Lower leptin level at discharge in acute anorexia nervosa is associated with early weight-loss

Anorexia-Induced Hypoleptinemia Drives Adaptations in the JAK2/STAT3 Pathway in the Ventral and Dorsal Hippocampus of Female Rats

Leptin is an appetite-regulating adipokine that is reduced in patients with anorexia nervosa (AN), a psychiatric disorder characterized by self-imposed starvation, and has been linked to hyperactivity, a hallmark of AN. However, it remains unknown how leptin receptor (LepR) and its JAK2-STAT3 downstream pathway in extrahypothalamic brain areas, such as the dorsal (dHip) and ventral (vHip) hippocampus, crucial for spatial memory and emotion regulation, may contribute to the maintenance of AN behaviors. Taking advantage of the activity-based anorexia (ABA) model (i.e., the combination of food restriction and physical activity), we observed reduced leptin plasma levels in adolescent female ABA rats at the acute phase of the disorder [post-natal day (PND) 42], while the levels increased over control levels following a 7-day recovery period (PND49). The analysis of the intracellular leptin pathway revealed that ABA rats showed an overall decrease of the LepR/JAK2/STAT3 signaling in dHip at both time points, while in vHip we observed a transition from hypo- (PND42) to hyperactivation (PND49) of the pathway. These changes might add knowledge on starvation-induced fluctuations in leptin levels and in hippocampal leptin signaling as initial drivers of the transition from adaptative mechanisms to starvation toward the maintenance of aberrant behaviors typical of AN patients, such as perpetuating restraint over eating.

Predictors of Treatment Outcome in Eating Disorders: A Roadmap to Inform Future Research Efforts

PURPOSE OF REVIEW

With the current review, we provide a brief summary of recent literature that tests clinically observable characteristics at baseline that may impact treatment response, across eating disorder diagnoses. We then provide a critical discussion regarding how researchers may shift their approach to this research to improve treatment implications and generalizability of these findings.

RECENT FINDINGS

Recent work has broadly replicated prior findings suggesting a negative impact of lower weight status, poor emotion regulation, and early-life trauma on eating disorder treatment outcomes. Findings are more mixed for the relative contributions of illness duration, psychiatric comorbidity, and baseline symptom severity. Recent studies have begun to explore more specific domains of previously tested predictors (e.g., specific comorbidities) as well as previously neglected identity-related and systemic factors. However, recent research continues to use similar sampling techniques and approaches to analysis used in prior work. We propose that resolving remaining questions and illuminating predictors of treatment outcome in eating disorders requires a new approach to research sampling and study design. Suggested changes that can be applied within a traditional clinical trial framework may yield new insights with relevance across transdiagnostic eating disorder presentations.

Predictors of relapse in eating disorders: A meta-analysis

INTRODUCTION

Eating disorders (EDs) have high rates of relapse. However, it is still not clear which factors are the strongest predictors of ED relapse, and the extent to which predictors of relapse may vary due to study and individual differences.

OBJECTIVE

We conducted a meta-analysis to quantify and compare which factors predict relapse in EDs and evaluate various potential moderators of these relations (e.g., ED subtype, sample age, length of follow-up, timing of predictor assessment, relapse operationalization).

METHODS

A total of 35 papers (effects = 315) were included. We used a multilevel random-effects model to estimate summary study-level effect sizes, and multilevel mixed-effects models to examine moderator effects.

RESULTS

Higher level of care, having psychiatric comorbidity, and higher severity of ED psychopathology were associated with higher odds of relapse. Higher leptin, higher meal energy density/variety, higher motivation for change, higher body mass index/weight/body fat, better response to treatment, anorexia nervosa-restricting (vs. anorexia nervosa-binge purge) subtype diagnosis, and older age of ED onset were associated with lower odds of relapse. Several moderators were identified.

DISCUSSION

A variety of variables can predict ED relapse. Furthermore, predictors of ED relapse vary among ED subtypes, sample ages, lengths of follow-up, timing of predictor assessments, and relapse operationalization. Future research should identify the mechanisms by which these variables may contribute to relapse.

Dehydroepiandrosterone sulfate levels predict weight gain in women with anorexia nervosa

OBJECTIVE

Anorexia nervosa (AN) is a serious condition characterized by undernutrition, complicated by endocrine dysregulation, and with few predictors of recovery. Urinary free cortisol (UFC) is a predictor of weight gain, but 24-h urine samples are challenging to collect. We hypothesized that serum dehydroepiandrosterone sulfate (DHEAS), which like cortisol is regulated by adrenocorticotropic hormone (ACTH), would predict weight gain and increases in fat mass in women with AN.

METHODS

We prospectively studied 34 women with AN and atypical AN, mean age 27.4 ± 7.7 years (mean ± SD), who received placebo in a 6-month randomized trial. Baseline DHEAS and 24-h UFC were measured by liquid chromatography with tandem mass spectrometry. Body composition was assessed at baseline and 6 months by DXA and cross-sectional abdominal CT at L4.

RESULTS

Mean baseline DHEAS level was 173 ± 70 μg/dl (0.7 ± 0.3 times the mean normal range for age) and mean baseline UFC (n = 15) was 20 ± 18 μg/24 h (normal: 0-50 μg/24 h). Higher DHEAS levels predicted weight gain over 6 months (r = 0.61, p < .001). DHEAS levels also predicted increases in fat mass (r = 0.40, p = .03), appendicular lean mass (r = 0.38, p = .04), and abdominal adipose tissue (r = 0.60, p < .001). All associations remained significant after controlling for age, baseline BMI, OCP use, duration of AN, and SSRI/SNRI use. DHEAS levels correlated with UFC (r = 0.61, p = .02).

DISCUSSION

In women with AN, higher serum DHEAS predicts weight gain and increases in fat and muscle mass. Additional studies are needed to confirm these findings and further elucidate the association between DHEAS and weight gain.

PUBLIC SIGNIFICANCE

Anorexia nervosa is a severe psychiatric condition, and predictors of weight recovery are needed to improve prognostication and guide therapeutic decision making. While urinary cortisol is a predictor of weight gain, 24-h urine collections are challenging to obtain. Like cortisol, dehydroepiandrosterone sulfate (DHEAS) is a hormone produced by the adrenal glands. As a readily available blood test, DHEAS holds promise as more practical biomarker of weight gain in anorexia nervosa.

BMI at Discharge from Treatment Predicts Relapse in Anorexia Nervosa: A Systematic Scoping Review

Background: Anorexia nervosa (AN) has high rates of enduring disease and mortality. Currently, there is insufficient knowledge on the predictors of relapse after weight normalization and this is why a systematic literature review was performed. Methods: PubMed, EMBASE, PsychInfo, and Cochrane databases were searched for literature published until 13 July 2021. All study designs were eligible for inclusion if they focused on predictors of relapse after weight normalization in AN. Individual study definitions of relapse were used, and in general, this was either a drop in BMI and/or reccurrence of AN symptoms. Results: The database search identified 11,507 publications, leaving 9511 publications after the removal of duplicates and after a review of abstracts and titles; 191 were selected for full-text review. Nineteen publications met the criteria and included 1398 AN patients and 39 healthy controls (HC) from adults and adolescents (ages range 11–73 years). The majority used a prospective observational study design (12 studies), a few used a retrospective observational design (6 studies), and only one was a non-randomized control trial (NRCT). Sample sizes ranged from 16 to 191 participants. BMI or measures of body fat and leptin levels at discharge were the strongest predictors of relapse with an approximate relapse rate of 50% at 12 months. Other predictors included signs of eating disorder psychopathology at discharge. Conclusions: BMI at the end of treatment is a predictor of relapse in AN, which is why treatment should target a BMI well above 20. Together with the time to relapse, these outcomes are important to include in the evaluation of current and novel treatments in AN and for benchmarking.

Exploring the Mechanisms of Recovery in Anorexia Nervosa through a Translational Approach: From Original Ecological Measurements in Human to Brain Tissue Analyses in Mice

Anorexia nervosa (AN) is a severe eating disorder where caloric restriction, excessive physical activity and metabolic alterations lead to life-threatening situations. Despite weight restoration after treatment, a significant part of patients experience relapses. In this translational study, we combined clinical and preclinical approaches. We describe preliminary data about the effect of weight gain on the symptomatology of patients suffering from acute AN (n = 225) and partially recovered (n = 41). We measured more precisely physical activity with continuous cardiac monitoring in a sub-group (n = 68). Using a mouse model, we investigated whether a long-term food restriction followed by nutritional recovery associated or not with physical activity may differentially impact peripheral and central homeostatic regulation. We assessed the plasma concentration of acyl ghrelin, desacyl ghrelin and leptin and the mRNA expression of hypothalamic neuropeptides and their receptors. Our data show an effect of undernutrition history on the level of physical activity in AN. The preclinical model supports an important role of physical activity in the recovery process and points out the leptin system as one factor that can drive a reliable restoration of metabolic variables through the hypothalamic regulation of neuropeptides involved in feeding behavior.