We know that people are living longer, but simply measuring life expectancy doesn’t tell us anything about the quality of life that older people are experiencing. In this research, Professor Carol Jagger and her team are using longitudinal data to assess how much of this increased life expectancy is spent with disability – and whether changes are seen across the population, or are affected by deprivation.
There is a huge difference between the least and most deprived socioeconomic groups, and all the gains have been made in the most advantagedProfessor Carol Jagger
To understand how to best support an ageing population, it’s important not only to know how long people are living (life expectancy) but also whether these extra years are spent with a good quality of life.
We wanted to understand the changes in life expectancy in relation to disability or loss of independence, to build a fuller picture of what is happening in the lives of older people. From previous research we knew that, especially for women, although life expectancy had increased so had the length of time that women lived with mild disability. But were some women ageing better than others?
Using longitudinal data from the Cognitive Function and Ageing Studies (CFAS I and II) of people aged 65 years and over, which were gathered in 1991 and 2011, we are looking at the changes in life expectancy and health in older age between those dates. In addition, we are investigating differences between those living in more or less deprived areas.
To my mind this sets the scene for what will be a growing inequality. We think this difference will continue to increase, and needs to be addressed by policy changesDr Andrew Kingston
As with a lot of research, our project has been disrupted by COVID-19. But the Dunhill Medical Trust was fantastic at the start of the pandemic, and came to us very quickly to say “what can we do?”. That was reassuring and allowed us to focus on our work.
Extra years of health or disability?
So far our research has found that, in the 20 years covered by the data, both men and women overall gained more years of disability-free life than years spent living with disability. Positively, the overall percentage of life spent disability-free from age 65 onwards remains high for men (75%) and has increased slightly for women from 56% to 60%.
In order to understand more about how life expectancy and quality of life are changing we developed a new statistical measure, which we called DFLE50%. This measures the age at which half of a person’s remaining years can be expected to be free of disability, and half are expected to be lived with disability.
According to our analysis, the age at which people reach the DFLE50% point rose for both men and women – from 79 to 82 years for men and 68 to 71 for women – suggesting that older people today are enjoying more years of good quality life than in the past.
Inequality of outcomes
However, these gains in disability-free life expectancy weren’t seen uniformly across the population. There is a huge difference between the least and most deprived socioeconomic groups, and all the gains have been made in the most advantaged.
For example, the DFLE50% for the most socioeconomically advantaged women increased by five years over the 20 year study period, yet reduced by one year in the least advantaged.
Our project will continue to investigate these trends, including understanding which types of disability are increasing and the effects of social inequality.
My co-researcher Dr Andrew Kingston says, “To my mind this sets the scene for what will be a growing inequality. We think this difference will continue to increase, and needs to be addressed by policy changes.”
Ultimately, disability and dependence in older age is not inevitable, and we need to improve the chances of everyone ageing well. As Andrew says, “People can be educated to know that ageing is malleable, it’s not just ‘something that happens’ at the end of life.”
Find out more
Our paper in the International Journal of Epidemiology, which aimed to better understand how changes in disability-free life expectancy differ by socioeconomic status, can be read here.