Lucky genes seen as key to long life

Becoming a centenarian may be more a matter of DNA than doing the right thing.

“Some of these people have atrocious lifestyles; the most important factor is genetics,” said S. Jay Olshansky, a professor of public health at the University of Illinois at Chicago. “You have to win the lottery at birth to have any chance to live that long.”

In a classic example, he referred to Frenchwoman Jeanne Louis Calment, who lived to be 122 years old before passing away in 1997.

“She smoked for 100 years — and that makes things interesting: What is it that was protecting her from something that would kill the rest of us?” he asked.

Mr. Olshansky is one of a number of scientists and academics gearing up to tackle the longevity puzzle next month at the Society of Actuaries’ “Living to 100” research symposium, an event that takes place every three years and showcases the top new findings from actuaries, biologists and gerontologists.

Based on his paper “Aging and Health Disparities in America in the 21st Century,” Mr. Olshansky will discuss discovering the biological secrets of living as long as we do, as well as the secret to slowing the aging process.

BIOLOGICAL INDICATOR

In his latest research, Mr. Olshansky discovered that a species’ reproductive cycle is a biological indicator of longevity.

Those with short reproductive windows have short lives, while animals that go through puberty late and have long reproductive windows have lengthier life spans, he explained. The correlation seems to apply within species, as well, so that women who begin menopause late will probably live longer than those who go through it early, Mr. Olshansky said.

But he isn’t the only one whose research is turning up unexpected conclusions. What about findings that working longer can lead to a longer life or that while women live longer, they also can expect to be sick for longer periods?

An analysis of the RP-2000 Mortality Study, a set of mortality tables, seems to suggest that working during retirement is correlated with longer lives, said Steve Vernon, actuary and president of Rest-of-Life Communications.

The numbers show that death rates are 60% higher among men 50 to 70 who aren’t working, versus those who are. At 60, one out of 200 men still working can be expected to die, the data showed, compared with a death rate of 1.6 for every 200 retirees.

Exactly why working longer seems linked to living longer is difficult to pinpoint, Mr. Vernon said. “Emerging evidence is showing that if you’re engaged in life in some way, you tend to keep faculties — and working is another way,” he added.

Another study, written by actuaries Faye S. Albert, John M. Bragg and James C. Brooks Jr. for the last “Living to 100” symposium, revealed that women have longer periods of poor health than men.

The paper, “Health Expectancy,” revealed that men of 75 have a 71.6% probability of remaining healthy over a two-year period. In comparison, women at the same age have just a 67.1% likelihood of staying healthy over the same interval. The disparity holds all the way up to 95; women that age have a 37% likelihood of staying healthy over a two-year period then, compared with 39.3% for men.

Though women tend to live longer lives, it seems they’re more likely to spend those later years sick, said Anna M. Rappaport, founder of an eponymous consultancy, who heads the Society of Actuaries’ Committee on Post-Retirement Needs and Risks.

Such findings stress the need for long-term-care insurance, particularly for women.

“Married women are the survivors, and you can expect a period of widowhood of five to 10 years at the end of your life,” Mr. Vernon noted.

OBESITY THE WILD CARD

Actuaries pointed out that obesity is the wild card in the latest life expectancy studies, even as improving medical technology and declining smoking rates help reduce mortality.

“In general, we continue to see improving longevity, but the one factor that might turn that around and cause that to reverse is obesity,” said Steven I. Schreiber, principal and consulting actuary at Milliman Inc.

Still, genetics have a role in those determinations. “My parents are alive at 90 and 95,” said Mr. Olshansky, who said he expects to live beyond his 90th birthday. “I’m 56 now, and there’s a long distance between where I am now and how much I have to cover when and if I retire.”

E-mail Darla Mercado at [email protected].