153 Endocrine and Metabolic Alterations following Deep Brain Stimulation in Anorexia Nervosa Table 3. Fatty acids in AN patients at four time points during follow-up. T-1 (Screening) T2 T3 T4 F-value P-value Reference range Fatty acids Free fatty acids (mmol/L) 0∙50 ± 0∙13 0∙41 ± 0∙13 0∙44 ± 0∙13 0∙57 ± 0∙13 0∙532 0∙672 0.14 – 0.44 mmol/L Chain-length index 17∙73 ± 0∙04 17∙56 ± 0∙17 18∙83 ± 1∙16 17∙74 ± 0∙03 0∙646 0∙630 Unsaturation index 1∙19 ± 0∙03 1∙22 ± 0∙03 1∙20 ± 0∙02 1∙23 ± 0∙04 0∙221 0∙878 Peroxidation index 0∙65 ± 0∙05 0∙69 ± 0∙05 0∙66 ± 0∙05 0∙71 ± 0∙05 3∙022 0∙087 AA/EPA ratio 15∙40 ± 5∙09 18∙67 ± 5∙09 17∙99 ± 5∙09 21∙20 ± 5∙09 0∙402 0∙755 DHA 104∙60 ± 46∙51 102∙85 ± 36∙50 91∙53 ± 24∙60 122∙18 ± 45∙67 0∙905 0∙513 DISCUSSION As part of a pilot study on the efficacy of vALIC DBS in AN, we found a significant decrease in the levels of testosterone and cortisol over time during treatment and non-significant changes on other axes. In AN, many endocrine and metabolic parameters are altered, either associated with the acute and chronic state of malnutrition, or the etiopathophysiology of AN, or both. In the following paragraphs we will discuss the changes we found after DBS per hormonal axis. Hypothalamic-pituitary-gonadal axis In our study we did not find significant changes in LH and FSH levels. Though a correlation between weight gain and changes in endocrine parameters was not possible in this small sample size, literature shows that amenorrhea persists in up to 15% of women despite weight recovery (21). It remains unclear whether this is due to persistent eating disorder pathology, atrophy of gonadotrophic cells or other factors like persisting low levels of leptine (22) . We did not find significant changes in estradiol levels over time. However, when looking at the individual changes in estradiol levels over time, we see a remarkable increase in estradiol levels (189.62%) at the end of the study in subject 2 (see supplement 2). This subject showed a significant increase in BMI after DBS, potentially suggesting a normalization of the HPG axis with weight restoration. It has to be notes that the follicular phase of the subjects at the measurementpoint was not known due to their postmenopausal and amenorrhoeic state. The observed significant decrease of testosterone levels over time seems contradictory to the fact that androgen concentrations in AN tend to be low. This decrease seemed irrespective of weight change. Low androgen levels may be a consequence of hypothalamic dysfunction and depletion of fat mass in AN. Miller e.a. (2009) found that low androgen levels in AN might contribute to anxiety, depression and eating disordered thinking and behavior in AN (23). Another
RkJQdWJsaXNoZXIy MjY0ODMw