Effect of Transcutaneous Auricular Vagal Nerve Stimulation on Chronic Constipation

Study Overview
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Brief Summary
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The worldwide prevalence of chronic constipation (CC) is 15%, and women are more likely to develop the disease than men. CC have a significant impact on quality of life and increase the burden of national health insurance. The conventional medication treatments are primarily symptom-specific and have limited efficacy. Previous small sample study had shown the therapeutic potential of transcutaneous auricular vagus nerve stimulation (taVNS) for irritable bowel syndrome with constipation (IBS-C). The aim of this study was to investigate whether taVNS could improve defecation condition and constipation symptoms in patients with CC.

Official Title
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Effect of Transcutaneous Auricular Vagal Nerve Stimulation on Chronic Constipation: A Randomized Controlled Trial

Conditions
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Chronic Constipation

Intervention / Treatment
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* Device: taVNS
* Drug: Laxative Agent


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: FC or IBS-C patients aged 18-75 years who meet the diagnostic criteria for Rome IV; Complete spontaneous bowel movements (CSBMs) per week < 3; No constipation medication used for at least 2 weeks prior to enrollment, not participated in clinical trials in the past three months, and no abnormal colonoscopy within the past 12 months in those with alarm symptoms. Exclusion Criteria: Have cognitive impairment, psychiatric disorders, or conditions that may affect patient cooperation; Have a cardiac pacemaker implantation or other electronically implanted devices; Prior taVNS treatment; History of colorectal surgery, except for simple appendectomy; Severe cardiovascular, hepatic, or renal disease; Known malignancy; Secondary constipation caused by medications and other diseases; Pregnant or lactating women; Refusal to sign an informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment group<br>patients will receive taVNS at left tragus for four weeks. | Device: taVNS<br>* Patients will receive taVNS (device produced by Xi'an Bashui Health Technology Co., Ltd) thirty minutes twice a day in the morning and the night for four weeks (duty circle: 30s on periods and 30s off periods; frequency: 25 Hz; amplitude of 0-2 mA at the maximum level that the patient could tolerate; pulse width: 0.5ms)<br>Drug: Laxative Agent<br>* Bisacodyl or glycerin enemas can be used in patients who do not have a bowel movement for more than 3 days.<br>|
| Sham Comparator: Sham-treatment group<br>patients will receive sham-taVNS at left earlobe for four weeks. | Device: taVNS<br>* Patients will receive taVNS (device produced by Xi'an Bashui Health Technology Co., Ltd) thirty minutes twice a day in the morning and the night for four weeks (duty circle: 30s on periods and 30s off periods; frequency: 25 Hz; amplitude of 0-2 mA at the maximum level that the patient could tolerate; pulse width: 0.5ms)<br>Drug: Laxative Agent<br>* Bisacodyl or glycerin enemas can be used in patients who do not have a bowel movement for more than 3 days.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Responder rate | Proportion of patients with an average of 3 or more complete spontaneous bowel movements (CSBMs) per week from 1 to 4 weeks | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Responder rate at the time of the follow-up visit | Proportion of patients with an average of 3 or more CSBMs per week from 5 to 12 weeks | 8 weeks | 
| CSBMs | Changes from baseline by time point in the CSBMs | 12 weeks | 
| Spontaneous bowel movements (SBMs) | Changes from baseline by time point in the SBMs | 12 weeks | 
| Abdominal symptoms | Changes from baseline by time point in abdominal symptoms scores (abdominal bloating, abdominal fullness, abdominal discomfort, abdominal pain, abdominal cramping). | 12 weeks | 
| Bristol stool form scale (BFSF) | Changes from baseline by time point in the BFSF | 12 weeks | 
| Laxative agents using | Proportion of patients using laxative agents and/or other adjunctive bowel measures at 1-12 weeks and the average number of times per week | 12 weeks | 
| Patient Assessment of Constipation symptom (PAC-SYM) | Changes from baseline by time point in the PAC-SYM score | 12 weeks | 
| Patient Assessment of Constipation Quality of Life questionnaire (PAC-QOL) | Changes from baseline by time point in the PAC-QOL score | 12 weeks | 
| Self-Rating Depression Scale (SDS) | Changes from baseline by time point in SDS scores | 12 weeks | 
| Self-Rating Anxiety Scale (SAS) | Changes from baseline by time point in SAS scores | 12 weeks | 
| Adverse events | Adverse events | 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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constipation