A two-minute memory test can uncover many cases of dementia that otherwise go unnoticed by doctors, according to Minneapolis VA researchers who concluded that the screening "should be considered in all older adults.''

The test, known as the "mini-cog," was given to more than 8,000 older veterans to see if it could work as an early warning sign for Alzheimer's and other memory disorders.

Nearly 11 percent of the patients aged 70 or older were diagnosed with some form of cognitive impairment, compared to 4 percent in clinics that didn't use the test, according to the study by the Minneapolis Veterans Affairs Medical Center.

The results are part of a growing movement to identify cognitive problems early. "I think there's increasing data in the last few years that unrecognized cognitive impairment leads to worse health outcomes," said Dr. Riley McCarten, a neurologist at the Minneapolis VA who led the study.

People with memory problems may have trouble following medical advice or taking their blood pressure pills, he said, and yet their doctors may be in the dark. "Most people with dementia, particularly in the early and even moderate stages, look completely normal," he said. "If you don't test them, you don't know they're impaired."

The mini-cog is one of a number of memory tests that have started to pop up in routine checkups for older patients around the country, including at Allina clinics in Minnesota. In this case, the test involves memorizing three words and drawing the face of a clock.

The idea of routine testing for memory problems has been gaining acceptance, said Maria Carrillo, a senior medical director at the Alzheimer's Association in Chicago. "The field in general has started to move toward the idea of trying to identify Alzheimer's earlier."

She said her organization is part of a national working group trying to identify which tests are most effective. The mini-cog is probably one of the quickest and most popular, but she said there's no consensus on which test is best.

Several years ago, the Minneapolis VA started offering the mini-cog during routine checkups of veterans 70 or older with no known history of memory problems. Nearly everyone (97 percent) agreed to take the test; of those, 26 percent failed, according to the report.

Sooner rather than later

Anyone who failed was offered a more thorough evaluation. Of those who agreed to a follow-up, 75 percent turned out to have dementia, the study found. In fact, even a few people who passed the mini-cog asked for further evaluation and turned out to have dementia as well, McCarten said. In those cases, "people tend to come forward and say, 'You know what, I think I do have a problem.'"

At the same time, McCarten said nearly three-fourths of those who failed the mini-cog refused follow-up. Sometimes it takes several visits -- and several failed tests -- before they're ready for an answer.

"We think of it as a process," he said. "This is foreign to most people. They don't usually get a quiz when they go to the doctor." When it's part of their routine checkups, he said, "they may be more accepting of having further evaluation."

Carrillo, of the Alzheimer's Association, noted that some memory problems are caused by medications or depression and might be reversible. But even if they're not, she said, patients and families can benefit by finding out about the dementia sooner rather than later.

McCarten agrees. "Just because somebody doesn't have a diagnosis doesn't mean you're not dealing with their problems," he said.

Often, it takes a crisis to realize someone is impaired and unable to care for himself. "You make a big impact if you can diagnose this and avert some of those crises," he said.

The study is published in Monday's Journal of the American Geriatrics Society.

Maura Lerner • 612-673-7384