Demographics and results of clinical assessments at baseline
| Characteristic | Controls n=26 | PD non-VH n=61 | PD-VH n=15 | P value |
| Age (years) | 67.4 (8.2) | 64.6 (8.1) | 64.5 (8.0) | 0.308 |
| Male (%) | 12 (46.2) | 36 (59.0) | 6 (40%) | 0.302 |
| Years of education | 17.9 (2.2) | 17.3 (2.6) | 16.9 (3.8) | 0.686 |
| Vision | ||||
| Contrast sensitivity (Pelli Robson)§ | 1.8 (0.2) | 1.8 (0.2) | 1.7 (0.2) | 0.136 |
| Acuity (LogMar)§ | −0.08 (0.2) | −0.07 (0.2) | −0.08 (0.1) | 0.136 |
| Colour vision (D15)§ | 1.2 (1.0) | 1.2 (1.0) | 1.6 (1.8) | 0.927 |
| General cognition | ||||
| MOCA | 29 (1.2) | 28.0 (2.3) | 27.6 (1.8) | 0.050‡ |
| MMSE | 29.2 (0.9) | 29.0 (1.2) | 28.9 (1.3) | 0.847 |
| Mood | ||||
| HADS anxiety | 3.5 (3.5) | 5.1 (3.5) | 8.0 (4.2) | 0.002*† |
| HADS depression | 1.2 (1.5) | 3.7 (3.1) | 4.8 (3.3) | <0.001†‡ |
| Detailed neuropsychology | ||||
| Attention | ||||
| Digit span forwards | 9.3 (2.1) | 9.1 (2.0) | 10 (2.0) | 0.412 |
| Digit span backwards | 6.9 (2.4) | 7.3 (2.2) | 7.6 (2.4) | 0.748 |
| Stroop: colour (sec) | 31.9 (7.6) | 32.6 (6.4) | 38.3 (8.5) | 0.012*‡ |
| Executive function | ||||
| Stroop: interference (sec) | 56.2 (14.3) | 40.3 (20.1) | 72.9 (26.6) | 0.029*‡ |
| Category fluency | 21.9 (4.8) | 22.1 (6.0) | 20.1 (4.0) | 0.502 |
| Memory | ||||
| Word recognition task | 24.5 (1.0) | 24.3 (2.3) | 23.8 (1.2) | 0.077 |
| Logical memory (delayed) | 12.8 (3.5) | 13.3 (4.6) | 13.5 (4.5) | 0.928 |
| Language | ||||
| Graded naming task | 23.6 (1.0) | 24.3 (2.5) | 23.5 (3.1) | 0.638 |
| Letter fluency | 17.8 (5.1) | 17.3 (5.3) | 16.1 (4.9) | 0.711 |
| Visuospatial | ||||
| Benton’s judgement of line orientation | 26 (3.4) | 25.3 (3.7) | 23.1 (4.8) | 0.134 |
| Hooper | 25.9 (2.1) | 25.0 (2.9) | 23.9 (3.1) | 0.082 |
| Disease-specific measures | ||||
| Years from diagnosis | – | 4.0 (2.5) | 4.5 (2.7) | 0.238 |
| UPDRS total score | – | 42.9 (19.4) | 57.8 (24.3) | 0.014 |
| UPDRS motor score | – | 22.7 (11.7) | 26.2 (15.2) | 0.052 |
| Right side affected at onset | – | 28 (45.9) | 4 (26.7) | 0.187 |
| RBDSQ | – | 3.8 (2.1) | 5.7 (2.4) | 0.003 |
| Sniffin sticks | – | 7.6 (2.9) | 6.9 (3.4) | 0.003 |
| LEDD | – | 427.1 (220.1) | 431.0 (233.1) | 0.951 |
All data shown are mean (SD) except gender and affected size.
In bold characteristics that significantly differed between groups.
For all neuropsychology measures, higher scores indicate better performance, except Stroop Colour and Interference where lower scores imply better performance.
*Statistically significant difference between PD-VH and PD non-VH.
†Statistically significant difference between PD non-VH and controls.
‡Statistically significant difference between PD-VH and controls.
§Best binocular score used; LogMAR and D15: lower score implies better performance, Pelli-Robson: higher score implies better performance.
HADS, Hospital Anxiety and Depression Scale (higher scores indicate increased anxiety and depression) LEDD, levodopa equivalent dose; MMSE, Mini-Mental State Examination; MOCA, Montreal Cognitive Assessment; PD, Parkinson’s disease; RBDSQ, REM sleep behaviour disorder scale; UPDRS, Unified Parkinson’s Disease Rating Scale; VH, visual hallucination.