The best is yet to be?

Two essays in the latest BMJ* argue along rather similar lines that it is time for a substantial investment in biomedical research into slowing the aging process in humans. (Colin Farrelly authors one of them; a multitude led by Robert Butler of the International Longevity Center presents the other.)

Here is the problem, in a nutshell. Current efforts to combat the various diseases associated with aging, from cancer to heart disease to osteoporosis to Alzheimer's can have, at best, a limited payoff. However well you succeed in saving an old person from death from cancer, you won't gain a great deal in disability-free lifespan because by the time we hit our 70s, comorbidity is the rule. The person also has arthritis, heart disease, cognitive decline. One way to think of it is that these are not diseases of aging, they are aging.

Aging is a global process affecting the organism -- metabolic level, DNA repair, tissue repair, all decline. The immune system becomes less effective. The brain shrinks. Muscles atrophy. We can slow some of these effects to some extent by maintaining a good diet, physical activity, and mental engagement, but we can't stop them. These authors argue that we are getting close enough to understanding the basic biology of aging that the possibility is not far off of a pill that will slow it down. As Farrelly puts it, "If we succeed in slowing ageing [sic -- British spelling] by seven years, the age specific risk of death, frailty and disability will be reduced by about half at every age. People who reach the age of 50 in the future would have the health profile and disease risk of today's 43 year old."

So, consider cancer. A man's risk of being diagnosed with cancer in the next 20 years is 21.4% at age 50 and 34.5% at age 60. Cancer cost $219 billion in the U.S. in 2007, including $89 billion in direct medical costs. So investing even a few billion dollars in anti-aging research, if it reduced the age-adjusted risk of cancer by even a few percent, as the population ages, would seem an extremely cost-effective investment. And how many of us wouldn't want to feel seven years younger?

However, it seems to me that this is not quite such a clear cut ethical question as it might seem. First of all, as I keep repeating, the situation is a lot different in much of the world, where the ills of aging are the least of people's worries, and children are lucky to make it past the age of five. The scourges of infectious and parasitic disease continue to burden children and adults, shortening lives, sapping energy and productivity and leaving whole communities mired in poverty. Of course, money spent on anti-aging research doesn't have to be taken from money that would otherwise be spent on combating tropical diseases and other afflictions of the poor, but as advocates, what should be our priorities?

Second, of course, delay is not elimination. Even if it gets us seven years later, it's still gonna get us. Perhaps it will be a better world if rich Europeans and Americans live to be 90 in stead of 83, and Tom Watson is still finishing in the top ten on the seniors tour when he's 75. I don't know. But think again -- it isn't actually going to save us any money. After seven years, people will have caught up to their previously expected biological age and we'll be back on track with the same levels of disease and disability. We would have been able to bank some dough in the mean time -- savings from Medicare, basically -- but will that actually happen?

In order for this to work, we'll have to re-engineer the life course socially as well as biologically. The expectation that at around age 65, most people will leave the workforce and take up golf, crocheting, and martini drinking on the veranda full-time on the public dole is not going to work -- particularly if they're going to do it for 25 or 30 years.

What might a longer, healthier old age look like, that would truly benefit the old, and the rest of society? Is it really possible? Is it worth pursuing? How would you use a few extra years?

*Subscription only, which normally disqualifies a reference here, but this seemed important enough to violate the rule.