Table 1.
Demographic characteristics of the subjects
| Control (n = 20) | PD (n = 20) | PDD (n = 20) | P value | |
|---|---|---|---|---|
| Sex, male : female | 10 : 10 | 8 : 12 | 10 : 10 | NS |
| Age in years, mean (SD) | 72.7 (3.3) | 71.6 (4.3) | 71.7 (5.3) | NS |
| Disease duration in months, mean (SD) | NA | 94.0 (53.4) | 146.6 (91.0) | <0.05 (PD vs PDD) |
| Hoehn–Yahr stage (SD) | 0 | 2.4 (1.0) | 2.9 (0.7) | <0.05 (PD vs PDD) |
| MMSE (SD)a | 28.8 | 25.7 (3.2) | 18.7 (5.8) | <0.01 (PD vs PDD) |
| Levodopa dosage mg/day, median (SD) | 0 | 464.2 (175.0) | 673.3 (120.0) | <0.05 (PD vs PDD) |
PD Parkinson’s disease, PDD Parkinson’s disease with dementia, MMSE Mini-Mental State Examination, NA not applicable, NS not significant (P > 0.05)
aMMSE scores were significantly lower in PDD patients than in controls (P < 0.01) or PD patients (P < 0.01), but the scores did not differ significantly between controls and PD patients