Slowing down the aging process -- the future of disease prevention?

Slowing the ageing process would have a much greater benefit for people's health than traditional medical approaches that target individual disease, say experts on BMJ.com today. Most medical research focuses on preventing and curing individual diseases as if they were independent of one another, but as people in developed nations are living longer they are increasingly experiencing more than one age related disease—comorbidity is now the norm rather than the exception.

Professor S Jay Olshansky and colleagues believe that the effectiveness of the disease-specific approach will become increasingly limited and that even if a "cure" was found for any of the major fatal diseases, it would have only a marginal effect on life expectancy.

They argue that because our susceptibility to disease increases as we grow older, the most efficient approach to combating disease and disability is a "systematic attack on ageing itself."

They suggest that recent advances in understanding the biological mechanisms responsible for ageing, which give rise to most diseases and other age related health problems, means that the time has arrived for this new model of health promotion and disease prevention.

Evidence suggests that all living things, including humans, possess biochemical mechanisms that influence how quickly we age and these are modifiable, say the authors. For example, dietary restriction and genetic alteration have been shown to extend the lifespan of many laboratory organisms including mice, flies and worms, and postpone age related diseases such as cancer, cataracts and cognitive decline.

They call for increased funding to investigate how diseases such as type 2 diabetes, Parkinson's disease and most cancers interact with ageing and for more research into the "fundamental cellular and physiological changes that drive ageing itself", alongside continued research into individual diseases.

Staying healthier for longer has benefits for society as well as individuals, writes Professor Colin Farrelly from the University of Waterloo in Canada, in an accompanying Analysis.

Success in increasing longevity in laboratory organisms has demonstrated that aging is not an irreversible process. If human ageing was slowed by seven years, the age specific risk of death, frailty and disability would be reduced by about half that at every age, claims Farrelly.

The rapid rise in older people over the next few decades will be accompanied by an increase in the number of people with disease and chronic illness and costs are set to rise dramatically. In 2007, cancer cost the US alone an estimated $219bn, including $130bn for lost productivity and $89bn in direct medical costs.

Can we really afford not to tackle ageing, he asks. By extending the healthy lifespan, people would remain in the workforce longer, personal income and savings would flourish, age entitlement programmes would face less pressure and national economies would flourish.

Farrelly concludes that the greatest obstacle will be convincing the general public that slowing ageing is feasible and deserving of a larger share of the funds available for scientific research.

Source: BMJ-British Medical Journal