Major Depressive Disorder
Conditions
Keywords
Transcutaneous Vagus Nerve Stimulation, Cardiac autonomic function, Depressive symptomatology
Brief summary
This study will evaluate the short term effects of respiratory-gated transcutaneous vagus nerve stimulation on the regulation of cardiovagal activity, depressive symptomatology and immune function in subjects with major depression and determine the optimal stimulation frequency for this population.
Detailed description
This study will compare the acute effects of respiratory-gated transcutaneous vagus nerve stimulation (tVNS) at different stimulation frequencies and sham stimulation during five sessions within a 2 week period. Heart rate variability (HRV) point process adaptive filtering estimation algorithms will be used to evaluate changes in cardiac autonomic physiology in subjects with major depression in response to tVNS. The effects of tVNS on cardiovagal regulation will be evaluated at rest and in response to an emotion reactivity task. Depression rating scales (Beck's Depression Inventory) will be used to evaluate short term effects of tVNS on depressive symptoms in these subjects. In addition, the study will evaluate the acute effects of the stimulation on serum levels of pro-inflammatory cytokines. The stimulation frequency that produces the greatest regulatory effects on depressive symptoms and physiological variables in this population will be used in a second longitudinal phase of the study.
Interventions
respiratory-gated non-painful electrical stimulation of the auricle for 30 minutes
stimulation of the auricle for 30 minutes
Sponsors
Study design
Eligibility
Inclusion criteria
* Diagnosis of recurrent Major Depressive Disorder with a current active depressive episode * Currently not taking psychiatric medications or on a stable therapeutic dose of psychiatric medication for at least 30 days prior to entering the study
Exclusion criteria
* History of cardio-, cerebro-, or peripheral vascular disease, diabetes mellitus, morbid obesity (BMI \> 40 kg/m2), kidney or liver failure, history of unexplained fainting spells * Any psychiatric disorder involving a history of psychosis (e.g. schizophrenia, bipolar disorders, severe personality disorders) * Any chronic condition affecting movement, speech and/or ability to read or follow written instructions * Substance use disorder, either mild, moderate, or severe within the past 12 months (excludes nicotine) * History of suicide attempt within the last year or current active suicidal ideation * History of a clinically defined neurological disorder including, but not limited to: Any condition likely to be associated with increased intracranial pressure; space occupying brain lesion; History of cerebrovascular accident; Transient ischemic attack within two years; Cerebral aneurysm; Dementia; Parkinson's Disease; Huntington's chorea; or Multiple sclerosis. * Pregnant or nursing * Metallic implants or devices contraindicating tVNS
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cardiac autonomic function | 1 hour | Changes in cardiac autonomic function (High Frequency power-Heart Rate Variability) between active and sham tVNS. |
| Change in depressive symptoms assessed by the Beck Depression Inventory | 1 hour | Changes from baseline to post-stimulation in the score of the Beck Depression Inventory will be compared between active and sham tVNS. (Beck depression inventory minimum score= 0, maximum score= 63; higher total scores indicate more severe depressive symptoms) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in serum levels of pro-inflammatory cytokines | 2 hours | Changes in serum levels of proinflammatory cytokines (Interleukin 1B, Interleukin 6, Tumor necrosis factor alfa) from baseline to post-stimulation will be assessed and compared between active and sham tVNS |
Countries
United States