Affluent men in the UK saw their average life expectancy increase by 17 weeks between 2011 and 2015 more than any other group, according to a report published today by the PLSA.
This is expected to have significant implications for defined benefit (DB) pension schemes, with over half of their liabilities projected to come from people in this 'comfortable' social group.
"The research highlights that 'one size does not fit all' and that using standard actuarial projections may lead to misleading funding assumptions," PLSA director of external affairs, Graham Vidler, said.
"Clearly, a scheme with a high proportion of more affluent members might need to make more provision than a scheme with a more mixed demographic."
The report defines those in the 'comfortable' group as having retirement income of over £7,500 per year, or £5,000 if they live in the least deprived parts of the UK.
It also identifies a 'making-do' group of people with modest retirement income, living in areas of average to low levels of deprivation, and a 'hard-pressed' group of people living in deprived areas on low income.
The increases in longevity for men in the 'comfortable group' continue trends seen in the previous ten years, however, males from outside this group saw their life expectancy stagnate between 2011 and 2015.
Women in the 'comfortable/making-do' groups saw their life expectancy increase by four weeks during that time, and by nine weeks for those in the 'hard-pressed group'.
"It is impossible to say definitively what is causing this disparity," Club Vita head of research, Steven Baxter said. "It could be due to one off events such an especially harsh winter.
"It could also be the impact of austerity measures making life a bit harder for those who don't have as easy access to support networks, or alternative resources to buffer them from changes in the social care system.
"In reality it will be caused by a combination of all of these types of elements. What is certain, though, is that the 'comfortable' group are proving to be more resilient."
This comes after it was found earlier this year that there has been an overall slowdown in improving life expectancy in the UK, compared with at the start of the century, with experts unsure whether this trend will continue or not.