New Biomarker May Identify Early Alzheimer's Disease
Soluble amyloid precursor proteinβ superior to Amyloidβ1-42 for identifying AD
THURSDAY, June 23 (HealthDay News) -- Soluble amyloid precursor proteinβ (sAPPβ) may be a useful biomarker for incipient Alzheimer's disease (AD), according to a study published online June 22 in Neurology.
Robert Perneczky, M.D., from Technische Universität München in Germany, and colleagues assessed whether sAPPs in cerebrospinal fluid (CSF) have a role in the identification of patients with incipient AD in a cohort of 58 patients with mild cognitive impairment (MCI). CSF sampling was performed at baseline. During follow-up, 21 patients progressed to probable AD (MCI-AD), 27 had MCI, eight reverted to normal (MCI-no AD [MCI-NAD]), and two patients with frontotemporal dementia (FTD) were excluded. CSF biomarker specificity was assessed using 16 patients with FTD. Enzyme-linked immunosorbent assays were used to determine CSF concentration of sAPPα, sAPPβ, tau, and Amyloidβ1-42 (Aβ1-42).
The investigators found that there were significantly higher sAPPβ concentrations in the MCI-AD group than in the MCI-NAD and FTD groups. The best model for differentiating between MCI-AD and MCI-NAD was a combination of sAPPβ, tau, and age, which had a sensitivity of 80 percent and a specificity of 81 percent. The combination of sAPPβ and tau was best for differentiating MCI-AD and FTD, with a sensitivity and specificity of 95.2 and 81.2 percent, respectively. Neither sAPPα nor Aβ1-42 offered a significant contribution to the models.
"sAPPβ may be clinically useful, and superior to Aβ1-42, in the identification of patients with AD in the MCI stage and in the differentiation of incipient AD from FTD," the authors write.
Several authors disclosed financial ties to the pharmaceutical industry.