Table 1.
Cohort characteristics.
| Variable | All non-demented | Only CDR 0.5 non-demented | ||||||
|---|---|---|---|---|---|---|---|---|
|
| ||||||||
| PPG (mean±SD (range) or % (N)) | NACC-UDS (mean±SD (range) or % (N)) | Cohort comparison (estimate, 95% CI) | P-value | PPG (mean±SD (range) or % (N)) | NACC-UDS (mean±SD (range) or % (N)) | Cohort comparison (estimate, 95% CI) | P-value | |
| N | 358 | 6243 | 241 | 2263 | ||||
| Demographics | ||||||||
| Age (yrs) | 73.5±5.2 (65,88) | 76.9±7.3 (65,110) | 3.39 (2.83,3.96)1 | <.001 | 74.1±5.3 (65,88) | 77.4±7.2 (65,110) | 3.33 (2.60,4.07)1 | <.001 |
| Male | 44.1% (158) | 41.1% (2568) | 0.26 | 44.8% (108) | 49.9% (1130) | 0.13 | ||
| Race | <.001 | 0.006 | ||||||
| Asian | 2.5% (9) | 2.4% (150) | 2.9% (7) | 3.3% (74) | ||||
| Black | 5.6% (20) | 13.0% (809) | 5.4% (13) | 12.4% (281) | ||||
| White | 91.3% (327) | 82.5% (5151) | 90.9% (219) | 81.0% (1833) | ||||
| Other/Unknown | 0.6% (2) | 2.1% (131) | 0.8% (2) | 3.3% (75) | ||||
| Education (yrs) | 15.5±2.9 (5,24) | 15.2±3.3 (0,29) | −0.34 (−0.66,−0.03)1 | 0.033 | 15.5±3.0 (5,24) | 14.8±3.7 (0,29) | −0.71 (−1.12,−0.31)1 | <.001 |
| Clinical Dementia Rating | ||||||||
| CDR rating Distribution: | <.001 | N/A | ||||||
| 0 | 32.7% (117) | 63.8% (3980) | 0% (0) | 0% (0) | ||||
| 0.5 | 67.3% (241) | 36.2% (2263) | 100% (241) | 100% (2263) | ||||
| CDR-SB | 0.90±0.89 (0.0,3.5) | 0.47±0.81 (0.0,5.5) | −0.43 (−0.52,−0.33)1 | <.001 | 1.33±0.77 (0.5,3.5) | 1.26±0.89 (0.5,5.5) | −0.07 (−0.17,0.04)1 | 0.21 |
| Memory rating Distribution: | <.001 | 0.88 | ||||||
| 0 | 33.0% (118) | 64.6% (4034) | 0.4% (1) | 2.4% (54) | ||||
| 0.5 | 59.8% (214) | 31.1% (1939) | 88.8% (214) | 85.7% (1939) | ||||
| 1 | 7.3% (26) | 4.3% (267) | 10.8% (26) | 11.8% (267) | ||||
| 2 | 0.0% (0) | 0.0% (3) | 0.0% (0) | 0.1% (3) | ||||
| Neuropsych scores | ||||||||
| MMSE | 29.2±1.1 (24,30) | 28.3±2.0 (7,30) | −0.93 (−1.06,−0.81)1 | <.001 | 29.1±1.2 (24,30) | 27.3±2.4 (7,30) | −1.74 (−1.92,−1.56)1 | <.001 |
| Digit-span forwards | 6.9±1.3 (4,9) | 6.6±1.1 (0,8) | −0.33 (−0.47,−0.19)1 | <.001 | 6.8±1.3 (4,9) | 6.4±1.2 (0,8) | −0.44 (−0.61,−0.26)1 | <.001 |
| Digit-span backwards | 5.3±1.4 (0,8) | 4.7±1.2 (0,7) | −0.62 (−0.77,−0.47)1 | <.001 | 5.2±1.4 (0,8) | 4.4±1.2 (0,7) | −0.77 (−0.96,−0.58)1 | <.001 |
| Trail making B (sec) | 103±53.1 (23,300) | 114±65.9 (17,300) | 11.2 (5.46,17.0)1 | <.001 | 108±59.5 (32,300) | 140±76.0 (22,300) | 32.3 (24.1,40.5)1 | <.001 |
| CVLT total | 48.3±11.5 (15,75) | N/A | N/A | . | 46.6±11.7 (15,73) | N/A | N/A | . |
| SRT free | 41.4±8.3 (10,59) | N/A | N/A | . | 40.6±8.8 (10,58) | N/A | N/A | . |
| Delayed logical memory | N/A | 10.4±5.0 (0.0,24.0) | N/A | . | N/A | 7.6±4.9 (0.0,23.0) | N/A | . |
| Memory Z-score | −.29±1.02 (−3.8,2.0) | −.38±1.17 (−2.8,2.8) | −0.09 (−0.20,0.02)1 | 0.102 | −.43±1.06 (−3.8,1.7) | −1.0±1.15 (−2.8,2.5) | −0.61 (−0.76,−0.46)1 | <.001 |
| Follow-up characteristics | ||||||||
| 2-yr timepoint to AD or censoring (yrs) | 5.89±3.60 (0.8,12.1) | 1.85±0.76 (0.4,4.0) | −4.03 (−4.50,−3.57)1 | <.001 | 5.90±3.74 (0.8,12.1) | 1.67±0.71 (0.4,3.6) | −4.23 (−4.83,−3.62)1 | <.001 |
| CDR-SB slope to 2-yr timepoint (/yr) | 0.14±0.29 (−0.5,1.3) | 0.06±0.32 (−2.0,3.8) | −0.08 (−0.12,−0.04)1 | <.001 | 0.18±0.33 (−0.5,1.3) | 0.03±0.47 (−2.0,2.6) | −0.15 (−0.21,−0.08)1 | <.001 |
| CDR-SB last obs 2-yr timepoint | 1.23±1.11 (0.0,5.0) | 0.65±1.31 (0.0,18.0) | −0.58 (−0.70,−0.46)1 | <.001 | 1.70±1.02 (0.0,5.0) | 1.55±1.78 (0.0,18.0) | −0.15 (−0.30,0.01)1 | 0.060 |
| MMSE slope to 2-yr timepoint (/yr) | 0.00±0.48 (−1.5,1.8) | −.10±0.86 (−3.9,10.6) | −0.10 (−0.17,−0.03)1 | 0.005 | −.01±0.52 (−1.5,1.8) | −.19±1.11 (−3.4,10.6) | −0.18 (−0.30,−0.07)1 | 0.002 |
| AD after 2-yr timepoint | 25.5% (59) | 5.5% (158) | 1.15 (0.72,1.84)3 | 0.55 | 34.5% (51) | 13.6% (103) | 2.06 (1.26,3.37)3 | 0.004 |
1
Mean difference = mean(NACC-UDS) − mean(PPG)
2
Odds ratio = odds(NACC-UDS) / odds(PPG)
3
Hazard ratio = hazard(NACC-UDS) / hazard(PPG)