Table 2a. Concentration of the different AD biomarkers and of N-truncated Aβ peptides in controls (CTRL) and patients with MCI or AD, and their significance in differentiating the three study groups.
| Mean (pg ml−1)±s.d. (min–max) | P-value | |||||
|---|---|---|---|---|---|---|
| |
CTRL (n=21) |
MCI (n=23) |
AD (n=23) |
CTRL vs MCI |
CTRL vs AD |
MCI vs AD |
| Aβ1-42 | 557.48±88.45 (380.21–699.62) | 468.20±152.09 (179.41–829.88) | 356.20±107.48 (186.35–588.39) | <0.05 | <0.001 | <0.01 |
| T-Tau | 54.72±20.13 (22.75–100.22) | 79.51±37.90 (29.95–174.34) | 145.40±89.10 (34.29–398.56) | <0.05 | <0.001 | <0.01 |
| P-Tau | 27.61±7.21 (15.27–41.10) | 36.85±16.99 (12.59–78.16) | 56.37±35.65 (13.75–171.99) | <0.05 | <0.001 | <0.05 |
| Aβ11-40 | 163.56±39.35 (95.75–230.23) | 133.10±28.76 (85.34–192.69) | 133.69±56.77 (30.77–235.95) | <0.01 | 0.051 | 0.97 |
| Aβ11-42 | 26.63±7.14 (15.67–40.99) | 22.23±7.01 (13.81–43.87) | 23.70±11.30 (5.02–50.02) | <0.01 | 0.32 | 0.60 |
| Aβ17-40 | 43.34±28.36 (9.65–98.65) | 45.58±25.49 (8.81–100.02) | 33.93±20.04 (5.19–66.03) | 0.79 | 0.20 | 0.09 |
| Aβ17-42 | 11.63±3.82 (5.58–18.80) | 11.51±7.12 (3.92–27.34) | 8.15±3.60 (1.35–15.25) | 0.94 | <0.05 | 0.051 |
Abbreviations: AD, Alzheimer's disease; CTRL, controls; MCI, mild cognitive impairment; P-Tau, phosphorylated Tau; T-Tau, total Tau.
The CSF biomarkers presented classical AD-like profiles with significant progressive decrease of Aβ1-42 and increase of both T-Tau and P-Tau concentration in accordance with the severity of the pathology. The concentration of the Aβ11-40 and Aβ11-42 peptides was lower in patients with MCI than in controls. Aβ17-40 level did not differ significantly in the three groups and Aβ17-42 concentration was lower in the AD group.