Table 1.
Patient demographics and basic clinical data.
| Variable | Data Distribution |
|---|---|
| n | |
| Sex (Male/Female) | 18:13 |
| Handedness (Right/Left) | 29:2 |
| Hand more affected by ET (Right/Left) | 11:20 |
| Daytime stimulation adjustments (Yes/No) | 15:16 |
| Overnight stimulation switch off (Yes/No/Lower) | 9:21:1 |
| Family history of ET (Yes/No, n = 21) | 17:4 |
| Tremor improved by alcohol? (Yes/No, n = 17) | 12:5 |
| Frequent consumption of alcohol? (Yes/No) | 2:29 |
| Smoking (Yes/No) | 6:25 |
| Consumption of illicit drugs (Yes/No) | 0:31 |
| Tremor-related medication? (Yes/No) | 10:21 |
| Comorbidities | |
| Spinal stenosis (Yes/No) | 1:30 |
| Pre-existing Cerebellar disease (Yes/No) | 0:31 |
| Previous Chemotherapy (Yes/No) | 1:30 |
| Polyneuropathy (Yes/No) | 8:23 |
| Diabetes mellitus (Yes/No) | 12:19 |
| Mean ± SD (range) | |
| Age | 72.06 ± 8.6 (52–85) |
| Disease onset (years) | 31.06 ± 18.6 (6–67) |
| Disease duration (years) | 39.97 ± 18.4 (4–65) |
| Time since DBS implantation (years) | 6.4 ± 4.4 (1.5-–18) |
| Medication | |
| Propranolol (mg, n = 5) 1 | 88 ± 43 (40–160) |
| Primidone (mg, n = 3) 1 | 437.5 ± 187.5 (250–625) |
| Gabapentin (mg, n = 1) | 1600 |
| Topiramate (mg, n = 1) | 50 |
| Clonazepam (mg, n = 1) | 1.5 |
| FTMTRS preOP (n = 16) | 41 ± 11 (31–67) |
| FTMRS 12M ON (n = 14) | 16 ± 13 (0–38) |
| FTMTRS ON | 36 ± 21 (4–92) |
| FTMTRS OFF | 65 ± 22 (13–112) |
| Ratio FTMTRS nowON/preOP (n = 16) | 0.87 ± 0.52 (0.12–1.9) |
| SARA without item 6 ON | 7.4 ± 4.3 (1–16) |
| SARA without item 6 OFF | 6.5 ± 4.5 (0–18) |
| Step Length ON (meters) (n = 27) 2 | 0.41 ± 0.09 (0.25–0.57) |
| Step Length OFF (meters) (n = 23) 3 | 0.44 ± 0.07 (0.30–0.53) |
| Postural Tremor Frequency ON Mean (Hz) | 6.0 ± 1.2 (3.4–8.4) |
| Postural Tremor Frequency OFF Mean (Hz) | 4.9 ± 1.1 (3.3–7.8) |
| Postural Tremor Frequency OFF Right (Hz) | 5.0 ± 1.3 (3.5–8.2) |
| Postural Tremor Frequency OFF Left (Hz) | 4.8 ± 1.1 (3.0–7.4) |
| QUEST | |
| Health Overall | 70 ± 20 (30–100) |
| Quality of Life Overall | 71 ± 20 (31–100) |
| Communication | 19.4 ± 23.1 (0–75) |
| Work and Finances | 14.8 ± 24.1 (0–100) |
| Hobbies | 38.2 ± 34.4 (0–91.7) |
| Physical | 51.5 ± 35.3 (0–100) |
| Psychosocial | 22.8 ± 22.5 (0–86.1) |
Note: If not indicated otherwise, data were acquired at the main study visit (“now”). Where there are no numbers in parentheses in the variable column, data from all 31 patients were available. 1 One patient took propranolol and primidone. 2 A total of 4 participants could not perform the gait analysis due to the unavailability of motion capture systems. 3 A total of 4 participants could not perform the gait analysis because of a too-unsteady gait at OFF. Abbreviations: ET, essential tremor; SD, standard deviation; DBS, deep brain stimulation; FTMTRS, Fahn–Tolosa–Marin Tremor Rating Scale; 12M, at 12 months postoperatively; OFF, stimulation OFF state; ON, stimulation ON state; preOP, preoperative; SARA, scale for the assessment and rating of ataxia; QUEST, Quality of Life in Essential Tremor Questionnaire.