Mortality differentials 1991-2005 by self-reported ethnicity: findings from the ONS Longitudinal Study.

BACKGROUND: Research on ethnic differentials in mortality in England and Wales has focused on immigrants because, until now, studies collecting data on ethnicity have not covered sufficient deaths to investigate the subject. International migrants are selected for good health and tend to have low mortality. METHODS: We investigated all-cause mortality at ages 1-79 in 1991-2005 by self-reported ethnicity and country of birth. The data are from the Office for National Statistics Longitudinal Study of England and Wales for the cohort aged 0-64 in 1991 (n=436 195). Poisson regression was used to adjust the estimates for metropolitan residence and three indicators of socioeconomic status. RESULTS: White, Black Caribbean, Other Asian and Other immigrants all had lower mortality than Whites born in the UK. Indian, Pakistani, Bangladeshi and Chinese immigrants had lower mortality than the UK-born Whites living in similar circumstances to them. By contrast, the UK-born Black Caribbean group had higher mortality (RR=1.38, 95% CI 1.03 to 1.86) than the UK-born Whites. This excess mortality was accounted for by their low socioeconomic status. Within the Black Caribbean population, the UK-born individuals had significantly higher mortality than those born abroad whether or not the estimates were adjusted for socioeconomic status and metropolitan residence. Adjusting exposure time for undocumented emigration made little difference to the estimates. CONCLUSIONS: Immigrants are selected for good health. This has offset the impact of socioeconomic disadvantage on the mortality of minority ethnic groups. As the immigrant population ages and the UK-born minority ethnic population grows, ethnic differentials in all-cause mortality are likely to change.