Treating Ageing to Extend a Healthy Lifespan
Life expectancy has increased remarkably in the last few decades. The number of people living to or even beyond age 100 is expected to increase. This puts ageing at centre stage alongside healthy life expectancy – meaning the years an ageing person can expect to continue living in good health.
At the Society of Actuaries (SOA) Living to 100 Symposium, researchers share ideas and knowledge about ageing and its implications for social and financial systems. At last January’s meeting, several speakers discussed the idea of treating the underlying causes of ageing itself to help delay the onset of age-related diseases.
Professor Nir Barzilai, Director of the Institute for Aging Research at the Albert Einstein College of Medicine, explained that ageing itself is the strongest risk factor for all age-related diseases, and that an individual’s genes and environment only determine which disease occurs first. Individuals with exceptional longevity manifest delayed onset of age-associated disease. Instead of fighting one disease at a time, we could instead fight the ageing process itself. Barzilai explained how the TAME study showed Metformin, a drug for treating type 2 diabetes, delayed ageing effects in nematodes and mice. The study also aimed to get the U.S. Food and Drug Administration (FDA) to classify ageing as a disease, and thus a target for pharmaceutical companies’ research.
Judith Campisi, professor of biogerontology at the Buck Institute for Research on Aging, presented research linking age-related degeneration with cancer and cellular senescence. The research partly concerns a tumour suppressor mechanism that stops cells from dividing, thus preventing cancer. But what is good for young people may be unhelpful in older individuals. Cellular senescence is linked to secreting molecules that can have profound effect on neighbouring cells and therefore actually drive ageing. As we accumulate senescent cells during our lifetime, the risk for all major age-related diseases and cancer increases. Campisi explained that pharmacological interventions that manipulate this process could have the potential to extend the years of healthy life.
The symposium also addressed deterioration in mortality rate. After a steady increase in life expectancy for decades, mortality improvements have slowed significantly. Mortality has even increased in the UK between 2014 and 2015, and a similar dampening of improvements has been observed in the U.S. and Canada. The reasons are unclear and can’t be generalised, but include a spike in mortality linked to influenza and respiratory diseases, increased mortality from dementia, and accidents involving substance abuse and self-harm. Particularly worth mentioning is the opioid epidemic in the U.S. and Canada, which has led to the highest increase in mortality rates among middle-aged people regardless of origin and race.
Whether these mortality findings have implications for the longer term or this is just a temporary drop in the steady increase of life expectancy, open questions remain that must be addressed over the next few years.