Genetic tests for Alzheimer’s disease a comfort for the majority

Genetic testing for Alzheimer’s disease can reduce anxiety for people, regardless of whether the test confirms a risk of developing the disease.

Several genetic tests are available for Alzheimer’s disease, both for the general public and for those with a family history of the disease. As direct-to-consumer testing over the internet rises, so have concerns over how people will handle information related to their risk of developing Alzheimer’s disease.

But a review of over 20 years of psychological research by a team of Australian researchers from Neuroscience Research Australia, UNSW Medicine, Prince of Wales Hospital, University of Sydney, NSW Health and University of Tasmania, shows that the majority of people do not develop adverse psychological effects following testing.

“As genetic testing for Alzheimer’s disease becomes increasingly accessible, a better understanding of the psychological and behavioral effects of those who have had testing can be used to inform and improve testing protocols and procedures,” says study author Prof Peter Schofield from Neuroscience Research Australia.

Genetic testing is especially important for early-onset Alzheimer’s disease, as this is most likely to be inherited from a parent. Alzheimer’s disease is classified as early-onset if symptoms develop around 60–65 years of age, and late-onset when symptoms develop after this age.

“Young adults may be aware that their parents have a mutation and early-onset Alzheimer’s disease but don't see any need for genetic testing until they are ready to have children. But some want to know sooner rather than later and if the test is negative they can move on; if positive, they’ll know what the future holds,” Prof Schofield says.

Late-onset Alzheimer’s disease can also be due to genes, although the risks associated with gene variants for late-onset Alzheimer’s disease are lower than for early-onset Alzheimer’s disease. A few genetic tests exist for late-onset Alzheimer’s disease, however, they are not widely endorsed by the medical community.

“Although testing for late-onset Alzheimer’s disease is not currently recommended due to a lack of preventative strategies and treatments, knowing your genetic risk of Alzheimer’s disease may be of benefit when making health behaviour changes or long-term care insurance decisions. Our review shows that the majority of people experience decreased anxiety and derive other psychological benefits from having greater certainty after genetic testing” Prof Schofield says.

The paper is published (and freely available) in the journal Genetic Testing and Molecular Biomarkers.