Investigation of the efficiency of auricular vagus nerve stimulating in patients with female fibromyalgia

Transcutaneous auricular vagus nerve stimulation (TAVSS) is a non-surgical method that stimulates auricular branch of vagus with surface electrodes from concha and/or tragus. The aim of this study is to examine effect of TAVSS on pain, depression, anxiety, functionality and limitations, and autonomic function in fibromyalgia syndrome (FMS). Forty female patients aged 18-45 years with FMS were divided into two groups and TAVSS was applied to the left ear in Group 1 and bilateral ear in Group 2 for 11 sessions. Visual Analogue Scale (VAS), Beck Depression Inventory (BDI), Fibromyalgia Impact Questionnaire (FIQ) and Beck Anxiety Inventory (BAI) were used. Autonomic nervous system activity was measured with PNS and SNS index. There was no significant difference between groups in the VAS, BDI, FIQ and BAI questionnaires in 1st day pre-session, 14th day post-session and 28-30th day control measurements (p>0.05). There was no statistical difference between left ear TAVSS application compared to bilateral application, and positive effects were observed in complaints such as pain, functional status, fatigue, anxiety and depression in both groups. Parasympathetic activity increased while sympathetic activity decreased in the control measurements on the 1st day before and after the session, on the 14th day before and after the session, and on the 28-30th day. While there was no significant difference between the groups, TAVSS gave positive results in the clinical symptoms of FMS in both groups. There is a need for studies with longer follow-ups and more cases that examine the mechanisms of action of TAVSS in FMS. Key Words: Pain, Depression, Anxiety, Functional status, Autonomic nervous system activity