Home-Based taVNS in PD
(2026)Objective
Test whether 3 weeks of home-based, twice-daily transcutaneous auricular vagus nerve stimulation (taVNS) improves motor and non-motor symptoms in Parkinson's disease compared with sham.
Study Summary
• Significant improvements vs sham in quality of life (PDQ-39, p<0.001), sleep (PDSS-2, p<0.05), and autonomic function (SCOPA-AUT, p<0.01)
• Serum acetylcholine rose with taVNS and correlated with motor improvement (r=0.456, p=0.038); GluCEST showed decreased striatal/thalamic glutamate; DTI showed increased fractional anisotropy in left hippocampal cingulum and right ILF
• Well-tolerated: 20% taVNS vs 4.2% sham reported AEs (NS); all events mild-to-moderate (nausea, headache, diarrhea, mild skin pain); no SAEs
Intervention
Bilateral cymba conchae transcutaneous auricular vagus nerve stimulation (5 Hz, 500 μs, 30 min twice daily) for 3 weeks via home-based wearable device
Inclusion Criteria
Age ≥18, PD diagnosis (UK PD Brain Bank), Hoehn-Yahr 1-3, stable PD medications ≥30 days, willing to sign consent
Study Design
Arms: Single-blind, sham-controlled RCT — taVNS at bilateral cymba conchae vs sham at inner arm; both 30 min twice daily × 3 weeks
Patients per Arm: taVNS 25 (21 completers), Sham 24 (20 completers)
Outcome
• Secondary: PDQ-39 (p<0.001), PDSS-2 (p<0.05), SCOPA-AUT (p<0.01) all favored taVNS; no significant between-group effect on anxiety, depression, constipation, fatigue, cognition
• Biomarkers: serum ACh ↑ (correlated with motor benefit), striatal/thalamic glutamate ↓
• Safety: AEs 20% vs 4.2% (NS); no SAEs
Clinical Question
Does 3 weeks of home-based, twice-daily bilateral cymba conchae taVNS improve motor and non-motor symptoms in Parkinson's disease compared with sham?
Bottom Line
Home-based bilateral taVNS reduced MDS-UPDRS-III by 6.10 points and significantly improved quality of life, sleep, and autonomic function vs sham over 3 weeks, with elevated serum acetylcholine and reduced central glutamate as putative mechanisms; well-tolerated with no serious adverse events.
Major Points
- First randomized sham-controlled trial of home-based wearable taVNS in PD showing a clinically meaningful MDS-UPDRS-III reduction of 6.10 ± 4.29 points (exceeds MCID of 3.25)
- Significant secondary benefits in quality of life (PDQ-39), sleep (PDSS-2), and autonomic function (SCOPA-AUT) but not in mood, fatigue, or cognition
- Biomarker support: serum acetylcholine rose and correlated with motor improvement (r=0.456, p=0.038); GluCEST showed decreased striatal and thalamic glutamate; DTI revealed increased FA in left hippocampal cingulum and right inferior longitudinal fasciculus
- Favorable tolerability: AEs 20% (5/25) on taVNS vs 4.2% (1/24) on sham (NS); only 2 taVNS withdrawals (headache, diarrhea); no SAEs
- Registered as ChiCTR2300070828; single-center Chinese study calls for confirmation in independent populations
Study Design
- Study Type
- Randomized, single-blind, sham-controlled clinical trial
- Randomization
- Yes
- Blinding
- Single-blind (participants and outcome assessors blinded; principal investigator unblinded)
- Sample Size
- 49
- Follow-up
- 3 weeks (no long-term follow-up)
- Centers
- 1
- Countries
- China
Primary Outcome
Definition: Change in MDS-UPDRS-III from baseline to 3 weeks in OFF state
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| - | - | - | - |
Limitations & Criticisms
- Short follow-up (3 weeks only) — long-term efficacy and durability unknown
- Small sample (n=41 completers) and single-center design limit generalizability
- Single-blind rather than double-blind (PI aware of group assignment)
- Stimulation intensity individually adjusted but not systematically recorded, precluding dose-response analysis
- GluCEST, BOLD-fMRI, and serum acetylcholine are not validated PD therapeutic biomarkers — mechanistic findings remain exploratory
- Sham site at inner arm rather than a more anatomically matched control
- No significant between-group effect on anxiety, depression, constipation, fatigue, or cognition
- Exclusively Chinese single-center population — external validity uncertain
Citation
Neurotherapeutics. 2026 Jan 17;e00832. DOI:10.1016/j.neurot.2026.e00832