Table 1. Baseline characteristics according to impairment status.
| NI | PI | CI | CPI | |
|---|---|---|---|---|
| N | 217 | 169 | 158 | 220 |
| Age, yrs. | 73.76±7.66 | 80.56±9.00 | 73.49±7.13 | 79.19±7.92 |
| % female | 56.2 | 69.2 | 44.3 | 59.6 |
| % white | 94.5 | 88.2 | 92.4 | 86.4 |
| Education, yrs. | 14.84±2.83 | 14.37±3.13 | 14.39±3.07 | 13.10±3.18 |
| Total PPT | 30.53±1.75 | 22.18±6.37 | 30.09±1.87 | 21.71±5.88 |
| PPT—gait items | 20.69±1.39 | 14.49±4.70 | 20.45±1.57 | 14.51±4.26 |
| PPT—non-gait items | 9.84±1.16 | 7.69±2.21 | 9.65±1.11 | 7.20±2.29 |
| CDR-SB | 0.04±0.14 | 0.07±0.1 | 3.11±1.75 | 3.82±2.58 |
| TMA | 36.58±13.40 | 46.23±18.60 | 54.41±31.37 | 74.56±37.25 |
| TMB | 91.37±35.98 | 119.45±39.41 | 133.52±47.21 | 158.08±33.69 |
| Word fluency | 31.15±10.22 | 28.20±11.07 | 23.37±10.74 | 18.73±8.99 |
| BNT | 55.64±4.81 | 52.51±6.18 | 47.06±10.19 | 41.54±13.40 |
| Composite cognitive score | 0.33±0.88 | -0.41±0.96 | -1.45±1.44 | -2.39±1.51 |
| Frontal factor score | 0.59±0.66 | 0.32±0.68 | 0.07±0.77 | -0.26±0.76 |
| Temporal factor score | 1.41±0.60 | 1.06±0.69 | 0.12±0.81 | -0.20±0.82 |
| Parietal factor score | 1.00±0.53 | 0.56±0.52 | 0.33±0.75 | -0.24±0.78 |
Notes: NI = not impaired, PI = physically impaired but cognitively normal, CI = cognitively impaired but physically normal, CPI = cognitively and physically impaired; PPT = Physical Performance Test; CDR-SB = CDR Sum of boxes; TMA = Trail making part A; TMB = Trail making part B; BNT = Boston Naming test; All (overall) differences are statistically significant at p<0.001, with the exception of race which was significant at p<0.05. Individuals who were NI at baseline tended to perform best while individuals who were CPI at baseline tended to perform the worst.