Americans Living Longer, Better Lives Fewer Suffering From Chronic Disease, Living In Nursing Homes

Living well isn’t just the best revenge, it’s increasingly the happy fate of older Americans whose rising life expectancy, scientists say, is giving them not only more years, but more good years.

That was the conclusion of researchers who reported Friday in the journal Science that growing longevity - from 47 years for a child born in 1900 to 76 years for one born today - has meant a healthier, more enjoyable life for most elders. Many had feared that longer life spans would mean more years of sickness and dependence.

“We are living not only longer, but apparently better and certainly healthier,” said Dr. John W. Rowe, president of the Mount Sinai School of Medicine and Mount Sinai Hospital in New York, and the author of an editorial that accompanied three major research papers on aging in the journal Science.

The new view of aging suggests not only that the later years can be good ones, but also that individuals have considerable control over how long they live and how well they age. Our lifestyles, diet and other “environmental” factors are now believed to account for 65 percent of longevity, with genes determining about 35 percent, notes one paper.

And that control may be fine-tuned as science gains understanding of the way hormones affect aging. Scientists now recognize that the decline of hormones such as estrogen, testosterone, human growth hormone, and DHEA-S is critical to the process, though they are not sure that supplements of these hormones are safe or effective, another paper reports.

In the third paper, researchers tease apart the differences between Alzheimer’s disease and normal, age-related memory loss. Nerve cells in the brain die off in Alzheimer’s, they note, but not in normal aging, which involves potentially reversible changes in the receptors on brain cells.

Overall, there is growing evidence that “aging in America is changing quite dramatically,” Rowe said in a telephone interview.

The prevalence of several chronic diseases, including dementia, hypertension and emphysema, is declining, he noted. Among people 65 to 74, 89 percent have no disability. Even after age 85, 40 percent of the population is fully functional.

And the popular view that older people inevitably wind up in nursing homes is just plain wrong. The proportion of older people living in nursing homes has dropped from 6.3 percent in 1982 to 5.2 percent today.

Genes do play a role in how long people live, of course, said Rudolph E. Tanzi, director of the genetics and aging unit at Massachusetts General Hospital and co-author of the paper on the genetics of aging.

Some genes seem to promote longevity by making proteins that cells can use when they are under biological stress, Tanzi said. And the more protected a person is genetically against diseases such as cancer, heart disease, stroke and diabetes, the better the chances of making it to age 80 or so. Once someone makes it that far, he noted, the role of genetics seems to decrease.

“This is a very encouraging conclusion because as you get past the age-related diseases, we could have the expectation of living quite a long time.”

As for those forgetful moments that make even the middle-aged anxious, John H. Morrison, director of the neurobiology of aging department at the Mount Sinai School of Medicine and a co-author of the paper on memory loss, said researchers are getting better at distinguishing between normal memory loss and Alzheimer’s.

If someone is having trouble recalling names and this does not convert to more severe memory problems, he noted, that’s probably normal aging. On the other hand, if they get disoriented in their own home or town and can’t learn new things, it may be Alzheimer’s.