Figure 1
(A) The study included three visits and four weeks of home therapy use. (B) The TAPS device included a stimulator, band and base station. (C) The TAPS device automatically calibrated stimulation to alternate between the patient’s median and radial nerves at the tremor frequency measured by an onboard triaxial accelerometer. (D) Patients performed a device-prompted postural hold for calibration and measurements of tremor power during home use.
Table 1
Enrolled patient characteristics.
| DEMOGRAPHICS | |
|---|---|
| Gender, female | 25% (10/40) |
| Age (years) | 67.1 ± 9.9 (41–85) |
| Race | |
| Asian | 15% (6/40) |
| Black or African American | 3% (1/40) |
| White | 83% (33/40) |
| Ethnicity | |
| Hispanic or Latino | 8% (3/40) |
| Not Hispanic or Latino | 88% (35/40) |
| Unknown or not reported | 5% (2/40) |
| CLINICAL CHARACTERISTICS1 | |
| Age at onset of first PD symptom (years) | 60.5 ± 10.0 (38–82) |
| Age at onset of hand tremor (years) | 61.1 ± 9.7 (39–82) |
| Age diagnosed (years) | 61.9 ± 9.9 (38–82) |
| Duration from onset (years) | 6.6 ± 3.8 (1–16) |
| Duration from hand onset (years) | 6.0 ± 3.6 (1–16) |
| Duration from diagnosis (years) | 5.2 ± 3.1 (1–13) |
| On any PD medication | 98% (39/40) |
| MDS-UPDRS action tremor2 | 1.7 ± 0.5 (1–4) |
| MDS-UPDRS treated hand3 | 1.7 ± 0.6 (1–4) |
| BF-ADL treated hand4 | 2.0 ± 0.5 (1–4) |
[i] Categorical data reported as percentage (N/40); Continuous data reported as mean ± 1 standard deviation (range). 1At enrollment (Visit 0). 2Average of MDS-UPDRS postural tremor and kinetic tremor scores (questions 3.15 and 3.16, respectively). 3Average of six MDS-UPDRS upper limb tasks (questions 3.4–3.6 and 3.15–3.17 evaluated on treated limb). 4Average of eight BF-ADL tasks evaluated on treated limb.
Figure 2
Tremor improvement as measured by motion sensors (primary endpoint). TAPS improved tremor during a month of unsupervised home use, with 50% of patients showing at least 2.7-fold improvement (median, 64%; interquartile range, 54%–79%) improvement with 79% of patients improved at least 2-fold and 97% of patients improved.
Figure 3
Tremor improvement in the dominant hand while in a medication-off state during visits as rated by clinicians on MDS-UPDRS and by patients on BF-ADL (co-secondary endpoints) (Visit 1, N = 39; Visit 2, N = 35). (A) TAPS improved clinician-ratings of average postural and kinetic tremor tasks on MDS-UPDRS (rated on a scale of 0 to 4) at each supervised stimulation session. (B) TAPS improved patient-ratings of average BF-ADL tasks (rated on a scale of 1 to 4) at each supervised stimulation session. (C) Responder rates varied across individual MDS-UPDRS III items for pre-stimulation of visit 1 to post-stimulation of visit 2. See Supplemental Table 1 and 2 for MDS-UPDRS and BF-ADL ratings across all tasks and visits. Error bars represent mean ± 1 standard error and significance (*) was tested at p < 0.05.
Figure 4
Clinician- and patient-rated impressions of improvement during visits. Clinicians rated motor symptoms as improved in 77.5% (visit 1) and 83% (visit 2) of patients (CGI-I) Seventy-five percent (visit 1) and 80% (visit 2) of patients self-rated improvement in motor symptoms (PGI-I) (Visit 1 N = 39, Visit 2 N = 35).