Scientists Develop Simple Memory Test To Predict Cognitive Impairment Years Before Symptoms Appear

Early detection of memory loss and cognitive decline is crucial in the treatment of conditions such as Alzheimer's and dementia. Scientists have now developed a simple memory test that could predict cognitive impairment in people years before the symptoms appear.

More than 16 million people in the United States live with cognitive impairment, wherein they have difficulty remembering, learning new things, concentrating or making decisions that affect their everyday life.

"There is increasing evidence that some people with no thinking and memory problems may actually have very subtle signs of early cognitive impairment. In our study, a sensitive and simple memory test predicted the risk of developing cognitive impairment in people who were otherwise considered to have normal cognition," Ellen Grober, a study author and clinical professor at the Albert Einstein College of Medicine in New York City, said in a news release.

The researchers gave a simple memory test involving cards to 969 people with an average age of 69 who has no thinking or memory problems at the beginning of the study. They were then followed up for up to 10 years.

The memory test had two phases. In the first phase, the researchers asked the participants to look at four cards, each with drawings of four items. The participants were asked to identify each item belonging to a particular category, say when asked to identify fruit, they need to write grapes. The next phase involves recalling the items to measure the ability to retrieve information. When the participants forget certain items, they are given category cues to measure memory storage.

Based on their scores, the participants were divided into five groups, or stages zero through four, as part of the Stages of Objective Memory Impairment (SOMI) system.

A total of 47% of the participants were in stage zero, which represents people with no memory problems, while 35% were in stage one and 13% were in stage two. Stages one and two indicated increasing difficulty to retrieve memories, which researchers said could precede dementia by 5 to 8 years. However, those participants could remember items when given cues.

In the third and fourth stages, people could not recollect all the items even after they were given cues. These stages preceded dementia by one to three years. Around 5% of participants were in these two stages.

At the end of the study, 234 people developed cognitive impairment.

After adjusting for biomarkers of Alzheimer's disease, the researchers found that people at stages one and two were twice as likely to develop cognitive impairment, and people at stages three and four were three times more likely to develop cognitive impairment when compared to stage zero.

The findings also suggested that after 10 years, about 72% of people in the third and fourth stages, 57% of those in the second stage, 35% in the first stage and 21% of those in stage zero would have developed cognitive impairment.

"Our results support the use of the SOMI system to identify people most likely to develop cognitive impairment.Detecting cognitive impairment at its earliest stages is beneficial to researchers investigating treatments. It also could benefit those people who are found to be at increased risk by consulting with their physician and implementing interventions to promote healthy brain aging," Grober added.

The study was published in the medical online journal Neurology. It has certain limitations as most of the participants were white and well-educated. Researchers believe a much larger study involving a diverse population is required.