We talk about some grim stuff in this space, so when a bit of good news surfaces about aging, we want to celebrate.
And this recent report from Denmark does sound promising. Researchers there compared two groups of nonagenarians born 10 years apart and found that not only did those born in 1915 live longer than those born in 1910, but they also scored significantly better on cognitive tests and measures of mobility.
“The new generation of very old people in Denmark is functioning at a much higher level,” said Dr. Kaare Christensen, lead author of the new study and an epidemiologist at the University of Southern Denmark.
You can see why this deserves two cheers, though maybe not three. Scientists here and elsewhere continue to ponder the impact of our extended lifespans. Do we rejoice because people over age 80 represent the fastest-growing segment of the American population? Or fret because longer lives frequently also mean years of illness and disability, with an increasing risk of dementia? We would all fret less if the characteristics of age began to change, so that 90 really was the new 80.
In these two cohorts, drawn from everyone born in that year and still living in Denmark and tested in 1998 and in 2010, that appears to have happened. The chance of surviving to age 95 was nearly a third higher among those born in 1915, compared with the 1905 group. But those old people didn’t reflect fears that more years mean more sickness or disability.
Even though they were two years older at the time of testing, the later-born subjects got significantly higher scores on two types of cognitive tests, and the proportion who got the highest scores nearly doubled, to 23 percent from 13 percent. They also scored better on a scale that measured their mobility, though tests showed no difference in physical strength or speed.
Why would 95-year-old Danes born in 1915 do better than 93-year-olds born in 1905, especially if they were older when they were tested? Education has a known association with cognitive ability, but it didn’t play a major role in these differences, Dr. Christensen said. Nor did some major historical event — a famine, say, or two World Wars — provide an explanation.
Instead, he said, “the later cohort had a lot of things on their side that we can’t disentangle,” like better diet and living conditions, improved medical care, a stronger economy, more stimulation from sources like radio and television. And though they were not physically more robust, they reported less difficulty in getting around, possibly because of better adaptive equipment. They benefited, Dr. Christensen said, from “a better head and a better environment.”
Another study appearing in the The Lancet found that in England and Wales, dementia rates in a sample of those over age 65 had dropped by a quarter over the past two decades.
“If we use today’s 90-year-olds to forecast future care needs, we might be unduly pessimistic,” Dr. Christensen said. “It’s possible to increase the number of people who live to very old ages and at the same time have them function better.”
Didn’t I just post, a few days ago, about pervasive disability in the elderly, about rates rising with age until most people past 90 are disabled? I did, and both these findings can be true.
The University of California, San Francisco, study I cited used federal data to examine the final two years of life in people over age 50. And it didn’t include dementia, which surely would have increased the proportion of people unable to function independently.
By focusing on people healthy enough to survive into their 90s, the Danish study eliminated the many people with chronic diseases and disabilities who had already died at younger ages.
More importantly, when you look more closely at the data, the elderly Danes were contending with their share of health problems and dependence, as Dr. Christensen acknowledged. “We’re not saying that at 90, you’re as fresh as a young person,” he said. “It’s still a challenge to be 90.”
Of the nearly 1,600 people in the later cohort, for instance, about 40 percent demonstrated mild to severe dementia, scoring below normal on cognitive tests. In fact, 20 percent of both groups were too mentally or physically disabled to participate, so the researchers interviewed a proxy, like a family member. About half the people in both groups were living in some sort of care facility. They weren’t Superdanes.
And how to calculate the role of the country itself, with its Scandinavian-style welfare system? “It’s not Wonderland,” Dr. Christensen said, but he noted that these seniors had known nearly lifelong national health care, pensions that helped them avoid poverty, and subsidized housing and nursing care. Maybe the bottom line is that we’d do better if we moved to Denmark.
Nor do we know if these improvements will continue for those born in 1925 or 1945.
What the Danish and English studies do show, though, is that the phase of life we label old age can get better over time, even for the very old. That the environment has an impact and the environment can change. That, as Dr. Christensen said, “we are moving in the right direction.”
A better head and a better environment. Yes, we can applaud that.
Paula Span is the author of “When the Time Comes: Families With Aging Parents Share Their Struggles and Solutions.”