57 Deep Brain Stimulation of the Ventral Anterior Limb of the Capsula Interna in Patients with Chronic Treatment-Refractory Anorexia Nervosa somatic state. However, when asked, all patients report a subjective improvement of their overall psychological state and quality of life. One patient successfully started schema therapy after her participation in the study, grasping on subjects that were not accessible for her before. Another subject achieved to become an experience expert conducting training sessions for other patients through professional organizations. The majority of the patients report a decrease in the satisfactory aspects of the eating disorder behavior, meaning that this behavior, although sustained, lost its rewarding properties, leaving the more room for other, healthier behavior. All subjects state that they would undergo the whole process again if needed, because of the overall positive effects on their mood and life. DISCUSSION To the best of our knowledge, this is the first study of vALIC DBS in AN. By applying an extensive optimization period with throughout phenotyping, we provide detailed insight in the psychological, somatic and functional effects. We demonstrated that vALIC DBS can be an effective and relatively safe new target for chronic, treatment-refractory AN. The mean baseline BMI of our patents was extremely low (categorized as ‘very severe’ in the DSM-5), which on average improved at one year postoperatively to the DSM-5 category ‘mild’. As can be seen in figure 2, the increase in BMI was primarily seen in two of four patients. The other two subjects showed only a mild increase in BMI. The response rate is comparable to other major studies in this field; Liu et al., 2020 (14) and Lipsman et al., 2017 (12), reported a 61% and 57% response rate respectively. Other clinically important physical improvements (SBP, DBP and T) likely reflect a direct consequence of the weight restoration (36, 37). The improvement was also seen clinically, in a decrease in eating-related behavior like purging and caloric and body checking. One of the patients, who was using laxatives in extremely high amounts (bisacodyl 10 mg, 100-150 tablets per day) before DBS, succeeded in completely quitting the use of laxatives. The improvement in our patients was also seen in the psychological outcomes. The YBC-EDS showed an overall improvement compared to baseline. Two out of four patients could be formally categorized as responders (≥35% decrease). All patients reported a decrease in preoccupations and rituals, because they experienced them as less rewarding. Similar response was reported in Lipsman et al., 2017 (12). The other questionnaires supported the improvements, with a substantial and significant decrease in mean depression and anxiety symptoms. This corresponds to effects of vALIC DBS in other disorders. Also given the high comorbidity rates, these outcomes are of great clinical importance in AN (38).
RkJQdWJsaXNoZXIy MjY0ODMw