Doctors must listen when patients talk of a failing memory

Apr 6 2006

A team at the Aging and Memory Research Center, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, has found that a higher self awareness of memory difficulties may be associated with brain function decline over time, particularly in older adults with a genetic risk for Alzheimer's disease.

The study, one of the first of its kind, offers a greater understanding of how different types and varying degrees of memory complaints may relate to brain function decline.

The discovery could lead to early treatment interventions for people who could develop Alzheimer's disease.

Dr. Linda Ercoli, lead study author and assistant clinical professor at UCLA , says the study is one of the first to show an association between memory complaints and underlying brain function decline and although not every complaint will lead to Alzheimer's disease, it is important to listen when patients talk about their memory concerns.

The UCLA team tested thirty right-handed, cognitively intact, middle-aged and older adults (age range, 50-82 years) with age-associated memory complaints, 14 of whom were carriers of the apolipoprotein E-IV allele, a marker for Alzheimer's disease, recruited for the longitudinal study.

None of the participants had other conditions such as depression and anxiety that can also affect memory.

The volunteers were given a questionnaire at the start of the study to gauge the frequency, seriousness and type of memory complaints and the researchers measured brain function at both the beginning and end of the two-year study using positron emission tomography (PET).

PET scans measure brain activity by revealing the amount of glucose metabolized by the brain as fuel.

The researchers then measured how complaints were related to decline in brain activity over two years.

They found that for all participants, greater complaints of frequent forgetting were associated with a global brain decline over two years, which appears to be part of the normal aging process.

However, according to the researchers the study participants with the Alzheimer's disease genetic risk factor, APOE-4, who reported more frequent use of strategies such as lists and calendars to compensate for memory difficulties, showed a greater brain function decline in the temporal regions of the brain that are involved with memory functions, compared to participants without the genetic risk.

The researchers say the relationship between greater use of memory compensation strategies and declines in brain function in the temporal regions may be indicative of early developments associated with Alzheimer's disease.

Experts in the field say the findings may eventually help to identify which patients may benefit from clinical monitoring and early interventions to prevent or delay the onset of Alzheimer's disease.

The study is published in the April issue of the Archives of General Psychiatry.