Table 1.
Demographics and Sample Characteristics
| CN (n=58) |
MCI (n=396) |
AD (n=112) |
|
|---|---|---|---|
| Age (years) | 75.1 ± 5.77 | 74.7 ± 7.40 | 74.80 ± 8.08 |
| Gender (% Male) | 51.7 | 64.6 | 58 |
| Education (years) | 15.7 ± 2.78 | 15.6 ± 3.03 | 15.09 ± 3.20 |
| BMI | 26.89 ± 3.84 | 26.01 ± 3.84 | 25.54 ± 3.84 |
| APOE4 (% carriers) | 8.6a | 53.3b | 67.8c |
| Trytophan (μM) | 71.6 ± 13.4a | 71.8 ± 16.00b | 72.55 ± 14.66b |
| Kyn (μM) | 3.33 ± 0.94a | 3.15 ± 1.01a | 3.31 ± 1.11a |
| 5-HT (μM) | 0.675 ± 0.37a | 0.535 ± 0.340b | 0.445 ± 0.407b |
| Kyn/5-HT | 9.19 ± 12.60a | 13.1 ± 18.8b | 23.4 ± 29.4c |
| Kyn/Tryptophan | 0.048 ± 0.015a | 0.045 ± 0.016a | 0.047 ± 0.019a |
| CDR-sob | 0.026 ± 0.11a | 1.60 ± 0.877b | 4.32 ± 1.56c |
| MMSE | 28.9 ± 1.15a | 27.0 ± 1.78b | 23.6 ± 1.91c |
| ADAS-cog11 | 6.25 ± 2.79a | 11.5 ± 4.42b | 18.3 ± 6.42c |
| ADNI Memory Factor | 0.87 ± 0.46a | −0.086 ± 0.586b | −0.814 ± 0.547c |
| ADNI EF Factor | 0.71 ± 0.58a | −0.043 ± 0.783b | −0.934 ± 0.816c |
| GDS Total | 0.86 ± 1.23a | 1.58 ± 1.37b | 1.72 ± 1.36b |
| FAQ Total | 0.05 ± 0.22a | 3.82 ± 4.46b | 12.54 ± 6.71c |
| NPI-Q Total | 0.28 ± 0.72a | 1.85 ± 2.67b | 3.39 ± 3.31c |
| Aβ1–42 (pg/mL) | 251 ± 21.1a | 168 ± 55.6b | 144 ± 40.8c |
| Total Tau (pg/mL) | 63.6 ± 21.8a | 97.4 ± 58.1b | 119 ± 56.8c |
| P-Tau (pg/mL) | 21.1 ± 8.43a | 35.5 ± 18.8b | 41.8 ± 19.7c |
Numbers represent frequency or unadjusted mean ± SD. Superscript letters indicate if a given value for a clinical group is significantly different from other clinical groups. For example, CDR-sob differs between each clinical group, while 5-HT only differs between the CN versus MCI and AD groups. Aβ = beta-amyloid; AD = Alzheimer’s disease; ADAS-Cog = Alzheimer’s Disease Assessment Scale-cognition 11; APOE4 = apolipoprotein E4; BMI = Body Mass Index; CDR-sob=Clinical Dementia Rating – sum of boxes; CN = Cognitively normal; EF = executive function; GDS = Geriatric Depression Scale; FAQ=Functional Assessment Questionnaire; Kyn = Kynurenine; MCI = Mild Cognitive Impairment; MMSE = Mini-Mental State Exam; NPI-Q=Neuropsychiatric Inventory Questionnaire.