Table 2. Baseline and follow-up levels of CSF tau and Aβ42 in the AD patients and age-matched controls.

	Controls, n = 34	1-year AD cohort, n = 100	2-year AD cohort, n = 45
Baseline Tau, ng/L	412±232	693±301a	663±308a
Follow-up Tau, ng/L	399±194	731±402	768±528b
Longitudinal difference, Tau, %	−3.2	+5.5	+15.8
Baseline Aβ42, ng/L	659±179	275±103a	288±103a
Follow-up Aβ42, ng/L	651±168	296±132	321±137
Longitudinal difference, Aβ42, %	−1.2	+7.6	+11.5

Values are means±SD except if noted otherwise.

^ap<0.001 vs Controls.

^bp<0.05 vs baseline.

Abbreviations: CSF, cerebrospinal fluid; 1-year AD cohort, subjects with Alzheimer's disease with an interval between baseline and follow-up lumbar puncture of approximately one year; 2-year AD cohort, subjects with Alzheimer's disease with an interval between baseline and follow-up lumbar puncture of approximately two years. Controls, healthy controls followed for 4 years.