2022 Alzheimer's Association Research Grant (AARG)

Impact on Copathologies in Sporadic Early-Onset Alzheimer’s disease

How might co-occurring dementias impact cognitive and brain changes in early-onset Alzheimer’s?

Renaud La Joie, Ph.D.
University of California, San Francisco
San Francisco, CA - United States

Background

Alzheimer’s disease is associated with specific brain changes including the accumulation of the proteins beta-amyloid and tau into abnormal plaques and tangles, respectively. In addition to beta-amyloid plaques and tau tangles, some individuals with Alzheimer’s exhibit additional biological brain changes that also contribute to cognitive dysfunction and behavior changes; this is referred to as mixed dementia and involves brain changes associated with different brain diseases. According to the 2022 Alzheimer’s and Association Facts and Figures report, recent studies show that more than half of individuals who had Alzheimer's also had brain changes of one or more other causes of dementia, such as Lewy body disease or Frontotemporal dementia.

Currently, there are techniques to detect abnormal beta-amyloid and tau in the brains of living individuals. However, these techniques only provide a partial window on the underlying biological brain changes in the individual. This is because there are no tests of biological markers (biomarkers) to examine brain changes associated with other brain diseases that may accompany Alzheimer’s in the brain. It is currently not possible to evaluate the relative impact of Alzheimer’s brain changes versus other potentially co-occurring brain changes.
 

Research Plan

Dr. Renaud La Joie and colleagues will use brain imaging and cognitive tests to study the unique brain and cognitive changes associated with two co-occurring brain diseases that cause dementia in individuals with early-onset Alzheimer’s (individuals who develop symptoms before the age of 65). 

Dr. La Joie and team will determine how cognitive measures, such as performance on memory tasks, declines over time in these individuals. In addition, the researchers will use brain imaging to study the structure and function of specific brain regions.
 

Impact

The results of this project may shed light on the role of brain changes associated with multiple brain diseases in individuals and potentially identify cognitive or brain imaging biomarkers associated with these co-occurring brain changes. The findings may help identify which individuals may benefit from different therapeutic approaches.