The efficacy of plasma biomarkers in early diagnosis of Alzheimer's disease

Abstract

Early diagnosis of Alzheimer's disease (AD) is imperative for the prevention of disease progression and the development of effective treatments. Clinically, AD diagnosis has been based on adherence to clinical criteria. It has recently been proposed that diagnostic criteria should also incorporate biomarker findings. However, the most studied candidates or group of candidates for AD biomarkers, including pathological processes and proteins, needs further research. The current study aimed to investigate the capabilities of the following plasma proteins in the diagnosis of AD and amnesia mild cognitive impairment (aMCI): peripheral interleukin (IL) 10, IL-6, amyloid-β (Aβ) 40, Aβ42, phosphorylated tau 181, and total tau. In addition to 122 normal control (NC) group, 97 AD patients and 54 aMCI patients were recruited for this study. An enzyme-linked immunosorbent assay was used to analyze the concentration of the following blood plasma biomarkers: IL-10, IL-6, Aβ40, Aβ42, phosphorylated tau 181, and total tau. A one-way analysis of variance (one-factor analysis of variance) of Aβ40 and IL-10 levels revealed a statistically significant difference between the three groups (p < 0.001 and p = 0.020). Using Aβ40 ≥ 42.70 pg/ml as the cut-off point, the sensitivity of the ability of Aβ40 to discriminate between AD and NC groups was 80.0%, and specificity was 69.6%. The plasma Aβ40 biomarker was able to distinguish between AD and NC groups. However, the plasma biomarkers in the present research were not able to distinguish between aMCI and NC groups.