Table 1.
Demographic and clinical characteristics of ET and PD patients.
| ET patients (n = 50) | PD patients (n = 50) | Significance | |
|---|---|---|---|
| Age (years) | 63.6 ± 15.3 | 68.0 ± 10.5 | t = 1.67, p = 0.10 |
| Female gender | 25 (50%) | 20 (40%) | χ2 = 1.01, p = 0.32 |
| Education (years) | 15.90 ± 3.70 | 15.90 ± 3.40 | t = 0.09, p = 0.93 |
| Right handed | 43 (86%) | 45 (90%) | χ2 = 0.71, p = 0.87 |
| Duration of tremor symptoms (years) | 21.10 ± 15.00 | 9.00 ± 6.60 | t = 5.21, p < 0.001 |
| Hoehn and yahr stage | |||
| I or II | Not applicable | 41 (82%) | Not applicable |
| III | 6 (12%) | ||
| IV or V | 3 (6%) | ||
| Caffeine intake on day of examination | 25 (50%) | 27 (54%) | χ2 = 0.16, p = 0.69 |
| ET or PD medications | |||
| Carbidopa/levodopa | 0 (0%) | 41 (82%) | χ2 = 69.49, p < 0.001 |
| Dopamine agonist | 0 (0%) | 12 (24%) | χ2 = 13.64, p < 0.001 |
| Anticholinergic agent | 0 (0%) | 0 (0%) | χ2 = 0.00, p = 1.00 |
| Amantidine | 0 (0%) | 7 (14%) | χ2 = 7.53, p = 0.01 |
| Propranolol | 18 (36%) | 0 (0%) | χ2 = 18.78, p < 0.001 |
| Other beta-blocker | 1 (2%) | 0 (0%) | χ2 = 1.01, p = 0.32 |
| Primidone | 12 (24%) | 0 (0%) | χ2 = 13.64, p < 0.001 |
| Other ET medication | 6 (12%) | 0 (0%) | χ2 = 6.38, p = 0.01 |
| Tremor-inducing medications | |||
| Antidepressant | 16 (32%) | 12 (24%) | χ2 = 0.79, p = 0.33 |
| Anti-anxiety | 6 (12%) | 10 (20%) | χ2 = 1.19, p = 0.27 |
| Lithium | 1 (2%) | 1 (2%) | χ2 = 0.00, p = 1.00 |
| Valproic acid | 0 (0%) | 2 (4%) | χ2 = 2.04, p = 0.15 |
| Steroids (i.e., prednisone) | 1 (2%) | 0 (0%) | χ2 = 2.04, p = 0.15 |
| Levothyroxine | 9 (18%) | 10 (20%) | χ2 = 0.07, p = 0.80 |
| Tacrolimus or cyclosporine | 0 (0%) | 0 (0%) | χ2 = 0.00, p = 1.00 |
| Theophylline | 0 (0%) | 0 (0%) | χ2 = 0.00, p = 1.00 |
| Albuterol | 2 (4%) | 1 (2%) | χ2 = 0.34, p = 0.56 |
| Botulinum toxin injections | 0 (0%) | 2 (4%) | χ2 = 2.04, p = 0.15 |
| Deep brain stimulation surgery | 0 (0%) | 5 (10%) | χ2 = 5.26, p = 0.02 |
| Finger-nose-finger maneuver | |||
| Kinetic tremor (present)a | 50 (100%) | 39 (78%) | χ2 = 12.36, p < 0.001 |
| Intention tremor (present) | 14 (28%) | 2 (4%) | χ2 = 10.71, p = 0.001 |
| Tremor rating on Archimedes spiral | 2.08 ± 0.69 | 0.98 ± 0.81 | MW = 6.25, p < 0.001 |
| Rest tremor on examination | |||
| Arms (present) | 3 (6%) | 20 (40%) | χ2 = 16.32, p < 0.001 |
| Legs (present) | 0 (0%) | 6 (12%) | χ2 = 6.38, p = 0.01 |
| Face (present) | 0 (0%) | 7 (14%) | χ2 = 7.53, p = 0.01 |
| Postural head tremor (present) | 22 (44%) | 6 (12%) | χ2 = 12.70, p < 0.001 |
| Facial hypomimia on examinationb | 0 (0%) | 34 (68%) | χ2 = 51.52, p < 0.001 |
| Limb bradykinesia on examinationb,c | 0 (0%) | 35 (70%) | χ2 = 53.85, p < 0.001 |
| UPDRS score on finger taps | 0.16 ± 0.37 | 1.96 ± 0.70 | MW = 8.63, p < 0.001 |
| Body bradykinesia on examinationb | 0 (0%) | 20 (40%) | χ2 = 25.00, p < 0.001 |
| UPDRS score of rising from chair | 0.00 ± 0.00 | 0.64 ± 1.01 | MW = 2.32, p = 0.02 |
t = Student’s t-test.
χ2 = Chi-square test.
MW = Mann–Whitney test.
aUsing a definition of present as a WHIGET score ≥ 1.
bUsing a UDPRS score ≥ 1.
cWhile the patient opens and closes either hand.