For people of a certain age, it's not uncommon to seize on any forgetfulness as a symptom of Alzheimer's disease. Lose the car keys, forget a name, read a Top 10 list of dementia's warning signs and the worry begins.
"Even more epidemic than Alzheimer's itself is the fear of Alzheimer's," said Richard Lipton, who heads the Einstein Aging Study at the Albert Einstein College of Medicine in New York.
So in an attempt to offer some perspective, here's another list.
We interviewed three experts: Lipton, who also heads the division of cognitive aging and dementia at Montefiore Medical Center; Ronald C. Petersen, director of the Mayo Clinic's Alzheimer's Disease Research Center; and Heather M. Snyder, director of medical and scientific operations at the nonprofit Alzheimer's Association.
Here are their thoughts about what you should watch for
You shouldn't automatically fret about dementia if your car keys go missing. It's when you start forgetting truly important stuff that you should worry.
"It's also not necessarily forgetting where your keys are - in fact, I don't know where my keys are right now - it's forgetting what keys are for. Or not knowing what a key is for until you put it in your freezer," Snyder says. "It's that type of change in memory."
The Alzheimer's Association's list says you should be concerned about memory loss that disrupts daily life. Lipton goes further, distinguishing between retrieval problems and storage problems. Even a high school student can have trouble retrieving an algebra formula now and then. Such retrieval problems also increase with natural aging. But the key is, the memory is there.
"When you meet somebody at a party, you can't remember their name and then you say to your partner, 'Well, what was that person's name?' and they say, 'Harry Schwartz,' and you say, 'Oh, yeah, that's right,' " Lipton says, "that's not what I would call a primary memory problem. It's a retrieval problem."
That's not a warning sign of Alzheimer's, Lipton says. A warning sign is when you don't remember Harry Schwartz at all.
"And so that's a distinction that these lists often don't often make," Lipton says. "When... you say, 'Oh yeah,' you should also say, 'Oh, thank goodness.' "
Sometimes it's not even a retrieval problem. In today's frenzied, multitasking world, people don't always form memories in the first place. Petersen says focusing more attention on tasks at hand might be more helpful than obsessing over what you can't remember.
Inability to do tasks one used to do well
A person who could never balance his chequebook shouldn't worry if he has trouble doing so at age 65. But a retired accountant who always balanced his checkbook to the penny and no longer can do that might want to see a physician. Difficulty planning and executing familiar tasks can signal deeper cognitive problems.
"Sometimes you get signs that Mom or Grandma has always hosted Thanksgiving dinner, and she just can't do it anymore - she just can't conceptualize getting all the pieces together at the same time," Petersen says. "As people age, they need some help - that's part of normal aging. But when it becomes more than that, and they just can't cope with it, that becomes more worrisome."
Confusion about time or place, or trouble getting around
It's worrisome if a person becomes lost in a familiar place or goes into a grocery store and becomes confused about how to leave. People may also have trouble with visual images or spatial perception. Noticeable changes in physical mobility - your gait (or how you walk), the length of your stride and how fast you walk - might also be a tip-off to cognitive decline.
"And we've also seen links to falls," Snyder says. "But again, it's very dependent on the individual."
Change in mood, personality
Significant changes in mood might also indicate cognitive decline. Symptoms such as apathy, irritability and agitation, which are similar to those of depression and other psychiatric disorders, may signal dementia's onset if they are pervasive and out of character, Petersen says. Another telltale sign is withdrawal from family or social life.
"If you're sitting around at a dinner table and everyone is talking about things, and you're actually having a difficult time following the conversation and remembering the flow of the conversation, you're maybe more likely to not participate," Snyder says.
Of course, it's possible that other health problems could be causing symptoms that are also associated with Alzheimer's. Conditions such as hyperthyroidism, hormonal imbalances, interactions between medications - even poor nutrition or Lyme disease - can mimic signs of cognitive decline. And many of those conditions are easily reversible.
"That's why it's so important to talk to a health-care provider if you're noticing those sorts of changes in yourself or a loved one," Snyder says.
All three experts agree that the common denominator is change - significant differences from one's lifelong habits of mind and behavior. But it's also important to keep things in perspective.
"The hard message, on the one hand, is be more attentive and be more aware of these, but don't go overboard, and don't obsess," Petersen says. "You have kids in their 20s who forget things. They laugh it off and you laugh. Somehow when you do that in your 60s and 70s, you can't laugh it off. Maybe some of it we should."