Cerebrospinal Fluid Test Predicts Alzheimer's Disease

Three biomarkers in cerebrospinal fluid could be used to determine whether or not a clinically healthy person might suffer mild cognitive impairment or Alzheimer's disease, a major form of dementia, according to a new study published in the Aug 2010 issue of Archives of Neurology. 

Geert De Meyer, Ph.D., of Ghent University in Ghent, Belgium and colleagues tested specimens of cerebrospinal fluid collected from 114 older adults who were cognitively normal, 200 who suffered mild cognitive impairment and 102 who were diagnosed with Alzheimer's disease for the three biomarkers, CSF Aß1-42, total CSF tau protein and P-Tau181P. 

A profile or signature of the three biomarkers was found in 90 percent of those with Alzheimer's disease, in 72 percent of those with mild cognitive impairment and in 36 percent of those who had normal, cognitive functions. 

The model was tested in two other data sets to validate its prediction. In one study of 68 patients with autopsy-confirmed Alzheimer's disease, the sensitivity was 94 percent. In another study of 57 patients with mild cognitive impairment, the sensitivity was 100 percent among those whose condition progressed to develop Alzheimer's disease. 

The results suggest that the test may help predict if a person without Alzheimer's symptoms will either develop the disease or some other mild cognitive impairment.  

The problem is that normal individuals may also have the Alzheimer's profile. This means that if you are destined to suffer Alzheimer's, you are expected to have the Alzheimer's signature; however, just because you have the profile does not mean you will definitively develop the disease. 

Alzheimer's, which is increasingly a hot topic among aging baby boomers, affects an estimated 4 million American elderly people. Those aged 65 or older are at higher risk of the disease, for which there is no cure. 

Some researchers, according to media reports, state that the reason no cure can be developed currently is because a diagnosis of Alzheimer's disease is only possible after symptoms show up. But when symptoms manifest themselves, there is no current treatment that could help. 

The researchers of the study hope that at some point, early diagnosis could lead to early treatment, which could be effective in mitigating symptoms, even though no one knows for sure if a cure would be forthcoming. 

The new test on the cerebrospinal fluid itself is not a routine performance, according to  A. Zara Herskovits, M.D., Ph.D., of Brigham and Women's Hospital, and John H. Growdon, M.D., of Massachusetts General Hospital in Boston, who responded to the study in an accompanying editorial. The procedure requires a Spinal Tap. 

They said that in the future, cerebrospinal fluid analyses may be recommended as a screening test to identify clinically healthy (no symptoms) people at risk for mild cognitive impairment and Alzheimer's disease. 

Media reports say the study was funded by the Alzheimer's Disease Neuroimaging Initiative. 

It still remains to be seen if people would accept the screening, as cerebrospinal fluid analyses include a procedure which is not routine. 

Alzheimer's disease is not a health condition resulting from a healthy aging process, according to the National Institutes of Health.  Specifically, Alzheimer's disease is believed to be preventable by controlling adjustable risk factors.  Unfortunately, it is largely unknown what causes the disease. 

Still, suffice it to say that a person's diet, among other things, may play a significant role in the pathology of Alzheimer's disease. 

One study published in June 2010 in the Archives of Neurology suggests that a diet with high amounts of salad dressing, nuts, fish, tomatoes, poultry, cruciferous vegetable, fruits, and dark and leafy green vegetables can reduce the risk while high intake of high fat dairy products, red meat, organ meat and butter increases the risk. 

Gu Y. and colleagues from the Taub Institute for Research for Alzheimer's Disease and the Aging Brain in Columbia University came to the conclusion after analyzing data collected during a 3.9-year follow-up of 2148 community-based elderly people aged 65 or older who did not have dementia upon entering the study.  Participants provided dietary information and the same standardized neurological and neuropsychological measurements were performed every 1.5 years. 

Food Consumer has previously reported extensively on studies intended to elucidate how diet and lifestyle affect the risk of Alzheimer's disease. 

What may help prevent Alzheimer's disease as well as other forms of dementia include green tea, curry, calorie restriction, grape seed extract, red wine, the so called Mediterranean diet, apple juice, high serum vitamin E, physical activity, omega-3 fatty acids, eating garlic, and a plant-based diet. 

Known factors of Alzheimer's disease include obesity, high blood pressure, vitamin D deficiency, depression, a fatty diet, concussions, high blood sugar, and potassium alum or potassium aluminum sulfate, both of which are contained in some popular natural deodorants.

By David Liu and editing by Rachel Stockton