frequency among Asian and Latino U.S. immigrants. The research focuses on how gender differences in smoking behavior are shaped by aspects of acculturation and the original decision to migrate.

"We know that after migrants come to the [United States], their health behavior and health status changes the longer they live in the United States," said Bridget Gorman, lead author of the study and chair and professor of sociology at Rice University. "Our study examined how time spent in the United States, along with other aspects reflective of acculturation to the U.S., relates to smoking behavior among Asian and Latino migrants."

For the study, researchers used a sample of more than 3,000 Asian and Latino migrant adults aged 18 and older.

The study found that smoking prevalence among Asian immigrant men was more than four times that of Asian immigrant women (30.4 percent and 7.1 percent, respectively); among Latino immigrants, men's smoking prevalence was more than twice that of women's (29.5 percent and 12.6 percent, respectively). For smoking frequency, Asian men on average smoked 2.5 more cigarettes per day than Asian women, compared with 1.5 more cigarettes per day that Latino men smoked than Latino women.

They also found that smoking increases with duration of U.S. residence among Asian immigrants (both prevalence and frequency) and among Latino immigrants (frequency only).

Gorman added that independent of time spent in the United States "immigrants who form strong connections to the country through English-language proficiency and citizenship acquisition benefit in terms of reduced smoking." Gorman said this may be because the stresses associated with adapting to the United States have declined; but since both English-language proficiency and citizenship are associated with higher socio-economic standing, this might also indicate that smoking is lower among the most economically well-off migrants.

The findings were recently published Social Science & Medicine.