Clinical Epidemiology and Ageing

Plasma amyloid beta predicts conversion to dementia in subjects with mild cognitive impairment: The BALTAZAR study.

Hanon O, Vidal J-S, Lehmann S, Bombois S, Allinquant B, Baret-Rose C, Tréluyer J-M, Abdoul H, Gelé P, Delmaire C, Blanc F, Mangin J-F, Buée L, Touchon J, Hugon J, Vellas B, Galbrun E, Benetos A, Berrut G, Paillaud E, Wallon D, Castelnovo G, Volpe-Gillot L, Paccalin M, Robert P, Godefroy O, Camus V, Belmin J, Vandel P, Novella J-L, Duron E, Rigaud A-S, Schraen-Maschke S, Gabelle A Alzheimers Dement. 2022;18(12):2537-2550.

INTRODUCTION: Blood-based biomarkers are the next challenge for Alzheimer's disease (AD) diagnosis and prognosis.

METHODS: Mild cognitive impairment (MCI) participants (N = 485) of the BALTAZAR study, a large-scale longitudinal multicenter cohort, were followed-up for 3 years. A total of 165 of them converted to dementia (95% AD). Associations of conversion and plasma amyloid beta (Aβ) , Aβ , Aβ /Aβ ratio were analyzed with logistic and Cox models.

RESULTS: Converters to dementia had lower level of plasma Aβ (37.1 pg/mL [12.5] vs. 39.2 [11.1] , P value = .03) and lower Aβ /Aβ ratio than non-converters (0.148 [0.125] vs. 0.154 [0.076], P value = .02). MCI participants in the highest quartile of Aβ /Aβ ratio (>0.169) had a significant lower risk of conversion (hazard ratio adjusted for age, sex, education, apolipoprotein E ε4, hippocampus atrophy = 0.52 (95% confidence interval [0.31-0.86], P value = .01).

DISCUSSION: In this large cohort of MCI subjects we identified a threshold for plasma Aβ /Aβ ratio that may detect patients with a low risk of conversion to dementia within 3 years.

MeSH terms: Alzheimer Disease; Amyloid beta-Peptides; Apolipoprotein E4; Biomarkers; Cognitive Dysfunction; Disease Progression; Humans; Peptide Fragments; tau Proteins
DOI: 10.1002/alz.12613