Alzheimer’s Disease: Subjective Memory Complaints May Predict Future Cognitive Decline

Dr. Erin Abner Ph.D. Assistant Professor of Epidemiology University of Kentucky College of Public Health Lexington, Interview with:
Dr. Erin Abner Ph.D.
Assistant Professor of Epidemiology
University of Kentucky College of Public Health
Lexington, Kentucky What are the main findings of the study?

Dr. Abner:  The findings from this study are preliminary results from The Prevention of Alzheimer’s Disease with Vitamin E and Selenium Study. This early look at the data indicates that very simple measures of memory change, in this case asking older men with no cognitive impairment about changes in their memory over the past year, and whether they believe those changes are a problem, can be used to predict cognitive impairment years later. Men who said at study baseline that the changes in their memory represented problems to them were over twice as likely as men who did not complain to develop clinically detectable cognitive impairment during follow-up. This is exciting because the field of Alzheimer’s research is moving toward earlier intervention in the disease process. As of now, our best methods for identifying individuals without cognitive impairment who are likely to develop Alzheimer’s disease in the future are procedures that many people find intimidating, like lumbar puncture and PET scanning. Identifying older adults at high risk for future cognitive impairment with low-cost, non-invasive screening techniques would help researchers to target potential therapies to the people who stand to benefit the most. Were any of the findings unexpected?

Dr. Abner: We found that memory complaints that presented problems were particularly important for men who did not carry the apolipoprotein-ε4 allele (an important genetic risk factor for Alzheimer’s disease). Compared to men without the allele who did not complain, these men were over four times as likely to develop cognitive impairment. For men with the allele, complaints only increased the risk by about 50%. What should clinicians and patients take away from your report?

Dr. Abner:  Clinicians should be encouraged to use a longitudinal perspective when they screen patients for memory problems. When research participants first begin to make memory complaints they usually perform no differently on memory tests than participants who do not make complaints. So, when a patient reports a decline in memory, particularly one that they find troubling, they may still make a perfect score on a memory screen. However, the patient is at an increased risk for future cognitive impairment.

Patients, on the other hand, should not be unduly alarmed by lapses in memory. Many people who complain about their memory never develop Alzheimer’s disease. The key is whether there has been a change from previous levels of functioning. If there has, and if the patient is concerned about it, a visit to a neurologist for a memory work-up may be in order. A diagnosis of mild cognitive impairment or early Alzheimer’s disease can be frightening, since we still don’t have effective treatments, but early diagnosis can also be very positive. The early stages of the disease often involve behavioral changes, such as paranoia and irritability, that can strain relationships, particularly when there is no explanation for what’s happening. Early diagnosis also allows patients to make plans for the future and to participate in clinical trials. What recommendations do you have for future research as a result of this study?

Dr. Abner:  Ultimately, maximizing the clinical utility of memory complaints is the goal. We don’t yet have a good understanding of how to differentiate memory complaints that precede cognitive impairments from memory complaints that don’t progress.


Subjective Memory Complaints May Predict Clinical Impairment

Presented at: Clinical Trials Conference on Alzheimer’s Disease
San Diego, CA November 2013