Study finds Alzheimer’s markers in patients’ relatives

An amino acid commonly found in the brains of Alzheimer’s patients has been discovered in the spinal fluid of people without dementia whose close relatives were diagnosed with the disease, according to a study led by Duke University researchers.

The researchers also found people closely related to an Alzheimer’s patient were more likely to have a smaller-than-normal hippocampus, the portion of the brain linked to memory. The findings could help lay the groundwork for development of early-detection tools, said Erika Lambert, a Duke researcher involved in the project.

“It’s possible that these changes are among the reasons people with a family history of Alzheimer’s are more likely to get Alzheimer’s,” Lambert said

People with a close family history of Alzheimer’s have a two- to four-times greater risk of developing it themselves.

The study, published this month in the online journal PLOS ONE, involved 257 people ages 55 to 89, all of whom had average memory functions or were considered “mildly forgetful,” said P. Murali Doraiswamy, Duke professor of psychiatry and medicine and senior author of the study.

Researchers found that about 50 percent of healthy people with a close family connection to Alzheimer’s could be considered to have early signs of the disease, compared to about 20 percent of people without a family history.