"I guess I don't so much mind being old, as I mind being fat and old." — Peter Gabriel
Our rising life expectancy has been nice for those who like being alive, but it seems a bummer for society as a whole. Even if Social Security doesn’t go bust as baby boomers slowly saunter into the sunset, their massive Medicare costs seem likely to crush the economy. Not surprisingly, further major gains in longevity, which researchers on aging have recently achieved with drugs in animals, is about the last thing deficit-obsessed policymakers want to see happen. Accordingly, less than 0.5 percent of the National Institutes on Health’s annual budget is allotted to basic research on aging.
But the idea that anti-aging researchers are tinkering with an economic Frankenstein’s monster rests on a conventional wisdom that is actually a mass hallucination — namely, the notion that when people live longer, they rack up greater health care costs.
Here are the facts: People who live an unusually long time tend to be healthier during their later years than shorter-lived people. That means longer-lived ones typically have lower medical costs during their golden years. This health dividend more than offsets the health care costs they accrue by outliving less healthy people.
The proof came out in 2003 in the New England Journal of Medicine. Analyzing Medicare data, federal researchers showed that elderly people in good shape at age 70 — meaning they had no difficulties performing tasks of daily living such as walking and shopping — could expect to live to 84.3, and after 70 they had average, cumulative health care bills totaling $136,000. In contrast, less healthy 70-year-olds with at least one limitation in daily-living activities could expect to live to 81.6 — nearly three years less — yet had cumulative medical bills of about $145,000 during their shorter remaining lives.
Thus, boosting longevity with anti-aging medicines might well lower Medicare expenses on a per-capita basis. Indeed, the three lifespan-boosting interventions known to work in animals — very low-calorie diets (calorie restriction), certain gene mutations and chronic doses of certain drugs, most convincingly rapamycin — expand the amount of time animals spend in good health during their lives.
Unfortunately, there’s a giant exception to the rule that the longer life tends to be a healthier one: Obese people are living longer, thanks to factors such as cholesterol-cutting medicines (as is the entire population), but much of their extra time is spent in ill health, and as a result, their annual medical bills are some 42 percent higher than those of normal-weight people. In fact, the obesity epidemic has greatly increased the prevalence of chronic diseases such as diabetes, but contrary to much of the media coverage on the epidemic, it has had little effect on mortality rates. As the title of one study put it, “Smoking kills, obesity disables.”
Even if rising obesity rates top out — and that may happen, now that more than a third of U.S. adults are obese — the associated medical costs will become much heavier in coming years as people with obesity-associated diseases get older and sicker. Tens of millions of pot-bellied boomers entering their Medicare years is not a pretty sight from a medical economist’s perspective.
The CDC recently attributed $147 billion a year in U.S. medical costs to obesity — over 9 percent of all U.S. health care spending. The nation’s obesity bills are just beginning to ramp up, though, and will soon be growing at a pace comparable to the increase in government medical spending due to the graying of boomers. Annual obesity-related health care costs are projected to rise by nearly $265 billion a year between 2008 and 2018, while annual Medicare expenditures are expected to increase by about $360 billion during the same period. And much of the rise in Medicare spending will go toward treating obesity-related diseases. As one researcher noted, when it comes to chronic health problems, being obese is roughly equivalent to being aged by 20 years.
You might think that anti-aging drugs, like conventional medicines, would only increase these expenses by effectively increasing morbidity faster than mortality. But if obesity essentially accelerates aging, medicines that brake aging are precisely what the doctor should order (along with exercise and eating right). Indeed, longevity-boosting agents that work in animals, such as rapamycin, appear to mimic the effects of calorie restriction, and thus induce metabolic changes very much like those caused by stringent, long-term dieting — which is what calorie restriction is. (Calorie restriction has been shown to increase healthy lifespan by 30 percent or more across a wide range of species.) That suggests such drugs, if proved safe to take chronically as preventive medicines, would have unprecedented efficacy in ameliorating or warding off obesity-associated diseases, regardless of whether they induce weight loss.
Supporting this argument, metformin, a diabetes drug that steadies blood-sugar levels in people and mimics the effects of calorie restriction on gene activity in mice, has been shown to extend healthy lifespan in nondiabetic rodents. More than 50 million prescriptions for metformin are written annually in the U.S. This means the anti-aging revolution may already have been accidentally launched — years from now, we may discover that long-term use of metformin by diabetics has increased their healthy lifespan far more than can be explained by its effect on their blood sugar levels. (Which is what you’d expect from a drug that brakes aging, and thus delays or averts diseases of aging.) There’s already evidence that people on metformin have lower risk of cancer, dementia, heart failure and other diseases of aging.
Peter Gabriel had it almost right: What’s truly bad about getting old is getting old and sick. Aging science has shown a way to mitigate this sad conjunction more effectively than any other medical advance on the horizon.
As a society, however, we’ve shown little interest in pursuing this "longevity dividend"— not surprising, given anti-aging research’s Frankenstein rap. And that’s more than a little ironic, given that no pursuit better serves both our instinctive self-interest and the larger interests of society than attempting to buy us quality time — extra years spent in good health — as cheaply as possible.