1 A investigation of ethnic variations in mortality using the ONS Longitudinal Study Chris White Health Variations Team Office for National Statistics

2 National targets on health inequalities –Infant mortality by socioeconomic status –Life expectancy by geographical area Ethnicity as a dimension of inequality –Increasingly diverse UK population –Race Relations Amendment Act –Existing research evidence –Explanatory paradigms of ethnicity/health relationship Background

3 Source: Census April 1991 and 2001

4 Health indicators Bangladeshi, Pakistani and Irish men have 10-70% more limiting long-term illness than non-Irish White men Higher rates of ischaemic heart disease in Indian, Bangladeshi and Irish men and higher rates of stroke in Black Caribbean, Indian and Bangladeshi men All minority ethnic groups except Irish men consumed less alcohol than the general population smoking prevalence among Bangladeshi men was twice as high as general population and rates lowest among south asian women Socio-economic determinants –low income –unemployment –deprived areas Sources: Health Survey for England, 1999, Family Resources Survey, 2000/01, Labour Force Survey, 2001/02

5 General Health by Ethnic Group Source: Health Survey for England 1999, Department of Health

6 Use of ethnic group as a classification for mortality analysis Ethnicity is not collected at death registration Country of Birth is collected at death registration and has been used a proxy for ethnicity Country of birth has the disadvantages of: –excluding people from ethnic minority populations born in Britain –including people from european extraction born abroad

7 EVIDENCE FROM PREVIOUS STUDIES Source: Harding and Maxwell Differences in mortality of migrants

8 Evidence from previous studies Source: Wild, S and McKeigue, P, (1997)

9 Ethnicity at the 1991 census and research objective Self-reported ethnicty collected for the first time at 1991 census To investigste th potential of the LS to provide valid mortality comparisons by ethnic group

10 Data Source ONS Longitudinal Study Record linkage study based on 1% sample of the population of England and Wales Data collected since 1971 census Attaches ethnic group collected at 1991 census to births and deaths Useful for mortality analysis

11 STRUCTURE OF THE ONS LONGITUDINAL STUDY

12 Linkage of events requires the LS member to registered with a GP LS members without this attribute will not have events allocated to them for the period of time that this attribute is absent. The quality of the sample for events analysis can be defined by the no trace rate: Tracing Indicators Number ‘not traced’ in subgroup i original sample in subgroup i *100

13 No Trace Rates and Group Samples Source: ONS Longitudinal Study Development Team

14 Methods Analysis time frame census 21/4/1991 to 31/12/1999 Includes embarkations and re-entrants during period First sample - all those present at 1991 census Second sample - all those present at 1971 and 1991 –Allows a 20 year continuous follow up of the sample pre the analysis period Self-reported ethnicity at 1991 census eight group classification Standardised Mortality Ratios using person time denominators

15 Results - 1

16 Results - 2

17 Methodological Issues Large confidence intervals due to small numbers of deaths in each ethnic group Age distribution of ethnic minorities younger than the general population shrinking sample size further and number of deaths Ethnic minority populations have a higher turnover Immigration/emigration data known to be incomplete (monitored via GP (de)registrations) Emigration after retirement and in advanced old age could bias mortality findings

18 Tentative Conclusions There are trends in mortality by ethnic group This may be due to real differences or methodological issues A healthy migrant effect is possible Differences between analyses by ethnic group and those by country of birth may suggest differences between first generation immigrants and those born in Britain Effect of changing social status in longer established ethnic populations needs exploration

19 Future developments More work needed to understand migration patterns, generational differences, and the effects of socioeconomic factors Civil Registration: Vital Change raised prospect of future changes to data collected about vital events National Statistics review of migration statistics may lead to better picture of population movements

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