Table 2 Characteristics of subgroups of patients with normal or impaired cognition.
| Characteristics | Normal cognition (n = 309)* | Impaired cognition (n = 88)* | Comparison between groups |
|---|---|---|---|
| Men (n (%)) | 189 (61) | 62 (71) | χ2 = 2.542, p = 0.111§ |
| Age (y) (mean (SD)) | 59.4 (11.1) | 65.4 (10.9) | t = −4.446, p<0.001¶ |
| Education (y) (mean (SD)) | 12.1 (4.0) | 11.5 (4.2) | t = 1.259, p = 0.209¶ |
| Disease duration (y) (mean (SD)) | 10.0 (6.2) | 12.4 (7.0) | t = −3.097, p = 0.002¶ |
| Age at onset (y) (mean (SD)) | 49.4 (11.7) | 53.0 (11.5) | t = −2.539, p = 0.011¶ |
| Hoehn and Yahr stage (n (%))† | |||
| 1 | 13 (4) | 1 (1) | |
| 2 | 162 (52) | 31 (35) | |
| 3 | 90 (29) | 22 (25) | χ2 = 24.979, p<0.001§ |
| 4 | 37 (12) | 28 (32) | |
| 5 | 6 (2) | 4 (5) | |
| Missing | 1 (0) | 2 (2) | |
| Levodopa therapy (n (%)) | 203 (66) | 72 (82) | χ2 = 8.364, p = 0.004§ |
| Levodopa dose (mg/day) (mean (SD)) | 638.1 (341.9) | 759.8 (454.4) | t = −2.073, p = 0.041¶ |
| Dopamine agonists therapy (n (%)) | 222 (72) | 60 (68) | χ2 = 0.447, p = 0.504§ |
| Anticholinergics (n (%)) | 41 (13) | 18 (21) | χ2 = 2.795, p = 0.095§ |
| SCOPA‐COG score (mean (SD)) | |||
| Absolute value | 28.0 (4.6) | 17.6 (3.7) | t = 21.992, p<0.001¶ |
| %‡ | 65.0 (10.6) | 40.9 (8.6) | t = 21.992, p<0.001¶ |
| MMSE score (mean (SD)) | |||
| Absolute value | 27.5 (2.0) | 24.3 (3.2) | t = 9.056, p<0.001¶ |
| %‡ | 91.8 (6.6) | 81.0 (10.6) | t = 9.056, p<0.001¶ |
| SPES‐SCOPA motor score (mean (SD)) | |||
| %‡ | 30.4 (10.8) | 37.6 (12.7) | t = 4.857, p<0.001¶ |
| SCOPA‐AUT score (mean (SD)) | |||
| %‡ | 25.2 (12.0) | 29.2 (13.0) | t = −2.736, p = 0.007¶ |
| BDI score (mean (SD)) | |||
| %‡ | 15.5 (10.2) | 19.1 (11.8) | t = −2.787, p = 0.006¶ |
| mPPRS score (mean (SD)) | |||
| %‡ | 10.3 (9.7) | 18.0 (13.5) | t = −4.988, p<0.001¶ |
BDI, Beck Depression Inventory; MMSE, Mini‐Mental State Examination; mPPRS, modified Parkinson Psychosis Rating Scale; SCOPA‐AUT, SCales for Outcomes in PArkinson's disease‐autonomic function; SCOPA‐COG, SCales for Outcomes in PArkinson's disease‐COGnition.
*Numbers do not add up to group total because of missing values.
†Sum of percentages does not equal 100 because of rounding off.
‡Absolute value transformed to 0–100 scale.
§χ2 test results.
¶Student's t test for independent sample results.