Fig. 3
From: Clinical and biological relevance of glial fibrillary acidic protein in Alzheimer’s disease
Linear fitting between age and blood-based biomarkers across all participants. Significant associations were still observed when blood-based biomarkers were adjusted for CDR score or AV45 composite SUVR. The analysis was carried out without adjusting for demographical variables since age was the factor of interest. Age explained 12%, 5%, and 26% of variance for plasma GFAP, ptau-181, and NfL respectively based on r2 value. The age effects on all three markers were not significantly different between CU − and Amy + (both CU + and CI + included) participants. The shaded area represents the 95% confidence interval of the fitting curve