Memory lapses are common and increase with age; when do they signal Alzheimer's?
Tuesday, February 9, 2010
Where did I park my car?
What is that lady's name?
Where are my glasses?
Some call these "senior moments" or "tip-of-the-tongue" experiences. They're mundane for many elderly (and not-so-elderly) adults, but when do they become something more serious? How does one know when it's time to get screened for a memory disorder?
"The reason it's becoming such an acute concern for everybody is that baby boomers are starting to get into the higher-risk age group, but the bigger driver for this is the baby boomers' parents," says James Lah, an Emory University neurologist, who is 48 and has parents ages 73 and 81. "That age bracket is very high risk, and seeing it in our parents makes you acutely aware and afraid of that prospect."
The risk of mild cognitive disorder and dementia increase with age; Alzheimer's disease is the leading cause of dementia. About 5 million Americans live with Alzheimer's and, in 2008, it passed diabetes to become the sixth-leading cause of death in this country, according to the Centers for Disease Control and Prevention, partially because of the lack of treatments to stop or reverse it. Some studies estimate that a person's risk of developing the disease doubles every five years after age 65.
Memory lapses start in our 20s, though people don't typically notice or fret about them until their 50s. In a study published last year in the journal Neurobiology of Aging, psychologists asked about 2,000 participants to solve puzzles, identify patterns and remember words and details from stories, among other memory tests. The top performers were 22 years old; researchers saw a notable decline in the ability to make rapid comparisons, remember unrelated information and detect relationships by age 27. A weakening memory can usually be detected by around age 37, according to the study. The good news was that people's vocabulary and general knowledge increase until at least age 60.
"Once you hit your 40s and especially your 50s, your memory is not as good as it used to be," says Gary Small, a professor of psychiatry and aging at the University of California at Los Angeles. "The brain science of aging certainly backs that up."
While it's not healthy to over-interpret everyday memory lapses, it's important to bring up with a doctor anything that strikes you or your family as unusual. It's also wise to do this sooner rather than later, because treatments for Alzheimer's, though not completely effective, may provide some help when the disease is diagnosed early. Also, a doctor can screen a patient for other conditions that can cause memory loss, such as stroke, a bad interaction among medications or a thyroid disorder.
More common conditions such as depression, hormonal changes, stress, fatigue and a poor diet can contribute to forgetfulness, so sometimes lifestyle changes can restore memory function. The strongest memory-protective lifestyle strategy is physical exercise, Small says. Just 10 minutes of brisk walking each day can help lower one's Alzheimer's risk, he says. Lah says his male patients uniformly hate his suggestion to take up ballroom dancing, which is more likely to protect against dementia than, say, golf, because it is more physically demanding and requires a more active thought process.
"It's always good for a giggle during an otherwise difficult discussion," he says.
Some people turn to "brain calisthenics" such as crossword puzzles, playing music or learning a new language to stay sharp. A study published last year in the journal Neurology backed up this approach: Scientists found that people who did 11 such activities a week delayed rapid memory loss by about 1.3 years compared with those who did just four a week. Still, both Small and Lah say it's a stretch to claim that any of the brain exercise programs are proven to prevent memory disorders.