Biomarkers May Predict Incipient Alzheimer's Disease
Levels of amyloid-β42, total tau, and phosphorylated tau linked to disease progression
TUESDAY, July 21 (HealthDay News) -- In patients with mild cognitive impairment, three cerebrospinal fluid biomarkers may accurately identify incipient Alzheimer's disease, according to a study published in the July 22/29 issue of the Journal of the American Medical Association.
Niklas Mattsson, M.D., of Sahlgrenska University Hospital in Molndal, Sweden, and colleagues recruited 750 patients with mild cognitive impairment, 529 patients with Alzheimer's disease, and 304 controls at 12 centers in Europe and the United States, and measured baseline levels of amyloid-β42 (Aβ42), total tau, and phosphorylated tau.
After following the subjects for at least two years or until symptoms had progressed to clinical dementia, the researchers observed that 271 cases of mild cognitive impairment had progressed to Alzheimer's disease. Compared to cases that did not progress to Alzheimer's disease, they found that those who progressed had lower median levels of Aβ42, and higher levels of total tau and phosphorylated tau. They determined that a combination of Aβ42/phosphorylated tau ratio and total tau had a sensitivity and specificity of 83 percent and 72 percent, respectively, in identifying incipient Alzheimer's disease.
"The study by Mattsson et al represents a major step forward in suggesting that biomarkers may have sufficient accuracy to be used in the Alzheimer's disease prodromal phase," state the authors of an accompanying editorial. "The report highlights the challenges but also suggests solutions. Subsequent prospective investigations should clarify the true utility of these measures."
One author of the study and an author of the editorial reported financial relationships with the pharmaceutical industry.