Testing for Alzheimer’s Disease

Alzheimer's disease detection by cognitive tests is as good as using medical tests

(RxWiki News) Mild cognitive impairment (MCI) can progress into other forms of dementia, like Alzheimer’s disease. Science is trying to find ways to predict when MCI will get worse.

A recent study followed patients with MCI after testing them for an Alzheimer’s disease protein and giving them cognitive tests.

They found that both types of tests could predict who would progress from MCI to Alzheimer’s dementia.

"Talk to your doctor about any changes in memory."

The study, led by Sebastian Palmqvist, MD, with Oskar Hansson, MD, PhD, of the Department of Clinical Sciences, Lund University, Malmö, Sweden, followed 133 patients with MCI until they developed dementia or for six years, whichever came first.

At the start of the study, patients in the study did cognitive tests, including the Mini Mental State Examination. The cognitive tests were standard tests that are often used by doctors.

The patients also had a medical test for tau proteins, which are proteins that are known to disrupt brain cell function in Alzheimer’s disease.  Higher levels of tau are thought to predict early Alzheimer’s disease.

Of the people they tracked, 53 percent developed dementia. Alzheimer’s disease was the most common type of dementia in this group of people.

They found that 81 percent of the people who were classified as having early Alzheimer’s disease by the cognitive tests later developed Alzheimer’s disease. The tau protein test classified 83 percent of the cases of Alzheimer’s disease correctly.

Both tests taken together were even more accurate at predicting progression from MCI to Alzheimer’s disease.

The authors concluded that cognitive tests are as accurate as medical tests for tau proteins in predicting progression from MCI to Alzheimer’s disease. The combination of tests added some benefit.

However, the medical tests are more time consuming and costly. The cognitive tests used in this study are brief and can be administered in many different medical settings while being just as effective at predicting Alzheimer’s disease.

This study was published June 22 in PLoS One. One of the co-authors reports serving on an advisory committee for Innogenetics, Belgium. No other conflicts of interest were disclosed.

Review Date: 
July 9, 2012