Table 1
Clinical characteristics.
| CLINICAL CHARACTERISTICS | MEAN | SD | MEDIAN | RANGE | % |
|---|---|---|---|---|---|
| Age | 67.7 | 10.7 | 70 | 34–83 | |
| Disease duration | 11 | 7.1 | 10 | 1–29 | |
| Years to diagnosis | 7 | 6.3 | 4.5 | 1–21 | |
| Females | 73% | ||||
| Males | 27% | ||||
| Caucasian | 98% | ||||
| Asian | 2% | ||||
| First degree relative with orthostatic tremor | 7.7% | ||||
| First degree relative with other tremor disorder | 7.7% | ||||
| First degree relative with other neurodegenerative disorder | 15.4% | ||||
| Up to 12 years education | 19.6% | ||||
| Vocational education | 11.5% | ||||
| University/college education | 69.2% | ||||
| No present alcohol use | 13.5% | ||||
| Low alcohol use (<10 stdgl/w) | 71.2% | ||||
| High alcohol use (>10 stdgl/w) | 15.4% | ||||
| No tobacco use | 42.3% | ||||
| Previous tobacco use | 48.1% | ||||
| Present tobacco use | 7.7% | ||||
| No exposure to harmful substances, head trauma or private well | 42.3% | ||||
| Exposure to harmful substances (pesticides, solvents, heavy metals) | 21.2% | ||||
| History of mild to moderate head trauma | 19.2% | ||||
| Regular drinking from private well | 21.2% | ||||
[i] Clinical characteristics of patients with POT. SD = standard deviation. Stgl/w = standard glasses/week.
Table 2
Subjective reports of disease severity and treatments.
| DISEASE SEVERITY | |||||
|---|---|---|---|---|---|
| WALKING AID | WALKING DISTANCE | TOLERATED TIME IN STANDING | |||
| Wheelchair | 3.8% | <100 m | 3.8% | <30 seconds | 17.5% |
| Walker | 15.4% | 0.1–1 km | 15.4% | 30–60 seconds | 15.7% |
| Walking sticks | 11.5% | 1–2 km | 3.8% | 1–2 minutes | 15.7% |
| None | 69.2% | 2–5 km | 9.6% | 2–5 minutes | 33.3% |
| >5 km | 67.3% | 5–10 minutes | 5.9% | ||
| >10 minutes | 11.8% | ||||
| TREATMENTS | PARTICIPANTS (N) | POSITIVE EFFECT | |||
| Clonazepam | 24 | 41.7% | |||
| Gabapentin | 24 | 45.8% | |||
| Propranolol | 26 | 42.3% | |||
| Primidone | 5 | 20% | |||
| Perampanel | 4 | 75% | |||
| Valproic acid | 4 | 0% | |||
| Zonisamide | 2 | 0% | |||
| Dopaminergic medications | 2 | 0% | |||
| Deep Brain Stimulation | 2 | 50% | |||
[i] Disease severity presented as percentage of the study population using walking aids, reported maximum walking distance and reported tolerated time in standing. Previous and current treatments for orthostatic tremor presented as number of participants and percentage of participants reporting positive effect.
Table 3
Rating scales and questionnaires.
| RATING SCALES AND QUESTIONNAIRES | MEAN | SD | MEDIAN | RANGE | |||
|---|---|---|---|---|---|---|---|
| OTIP total (0–188) | 52.8 | 34.3 | 43 | 0–144 | |||
| OTIP part 1–4 (0–112) | 31.3 | 24 | 24 | 0–102 | |||
| OTIP part 5 (0–76) | 20.9 | 16 | 18 | 0–54 | |||
| OT-10 (0–50) | 23.7 | 9.8 | 24 | 0–41 | |||
| FTM TRS (0–144) | 11.3 | 7.3 | 9 | 3–34 | |||
| Head tremor | 4% | ||||||
| Tongue tremor | 44% | ||||||
| Postural arm tremor | 48% | ||||||
| Action/intention arm tremor | 21% | ||||||
| Postural leg tremor | 33% | ||||||
| Action/intention leg tremor | 8% | ||||||
| UPDRS I-II (0–68) | 7.4 | 3.9 | 7 | 2–19 | |||
| Reported falling <12 months | 30% | ||||||
| Freezing of gait | 42% | ||||||
| UPDRS III (0–100) | 5.6 | 5.8 | 4 | 0–24 | |||
| Mild (1p) | Moderate (2–3p) | Severe (4p) | |||||
| Rigidity | 25% | 12% | 0% | ||||
| Bradykinesia | 37% | 8% | 0% | ||||
| Rest tremor | 2% | 0% | 0% | ||||
| Postural instability | 36% | 15% | 4% | ||||
| Schwab & England ADL scale (0–100%) | 79.4 | 14 | 80 | 50–100 | |||
| Independent in ADL (80–100%) | 65% | ||||||
| EQ5D VAS (0–100) | 66.1 | 18 | 70 | 31–93 | |||
| EQ5D | No problem | Some problem | Extreme problem | ||||
| Mobility | 65% | 35% | 0% | ||||
| Hygiene | 88% | 10% | 2% | ||||
| Daily activities | 61% | 33% | 6% | ||||
| Pain/discomfort | 19% | 77% | 4% | ||||
| Anxiety/depression | 40% | 56% | 4% | ||||
| HADS (0–42) | 8.4 | 6.3 | 7 | 0–27 | |||
| Normal (anxiety 0–7p, depression 0–7p) | 75% | ||||||
| Anxiety (8–21p), no depression (0–7p) | 13.5% | ||||||
| Depression (8–21p), no anxiety (0–7p) | 3.8% | ||||||
| Anxiety (8–21p) and depression (8–21p) | 7.7% | ||||||
| MADRS (0–54) | 8.5 | 6.4 | 8 | 0–25 | |||
| Normal (0–12p) | 76.5% | ||||||
| Mild depression (13–19 p) | 15.7% | ||||||
| Moderate depression (20–34 p) | 7.8% | ||||||
| Severe depression (>35p) | 0% | ||||||
| MoCA (0–30) | 26.4 | 2.7 | 27 | 19–30 | |||
| Normal (26–30p) | 69% | ||||||
| Mild cognitive impairment (18–25p) | 31% | ||||||
[i] Results from rating scales and questionnaires presented as mean, SD, median, range and percentage of study population. SD = standard deviation. OTIP = Orthostatic tremor impact profile. OT-10 = Orthostatic tremor Severity and disability scale. FTM TRS = Fahn Tolosa Marín tremor rating scale. S&E ADL = Schwab and England activities of daily life scale. EQ VAS = Euroqol visual analogue scale. HADS = Hospital anxiety and depression scale. MADRS = Montgomery Asberg depression rating scale. MoCA = Montreal cognitive assessment test.
Table 4
Correlation analysis.
| DISEASE DURATION | AGE | STANDING TIME | WALKING AID | WALKING DISTANCE | OTIP TOTAL | OTIP 1-4 | OTIP 5 | OT-10 | |
|---|---|---|---|---|---|---|---|---|---|
| Standing time | 0.01569 | 0.012173 | |||||||
| Walking aid | 0.009334 | 0.004828 | 0.000666 | ||||||
| Walking distance | 0.421807 | 0.003717 | 0.000284 | <.00001 | |||||
| OTIP total | 0.499753 | 0.097781 | <.00001 | 0.000652 | <.00001 | ||||
| OTIP 1-4 | 0.105749 | 0.006905 | <.00001 | <.00001 | <.00001 | <.00001 | |||
| OTIP 5 | 0.373048 | 0.716388 | 0.001838 | 0.956795 | 0.159408 | <.00001 | 0.003389 | ||
| OT-10 | 0.148923 | 0.039986 | <.00001 | <.00001 | 0.000096 | <.00001 | <.00001 | 0.005633 | |
| FTM TRS | 0.007393 | 0.005084 | 0.008499 | 0.048743 | 0.313914 | 0.120183 | 0.041088 | 0.770201 | 0.061433 |
| UPDRS III | 0.043444 | 0.024341 | 0.373048 | 0.009527 | 0.386175 | 0.292759 | 0.011701 | 0.178927 | 0.03898 |
| S&E ADL | 0.140713 | 0.015525 | 0.00022 | <.00001 | 0.00014 | <.00001 | <.00001 | 0.046563 | 0.000017 |
| EQ VAS | 0.354238 | 0.132856 | 0.001171 | 0.024728 | 0.012093 | <.00001 | <.00001 | <.00001 | 0.000125 |
| HADS | 0.782076 | 0.503813 | 0.009441 | 0.406371 | 0.092686 | <.00001 | 0.000286 | <.00001 | 0.010542 |
| MADRS | 0.597691 | 0.960158 | 0.01008 | 0.975303 | 0.345419 | <.00001 | 0.002131 | <.00001 | 0.02321 |
| MoCA | 0.409997 | 0.089313 | 0.294074 | 0.100941 | 0.000244 | 0.097336 | 0.01633 | 0.981476 | 0.129498 |
[i] Correlation between disease severity and results from rating scales and questionnaires. Pearson correlation and Bonferroni correction for multiple comparison. P-values presented were considered significant when p < 0.0025, marked as bold. OTIP = Orthostatic tremor impact profile. OT-10 = Orthostatic tremor Severity and disability scale. FTM TRS = Fahn Tolosa Marín tremor rating scale. S&E ADL = Schwab and England activities of daily life scale. EQ VAS = Euroqol visual analogue scale. HADS = Hospital anxiety and depression scale. MADRS = Montgomery Asberg depression rating scale. MoCA = Montreal cognitive assessment test.
Figure 1
Patient-reported difficulties with activities of daily life according to Schwab & England Activities of Daily Life scale.