Does playing bridge, which involves both social interaction and mental sharpness, help keep dementia at bay?

The ladies in the card room are playing bridge and, at their age, the game is no hobby. It is a way of life, a daily comfort and challenge. “We play for blood,” says Ruth Cummins, 92. “It’s what keeps us going,” adds Georgia Scott, 99. “It’s where our closest friends are.”

In recent years scientists have become intensely interested in what could be called a super memory club — the fewer than one in 200 who, like Scott and Cummins, have lived past 90 without a trace of dementia. It is a group that, for the first time, is large enough to provide a glimpse into the lucid brain at the furthest reach of human life, and to help researchers tease apart what, exactly, is essential in preserving mental sharpness to the end.

Social component

“These are the most successful agers on earth, and they’re only just beginning to teach us what’s important, in their genes, in their routines, in their lives,” said Dr. Claudia Kawas, a neurologist at the University of California, Irvine. “We think, for example, that it’s very important to use your brain, to keep challenging your mind, but all mental activities may not be equal. We’re seeing some evidence that a social component may be crucial.”

Laguna Woods Village, a sprawling retirement community of 20,000 south of Los Angeles, is at the centre of the world’s largest decades-long study of health and mental acuity in the elderly. Begun by University of Southern California researchers in 1981 and called the 90+ Study, it has included more than 14,000 people aged 65 and older, and more than 1,000 aged 90 or older. Such studies can take years to bear fruit, and the results of this study are starting to alter the way scientists understand the aging brain. The evidence suggests that people who spend long stretches of their days, three hours and more, engrossed in some mental activities like cards may be at reduced risk of developing dementia. Researchers are trying to tease apart cause from effect: Are they active because they are sharp; or sharp because they are active?

At the same time, findings from this and other continuing studies of the very old have provided hints that some genes may help people remain lucid even with brains that show all the biological ravages of Alzheimer’s disease.

In the gated Laguna Woods Village, the residents begin a new life here. They are as busy as arriving freshmen at a new campus, with one large difference: they are less interested in the future, or in the past. “We live for the day,” said Dr. Leon Manheimer, a long-time resident who is in his 90s.

Yet it is precisely that ability to form new memories of the day, the present that usually goes first in dementia cases, studies in Laguna Woods and elsewhere have found. The very old who live among their peers know this intimately, and diagnose each other, based on careful observation. And they have learned to distinguish among different kinds of memory loss, which are manageable and which ominous.

Here at Laguna Woods, many residents make such delicate calculations in one place: the bridge table. Contract bridge requires a strong memory. Good players remember every card played and its significance for the team. Forget a card, or fall behind, and it can cost the team — and the social connection — dearly. “When a partner starts to slip, you can’t trust them,” said Julie Davis, 89, a regular player living in Laguna Woods. “That’s what it comes down to. It’s terrible to say it that way, and worse to watch it happen. But other players get very annoyed. You can’t help yourself.”

Mental engagement

So far, scientists here have found little evidence that diet or exercise affects the risk of dementia in people over 90. But some researchers argue that mental engagement — doing crossword puzzles, reading books — may delay the arrival of symptoms. And social connections, including interaction with friends, may be very important, some suspect. In isolation, a healthy human mind can go blank and quickly become disoriented, psychologists have found.

“There is quite a bit of evidence now suggesting that the more people you have contact with, in your own home or outside, the better you do mentally and physically,” Dr. Kawas said. “Interacting with people regularly, even strangers, uses easily as much brain power as doing puzzles, and it wouldn’t surprise me if this is what it’s all about.” And bridge, she added, provides both kinds of stimulation.

Bridge is a different kind of challenge, but some residents here swear that the very good players can play by instinct even when their memory is dissolving. “I know a man who’s 95, he is starting with dementia and plays bridge, and he forgets hands,” said Marilyn Ruekberg, who lives in Laguna Woods. “I bring him in as a partner anyway and by the end we do exceedingly well. I don’t know how he does it, but he has lots of experience in the game.”

Scientists suspect that some people with deep experience in a game like bridge may be able to draw on reserves to buffer against memory lapses. But there is not enough evidence one way or the other to know.

In studies of the very old, researchers in California, New York, Boston and elsewhere have found clues to that good fortune. For instance, Dr. Kawas’s group has found that some people who are lucid until the end of a very long life have brains that appear riddled with Alzheimer’s disease.

Dr. Nir Barzilai of the Albert Einstein College of Medicine has found that lucid Ashkenazi Jewish centenarians are three times more likely to carry a gene called CETP, which appears to increase the size and amount of so-called good cholesterol particles than peers who succumbed to dementia. “We don’t know how this could be protective?,” Dr. Barzilai said. “And at least it gives us a target for future treatments.”

For those in the super-memory club, that future is too far off to be meaningful. What matters most is continued independence. And that means that, at some point, they have to let go of close friends.

“The first thing you always want to do is run and help them,” Davis said. “But after a while you end up asking yourself: ‘What is my role here? Am I now the caregiver?’ You have to decide how far you’ll go, when you have your own life to live.”

The rhythm of bidding and taking tricks, the easy conversation between hands, the daily game — after almost a century, even for the luckiest in the genetic lottery, it finally ends. “People stop playing,” said Norma Koskoff, another regular player, “and very often when they stop playing, they don’t live much longer.”

©New York Times News Service 2009

Keywords: bridgecard games