By Melinda Fontaine
At the 3rd World Congress on Abdominal and Pelvic Pain organized by the International Pelvic Pain Society, Professor Qasim Aziz spoke about Autonomic Dysregulation in Functional Gastrointestinal Disorders. Qasim Aziz, MBBS, FRCP, PhD is Professor of Neurogastroenterology at Barts and The London School of Medicine and Dentistry at Queen Mary, University of London. Professor Aziz taught us how the autonomic nervous system plays a role in chronic pain conditions and functional gastrointestinal disorders. This understanding has led to the use of new treatments that modulate the autonomic nervous system.
The autonomic nervous system is made up of the brain, the parasympathetic and sympathetic nervous systems, and the enteric (gut) nervous system. The autonomic nervous system works without us having to think about it, and helps with things like keeping our heart beating and digesting our food. The parasympathetic nervous system is affectionately called the “rest and digest” system because it is active when we are relaxed and helps with digestion. When you add stress to the equation, big changes occur. Stress can be in any form: deadlines, anxiety, drama, attack on your health, lack of sleep, not enough self care, etc. When stress is applied to the system, the peripheral nervous system releases neurotransmitters which dock on the immune cells and increase the inflammatory immune response through the vagus nerve.
Now if all that sounded like scientific mumbo-jumbo, the important piece to remember is “through the vagus nerve”. The vagus nerve is part of the parasympathetic “rest and digest” nervous system and innervates the heart, lungs, and digestive system.
A number of studies have been done on the role of the peripheral nervous system and vagus nerve. Decreased peripheral nervous system/vagus nerve activity has been found in patients with irritable bowel syndrome,1 functional dyspepsia,2 and delayed gastric emptying after meals.3 Could we increase the vagus nerve activity to eliminate these and other symptoms? Possibly! There are three treatments being explored to stimulate the vagus nerve and decrease pain and inflammation.
- Cognitive Behavioral Therapy increased vagus nerve/parasympathetic activity in patients with irritable bowel syndrome over the course of 24 weeks.4
- Deep Breathing increased vagus nerve/parasympathetic activity and decreased pain in the esophagus in response to acid.4
- Vagus Nerve Stimulation improved movement of food through the digestive system,5 reduced abdominal pain,6 and decreased inflammation.7
Cognitive Behavioral Therapy is a common method of psychotherapy and Deep Breathing has been around for ages, but Vagus Nerve Stimulation is new, and I would like to explain it a little here. For more information about how this idea relates to chronic pelvic pain, see Liz’s post about Dr. Chelimsky’s presentation.
Applying electrical current to the vagus nerve through an implantable or external device amplifies the signals sent through the nerve. The devices work by attaching electrodes to the vagus nerve either at the ear or the neck. Not all these devices are available in the United States, and they currently require a doctor’s prescription. These devices have also been studied for use on headaches, seizures, depression, fibromyalgia and chronic pelvic pain.8 These treatment are relatively new and are still being studied, but the research is promising.
Of course this information made me very excited about this new vagus nerve treatment idea. I want to run right out and get my hands on a stimulator. After some research, I learned that the FDA released the first non-invasive vagus stimulator in 2017, gammaCore. This device applies stimulation at the neck for the acute treatment of pain associated with episodic cluster headache in adult patients. It is available by physician prescription only, and the list price of gammaCore therapy is $575.00 per month.
Thus, for now I will have to use the treatment strategies most available to me. I like to remind patients that pelvic pain is rarely ever caused by one thing, so a multimodal approach that includes physical therapy is necessary. This research shows us how the parasympathetic nervous system needs to be considered in our treatment approach. I teach patients to breathe deeply during our sessions and encourage them to practice on their own. I use Nicole’s blog about diaphragmatic breathing to teach the technique. Sometimes I encourage patients to seek out psychotherapy, such as cognitive behavioral therapy, as a piece of their treatment. One day, I may also be able to recommend vagal nerve stimulation as part of a complete treatment approach.
We thank Professor Qasim Aziz for a fantastic lecture. Please click here to view his entire lecture.
- Liu Q, et al. Autonomic functioning in irritable bowel syndrome measured by heart rate variability: A meta-analysis. Journal of Digestive Diseases 2013; 14: 638-646
- Dal K, et al. Decreased parasympathetic activity in patients with functional dyspepsia. European Journal of Gastroenterology & Hepatology 2014, 26:748-752
- Guo WJ, et al. Impaired vagal activity to meal in patients with functional dyspepsia and delayed gastric emptying. J Int Med Res 300060517726442. 2017
- Botha C, Farmer A, et al. Preliminary report: modulation of parasympathetic nervous system tone influences oesophageal pain hypersensitivity. GUT 2015, 64:611-7
- Frokjaer JB, et al. Modulation of vagal tone enhances gastroduodenal motility and reduces somatic pain sensitivity. Neurogastroenterol Motil 2016; 28, 592-598
- Kovacic et al. Neurostimulation for abdominal pain-related functional gastrointestinal disorders in adolescents: a randomised, double-blind, sham-controlled trial. Lancet Gastroenterol Hepatol 2017; 2: 727-737
- Beckers AB, et al. Gastrointestinal disorders in joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type: a review for the gastroenterologist. Neurogastroenterol Motil 2017; 29: doi: 10.1111/nmo.13013. Epub 2017 Jan 13
- Chakravarthy, et al. Review of vagal nerve stimulation in use of chronic pain management. Current Pain and Headache Reports Journal 2015; 19:54