Understanding the changing health status and health needs of older people: England and the USA compared

David Melzer, Brenda McWilliams and Elizabeth Gardner, University of Cambridge

[Project number 30023]

The English Longitudinal Study of Ageing is a new national cohort aiming to understand disability, social class differences and factors influencing retirement. ELSA has a sister study in the US (The Health and Retirement Study). ELSA is co-funded by the UK Government and the US National Institute on Aging.

This research project aims to understand the patterns and causes of disability in the ELSA and US studies. A key measure of the burden of disability is 'disability free life expectancy' (DFLE). ELSA is very unusual in having a performance test of mobility for a national population, allowing the first national level estimate of DFLE using an objective measure.

To compute DFLE for older groups within ELSA/England, we need a source of accurate mortality data by age, sex and markers of social position (social class, housing tenure, car ownership, educational qualifications). Being a new study, the ELSA sample will have to be followed up for many years before we can get direct estimates for the study sample itself.

The LS is able to provide age-specific mortality data by social position using the Census and death data. We have previously published estimates based on LS data and the MRC Cognitive Function and Ageing Study (Melzer D et al. Socioeconomic status and the expectation of disability in old age: estimates for England. Journal of Epidemiology and Community Health 2000;54(4):286-92). Using age specific mortality rates, we will be able to calculate DFLE for older people for 1992 to 2001 by different markers of social position. 2001 data may be needed to avoid numerator denominator bias. Disability free life expectancy can be calculated using Sullivan's method.