Table 1.
Means (SDs) | ||||||||
---|---|---|---|---|---|---|---|---|
Cognitive domain | All (N = 2066) | No impairment (N = 1965) | MCI | P value | Probable dementia | P value | MCI or probable dementia (N = 101) | P value |
PMA vocabulary | 36.93 (9.580) | 37.24 (9.420) | 31.19 (10.56) | <0.0001 | 31.00 (10.44) | <0.0001 | 30.86 (10.64) | <0.0001 |
Letter fluency | 40.03 (12.35) | 40.18 (12.27) | 37.47 (13.57) | 0.0639 | 37.82 (14.50) | 0.2050 | 37.15 (13.51) | 0.0162 |
Category fluency | 29.15 (6.215) | 29.37 (6.168) | 24.07 (4.922) | <0.0001 | 25.44 (6.298) | <0.0001 | 24.91 (5.589) | <0.0001 |
*BVRT | 6.915 (3.675) | 6.755 (3.579) | 9.838 (4.122) | <0.0001 | 10.36 (4.483) | <0.0001 | 10.01 (4.151) | <0.0001 |
CVLT (learning) | 29.03 (6.174) | 29.34 (6.009) | 23.05 (5.527) | <0.0001 | 22.00 (6.931) | <0.0001 | 23.03 (6.308) | <0.0001 |
CVLT (short-delay free recall) | 8.587 (3.018) | 8.756 (2.925) | 5.365 (2.672) | <0.0001 | 4.822 (3.284) | <0.0001 | 5.287 (2.923) | <0.0001 |
CVLT (long-delay free recall) | 9.334 (2.975) | 9.488 (2.893) | 6.203 (2.669) | <0.0001 | 6.022 (3.583) | <0.0001 | 6.337 (2.984) | <0.0001 |
Digits forward | 7.484 (2.059) | 7.524 (2.066) | 6.608 (1.719) | <0.0001 | 6.978 (1.738) | 0.0789 | 6.713 (1.751) | <0.0001 |
Digits backward | 6.723 (2.022) | 6.765 (2.029) | 6.041 (1.716) | 0.0025 | 5.867 (1.590) | 0.0005 | 5.891 (1.696) | <0.0001 |
Card rotations | 56.38 (26.94) | 57.13 (26.81) | 43.78 (24.26) | <0.0001 | 36.89 (26.25) | <0.0001 | 41.66 (25.30) | <0.0001 |
Finger tapping (dominant) | 38.57 (7.561) | 38.67 (7.566) | 36.64 (7.242) | 0.0237 | 38.00 (6.801) | 0.5583 | 36.71 (7.245) | 0.0113 |
Finger tapping (nondominant) | 36.46 (6.417) | 36.58 (6.419) | 34.11 (6.080) | 0.0012 | 35.32 (5.915) | 0.1931 | 34.14 (5.955) | 0.0002 |
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Standardized total score (z-scores): verbal fluency, CVLT, digits forward and backward, and fine motor speed | ||||||||
Verbal fluency | −0.046 (0.952) | −0.019 (0.945) | −0.633 (0.873) | <0.0001 | −0.490 (1.009) | 0.0010 | −0.570 (0.932) | <0.0001 |
CVLT | 0.024 (0.932) | 0.076 (0.902) | −1.01 (0.813) | <0.0001 | −1.11 (1.104) | <0.0001 | −0.988 (0.926) | <0.0001 |
Digits forward and backward | −0.017 (0.993) | 0.006 (0.997) | −0.446 (0.805) | <0.0001 | −0.396 (0.718) | 0.0006 | −0.460 (0.787) | <0.0001 |
Fine motor speed | −0.102 (1.085) | −0.084 (1.085) | −0.456 (1.037) | 0.0038 | −0.246 (0.995) | 0.3216 | −0.449 (1.028) | 0.0010 |
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Standardized scores (z-scores): executive function, verbal episodic memory, and overall cognition | ||||||||
Executive function | −0.038 (0.978) | −0.008 (0.976) | −0.661 (0.816) | <0.0001 | −0.544 (0.862) | 0.0003 | −0.633 (0.839) | <0.0001 |
Verbal episodic memory | 0.024 (0.932) | 0.076 (0.902) | −1.01 (0.813) | <0.0001 | −1.11 (1.104) | <0.0001 | −0.988 (0.926) | <0.0001 |
Overall cognition | −0.128 (0.962) | −0.077 (0.938) | −1.10 (0.887) | <0.0001 | −1.12 (0.906) | <0.0001 | −1.11 (0.902) | <0.0001 |
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IAV Cognitive Domains (standard deviation across cognitive domains at baseline) | ||||||||
SD | 0.806 (0.260) | 0.804 (0.259) | 0.811 (0.272) | 0.8182 | 0.917 (0.288) | 0.0042 | 0.843 (0.269) | 0.1475 |
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IAV time (slope of IAV Cognitive Domains across measurement occasions) | ||||||||
Slope SD | 0.003 (0.519) | −0.009 (0.512) | 0.221 (0.600) | 0.0017 | 0.281 (0.594) | 0.0002 | 0.237 (0.604) | 0.0001 |
Note. PMA vocabulary: primary mental abilities vocabulary (total correct − 1/3 number incorrect); letter fluency: letter fluency (number correct); category fluency: category fluency (number correct); BVRT: Benton Visual Retention Test (total figures with errors); CVLT (learning): California Verbal Learning Test (number correct 3 list A trials); CVLT (short-delay free-recall): California Verbal Learning Test (number correct list A short-delay free recall); CVLT (long-delay free-recall): California Verbal Learning Test (number correct list A long-delay free-recall); digits forward: digit span forward (number correct); digits backward: digit span backward (number correct); card rotations: card rotations (total correct − total incorrect); finger tapping (dominant): finger tapping test (taps for dominant hand); finger tapping (nondominant): finger tapping test (taps for nondominant hand); *higher scores reflect poorer performance.