TABLE 1.
Cohort characteristics
| Cohort 1 | Cohort 2 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
Control n = 40 |
AD n = 40 | FTD n = 40 | DLB n = 40 | Total n = 160 |
Control n = 38 |
AD n = 38 | FTD n = 38 | DLB n = 38 | Total n = 152 | |
| Age | 56 (53–59) | 58 (55–59) | 64 (61–70) a , b | 70 (62–74) a , b | 59 (56–66) | 63 (59–66) | 63 (59–67) | 63 (59–67) | 67 (64–69) | 64 (60–68) |
| Female sex (%) | 20 (50%) | 20 (50%) | 22 (55%) | 12 (30%) | 74 (46%) | 20 (53%) | 20 (53%) | 20 (53%) | 3 (8%) a , b | 63 (41%) |
| Education | 5 (4–6) | 5 (4–6) | 5 (4–6) | 5 (4–6) | 5 (4–6) | 6 (5–6) | 5 (5–6) | 5 (4–6) | 5 (4–6) | 5 (4–6) |
| MMSE | 28 (25–29) b | 18 (13–22) a | 25 (20–27) a , b | 23 (17–26) a , b | 23 (18–27) | 29 (28–29) b | 20 (18–23) a | 24 (18–27) a | 23 (21–26) a , b | 24 (20–28) |
| CSF Aβ1‐42 (pg/mL)* | 1075 (962–1182) b | 576 (495–652) a | 950 (739–1159) b | 724 (615–991) a , b | 818 (616–1094) | 1092 (922–1271) b | 602 (512–692) a | 942 (761–1270) b | 839 (648–1094) a , b | 856 (648–1120) |
| CSF amyloid positive (%) | 0 (0%) | 40 (100%) | 10 (25%) | 24 (60%) | 74 (46%) | 0 (0%) | 38 (100%) | 10 (29%) | 18 (47%) | 66 (45%) |
| Mass spectrometry | ||||||||||
| Aβ1‐42/1‐40 ratio* | 0.044 (0.042–0.048) b | 0.037 (0.035–0.041) a | 0.041 (0.038–0.045) | 0.043 (0.038–0.044) b | 0.042 (0.037–0.045) | N.A. | N.A. | N.A. | N.A. | N.A. |
| Aβ1‐42 (pg/mL)* | 0.49 (0.42–0.53) b | 0.41 (0.36–0.45) a | 0.46 (0.42–0.52) b | 0.48 (0.44–0.56) b | 0.46 (0.42–0.52) b | N.A. | N.A. | N.A. | N.A. | N.A. |
| Aβ1‐40 (pg/mL)* | 10.8 (9.8–11.8) | 10.5 (9.5–12.1) | 11.5 (10.3–12.5) | 11.7 (10.4–13.1) | 11.1 (9.9–12.5) | N.A. | N.A. | N.A. | N.A. | N.A. |
| APP699‐711 (pg/mL)* | 0.46 (0.40–0.50) | 0.40 (0.37–0.50) | 0.42 (0.36–0.48) | 0.45 (0.38–0.53) | 0.43 (0.38–0.48) | N.A. | N.A. | N.A. | N.A. | N.A. |
| Simoa | ||||||||||
| Aβ1‐42/1‐40 ratio* | 0.14 (0.13–0.16) b | 0.12 (0.11–0.13) a | 0.13 (0.11–0.14) a | 0.13 (0.11–0.14) a | 0.13 (0.12–0.14) | 0.06 (0.05–0.07) b | 0.05 (0.05–0.06) a | 0.05 (0.05–0.06) | 0.05 (0.05–0.06) | 0.05 (0.05–0.06) |
| Aβ1‐42 (pg/mL)* | 12.7 (11.1–14.5) b | 10.9 (9.0–11.7) a | 11.6 (9.7–13.1) | 11.3 (10.6–13.1) | 11.5 (9.9–13.1) | 7.22 (6.48–7.73) b | 6.16 (5.47–6.73) a | 7.33 (6.47–8.34) b | 6.83 (6.25–8.20) b | 6.81 (6.10–7.74) |
| Aβ1‐40 (pg/mL)* | 88.4 (82.9–97.0) | 90.7 (78.0–97.3) | 93.3 (83.4–103.6) | 90.5 (85.5–102.9) | 90.4 (82.6–100.5) | 115 (105–137) | 119 (102–140) | 136 (117–154) a , b | 125 (114–147) | 124 (109–145) |
| NfL (pg/mL)* | 17.0 (13.4–23.6) a , b | 31.3 (25.2–40.1) a | 45.5 (35.3–86.5) a , b | 30.9 (22.1–53.3) a | 30.6 (20.8–44.6) | 11.0 (8.5–15.3) b | 18.8 (14.0–25.7) a | 28.7 (21.4–52.0) a , b | 15.5 (11.7–20.2) | 17.6 (12.0–26.8) |
| GFAP (pg/mL)* | 534 (342–693) b | 1580 (1091–1970) a | 943 (610–1231) a , b | 1047 (611–1580) a , b | 962 (563–1487) | 66.6 (47.1–85.9) b | 119 (99.4–178) a | 91.0 (54.2–128) b | 106 (65.6–142) a , b | 96.4 (59.0–129) |
| P‐tau181 (pg/mL), plasma | 1.18 (0.92–1.39) b | 2.94 (2.04–3.99) a | 1.35 (0.94–2.05) b | 1.81 (1.09–2.65) a , b | 1.61 (1.03–2.59) | 1.24 (1.09–1.64) b | 2.60 (2.01–3.03) a | 1.65 (1.09–2.71) b | 1.55 (1.07–2.04) b | 1.68 (1.20–2.55) |
Notes: Values shown as median (interquartile range). Aβ1‐42, Aβ1‐40, NfL, and GFAP were measured with the 4‐plex pre‐commercial assay in cohort 1, and with the 4‐plex commercial assay in cohort 2. These two assays give different absolute values. CSF Aβ1‐42 was missing for 4 FTD patients of cohort 2.
Abbreviations: Aβ, amyloid beta; AD, Alzheimer's disease; CSF, cerebrospinal fluid; DLB, dementia with Lewy bodies; FTD, frontotemporal dementia; GFAP, glial fibrillary acidic protein; NfL, neurofilament light; p‐tau181, phosphorylated tau 181.
a
Indicates a statistically significant difference between groups (P < .05) with Control in post hoc pairwise comparisons.
b
P < .05 versus AD.