In Hawai`i we live long, but like elderly everywhere, we're dying faster

Hawai`i leads the nation in longevity, and new research suggests our old-timers are in fact dying faster than theory suggests--and at the same increasing rate as the rest of us.

The new information is contrary to the long-held belief that the mortality curve flattens after age 80. This has significant impacts everywhere, and particularly in a state like Hawai`i, with its high elderly population—and the need to plan for providing services to an elderly population.

Only eight states have residents who can expect, on average to live past 80. Hawai’i is at the top of the list at nearly 81.5 years. The others over octogenarian status are, in order after Hawai`i, Minnesota, California, New York, Connecticut, Massachusetts, North Dakota and Utah. The national average in 2010 was 78.3.

If you’re interested in this sort of data, you might want to look here and here.

It was nearly two centuries ago, in 1825, that a fellow named Benjamin Gompertz calculated that an adult person’s chance of dying in any given year doubled with every added eight years of life. His calculation estimates your chances at about 1 in 100 at age 60, but 1 in 10 by the early 80s.

Researchers quickly found fault with the law, with respect to the very old. And they developed something called the late-life mortality deceleration law. It suggests that your chances of dying don’t keep increasing so quickly beyond age 80—that mortality rates flatten out.

But scientists Leonid A. Gavrilov and Natalia S. Gavrilova, writing in the North American Actuarial Journal, say they compared that theory against the actual data of more than 9 million Americans born during the 20 years from 1875 to 1895.

What they found was that there are far fewer oldsters than most folks expected—just half as many. Making it to 100 years of age turned out to be twice as rare as the U.S. Census has assumed.

“Study of several single-year extinct birth cohorts shows that mortality trajectory at advanced ages follows the Gompertz law up to the ages of 102-105 years without noticeable deceleration,” the authors write.

Or, put more simply: “In our study, we found no significant mortality deceleration at advanced age for humans.” (Interestingly, the superannuation mortality deceleration still holds for insects, but that's another tale.)

The development of the flawed mortality flattening or deceleration theory likely was the result of any number of factors, including mixing birth cohorts, age exaggeration and various other errors, they say.

The findings have serious impacts. All kinds of calculations are based on the assumption of how many elderly will be alive, and how fast they’re dying: retirement planning, annuities, insurance policies, Social Security payments, care home cost projections, an entire range of health care numbers, and lots more.

© Jan TenBruggencate 2012