Table 1.
Baseline demographics and other clinical characteristics by latent class (mean ± SD unless otherwise specified)
| Class 1 n = 162 | Class 2 n = 211 | Class 3 n = 819 | Total n = 1,192 | p-value* | |
| Age (years) | 74.7 ± 8.31 | 74.4 ± 7.28 | 72.9 ± 7.16 | 73.4 ± 7.38 | 0.0021 |
| Female (%) | 59.3% | 62.1% | 54.8% | 56.7% | 0.1287 |
| Race (% Caucasian) | 97.5% | 96.2% | 92.3% | 93.7% | 0.0612 |
| Education (years) | 15.7 ± 2.92 | 15.8 ± 2.92 | 16.1 ± 2.75 | 16.0 ± 2.81 | 0.0968 |
| EVIQ | 114.3 ± 8.83 | 113.7 ± 9.62 | 117.8 ± 8.24 | 116.6 ± 8.75 | <0.0001 |
| Amyloid Positive† | 92.0% | 84.4% | 48.2% | 60.6% | <0.0001 |
| APOE ɛ4 carrier | 69.1% | 64.0% | 38.3% | 47.1% | <0.0001 |
| Diagnosis (%): | <0.0001 (By column) | ||||
| HC (n) | 0 | 2 | 323 | 325 | |
| % of Column | 0.0% | 0.9% | 39.4% | 27.3% | |
| % of Row | 0.0% | 0.6% | 99.4% | 100% | |
| EMCI (n) | 5 | 29 | 245 | 279 | |
| % of Column | 3.1% | 13.7% | 29.9% | 23.4% | |
| % of Row | 1.8% | 10.4% | 87.8% | 100% | |
| LMCI (n) | 29 | 105 | 238 | 372 | |
| % of Column | 17.9% | 49.8% | 29.1% | 31.2% | |
| % of Row | 7.8% | 28.2% | 64.0% | 100% | |
| AD (n) | 128 | 75 | 13 | 216 | |
| % of Column | 79.0% | 35.5% | 1.6% | 18.1% | |
| % of Row | 59.3% | 34.7% | 6.0% | 100% | |
| Medical History | |||||
| Alcohol Abuse | 8.0% | 3.3% | 3.9% | 4.4% | 0.0474 |
| Smoking | 40.1% | 37.4% | 38.7% | 38.7% | 0.8699 |
| Cardiovascular disease | 71% | 64% | 67.9% | 67.6% | 0.3433 |
| Endocrine disease | 42.6% | 42.7% | 40.2% | 40.9% | 0.7261 |
| ADAS-Cog13 | 29.8 ± 9.55 | 23.5 ± 7.39 | 12.5 ± 6.10 | 16.8 ± 9.54 | <0.0001 |
| FAQ | 16.1 ± 6.15 | 6.5 ± 4.41 | 1.2 ± 2.26 | 4.1 ± 6.21 | <0.0001 |
| Animal Category Fluency | 12.0 ± 4.95 | 15.0 ± 5.10 | 19.0 ± 5.33 | 17.4 ± 5.85 | <0.0001 |
| CDR-SB | 4.9 ± 2.08 | 2.6 ± 1.25 | 0.8 ± 0.85 | 1.7 ± 1.86 | <0.0001 |
| Wechsler LM II | 1.7 ± 2.32 | 3.3 ± 3.30 | 9.2 ± 4.65 | 7.1 ± 5.20 | <0.0001 |
| MMSE | 23.5 ± 3.11 | 25.8 ± 2.44 | 28.3 ± 1.73 | 27.2 ± 2.74 | <0.0001 |
| MoCA | 17.3 ± 4.73 | 20.3 ± 3.32 | 24.5 ± 2.89 | 23.1 ± 4.08 | <0.0001 |
| Trail Making Test Part A | 68.7 ± 35.91 | 48.8 ± 26.62 | 36.7 ± 14.40 | 43.1 ± 23.70 | <0.0001 |
| Trail Making Test Part B | 200.8 ± 84.99 | 160.7 ± 80.08 | 96.3 ± 52.76 | 120.9 ± 74.00 | <0.0001 |
| NPI-Q | 4.4 ± 4.62 | 2.9 ± 3.50 | 1.2 ± 1.99 | 2.0 ± 3.07 | <0.0001 |
| GDS Short Form | 1.8 ± 1.76 | 1.7 ± 1.40 | 1.4 ± 1.47 | 1.5 ± 1.51 | 0.0007 |
Data are presented as mean ± SD unless indicated otherwise. APOE, apolipoprotein E; AD, Alzheimer’s disease; ADAS-Cog13, Alzheimer’s Disease Assessment Scale-Cognitive Subscale, 13-item version; CDR-SB, Clinical Dementia Rating Sum of Boxes; EMCI, early mild cognitive impairment; EVIQ, Estimated Verbal Intelligence Quotient; FAQ, Functional Activities Questionnaire; GDS, Geriatric Depression Scale; HC, healthy controls; LM, Logical Memory; LMCI, late mild cognitive impairment; MMSE, Mini-Mental State Examination; MoCA, Montreal Cognitive Assessment; NPI-Q, Neuropsychiatric Inventory-Questionnaire. *p-values were from likelihood ratio test in multinomial logit model for categorical measures and from analysis of variance corrected for uncertainty for continuous variables. Uncertainty in latent class assignment is taken into consideration, using a three-step manual calculation as in Asparouhov & Muthén [15]. †31 cases had discrepant amyloid test results (20 out of 31 discrepant cases were CSF positive but FBP-PET negative).