An interesting commentary in NATURE provides an overview of the concept that modern medicine should be seeking to increase the ‘healthspan’ rather than addressing individual diseases one by one. Since many diseases are linked to the gradual debilitation associated with old age, the thought is that by blocking those degenerative changes overall health, and perhaps even lifespan, will be enhanced.
Certainly studies in animals have begun to reveal the molecular underpinnings of degeneration during ageing. Thus the mTOR signaling system, telomerase, and damage mediated by free radical triggered inflammation are all clearly important. Drugs such as rapamycin that affect the mTOR system have been shown to extend lifetimes and ‘healthspans’ in animals. Despite this progress at the laboratory level there are many obstacles to implementing these concepts and approaches in clinical practice.
One is funding. Research on ageing per se receives a tiny fraction of that received by cancer or cardiovascular disease research. Another is the lack of good tools and models that would allow study of ageing processes in animals in a manner parallel to the approaches used to evaluate ageing in humans. Since ageing studies can obviously be of very long duration, good surrogate markers would also be important. Finally our entire health care system is set up to be disease and procedure oriented rather than focusing on promoting the overall health of the individual.