European societies are living longer but as the older population increases, are these extra years healthy ones?
Research we recently published in The Lancet suggests that the answer to this question crucially depends on what you mean by “healthy”. For some health measures such as cognitive impairment, which includes problems such as memory loss and an inability to learn new things, we found that these extra years are indeed healthy. But according to other measures these extra years are also increasingly being spent with disability, although this is with milder levels of disability rather than severe.
A look at the numbers
Our research used the Cognitive Function and Ageing Studies where two groups of older people aged 65 and above were interviewed in 1991 and 2011. We looked at three health measures: cognitive impairment (rated none, mild, moderate-severe); disability in activities of daily living (rated none, mild, moderate-severe); and self-perceived health (rated poor, fair, excellent-good).
In this 20-year period, life expectancy of women in these groups aged 65 grew by 3.6 years (from 16.7 years to 20.3 years), an average of the remaining years lived. For men on the other hand, life expectancy grew by 4.5 years (from 13 years to 17.5 years).
Looking at cognitive impairment, we found that these gains were accompanied by gains in years free of any cognitive impairment (4.4 years for women and 4.2 years for men). For disability, a physical health measure, the results were not so good. Yet, men appeared to have fared better. Over the 20-year period men aged 65 gained 2.6 years free of disability, while women of the same age gained only six months. In both cases the proportion of life spent without disability had reduced over the period.
Because of the way we measured disability, through difficulty with activities of daily living, we could classify whether the disability was mild or more severe. Teasing out the results further, we found that the gains in years with disability were predominantly gains in mild disability. At age 65, we found that women were spending around 2.5 years more with mild disability and around seven months more with moderate or severe disability. Men on the other hand, were spending only 1.3 years more with mild disability and six months more with moderate or severe disability.
Our two studies also included self-perceived health, a more holistic health measure that is used by the Office for National Statistics when determining healthy life expectancy estimates. From our study we found that the proportion of reported life spent healthy at age 65 had risen by three to four percentage points for men and women. It is a very slight increase, but a significant one.
So what does this all tell us? That British people are living longer and healthier, especially in the mind, but with some less positive trends with regard to mild disability.
Why do the numbers matter?
One reason why mild disability has risen may be because of a rise in obesity levels over the last decades across this age group. It is well known that women in general have a higher prevalence of disability, but they also suffer more multiple diseases. For example, another study reportedthat women aged 85 had on average five diseases compared to men of the same age who had four.
If older people are living longer and healthier, then this has considerable implications for government, employers, individuals and society in terms of the economy, housing and extending working life. But our studies provide estimates of time spent with cognitive impairment (just under ten months for women and four months for men on average from any age) and more severe disability (around two years for men and three years for women). These estimates are particularly important for making policies around elderly care and could provide a basis for costing future care provision. There are other factors that will need to be considered too, including which specific diseases might be responsible for the rise in disability and whether inequalities between social groups have also widened over the period.