Table 3.

CSF biomarkers for neurodegenerative diseases

Biomarker	Target	Advantages	Disadvantages
Aβ42	Amyloid-β peptides	Strong correlation with 11C-PiB PET status	Different cutoff values used in different labs
Aβ40	Amyloid-β peptides	Added value when combined with Aβ42	Not a clinically meaningful biomarker in isolation
Aβ42/Aβ40 ratio	Amyloid-β peptides	Stronger diagnostic and prognostic value than Aβ42 alone	Not yet widely implemented
Aβ42/Aβ38 ratio	Amyloid-β peptides	Stronger diagnostic and prognostic value than Aβ42 alone	Not yet widely implemented
t-Tau	Tau peptides	Reasonably sensitive for late-stage AD	Poor specificity, not clinically useful in isolation
p-Thr181 tau	Tau peptides	Reasonably sensitive for late-stage AD	Poor specificity, not clinically useful in isolation
NfL	White matter damage	Indicates the presence of neurodegeneration	Increased in multiple neurodegenerative diseases

Abbreviations: Aβ amyloid-β, NfL neurofilament light chain