|Death May Have Parted
s there is a chasm of death toward which we are inexorably sliding? According to demographer Dr. James Vaupel, “There is no fixed lifespan.” (Vaupel is the director of the laboratory of survival and longevity at the Max Planck Institute for Demographic Research in Rostock, Germany.) Why? Because in the world’s healthiest countries, for the last 160 years or so, the expected age of death has increased by about 2.5 years for every decade that has passed. So regular is this pattern that Vaupel wonders whether it can’t continue indefinitely.
Awed by what it implies, we remarked about this phenomenom in an editorial
(“Breaking Through the Life Barrier”) in the July 2002 issue of Life Enhancement. Indeed, if there is a fixed barrier to the extension of human lifespan, then those countries approaching it—those whose populations have succeeded in living the longest—should eventually run aground, slowing down in their progress. Yet this is not happening, according to Vaupel.
On the contrary, in health-advanced Japan, for example, every year adds another quarter of a year to life expectancy. Nor are people dying faster as they reach their 80s and beyond. Once again, on the contrary, “. . . death rates are coming down, faster and faster . . . by about 2% per year in most countries,” says Vaupel. “There is no reason that life expectancy can’t continue to go up two to three years per decade.” This would mean that by mid-century, life expectancies will approach 100 in some countries. Other researchers who share Vaupel’s views predict that life expectancies might be even higher by 2050, possibly approaching 130.
In a recent paper, Vaupel and his colleagues inquired into the established predictions of what causes mortality and especially whether it is a stochastic (meaning random) process in the oldest of the old. Conducted in 1998 with a cohort of 2249 Danes born in 1905, the study measured sociodemographic factors such as marital status, smoking, and alcohol consumption, along with such indices as body mass index, physical and cognitive performance, and health, during visits to the participants’ residences. Regression models were used to evaluate the predictors of mortality.
What the scientists found was that the predictions were invalid to a significant degree. Sociodemographic factors—smoking and obesity in particular—were not readily able to predict continued longevity or its opposite. Instead, a high disability level, poor physical and cognitive performance (in men and women), and self-rated health (in women only) emerged as significant factors in predicting mortality. Interestingly, no direct correspondence was found with education or marital status.
These findings indicate that mortality in the oldest of the old is not the direct consequence of a stochastic process—meaning that mortality is not essentially independent of individual characteristics—meaning that the death rate is not primarily a function of chance events outside an individual’s control.
This conclusion is what we’ve been hoping for all along: that our desire to be more conscious and healthy and to live a longer life depends on our personal efforts. It would appear that the tide of the trend toward more life is rising and that individual actions to enhance our health are paying off.
In a sense, we marry into the world when first we become conscious—we take an oath of fidelity to life. Till death do us part? Perhaps we will get to the point where life expectancy will increase more than one year for each additional year we live. Perhaps then we could live forever. Then there would be no departures, only new beginnings.
- Kolata G. Could we live forever? New York Times, Nov. 11, 2003, p. D6.
- Nybo H, Petersen HC, Gaist D, Jeune B, Andersen K, McGue M, Vaupel JW, Christensen K. Predictors of mortality in 2,249 nonagenarians—the Danish 1905-Cohort Survey. J Am Geriatr Soc 2003 Oct;51(10):1365-73.