New test may help predict development of memory problems

Researchers at Mayo Clinic have developed a scoring system to assess whether an individual is at risk for developing memory problems that could lead to dementia— a potentially inexpensive and easy method to identify the need for further testing, study authors said.

While doctors are able to identify biomarkers for cognitive impairment using MRI and PET scans, they are expensive procedures, study author Dr. Ronald C. Petersen, of Mayo Clinic in Rochester, Minn. and a member of the American Academy of Neurology told

“If we can characterize the general population out there as to who is at high, medium, and low risk we then will be able to allocate these more expensive and invasive procedures intelligently,” he said.

According to the Alzheimer’s Association, every 67 seconds someone in the U.S. develops Alzheimer’s. One in three seniors dies with Alzheimer’s or another form of dementia.

Petersen and his team developed a three-stage prediction approach. For the first stage, which can be done at home, the patient goes through his medical records to see if, based on age, gender, family history, and other medical problems he has a high, medium or low risk. Medical problems such as diabetes, high blood pressure  and smoking have been linked with higher risk for developing cognitive impairment.

In the second stage, the patient goes to his doctor’s office for a mental status test, which can be implemented by office staff. There are a variety of these tests and while they are not diagnostic, they give a rough idea of whether something is going on with a person, clinically, Petersen said. At this appointment, the patient should also give an inventory of any psychiatric symptoms, such as depression, anxiety and apathy, all of which have been shown to be predictive of early cognitive problems.

“By these simple office techniques that take a few minutes, we can now refine that earlier [stage one] predictor [to determine] high, medium, or low risk,” Petersen said.

In the third stage, a patient can get a blood test for the APOE gene, which provides instructions for a protein circulating in the blood. The study found that carriers of the APOE 4 variety were at increased risk for dementia.

“Put these three stages together and at the end of the algorithm then we really have the people who are at higher risk,” Petersen said.

Their test is important because at around age 65, primary care physicians may start thinking about assessing cognitive impairment and while the stages could show patients aren’t at risk, it gives a baselines in the patients’ medical records, Petersen noted.

Their research was part of the Mayo Clinic Study of Aging cohort, which has followed more than 3,000 people for over 10 years. For this study, only the 1,449 patients aged 70 to 89 in October 2014, who did not have memory and thinking problems were included. Researchers studied individuals in this age range as they are most likely to develop cognitive impairment symptoms at this time.

Participants were given memory and thinking tests every 15 years for an average of 4.8 years. Over the course of the study, 401 people, or 28 percent, developed mild cognitive impairment. In the next phase of their work, researchers will observe participants as young as 50.

“We have learned that a lot of the biological processes that lead to cognitive impairment later in life probably began 10 to 15 years earlier,” Petersen said. “That’s really the group you want to identify as early as possible if you’re going to intervene before symptoms arrive.”

While lifestyle modifications such as exercise, intellectual exertion and social networking are standard, and effective, interventions, Petersen hopes effective pharmaceutical therapies will be developed. Cholesterol-lowering drugs are used when a patient does not have heart disease, and disease-modifying drugs for Alzheimer’s could work the same way, he said.

The Mayo Clinic team hopes to work with other research groups to increase their data set and see if their model works.

“Then I think it’d be time to actually move to a practical tool that could be applied by primary care physicians,” Petersen said, adding that developing an algorithm for use with electronic medical records would help automate the process.

“With the aging of America, the number of people who will develop cognitive impairment goes up dramatically so we need to address this now,” he said.