Using Informants to Detect Early Memory Loss
Treatment of Alzheimer’s disease begins with early detection of memory loss, well before any serious symptoms are present and there is an impact on independence. In other words, we need to have a reliable, valid way to detect minor changes in memory that exceed the inefficiencies of aging. At the present time we rely on medical screening with a test that is very insensitive to mild decline in memory – the Mini-Mental State Exam. The major problem with this approach is that it misses all but the most obvious changes in memory. Alternatively, we can seek neuropsychological evaluation to thoroughly measure and describe cognitive skills. This approach is much more sensitive but involves greater time and expense.
More simply we can ask the simple question, “How’s your memory?” After all, most medical and psychological evaluation begins with self-report and a good history. Some are very aware of their own changes in memory. The problem here is that we are asking someone who may be very forgetful to remember. In many memory loss clients, the problem is that they forget that they forget. They are not aware of their problem and will be unable to have insight into their deficits. The technical term for this is anosagnosia.
There is a good supplemental source of information that is easy to use and quite reliable and valid. One can ask family members for their appraisal. I am surprised how often spouses are not an integral part of memory assessment. After all memory loss is a family problem – affects not only the forgetful but also those who live with them. The point of assessment is to help those who are or may become caregivers to better understand what they are dealing with – I always involve family in all of my evaluations.
For example, one could give both the client and the spouse a questionnaire like the PRMQ (Prospective and Retrospective Memory Questionnaire). This is a simple set of questions about memory issues like being able to remember appointments, being able to remember to take medications, or being able to remember to do chores. Indeed, informant corroborated memory loss is superior to self-reported memory loss in assessing memory function in Alzheimer’s disease (The clinical utility of informant appraisals on prospective and retrospective memory in patients with Alzheimer’s disease, PloS One, 2014 19, E112210, PMID 25383950).
Informant’s ratings are highly correlated with objective measures of memory and overall cognitive ability. Informant’s ratings have good specificity and sensitivity for memory loss. Finally, informant’s ratings provide incremental value to both objective test scores and demographics. We need to paint a broader and more accurate picture of the range and scope of memory loss if we are to develop and implement better treatments. We have to include the family in all steps of the evaluation process.