Table 1.
Baseline demographic and clinical characteristics of cohort
| Variable | Control (n = 99) | PD (n = 211) | t/Z | p | ||
| Mean | SD | Mean | SD | |||
| Age (y) | 67.9 | 8.2 | 65.9 | 9.8 | 1.8 | 0.690 |
| Education (y) | 13.1 | 3.4 | 12.8 | 3.6 | –0.9 | 0.381 |
| NART | 115.9 | 8.7 | 114.4 | 10.3 | –0.8 | 0.434 |
| PD duration (mo) | 5.6 | 5.1 | ||||
| MDS UPDRS III total | 27.4 | 11.8 | ||||
| Hoehn &Yahr stage | 1.9 | 0.7 | ||||
| LEDD mg/day | 176.9 | 154.7 | ||||
| GDS-15 | 1.0 | 1.5 | 2.8 | 2.6 | –7.2 | < 0.001 |
| MoCA total | 27.0 | 2.5 | 25.4 | 3.4 | –3.7 | < 0.001 |
| MMSE total | 29.0 | 1.2 | 28.7 | 1.3 | –2.5 | 0.014 |
| Verbal fluency (F) | 13.0 | 4.7 | 11.9 | 4.8 | –2.0 | 0.047 |
| Semantic fluency (Animals) | 23.9 | 6.1 | 21.3 | 6.5 | 3.3 | 0.001 |
| OTS no. problems solved 1st choice | 16.4 | 2.5 | 14.6 | 4.0 | –4.0 | < 0.001 |
| PRM number correct | 20.7 | 2.5 | 19.7 | 3.2 | –2.8 | 0.005 |
| PRM % correct | 86.3 | 10.2 | 81.2 | 13.8 | –2.9 | 0.004 |
| SRM % correct | 80.7 | 9.2 | 76.0 | 11.6 | –3.0 | 0.003 |
| SRM number correct | 16.1 | 1.8 | 15.3 | 2.2 | –2.9 | 0.004 |
| PAL stages completed | 7.8 | 0.6 | 7.1 | 1.2 | –5.5 | < 0.001 |
| PAL total errors | 19.2 | 14.5 | 21.3 | 16.5 | –1.0 | 0.313 |
| PAL total trials | 14.1 | 3.7 | 14.8 | 4.4 | –1.0 | 0.297 |
| PAL mean trials to success | 1.8 | 0.6 | 2.0 | 0.8 | –1.7 | 0.090 |
| SRT mean (ms) | 315.3 | 63.0 | 361.7 | 125.8 | –4.7 | < 0.001 |
| DV accuracy % | 96.0 | 5.8 | 92.2 | 12.9 | –1.9 | 0.057 |
| DV mean (ms) | 452.0 | 44.8 | 476.9 | 56.8 | –3.6 | < 0.001 |
| CRT accuracy % | 97.0 | 2.7 | 97.2 | 2.5 | –0.6 | 0.574 |
| CRT mean (ms) | 510.6 | 60.3 | 540.8 | 94.5 | –2.4 | 0.018 |
| PoA (ms) | 1277.9 | 136.0 | 1379.3 | 235.4 | –3.9 | < 0.001 |
| PoA CoV | 50.2 | 10.2 | 54.0 | 11.7 | –2.5 | 0.014 |
| Continuity of Attention | 91.7 | 3.5 | 90.1 | 6.2 | –1.6 | 0.112 |
| Cognitive Reaction Time | 195.4 | 53.6 | 179.1 | 98.4 | –1.0 | 0.306 |
| SWM original stim accuracy % | 93.5 | 9.9 | 90.8 | 14.6 | –0.6 | 0.538 |
| SWM new stim accuracy % | 94.3 | 12.1 | 92.4 | 12.6 | –1.9 | 0.059 |
| SWM SI % | 0.9 | 0.2 | 0.8 | 0.2 | –1.0 | 0.318 |
| SWM original stim mean (ms) | 1121.0 | 456.3 | 1173.3 | 446.9 | –1.0 | 0.338 |
| SWM new stim mean (ms) | 1166.7 | 331.8 | 1261.6 | 495.6 | –0.8 | 0.402 |
| SWM mean (ms) | 1152.9 | 406.4 | 1221.5 | 459.8 | –0.8 | 0.398 |
| Pentagon score | 1.9 | 0.2 | 1.9 | 0.4 | –2.1 | 0.036 |
| Naming score | 2.9 | 0.4 | 2.9 | 0.3 | –0.9 | 0.351 |
| Sentence score | 1.7 | 0.6 | 1.6 | 0.6 | –1.4 | 0.148 |
| n | % | n | % | χ2 | p | |
| Gender: male | 54 | 54.5 | 113 | 63.0 | 2.0 | 0.154 |
| PD-MCI MoCA | 100 | 47.4 | ||||
| PD-MCI 1SD | 138 | 65.4 | ||||
| PD-MCI 1.5SD | 87 | 41.2 | ||||
| M PD-MCI 2SD | 44 | 20.9 | ||||
PD, Parkinson’s disease; SD, standard deviation; NART, National Adult Reading Test; MDS-UPDRS III, Movement Disorder Society Unified Parkinson’s Disease Rating Scale; LEDD, Levodopa equivalent daily dose; GDS-15, Geriatric Depression Scale; MoCA, Montreal Cognitive Assessment; MMSE, Mini-Mental State Examination; OTS, One Touch Stockings; PRM, paired recognition memory; SRM, spatial recognition memory; PAL, paired associated learning; CRT, choice reaction time; PoA, power of attention; CoV, coefficient of variance; SWM, spatial working memory; SI, sensitivity indices; PD-MCI, mild cognitive impairment with Parkinson’s disease.