# Effects of Transcutaneous Auricular Vagus Nerve Stimulation on Posttraumatic Stress Disorder Symptoms in World Trade Center Responders: A Feasibility and Acceptability Study

## TL;DR

This study tests a non-invasive, home-based treatment for PTSD in 9/11 responders, showing it is feasible and acceptable with some symptom improvement.

## Contribution

The study introduces transcutaneous auricular vagus nerve stimulation (taVNS) as a feasible, non-invasive PTSD intervention for trauma-exposed populations.

## Key findings

- 90.6% retention and 80.23% adherence were achieved during eight weeks of daily at-home taVNS use.
- 40% of the active taVNS group showed a ≥10-point reduction in CAPS-5 scores, indicating symptom improvement.
- No significant differences were found in self-reported depression, anxiety, or sleep outcomes between groups.

## Abstract

Public health relevance—How does this work relate to a public health issue?
This study addresses the persistent PTSD treatment gap among 9/11 World Trade Center responders by testing a home-based, non-invasive intervention to reduce barriers to engagement.This randomized, double-blind trial evaluates taVNS specifically in clinician-confirmed PTSD, advancing neuromodulation beyond prior work and into a high-need public health cohort.

This study addresses the persistent PTSD treatment gap among 9/11 World Trade Center responders by testing a home-based, non-invasive intervention to reduce barriers to engagement.

This randomized, double-blind trial evaluates taVNS specifically in clinician-confirmed PTSD, advancing neuromodulation beyond prior work and into a high-need public health cohort.

Public health significance—Why is this work of significance to public health?
The trial demonstrates strong feasibility in a real-world responder population, with 90.6% retention and an average adherence of 80.23% during eight weeks of daily at-home use.The intervention highlights targeted clinical signals, most notably a significant improvement in CAPS-5 Cognition/Mood and ≥10-point CAPS-5 reductions in 40% of the active group, indicating potential symptom relief in domains tied to day-to-day functioning and quality of life.

The trial demonstrates strong feasibility in a real-world responder population, with 90.6% retention and an average adherence of 80.23% during eight weeks of daily at-home use.

The intervention highlights targeted clinical signals, most notably a significant improvement in CAPS-5 Cognition/Mood and ≥10-point CAPS-5 reductions in 40% of the active group, indicating potential symptom relief in domains tied to day-to-day functioning and quality of life.

Public health implications—What are the key implications or messages for practitioners, policy makers and/or researchers in public health?
Public health programs, such as the WTCHP, can pilot taVNS as a low-burden adjunct to evidence-based psychotherapies to improve treatment reach and adherence among trauma-exposed populations.Health systems can incorporate taVNS into stepped-care pathways as an acceptable, minimally risky option for patients unwilling or unable to engage in intensive psychotherapy, potentially increasing overall PTSD treatment uptake and reducing unmet need.

Public health programs, such as the WTCHP, can pilot taVNS as a low-burden adjunct to evidence-based psychotherapies to improve treatment reach and adherence among trauma-exposed populations.

Health systems can incorporate taVNS into stepped-care pathways as an acceptable, minimally risky option for patients unwilling or unable to engage in intensive psychotherapy, potentially increasing overall PTSD treatment uptake and reducing unmet need.

Background: Responders to the September 11, 2001, WTC attacks experience high rates of PTSD, and existing treatments often lead to high dropout and low care use. Objectives: This randomized, double-blind, sham-controlled trial assesses the feasibility and acceptability of transcutaneous auricular vagus nerve stimulation (taVNS) as a potential PTSD treatment for 9/11 responders. Methods: A total of 32 WTC responders aged 18+ with PTSD, recruited via the World Trade Center Health Program, participated; those with current psychosis, unstable medical conditions, or recent trial involvement were excluded. Participants were randomly assigned to taVNS or sham groups and asked to use the device for 15 min daily for 8 weeks, with staff and participants blinded. Primary outcomes included recruitment, adherence, retention, and feedback. Secondary outcomes examined changes in depression (PHQ-9), anxiety (GAD-7), and sleep (PSQI). Data were analyzed with mixed-effects models focusing on PTSD and mental health symptoms. Results: The taVNS group showed modest PTSD improvement, with a 10-point CAPS-5 reduction in 40% of stimulation participants versus 28.5% sham; no significant differences in self-reported symptoms were found. Discussion: Daily taVNS over eight weeks is feasible and acceptable, warranting larger studies to detect differences and identify subgroups with greater benefit. Trial registration: “taVNS to Reduce PTSD Symptoms in WTC Responders” (NCT05212714); registered 9 September 2021.