In the United States, one in eight older adults has Alzheimer’s disease, according to the Alzheimer’s Association. Alzheimer’s disease is a type of dementia, a degenerative neurological condition that affects cognition and behavior.

About 60 to 80 percent of all dementia cases are Alzheimer’s disease cases, noted the Alzheimer’s Association.

Patients with Alzheimer’s disease experience changes to their brain. One of these changes is beta amyloid plaques.

Pieces of the protein beta amyloid build up into plaques, which may affect signaling at the cell synapses and trigger inflammation. These changes to the brain occur before the patient begins to display symptoms.

Identifying the presence of these beta amyloid plaques in the brain might be an important factor when figuring out if an individual is at risk for developing cognitive problems, according to a new study conducted in Australia.

The study included 141 participants whose average age was 76. All participants had no memory or thinking issues before starting the study. The researchers tested all participants for the APOE gene.

The apolipoprotein E, or APOE, has been linked to late-onset Alzheimer’s disease, a “type” of Alzheimer’s disease that develops after age 60. The National Institute on Aging noted that APOE E4 may increase the risk of developing Alzheimer’s disease, but having the gene does not mean the individual will automatically develop the condition.

In addition to being tested for APOE, participants underwent PET scans and computer-based cognitive assessments. Their cognition was assessed and track for a year and a half.

The researchers found that the presence of more beta amyloid plaques was connected to cognitive performance.

A press release from the American Academy of Neurology reported that participants who had more plaques at the beginning of the study had as much as a 20 percent larger decline on the cognitive assessments compared to participants who had fewer plaques.

A greater decline in cognitive performance was also found in individuals who had APOE E4 compared to those who did not. However “carrying the ɛ4 allele did not change the decline in memory related to the plaques,” according to the press release.

This finding may be helpful in diagnosing individuals early before they start showing signs of cognitive impairment.

References

MedlinePlus Medical Encyclopedia. Dementia. Web. 17 October 2012
http://www.nlm.nih.gov/medlineplus/ency/article/000739.htm

Alzheimer’s Association. Types of Dementia. Web. 17 October 2012
http://www.alz.org/dementia/types-of-dementia.asp

Alzheimer’s Association. Alzheimer’s Facts and Figures. Web. 17 October 2012
http://www.alz.org/alzheimers_disease_facts_and_figures.asp

Alzheimer’s Association. More About Plaques. Web. 17 October 2012
http://www.alz.org/braintour/plaques.asp

National Institute on Aging. Alzheimer’s Disease Fact Sheet. Web. 17 October 2012
http://www.nia.nih.gov/alzheimers/publication/alzheimers-disease-fact-sheet

American Academy of Neurology. Plaque Build-up in Your Brain May Be More Harmful than Having Alzheimer’s Gene. Web. 17 October 2012
http://www.aan.com/press/index.cfm?fuseaction=release.view&release=1109

Reviewed October 17, 2012
by Michele Blacksberg RN
Edited by Jody Smith