Copeptin in anorexia nervosa

Abstract

Objective Antidiuretic hormone (ADH) is involved in the response to stress and in depression and anxiety. However, studies on ADH in anorexia nervosa (AN) show conflicting results. A major reason for this may be methodological challenges due to short half‐life of ADH in circulation and rapid degradation in vitro. To overcome these obstacles, copeptin, the C‐terminal fragment stemming from the ADH precursor, has been increasingly used as a stable clinical measure for ADH. Furthermore, copeptin has been recognized as a biomarker of insulin resistance in obesity. Methods We measured fasting copeptin in plasma from 25 normohydrated, stable women with AN (BMI 13.0 ± 2.0) and 25 age‐matched women. Results No difference in copeptin levels was found (6.8 ± 1.8 vs. 5.5 ± 0.5 pmol/L). Confirmatory, copeptin concentrations were correlated to insulin resistance assessed by the homeostasis model assessment of insulin resistance. Discussion We report for the first time that copeptin level as a marker of ADH activity is not altered in fluid‐ and electrolyte‐stabilized patients with severe AN patients, indicating that ADH may not be crucial in the pathophysiological involvement of psychologic stress in AN.

RETRACTED ARTICLE: Review novel insights into the diagnostic and prognostic function of copeptin in daily clinical practice

“…Results obtained from a study made to compare serum copeptin concentrations in 25 normo-hydrated stable women with anorexia nervosa and 25 age-matched women as control group were unexpected. Where there was no noticeable change in serum copeptin concentrations between the two groups, which gives indication that anti-diuretic hormone may not be critical for the pathophysiological implication of psychological stress in cases of anorexia nervosa [65]. The probability of using copeptin as a biomarker of response to anti-depressant treatment in major depressive disorder was indicated in a pilot study [66].…”

Copeptin and Stress

“…Copeptin levels following standardized assessment of psychological stress by using the Trier Social Stress Test were determined in healthy volunteers, showing a significant increase from baseline to the immediate post-test period (3.7→5.1 pmol/L in Siegenthaler's cohort [131], about +30% within 20 min in Spanakis's cohort [132], >2-fold increase within 15 min in Bae's cohort [133]) which was mainly related to feelings of tension and avoidance [131] and consistent with the increase in cortisol levels [131,132], although with a gender difference favoring males [132] and a weaker association with state anxiety and heart rate than salivary cortisone [133]. Surprisingly, data from a small observational study indicate copeptin seems not to account for psychological stress, anxiety and depression in women with fluid-and electrolyte-corrected severe anorexia nervosa [134], although an association between all the aforementioned disturbances and the chronic hyperactivation of HPA axis in anorexia nervosa was widely and consistently reported [135].…”

Renal fluid and acid/base balance during refeeding in restrictive eating disorders

“…Recent data support the concept that arginine vasopressin is not commonly dysregulated in anorexia nervosa. Indeed, copeptin levels—which are stable markers of vasopressin activity—are similar in fluid‐ and electrolyte‐stabilized patients with severe anorexia nervosa compared to healthy controls (Goetze & Stoving, 2020). In addition, as demonstrated by declining serum creatinine concentrations and stabilizing hemodynamic parameters, renal fluid diuresis was not associated with intravascular volume depletion.…”

“…However, renal fluid losses have also been reported later in the course of refeeding (Kanbur & Katzman, 2011; Rosen et al, 2019). These have been postulated to be due to neuroendocrine dysregulation in the form of partial central diabetes insipidus (Kanbur & Katzman, 2011; Rosen et al, 2019); recent data call into question this theory, however, by demonstrating that vasopressin production is not dysregulated in the majority of patients with anorexia nervosa (Goetze & Stoving, 2020).…”