The authors performed a historical review of cardiovascular risk profiles of Irish immigrants to the United States between 1850–1970, in regard to lifestyle, socioeconomic circumstances and social capital. They analyzed U.S. Census data from 1850–1970, area-based social and epidemiological data from Boston, data from Ireland's National Nutrition Surveillance Centre and literature on Irish migration. The Irish were consistently at increased risk of cardiovascular diseases, a risk that related initially to material deprivation, across the life course of at least two generations.
The principal difference between the Irish and other disadvantaged immigrant groups, such as the Italians, was dietary habits influenced by experiences during the Irish famine. Although there was a psychosocial component to the disadvantage and discrimination they experienced as an ethnic group, the Irish also exhibited strong community networks and support structures that might have been expected to counteract discrimination's negative effects. However, the Irish's high levels of social capital were not protective for cardiovascular disease.