Insomnia, Sleep Disturbances, Stress
Conditions
Keywords
Transcutaneous Vagus Nerve Stimulation, sleep quality, Auricular Stimulation, university students
Brief summary
This study aims to evaluate the efficacy, safety, and feasibility of a home-based auricular transcutaneous vagus nerve stimulation (tVNS) program in Health Sciences university students with poor sleep quality. Participants will be randomly assigned (1:1) to receive either active auricular stimulation (cymba conchae/tragus) or a control stimulation applied to the earlobe. The intervention will be self-administered at home using a low-frequency TENS-like device for 60 minutes per session, 5 sessions per week for 3 weeks. Sleep quality will be primarily assessed using the Pittsburgh Sleep Quality Index (PSQI) before and after the intervention. Secondary outcomes include insomnia severity, daytime sleepiness, perceived stress, anxiety, quality of life, and psycho-academic outcomes.
Detailed description
Sleep disturbances are highly prevalent among university students and are frequently associated with academic stress and impaired psycho-academic functioning. Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive neuromodulation approach with potential to modulate autonomic function and stress responses, which may contribute to improvements in sleep quality. This study is designed as a randomized controlled pilot trial to assess the efficacy, safety, and feasibility of a home-based auricular tVNS intervention in Health Sciences university students. Eligible participants will be aged 18-35 years and will present poor sleep quality (PSQI \> 7) and primary insomnia criteria. Participants will be recruited from two academic centers (University of Malaga and Centro Universitario San Isidoro, affiliated with Pablo de Olavide University, Seville) and will be randomly allocated (1:1) to one of two arms: (1) active auricular stimulation targeting the left cymba conchae (with tragus as an alternative if needed), or (2) control (sham) stimulation delivered to the ipsilateral earlobe. Randomization will be performed using block randomization, and outcome assessors and data analysts will remain blinded to group assignment. The intervention will be delivered at home using a low-frequency TENS-like device with biphasic symmetrical waveform (25 Hz, 200 μs pulse width), administered for 60 minutes per session, 5 sessions per week for 3 weeks. Stimulation intensity will be individually adjusted to achieve a clear but comfortable paresthetic sensation below the pain threshold. Adherence will be monitored using an electronic diary with time stamps and daily photographic verification of electrode placement. The primary outcome is sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI) pre- and post-intervention. Secondary outcomes include insomnia severity (ISI), daytime sleepiness (ESS), perceived stress (PSS-14), anxiety measures (e.g., BAI and HAMA), depressive symptoms (HAMD), fatigue (FFS), and health-related quality of life (SF-12 v2). Psycho-academic outcomes will be measured using self-reported GPA and credits passed at the end of the semester. Safety will be assessed through systematic recording of adverse events throughout the intervention period.
Interventions
DEVICEAuricular Transcutaneous Vagus Nerve Stimulation (tVNS)
Home-based auricular transcutaneous vagus nerve stimulation (tVNS) delivered using a low-frequency TENS-like device. Stimulation is applied to the left cymba conchae (or tragus if needed) for 60 minutes per session, 5 sessions per week for 3 weeks. Biphasic symmetrical waveform (25 Hz, 200 μs pulse width). Intensity is individually adjusted to a strong but comfortable paresthesia below pain threshold.
DEVICESham stimulation
Control stimulation delivered using the same low-frequency TENS-like device and parameters (25 Hz, 200 μs) applied to the ipsilateral earlobe to mimic sensory stimulation. Sessions are performed for 60 minutes per session, 5 sessions per week for 3 weeks, without targeting auricular vagal afferents.
Sponsors
University of Malaga
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Participants are blinded to group allocation. Outcome assessors and data analysts are blinded to treatment assignment. The control condition consists of stimulation applied to the earlobe to mimic sensory stimulation without active auricular vagal stimulation.
Intervention model description
Randomized, controlled, two-arm, parallel-group pilot trial (1:1 allocation).
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
* Aged 18 to 35 years. * Undergraduate student enrolled in a Health Sciences degree program. * Poor sleep quality defined as PSQI \> 7. * Meets diagnostic criteria for primary insomnia according to ICSD-3. * Ability to understand study procedures and provide written informed consent. * Willing and able to self-administer the intervention at home and complete study questionnaires.
Exclusion criteria
* Current severe psychiatric disorder or ongoing psychotherapy treatment. * Neurological disorders (e.g., epilepsy). * Cardiac arrhythmias or implanted cardiac devices (e.g., pacemaker). * Current use of medications that significantly affect sleep (e.g., hypnotics or anxiolytics), unless stable and approved by the investigator. * Pregnancy. * Ear infection, skin lesions, or dermatologic condition preventing electrode placement. * Hypersensitivity or intolerance to electrical stimulation. * Participation in another clinical trial within the last 30 days.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sleep Quality (Pittsburgh Sleep Quality Index, PSQI) | Baseline and end of week 3 | PSQI total score (0-21). Higher scores indicate worse sleep quality. |
| Anxiety Symptoms (Beck Anxiety Inventory, BAI) | Baseline and end of week 3 | BAI total score. Higher scores indicate greater anxiety symptoms. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Insomnia Severity (Insomnia Severity Index, ISI) | Baseline and end of week 3 | ISI total score. Higher scores indicate greater insomnia severity. |
| Daytime Sleepiness (Epworth Sleepiness Scale, ESS) | Baseline and end of week 3 | ESS total score. Higher scores indicate greater daytime sleepiness. |
| Perceived Stress (Perceived Stress Scale-14, PSS-14) | Baseline and end of week 3 | PSS-14 total score. Higher scores indicate greater perceived stress. |
| Quality of Life (12-Item Short Form Survey, SF-12 v2) | Baseline and end of week 3 | SF-12 v2 component summary scores (physical and mental). Higher scores indicate better health-related quality of life. |
| Academic Performance (GPA and Credits Passed) | Baseline and end of semester (up to 16 weeks) | Self-reported grade point average (GPA) and number of credits passed during the academic term. |
Contacts
CONTACTIsmael Romero Garcia, Principal Investigator
Outcome results
None listed