Table 1
Clinical characteristics of ET and PD-TDT patients and HCs.
| ET | PD-TDT | HC | p-VALUE | |
|---|---|---|---|---|
| Number of subjects | 23 | 23 | 22 | – |
| Age (years old) | 69.3 ± 14.7 | 67.6 ± 10.3 | 70.8 ± 4.7 | 0.57 |
| Gender (male:female) | 18:5 | 15:8 | 13:9 | 0.37 |
| Onset age (years old) | 48.2 ± 21.7 | 62.6 ± 10.0 | NA | 0.007 ** |
| Tremor duration (years) | 21.1 ± 18.9 | 5.1 ± 3.5 | NA | <0.001 *** |
| Therapy duration (years) | 2.8 ± 3.3 | 3.7 ± 2.7 | NA | 0.11 |
| Nuclear medicine (n, %) | 23 (100%) | 23 (100%) | NA | – |
| DAT-SPECT (reduced/normal uptake) | 0/23 | 22/0 | NA | – |
| MIBG scintigraphy (reduced/normal uptake) | 0/3 | 11/8 | NA | – |
| QUEST | 18.3 ± 13.7 | NA | NA | – |
| PDQ-39 | NA | 20.4 ± 17.4 | NA | – |
[i] **p < 0.01, ***p < 0.001: ET versus PD-TDT.
Above values are the mean±SD, except gender (given as a ratio) and nuclear medicine (given as a number and percentage).
Abbreviations: DAT-SPECT: dopamine transporter single-photon emission computed tomography; ET: essential tremor; HC: healthy control; MIBG: 123I-metaiodobenzylguanidine myocardia; NA: not available; PD-TDT: Parkinson’s disease-tremor dominant type; PDQ-39: Parkinson’s Disease Questionnaire-39; QOL: quality of life; QUEST: Quality of Life in Essential Tremor Questionnaire.
Table 2
Frequency and severity of non-motor symptoms in ET and PD-TDT patients and HCs.
| ET | PD-TDT | HC | P-VALUE | COHEN’S D ET VS PD | COHEN’S D ET VS HC | COHEN’S D PD VS HC | |
|---|---|---|---|---|---|---|---|
| NMSQ total score | 5.0 ± 4.2 | 6.9 ± 4.2 ‡‡‡ | 2.4 ± 3.0 | <0.001 | 0.51 | 0.69 | 1.3 |
| NMSS total score | 19.5 ± 14.1 ††† | 33.5 ± 23.4 ‡‡‡ | 7.6 ± 9.0 | <0.001 | 0.72 | 1.0 | 1.5 |
| Cardiovascular | 1.0 ± 1.8 | 0.7 ± 1.2 | 0.2 ± 0.7 | 0.06 | 0.17 | 0.57 | 0.52 |
| Sleep/fatigue | 5.9 ± 4.7 †† | 8.4 ± 5.9 ‡‡‡ | 2.0 ± 3.7 | <0.001 | 0.43 | 0.94 | 1.3 |
| Mood | 0.6 ± 1.6 | 2.1 ± 4.8 ‡‡‡ | 0.05 ± 0.2 | 0.001 | 0.43 | 0.50 | 0.61 |
| Perceptual problems | 0.1 ± 0.5 | 0.9 ± 2.0 ‡‡ | 0.0 ± 0.0 | 0.02 | 0.51 | 0.37 | 0.61 |
| Attention/memory | 2.4 ± 3.3 †† | 3.7 ± 4.9 ‡‡ | 1.0 ± 2.7 | 0.003 | 0.30 | 0.48 | 0.68 |
| Gastrointestinal | 1.5 ± 3.1 | 5.2 ± 5.7 **, ‡‡‡ | 0.7 ± 1.5 | <0.001 | 0.78 | 0.34 | 1.1 |
| Urinary | 7.5 ± 8.9 | 9.4 ± 9.1 | 3.4 ± 3.1 | 0.07 | 0.22 | 0.61 | 0.89 |
| Sexual function | 0.1 ± 0.5 | 0.3 ± 0.6 | 0.2 ± 0.9 | 0.10 | 0.33 | 0.07 | 0.17 |
| Miscellaneous | 1.5 ± 3.5 | 2.9 ± 2.8 **, ‡‡‡ | 0.1 ± 0.4 | <0.001 | 0.44 | 0.57 | 1.4 |
| MDS-UPDRS Part IB total score | 5.4 ± 4.0 †† | 5.4 ± 3.0 ‡‡ | 2.5 ± 2.4 | 0.002 | 0,02 | 0.87 | 1.1 |
| Sleep problems | 1.2 ± 1.3 | 0.9 ± 1.0 | 0.5 ± 0.8 | 0.07 | 0.28 | 0.72 | 0.52 |
| Daytime sleepiness | 1.0 ± 0.9 | 1.0 ± 0.9 | 0.7 ± 0.8 | 0.31 | 0.0 | 0.50 | 0.50 |
| Pain and other sensations | 0.6 ± 0.9 | 0.5 ± 0.5 | 0.2 ± 0.4 | 0.16 | 0.19 | 0.57 | 0.53 |
| Urinary problems | 0.9 ± 1.1 † | 0.9 ± 0.9 ‡‡ | 0.2 ± 0.4 | 0.004 | 0.04 | 0.83 | 1.1 |
| Constipation problems | 0.5 ± 0.9 | 1.0 ± 1.0 ‡‡ | 0.4 ± 0.8 | 0.02 | 0.55 | 0.14 | 0.71 |
| Lightheadedness on standing | 0.5 ± 0.8 | 0.3 ± 0.5 | 0.1 ± 0.5 | 0.13 | 0.27 | 0.53 | 0.36 |
| Fatigue | 0.7 ± 0.7 | 0.8 ± 0.7 | 0.5 ± 0.6 | 0.28 | 0.18 | 0.30 | 0.49 |
| MMSE | 28.3 ± 1.9 | 29.0 ± 1.6 | 29.4 ± 1.0 | 0.09 | 0.35 | 0.70 | 0.34 |
| MoCA-J | 25.3 ± 3.1 | 26.2 ± 2.9 | 26.9 ± 2.5 | 0.17 | 0.27 | 0.54 | 0.26 |
| CDT | 8.9 ± 1.2* | 9.6 ± 0.8 | – | 0.04 | 0.65 | – | – |
| OSIT-J | 8.3 ± 2.3 | 5.1 ± 2.8 ***, ‡‡‡ | 8.9 ± 1.9 | <0.001 | 1.3 | 0.25 | 1.6 |
| HHIE | 4.6 ± 7.4 | 4.4 ± 7.1 | 4.2 ± 7.2 | 0.96 | 0.04 | 0.03 | 0.001 |
| GAD-7 | 2.5 ± 3.3 | 2.7 ± 4.2 | 1.4 ± 3.0 | 0.12 | 0.04 | 0.36 | 0.35 |
| GDS-15 | 3.8 ± 3.6 | 4.2 ± 4.1 | 2.1 ± 2.6 | 0.14 | 0.10 | 0.55 | 0.62 |
| ET | PD-TDT | HC | p-value | OR ET vs PD | OR ET vs HC | OR PD vs HC | |
| RBD1Q (positive, n (%)) | 2 (8.7) | 6 (26.1) ‡ | 0 (0) | 0.02 | 3.7 | – | – |
[i] *p < 0.016, **p < 0.01, ***p < 0.001: ET versus PD-TDT.
†p < 0.016, ††p < 0.01, †††p < 0.001: ET versus HC.
‡p < 0.016, ‡‡p < 0.01, ‡‡‡p < 0.001: PD-TDT versus HC.
Above p-values were adjusted using the Bonferroni method.
Values represent the means (±SD).
Abbreviations: CDT: clock drawing test; ET: essential tremor; GAD-7: Generalized Anxiety Disorder-7; GDS-15: Geriatric Depression Scale-15; HC: healthy control; HHIE: Hearing Handicap Inventory for the Elderly; MDS-UPDRS: Movement Disorder Society-Unified Parkinson’s Disease Rating Scale; MMSE: Mini Mental State Examination; MoCA-J: Japanese version of the Montreal Cognitive Assessment; NMSQ: Non-Motor Symptoms Questionnaire; NMSS: Non-Motor Symptoms Scale for Parkinson’s Disease; OR: Odds Ratio; OSIT-J: Odor Stick Identification Test for Japanese; PD-TDT: Parkinson’s disease-tremor dominant type; RBD1Q: Rapid Eye Movements Sleep Behavior Disorder Single-Question Screen.
Table 3
Results of motor symptom evaluation and a self-report questionnaire on tremor in patients with ET and PD-TDT.
| ET | PD-TDT | p-VALUE | |
|---|---|---|---|
| CRST total score, mean±SD | 30.9 ± 18.4 | 29.0 ± 12.0 | 0.92 |
| CRST Part A+B, mean±SD | 24.4 ± 14.8 | 23.7 ± 10.7 | 0.83 |
| CRST Part A, mean±SD | 12.8 ± 9.1 | 16.1 ± 7.7 | 0.14 |
| CRST Part B, mean±SD | 11.7 ± 6.5 | 7.7 ± 4.5 | 0.026 * |
| CRST Part C, mean±SD | 6.4 ± 4.5 | 5.3 ± 2.8 | 0.82 |
| MDS-UPDRS Part III, mean±SD | NA | 35.8 ± 13.4 | |
| Self-report questionnaire | |||
| Q1. Situations with worsening of tremor | |||
| Q1-1. Writing, n (%) | 12 (52.2) | 10 (43.5) | 0.56 |
| Q1–2. Eating, n (%) | 11 (47.8) | 5 (21.7) | 0.063 |
| Q1–3. Experiencing nervousness, n (%) | 15 (65.2) | 16 (69.6) | 0.75 |
| Q1–4. Resting, n (%) | 2 (8.7) | 9 (39.1) | 0.016* |
| Q2-1. Drinking habits, n (%) | 17 (73.9) | 15 (65.2) | 0.52 |
| Q2-2. Improvement of tremor with drinking, n (%) | 10 (58.8) | 11 (73.3) | 0.39 |
| Q3. Family history of tremor, n (%) | 9 (39.1) | 3 (13.0) | 0.044* |
| Q4. Family history of Parkinson’s disease, n (%) | 4 (17.4) | 3 (13.0) | 0.50 |
[i] *p < 0.05: ET versus PD-TDT.
Abbreviations: CRST: Clinical Rating Scale of Tremor; ET: essential tremor; HC: healthy control; MDS-UPDRS: Movement Disorder Society-Unified Parkinson’s Disease Rating Scale; NA: not available; PD-TDT: Parkinson’s disease-tremor dominant type.
Figure 1
Relationship between quality of life and tremor severity (A-D) or activities of daily living (E) in ET patients.
Figure 2
Receiver operating characteristic curves for ET and PD-TDT using CRST Part B and OSIT-J.