While most people will live to state pension age and beyond, a large proportion are unlikely to reach the threshold in good healthReuters

Increasing the state pension age without taking into account an 18-year difference in healthy life expectancy across the UK risks disadvantaging groups of older people.

According to a report by the International Longevity Centre (ILC-UK), measures such as healthy life expectancy and disability-free life expectancy vary significantly by region and social class. In consequence, particular groups are more likely to be disadvantaged by a rise in the state pension age (SPA) than others.

The study found that while most people will live to state pension age and beyond, a large proportion are unlikely to reach that threshold in good health. Glasgow, for example, has a healthy life expectancy of just 46.7 years – a near 20-year deficit from the average SPA of 65.

"As we live longer lives it appears to be a natural move to raise the SPA," said Baroness Greengross, chief executive of ILC-UK.

"Yet as the research shows, we need to be very careful to ensure that increasing the state pension age doesn't just result in an increase in the numbers of people out of work and ineligible for state pension."

The research revealed that men in more disadvantaged areas and lower social classes are unlikely to reach state pension age free of disability. Those in the lowest social class have a disability-free life expectancy that is 13.4 years lower than males in the highest social class.

ILC-UK said the additional benefits tied to the state pension age, such as the free bus pass, will on average, not be available to those from lower social classes until well beyond their healthy life expectancy.

The study also found that health gaps were continuing to widen across groups.

The difference in disability-free life expectancy between women born in the most and least deprived areas was 11.6 years in 2001-04 and by 2007-10 it had increased to 13.4, according to the report.

"This research backs up what we've known for some time - that increasing the state pension age based purely on longevity will leave many people facing serious problems in later life," said Caroline Abrahams, charity director at Age UK.

"While it may seem reasonable to consider extending working lives as overall life expectancy increases, it will be especially tough on people with lower life expectancies – who are likely to be on lower incomes – who may end up with little or no time left in retirement to enjoy."