Common neuropsychiatric behaviors in dementia such as apathy and anxiety are most likely spurred by damage to the brain — and are not due to cognitive impairment, a new study finds.
Investigators tested cerebrospinal fluid or blood plasma from 356 older adults without cognitive impairment. They looked for levels of amyloid-beta (Ab) and tau proteins, which are associated with Alzheimer’s disease and are known markers of neurodegeneration.
The results were striking, they said. The presence of amyloid-beta was linked to increased anxiety and apathy. What’s more, the higher the level of apathy the more rapidly study participants experienced cognitive decline, reported Oskar Hansson, M.D., of Lund University in Sweden, and colleagues.
“We are used to thinking about Alzheimer’s disease from the perspective of memory impairments,” he said in a statement. “This new study highlights that the earliest signs of amyloid-related pathology may be changes in mood and behavior, particularly apathy and anxiety.”
Full findings were published in the journal Biological Psychiatry.