Cardiorespiratory disease mortality among British and Norwegian migrants to the United States.

Mortality rates for coronary heart disease (CHD), chronic non-specific lung disease (CNSLD), and lung cancer for ages 45-74 years were studied for British and Norwegian migrants to the U.S. and for sample of U.S. native-born. The observed order for CHD and lung cancer was as anticipated, with native-born experiencing the highest CHD rate, British migrants the highest lung cancer rate, and, in each instance, Norwegian migrants experiencing the lowest rates. For CNSLD, contrary to national comparisons, the British migrant rates were about equal to the U.S. native-born although Norwegian migrant rates were lowest, as expected. Migrants who were younger than 15 years of age at migration experienced the highest CHD mortality levels, but a decreasing gradient in mortality level with increasing age at migration did not materialize. Due to inherent limitations in the data, results for CNSLD and lung cancer mortality levels with respect to age at migration remain uncertain. Data on cigarette smoking status indicated substantial excess mortality for cigarette smokers compared to non-smokers and occasional smokers for all groups studied.