Table 1.
Means, standard deviations, proportions and statistical comparison of demographic, clinical and neuropsychological data for participants included in analysis. For continuous characteristics a Wilcoxon rank sum test was used, while categorical characteristics were compared between groups using Fisher's exact test.
| Participant groups |
p-value |
|||||
|---|---|---|---|---|---|---|
| HC (n = 24) | tAD (n = 27) | PCA (n = 12) | tAD vs HC | PCA vs HC | tAD vs PCA | |
| Demographics & clinical | ||||||
| Age – years | 60.1 (5.7) | 61.1 (5.1) | 61.2 (4.8) | 0.72 | 0.79 | 0.93 |
| % female | 54% | 75% | 56% | 0.57 | 0.20 | 0.22 |
| Handedness (Left: Right) | 3:21 | 1:26 | 1:11 | 0.26 | 0.59 | 0.53 |
| TIV (cm3) | 1482 (135) | 1461 (171) | 1480 (146) | 0.65 | 0.97 | 0.61 |
| Symptom duration (years) | n/a | 5.0 (2.8) | 4.6 (2.1) | n/a | n/a | 0.89 |
| Education (years) | 16.7 (3.0) | 15.1 (2.9) | 15 (2.6) | 0.10 | 0.10 | 0.8 |
| MMSE (/30) | 29.5 (0.7) | 19.8 (5.2) | 22.7 (5.1) | <0.0001 | <0.0001 | 0.10 |
| % APOE ε4 carriers | n/a | 67% | 42% | n/a | n/a | 0.17 |
| General intellect | ||||||
| WASI vocabulary (/80) | 68.0 (8.8) | 53.5 (17.4) | 54.8 (19.6) | 0.0009 | 0.0053 | 0.78 |
| WASI matrices (/32) | 26.7 (2.7) | 10.6 (7.8) | 4.5 (4.6)n=11 | <0.0001 | <0.0001 | 0.017a |
| Digit span | ||||||
| forwards (max) | 7.2 (1.2) | 5.6 (1.4) | 5.4 (1.4) | 0.0002 | 0.0009 | 0.77 |
| backwards (max) | 5.5 (1.4) | 3.2 (1.4)n=26 | 2.7 (1.4) | <0.0001 | <0.0001 | 0.32 |
| Episodic memory | ||||||
| RMT faces (/25) | 24.6 (0.9) | 20.2 (4.2) | 18.3 (4.1) | <0.0001 | <0.0001 | 0.16 |
| RMT words (/25) | 24.3 (1.4) | 17.1 (2.9) | 20.5 (4.4) | <0.0001 | 0.0008 | 0.017 |
| Verbal fluency | ||||||
| Letter (F) | 23.3 (5.4) | 10.2 (5.5) | 11.8 (5.6)n=11 | 0.011 | 0.0019 | 0.89 |
| Category (animals) | 15.7 (6.1) | 9.4 (4.9) | 9.6 (2.3)n=11 | <0.0001 | 0.0001 | 0.11 |
| Reading, spelling & arithmetic | ||||||
| NART: total errors (/50) | 37.8 (8.2) | 30.7 (10.8) | 30.6 (11.1)n=10 | 0.012 | 0.049 | 0.93 |
| GDST: oral (/30) | 26.1 (4.3) | 14.8 (9.2)n=26 | 13.5 (.4)n=11 | <0.0001 | 0.0002 | 0.83 |
| GDA: oral (/24) | 14.0 (6.5) | 3.4 (5.4)n=25 | 2.6 (3.5) | <0.0001 | <0.0001 | 0.74 |
| Visual processing | ||||||
| VOSP – shape detection (/20) | 19.4 (0.8)n=23 | 18.5 (1.4)n=26 | 16.9 (2.6)n=11 | 0.0082 | 0.0001 | 0.02 |
| VOSP – object decision (/20) | 18.0 (1.4) | 16.1 (3.1) | 10.8 (3.9) | <0.0001 | <0.0001 | 0.0003 |
| VOSP – fragmented letters (/20) | 19.5 (0.7)n=23 | 13.2 (7.1)n=26 | 7.0 (5.4)n=11 | <0.0001 | <0.0001 | 0.013 |
| VOSP – dot counting (/10) | 9.9 (0.3) | 8.4 (2.7)n=26 | 5.5 (3.3)n=11 | 0.0076 | <0.0001 | 0.0084 |
| A cancellation (time – seconds) | 21.1 (6.0) | 43.0 (21.1) | 69.5 (19.8)n=11 | <0.0001 | <0.0001 | 0.002 |
| A cancellation (total errors) | 0.1 (0.3) | 0.6 (1.4)n=26 | 3 (3.7) n=11 | 0.16 | 0.0008 | 0.019 |
Key: HC = Healthy controls; tAD = amnestic led typical Alzheimer's disease; PCA = posterior cortical atrophy; MMSE = Mini-Mental State Examination; WASI = Wechsler Abbreviated Scale of Intelligence; sRMT = Short Recognition Memory Test; NART = National Adult Reading Test; Graded Difficulty Spelling Test (GDST); GDA = Graded Difficulty Arithmetic; VOSP = Visual Object and Space Perception battery. Where data is only available for a subset of participants, the total n is specified for that variable.