Figure 5.

Effect of vagus nerve stimulation (VNS) during 6 months of follow-up in the seven patients presenting with an active Crohn’s disease at inclusion on (A) the Crohn’s disease activity index (CDAI); (B) C-reactive protein (CRP); (C) the Crohn’s disease endoscopic index of severity (CDEIS); (D) the vagal tone (high frequency in normalized units [HFnu]) and the sympathovagal balance (low frequency [LF]/high frequency [HF]). CDAI < 150, clinical remission. Cut-off level for CRP, 5 mg/L. CDEIS < 6, endoscopic remission. HFnu, homeostatic range. Balanced ratio of LF/HF (sympathovagal balance) ∼1. (From Bonaz et al. 2016a; modified, with permission, from the author.)