Left-sided ear-based vagus nerve stimulation leads to a reduction in symptom severity in fibromyalgia patients and influences the immune system and neuroplasticity.
The experiment was conducted in a randomized, double-blind, sham-controlled trial format, including 51 women diagnosed as fibromyalgia sufferers. The participants were split into three groups: sham, right-sided auricular vagus nerve stimulation, or left-sided auricular vagus nerve stimulation. Over a period of four weeks, these women partook in weekly sessions and were surveilled for 12 weeks. The intensity of pain was the main outcome measured, along with various secondary outcomes such as psychological symptoms, sleep, functional status, quality of life, and specific circulating biomarkers.
Although there wasn't a significant difference in pain intensity between the groups, the left-sided stimulation had a significant and modest reduction in overall symptom severity. The left-sided stimulation also had consistent effects on the immune system, reducing some inflammatory markers and increasing anti-inflammatory and neuroplasticity marker concentrations. However, these clinical pain relief effects were not superior to the control group, showing that this approach might be more useful for its immunity effect and neuroplasticity influence.
