Amyloid accumulation in the brain precedes the onset of dementia symptoms. The combined results of blood folate levels and blood cell hemoglobin determined through a blood test may be an accurate measure of amyloid deposits in the brain.
A protein known as apolipoprotein E (APOE) is associated with some forms of Alzheimer’s disease (AD), and has been used as a diagnostic indicator of AD. However, as many as 40% of people who develop AD will not show the presence of APOE.
Amyloid, another type of protein, begins to accumulate in the brain more than a decade before the development of dementia symptoms. As amyloid builds up, it leads to a decrease in the amount of folate (a B vitamin) carried in the blood.
Takuma Yoshinaga and colleagues investigated the relationship between blood folate levels and amyloid imaging studies to see if folate could be used as a better indicator for AD than APOE. In addition, there have been reports that suggest that there is a relationship between mild cognitive impairment (MCI) and the amount of hemoglobin in the blood. Yoshinaga and the other researchers also investigated whether including a measure of the red blood hemoglobin content improved the accuracy of the results. Their study is published in PLoS ONE.
A total of 17 patients, all diagnosed with dementia, underwent brain imaging to measure amyloid deposits and blood tests for folate, hemoglobin and APOE. The average age was approximately 77 years old.
The test results showed that almost 90% of patients with brain amyloid accumulation were found to be folate deficient. When the combination of folate levels, hemoglobin content and APOE were all considered, every case was positive for Alzheimer’s disease. The researchers reached the conclusion that the combination of blood folate and hemoglobin levels is a more specific and sensitive test for Alzheimer’s disease than APOE or folate alone.
In conclusion, using blood folate and hemoglobin levels together may be an accurate way to test for amyloid accumulation in the brain and the possibility of Alzheimer’s disease.
Written By: Sean Manning, BA, DC, MC