Uncoupling of cardiovascular risk markers in adolescent girls with anorexia nervosa

A transdiagnostic and diagnostic-specific approach on inflammatory biomarkers in eating disorders: A meta-analysis and systematic review

Eating disorders (EDs) are severe mental illnesses with a multifactorial etiology and a chronic course. Among the biological factors related to pathogenesis and maintenance of EDs, inflammation acquired growing scientific interest. This study aimed to assess the inflammatory profile of EDs, focusing on anorexia nervosa, bulimia nervosa, and including for the first time binge eating disorder. A comprehensive research of existing literature identified 51 eligible studies for meta-analysis, comparing levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), osteoprotegerin (OPG), soluble receptor activator of nuclear factor kappa-B ligand (sRANKL), interleukin-1β (IL-1β), and interleukin-10 (IL-10) between patients with EDs and healthy controls (HCs). The systematic review explored other inflammatory biomarkers of interest, which did not meet the meta-analysis criteria. Results revealed significantly elevated levels of TNF-α, OPG, sRANKL, and IL-1β in patients with EDs compared to HCs. Additionally, the results highlighted the heterogeneity of inflammatory state among patients with EDs, emphasizing the need for further research into the association between inflammatory biomarkers and psychopathological correlates. This approach should transcend categorical diagnoses, enabling more precise subcategorizations of patients. Overall, this study contributed to the understanding of the inflammatory pathways involved in EDs, emphasizing potential implications for diagnosis, staging, and targeted interventions.

Pro-inflammatory cytokine alterations in recent onset anorexia nervosa adolescent female patients before and after 6 months of integrated therapy: A case-control study

Anorexia nervosa (AN) is a complex disorder affecting mainly, but not only, teenagers. Researchers agree that AN is deeply associated with a pro-inflammatory state following an impaired immune system, resulting from altered levels of cytokines such as IL-1β and TNF-α, also impacted by the frequent depressive states. Thus, this case-control study aimed to evaluate the relationship between patients suffering from AN undergoing specialized eating disorder treatment for AN and pro-inflammatory cytokines. To reach our purpose, we assessed eating-related psychopathology and depressive symptoms and measured serum concentration of pro-inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α before and after 6 months of integrated therapy (which included psychopharmacotherapy, psychotherapy, and nutritional treatment), to define whether selected pro-inflammatory cytokines could be considered a pathophysiological marker of the disorder. A sample of 16 young female patients with early diagnosis of AN, and without any previous treatment, and 22 healthy controls matched by age, sex, and socioeconomic status were enrolled. After 6 months of integrated therapy, a significant decrease of all selected pro-inflammatory cytokines was detected. In addition, an improvement in the anxiety-depressant aspects was also noted. In conclusion, the results obtained suggest that pro-inflammatory cytokines are indeed related to the pathophysiology of AN. However, further investigations, involving larger samples of patients with distinct subtypes of AN, are essential to confirm the current findings.

A naturalistic study of plasma lipid alterations in female patients with anorexia nervosa before and after weight restoration treatment

BACKGROUND

Plasma lipid concentrations in patients with anorexia nervosa (AN) seem to be altered.

METHODS

We conducted a naturalistic study with 75 adult female patients with AN and 26 healthy female controls (HC). We measured plasma lipid profile, sex hormones and used self-report questionnaires at admission and discharge.

RESULTS

Total cholesterol (median (IQR): 4.9 (1.2)) and triglycerides (TG) (1.2 (0.8)) were elevated in AN at admission (BMI 15.3 (3.4)) compared with HC (4.3 (0.7), p = 0.003 and 0.9 (0.3), p = 0.006) and remained elevated at discharge (BMI 18.9 (2.9)) after weight restoration treatment. Estradiol (0.05 (0.1)) and testosterone (0.5 (0.7)) were lower in AN compared with HC (0.3 (0.3), p =  < 0.001 and 0.8 (0.5), p = 0.03) and remained low at discharge. There was no change in eating disorder symptoms. Depression symptoms decreased (33 (17) to 30.5 (19), (p = 0.007)). Regression analyses showed that illness duration was a predictor of TG, age was a predictor of total cholesterol and LDL, while educational attainment predicted LDL and TG.

CONCLUSION

Lipid concentrations remained elevated following weight restoration treatment, suggesting an underlying, premorbid dysregulation in the lipid metabolism in AN that persists following weight restoration. Elevated lipid concentrations may be present prior to illness onset in AN.

LEVEL OF EVIDENCE

III: Evidence obtained from well-designed cohort or case-control analytic studies.

Bioelectrical Impedance Vector Analysis, Nutritional Ultrasound®, and Handgrip Strength as Innovative Methods for Monitoring Critical Anorexia Nervosa Physical Recovery: A Pilot Study

Eating disorders (EDs) manifest as persistent disruptions in eating habits or related behaviors, significantly impacting physical health and psychosocial well-being. Nutritional assessment in ED patients is crucial for monitoring treatment efficacy. While dual-energy X-ray absorptiometry (DEXA) remains standard, interest in alternative methods such as bioelectrical impedance vector analysis (BIVA) and Nutritional Ultrasound® (NU) has risen due to their affordability and portability. Additionally, hand dynamometry offers a user-friendly approach to assessing grip strength (HGS), indicative of nutritional status. A prospective study was carried out to evaluate the utility of BIVA, NU®, and HGS in 43 female AN patients. Measurements were taken at baseline and hospital discharge. A total of 41 patients completed the study. After the intervention, numerous BIVA-related parameters such as fat (3.5 ± 2 kg vs. 5.3 ± 2.7 kg, p < 0.001) and free fat mass (33.9 ± 3.8 kg vs. 37.5 ± 4.1 kg, p < 0.001) were partially restored. Similarly, Nutritional Ultrasound® showed promising results in assessing body composition changes such as total abdominal fat tissue (0.5 ± 0.3 cm vs. 0.9 ± 0.3 cm, p < 0.05). In the same way, rectus femoris cross-sectional area values correlated with clinical outcomes such as free fat mass (0.883, p < 0.05) and appendicular muscle mass (0.965, p < 0.001). HGS reached the normality percentile after the intervention (21.6 ± 9.1 kg vs. 25.9 ± 12.3 kg, p < 0.05), demonstrating a significant association between grip strength and body composition parameters such as free fat mass (0.658, p < 0.001) and appendicular muscle mass (0.482, p < 0.001). Incorporating BIVA-, NU®-, and HGS-enhanced nutritional assessment into the treatment of AN patients offers cost-effective, portable, and non-invasive alternatives to DEXA. These techniques offer valuable insights into changes in body composition and nutritional status, which, in turn, facilitate treatment monitoring and contribute to improved patient outcomes.

PCSK9 and leptin plasma levels in anorexia nervosa

AIM

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a regulator of low-density-lipoprotein cholesterol (LDL-C), a major risk factor for cardiovascular (CV) disease. Since the hormone leptin has been suggested as having a role in CV risk regulation, possibly by modulating LDL receptor expression through the PCSK9 pathway, nutritional status may represent a potential regulator. Thus, evaluation of PCSK9 levels in human eating disorders appears to be of interest. In this report, we evaluate the lipoprotein profile, PCSK9, and leptin levels in subjects affected by anorexia nervosa (AN) to improve our understanding of the metabolic alterations in this disease.

METHODS AND RESULTS

We designed a case-control observational study, enrolling 20 anorexic adolescent females and 20 adolescent females without AN as the control group, age- and sex-matched. Subjects affected by AN showed lower BMI, total cholesterol, and LDL-C in comparison to the control group, with lipoprotein levels in the normal range. Furthermore, adolescent girls with AN show significantly higher PCSK9 (+24%, p < 0.005) and lower leptin levels (-43%, p < 0.01), compared to the control group.

CONCLUSIONS

The findings of increased levels of PCSK9 and reduced leptin levels among AN subjects warrant further research in order to unravel the role of the liver and adipose tissue in the management of PCSK9/LDL metabolism in adolescents affected by AN.

Anorexia Nervosa in vivo cytokine production: a systematic review

INTRODUCTION

The underlying psychobiology that contributes to Anorexia Nervosa (AN) onset and disease progression remains unclear. New research is emerging suggesting a possible link between inflammation and a variety of mental illnesses. Alterations of cytokines may play a role in the pathogenesis of AN. Some studies have found differences in the cytokine profile of those with AN compared to healthy controls, but results are heterogeneous. The aim of this work was to systematically review existing studies investigating in-vivo cytokine production in those with AN before and after weight restoration compared to controls.

METHODS

A comprehensive literature search of four electronic databases (PubMed, PsychInfo, EMBASE and CINAH) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines to identify human in-vivo studies investigating the relationship between AN and cytokine production. Data extracted from included studies related to population characteristics (e.g. age, gender, mean mBMI/%IBW), cytokine measurement and relevant findings. Confounding factors (e.g. smoking status, co-morbid mental illness, menstruation status) were also collected.

RESULTS

36 studies were eligible for this systematic review of which the majority were conducted in Europe (77.8%) and involved female subjects (97.2%). Those with AN ranged in age from 13 to 47 years and had an illness duration of 3 months to 24 years. 15 candidate cytokines and 3 receptors were identified (TNF-alpha, IL-6, IL-1B, CRP, IL-2, IL-7, IL-10, IFN-γ, TNF-R2, IL-1 α, IL-15, TNF-R1, IL-17, IL-18, TGF-B1, IL-12, IL-6R and TGF-B2) exploring in-vivo levels in patients with AN and comparing to controls. TNF-alpha and IL-6 were the most extensively studied with IL-6 being significantly elevated in 4 out of 8 (50%) of longitudinal studies when comparing AN patients at baseline compared to post weight restoration. Following weight restoration, there was no difference in IL-6 levels when comparing to HC in 7 of 8 (87.5%) longitudinal studies examined.

CONCLUSIONS

The most promising cytokine potentially involved in the pathogenesis of AN appears to be IL-6, and possibly TNF-alpha pathways. The heterogeneity of clinical and methodology factors impedes the generalizability of results. Future studies may wish to address these methodological shortcomings as alterations in cytokine levels in AN could act as therapeutic targets assisting with weight restoration and psychopathology and may offer diagnostic potential.

Controlling Behavior, Sex Bias and Coaching Success in Japanese Track and Field

Coaching athletes is a complex and lengthy process. Recently, attention has been given to coaches over-controlling behavior toward the athletes' personal lives and possible sex bias, but the impact of these behaviors on coaching success is unclear. An anonymous survey was answered by 412 track and field coaches (male: 369; female: 43), comprising questions regarding controlling behaviors, sex bias, and personal background. A Chi-square test and logistic regression were performed to determine the factors related to the coach's characteristics and their success in coaching athletes (to national vs. non-national level). The results showed that controlling behaviors and sex-bias-related beliefs were present. The coaches who coached national-level athletes were more likely to be older, more experienced, and were national level athletes themselves. More national-level coaches reported controlling behaviors but fewer held sex bias beliefs than the non-national level coaches. However, the strength of these beliefs (scores for controlling behavior and sex bias) was not related to the coaching success.

Brain Volume Loss, Astrocyte Reduction, and Inflammation in Anorexia Nervosa

Anorexia nervosa is the third most common chronic disease in adolescence and is characterized by low body weight, body image distortion, weight phobia, and severe somatic consequences. Among the latter, marked brain volume reduction has been linked to astrocyte cell count reduction of about 50% in gray and white matter, while neuronal and other glial cell counts remain normal. Exact underlying mechanisms remain elusive; however, first results point to important roles of the catabolic state and the very low gonadal steroid hormones in these patients. They also appear to involve inflammatory states of "hungry astrocytes" and interactions with the gut microbiota. Functional impairments could affect the role of astrocytes in supporting neurons metabolically, neurotransmitter reuptake, and synapse formation, among others. These could be implicated in reduced learning, mood alterations, and sleep disturbances often seen in patients with AN and help explain their rigidity and difficulties in relearning processes in psychotherapy during starvation.

Body fat, cardiovascular risk factors and brain structure in school-age children

BACKGROUND

In adults, cardiovascular risk factors are known to be associated with brain health. We hypothesized that these associations are already present at school-age. We examined the associations of adverse body fat measures and cardiovascular risk factors with brain structure, including volumetric measures and white matter microstructure, in 10-year-old children.

METHODS

We performed a cross-sectional analysis in a population-based prospective cohort study in Rotterdam, the Netherlands. Analyses were based on 3098 children aged 10 years with neuroimaging data and at least one measurement of body fat and cardiovascular risk factors. Body fat measures included body mass index (BMI), fat mass index and android fat mass percentage obtained by Dual-energy X-ray absorptiometry. Cardiovascular risk factors included blood pressure, and serum glucose, insulin and lipids blood concentrations. Structural neuroimaging, including global and regional brain volumes, was quantified by magnetic resonance imaging. DTI was used to assess white matter microstructure, including global fractional anisotropy (FA) and mean diffusivity (MD).

RESULTS

As compared to children with a normal weight, those with underweight had a smaller total brain and white matter volumes (differences -18.10 (95% Confidence Interval (CI) -30.97,-5.22) cm³, -10.64 (95% CI -16.82,-4.47) cm³, respectively). In contrast, one SDS (Standard Deviation Score) increase in fat mass index was associated with a smaller gray matter volume (differences -3.48 (95% CI -16.82, -4.47) cm³). Also, one SDS increase in android fat mass percentage was associated with lower white matter diffusivity (difference -0.06 (95% CI -0.10, -0.02) SDS). None of the other cardiovascular risk factors were associated with any of the brain outcomes.

CONCLUSIONS

Body fat measures, but not other cardiovascular risk factors, were associated with structural neuroimaging outcomes in school-aged children. Prospective studies are needed to assess causality, direction and long-term consequences of the associations.

A longitudinal analysis of cytokines in anorexia nervosa

OBJECTIVE

Inflammation has been proposed to have a pathophysiological role in anorexia nervosa (AN) and to contribute to the maintenance of the disorder. Longitudinal cytokine research in AN has focused on only a few pro-inflammatory cytokines. We assessed a broad range of cytokines over time in people undergoing specialised treatment for AN.

METHOD

We measured serum concentrations of 27 cytokines in people with AN (n = 23). Body mass index (BMI), eating disorder (ED) symptoms and general psychopathology were assessed and blood samples were collected within four weeks of the commencement of specialised ED treatment (baseline) and at 12- and 24-week follow-ups.

RESULTS

Both BMI and ED symptoms improved over the assessment period. Linear mixed models showed that log IL-6 decreased between baseline and week 12 assessments. By week 12, log IL-6 values were comparable to levels in healthy individuals. Log IL-7 increased from week 12 to week 24.

DISCUSSION

Initially elevated IL-6 serum concentrations appear to 'normalize' during the first 3-months of specialised treatment for AN and this co-occurs with improvements in ED symptoms. Therefore, IL-6 has the potential to be a state biomarker for AN.

Increased lipid and lipoprotein concentrations in anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

Alterations in blood lipid concentrations in anorexia nervosa (AN) have been reported; however, the extent, mechanism, and normalization with weight restoration remain unknown. We conducted a systematic review and a meta-analysis to evaluate changes in lipid concentrations in acutely-ill AN patients compared with healthy controls (HC) and to examine the effect of partial weight restoration.

METHOD

A systematic literature review and meta-analysis (PROSPERO: CRD42017078014) were conducted for original peer-reviewed articles.

RESULTS

Forty-eight studies were eligible for review; 33 for meta-analyses calculating mean differences (MD). Total cholesterol (MD = 22.7 mg/dL, 95% CI = 12.5, 33.0), high-density lipoprotein (HDL; MD = 3.4 mg/dL, CI = 0.3, 7.0), low-density lipoprotein (LDL; MD = 12.2 mg/dL, CI = 4.4, 20.1), triglycerides (TG; MD = 8.1 mg/dL, CI = 1.7, 14.5), and apolipoprotein B (Apo B; MD = 11.8 mg/dL, CI = 2.3, 21.2) were significantly higher in acutely-ill AN than HC. Partially weight-restored AN patients had higher total cholesterol (MD = 14.8 mg/dL, CI = 2.1, 27.5) and LDL (MD = 16.1 mg/dL, CI = 2.3, 30.0). Pre- versus post-weight restoration differences in lipid concentrations did not differ significantly.

DISCUSSION

We report aggregate evidence for elevated lipid concentrations in acutely-ill AN patients compared with HC, some of which persist after partial weight restoration. This could signal an underlying adaptation or dysregulation not fully reversed by weight restoration. Although concentrations differed between AN and HC, most lipid concentrations remained within the reference range and meta-analyses were limited by the number of available studies.

Anorexia nervosa and heart disease: a systematic review

Anorexia nervosa (AN) is an eating disorder that most frequently afflicts females in adolescence. In these subjects, cardiovascular complications are the main cause of morbidity and mortality. Aim of this review is to analyze the hemodynamic, pro-arrhythmic and structural changes occurring during all phases of this illness, including re-feeding. A systematic literature search was performed on studies in the MEDLINE database, from its inception until September 2017, with PUBMED interface focusing on AN and cardiovascular disease. This review demonstrated that the most common cardiac abnormalities in AN are bradycardia and QT interval prolongation, which may occasionally degenerate into ventricular arrhythmias such as Torsades des Pointes or ventricular fibrillation. As these arrhythmias may be the substrate of sudden cardiac death (SCD), they require cardiac monitoring in hospital. In addition, reduced cardiac mass, with smaller volumes and decreased cardiac output, may be found. Furthermore, mitral prolapse and a mild pericardial effusion may occur, the latter due to protein deficiency and low levels of thyroid hormone. In anorectic patients, some cases of hypercholesterolemia may be present; however, conclusive evidence that AN is an atherogenic condition is still lacking, although a few cases of myocardial infarction have been reported. Finally, refeeding syndrome (RFS), which occurs during the first days of refeeding, may engender a critically increased risk of acute, life-threatening cardiac complications.

A meta-analysis of cytokine concentrations in eating disorders

Cytokines are signalling molecules, which play an important role in both immune system function and brain development and function, and subsequently mental states and behaviour. Cytokines have been implicated in eating disorders (EDs) due to their role in psychological health, body weight and appetite regulation. This meta-analysis examined cross-sectional and longitudinal studies measuring concentrations of cytokines in individuals with EDs. Using PRISMA guidelines, we systematically reviewed relevant articles in PubMed, Web of Science, and MEDLINE. Random-effects meta-analyses were conducted for interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β, and tumor necrosis factor (TNF)-α, independently, firstly with all EDs combined and then stratified by ED diagnosis. Twenty-five studies were included: serum/plasma cytokine concentrations were measured in people with anorexia nervosa (AN) in 23 studies and bulimia nervosa (BN) in 4 studies. TNF-α and IL-6 were elevated in ED participants compared to healthy controls (HCs). Specifically, this pattern was seen only when comparing AN participants to HCs. Concentrations of these cytokines did not differ between people with BN and HCs. IL-1β and TGF-β did not differ between HCs and any ED group. Therefore, AN seems to be associated with elevated concentrations of TNF-α and IL-6. Considering the role of cytokines in appetite, mood regulation, and anxiety, these pro-inflammatory cytokines could be a potential future drug target to help people with AN, not only with weight gain, but also with various coexisting psychological problems. Future studies should consider confounding factors that affect cytokine concentrations and report ED-relevant clinical characteristics.

Doppler Echocardiography Assessment of Aortic Stiffness in Female Adolescents with Anorexia Nervosa

BACKGROUND

Anorexia nervosa (AN) is associated with abnormalities in biomarkers of cardiovascular risk. Arterial stiffness, as measured by pulse-wave velocity (PWV), is also a risk factor for cardiovascular disease. The aims of this study were to determine the stiffness of the aorta in female adolescents with AN and to determine if either the severity or the type of AN was associated with PWV.

METHODS

This was a retrospective case-control study. Adolescent patients with a clinical diagnosis of AN were included. Aortic diameter and pulse-wave transit time over a portion of the thoracic aorta were measured using Doppler echocardiography, and PWV was calculated.

RESULTS

There were 94 female patients with AN and 60 adolescent female control subjects. There was no significant difference in age between patients with AN and control subjects (15.5 ± 1.7 vs 15.1 ± 2.6 years, P = .220). Body mass index (16.0 ± 2.4 vs 19.7 ± 2.7 kg/m², P < .001) and body mass index percentile (9.4 ± 15.6 vs 45.5 ± 26.2, P < .001) were significantly lower for patients with AN than control subjects. PWV (443 ± 106 vs 383 ± 77 cm/sec, P < .001) was significantly higher in patients with AN than control subjects. Similar differences from control subjects were found in patients with AN with both lower and higher body mass index percentiles and also in patients with AN with the restrictive or the binge-purge subtype.

CONCLUSIONS

Female adolescents with AN have increased aortic stiffness compared with control subjects. This study suggests that patients with AN may be at increased risk for future cardiovascular disease. Future studies are required to determine the reversibility of these changes with weight restoration.

Pro-Inflammatory Cytokines in Psychiatric Disorders in Children and Adolescents: A Review

Cytokines are a large group of small proteins which play a significant role in cell signaling and regulate a variety of processes in organisms, including proliferation and differentiation of many cells, mediation in defense reactions and regulation of hematopoiesis. Cytokines can be divided into those with pro- and those with anti-inflammatory properties. In the group of pro-inflammatory cytokines the most important are: IL-1 beta, IL-6, TNF-alpha, and IFN-gamma. Pro-inflammatory cytokines might be involved in the pathophysiology of many psychiatric conditions in adults, but their role in children and adolescents is less clear. The aim of this article is to demonstrate the patterns of pro-inflammatory cytokines in children and adolescents.

Pro-inflammatory Cytokines in Psychiatric Disorders in Children and Adolescents: A Review

Cytokines are a large group of small proteins which play a significant role in cell signaling and regulate a variety of processes in organisms, including proliferation and differentiation of many cells, mediation in defense reactions and regulation of hematopoiesis. Cytokines can be divided into those with pro- and those with anti-inflammatory properties. In the group of pro-inflammatory cytokines the most important are: IL-1 beta, IL-6, TNF-alpha, and IFN-gamma. Pro-inflammatory cytokines might be involved in the pathophysiology of many psychiatric conditions in adults, but their role in children and adolescents is less clear. The aim of this article is to demonstrate the patterns of pro-inflammatory cytokines in children and adolescents.

Plasma cholesterol is related to menstrual status in adolescent girls with eating disorders and weight loss

AIM

This study examined the relationship between plasma cholesterol and circulating triiodothyronine and oestradiol in 561 adolescent girls aged 11-17 with eating disorders.

METHODS

Plasma total cholesterol, high-density lipoprotein cholesterol, serum triodothyronine and oestradiol were measured at assessment, and historical weight data were obtained from growth charts provided by the school health services. Cholesterol levels were related to weight change, menstrual status and serum hormones.

RESULTS

Plasma total cholesterol levels of >5.0 mmol/L were found in 38% of the 77 girls who were premenarcheal, 32% of the 199 with secondary amenorrhoea and 17% of those who were still menstruating. These cholesterol levels were inversely related to serum oestradiol and triiodothyronine concentrations, but not weight change, in amenorrhoic girls and were positively related to body mass index and inversely related to weight loss and serum triiodothyronine in girls who were still menstruating.

CONCLUSION

Increased plasma total cholesterol was related to amenorrhoea in adolescent girls with eating disorders and weight loss. Oestrogens appeared to mediate the effect of starvation on cholesterol, most effectively in premenarcheal girls. Re-establishing menstruation is an important goal in the treatment of eating disorders, to avoid dyslipidaemia and the risk of future cardiovascular disease.

Oxidative stress and antioxidant levels in patients with anorexia nervosa: A systematic review and exploratory meta-analysis

OBJECTIVE

To systematically review and meta-analyze oxidative stress and antioxidant markers in anorexia nervosa (AN).

METHODS

Electronic PubMed search from database inception until 12/31/2013. Out of 1062 hits, 29 studies comparing oxidative stress/antioxidant markers between patients with AN and healthy controls (HCs) with a total of 1,729 participants (AN = 895, HCs = 834) were eligible. Data about oxidative stress and antioxidant markers, independent of their source, were extracted. We calculated random effects standardized mean differences (SMDs) as effect size measures for outcomes reported in ≥5 studies; others were summarized descriptively.

RESULTS

Compared to HCs, AN patients showed significantly higher apolipoprotein B (ApoB) levels (studies = 7; n = 551; SMD = 0.75; p = .0003, I(2)  = 74%), with higher age being associated with higher ApoB (Coefficient: 0.61 ± 0.15, p < .0001), whereas BMI (p = .15) and measurement method (p = .70) did not moderate the results. Serum albumin levels were similar between AN and HCs (studies = 13; n = 509; SMD =-0.19; 95%CI: -0.62 to 0.24; p = .38; I(2)  = 81%), with neither age (p = .84) nor BMI (p = .52) being significant moderators. Lower superoxide dismutase levels were reported in 2 studies, while findings for vitamin A and its metabolites were inconclusive. In single studies, patients with AN had significantly higher catalase and nitric oxide (NO) parameter levels (platelet NO, exhaled NO and nitrites), such as lower glutathione and free cysteine levels, compared to HCs.

DISCUSSION

AN appears to be associated with some markers of increased oxidative stress. Additional research is needed to discern whether oxidative stress is a potential cause or effect of AN, and whether treatments improving oxidative stress could be useful in AN.

Association of distorted eating behaviors with cardiometabolic risk indices in preadolescents. The Healthy Growth Study

The association between distorted eating behavior (DEB) with cardiometabolic risk (CMR) in children has been poorly investigated. The aim of the study was to examine the association between DEB with certain CMR indices in 9- to 13-year-old children in Greece. A cross-sectional epidemiological study was conducted among 1803 schoolchildren from 77 primary schools in 4 counties of Greece with full data on DEBQ and ChEAT questionnaires and CMR indices. Children underwent anthropometric measurements and Tanner stage, serum lipid, glucose, insulin and HOMA-IR levels assessments. Univariate and multivariate linear regression analyses were performed to test for the association between components of DEBQ and ChEAT with CMR indices. Several significant associations between components of DEBQ and ChEAT with CMR indices were observed when tested at univariate regression models in both boys and girls. However, after adjusting for several possible confounders, including Tanner stage, all significant associations were lost in girls while only a few remained in boys. Thus, DEB might have an unfavorable effect also in certain CMR indices, besides nourishment status. This is more pronounced in preadolescent boys for whom hormonal changes due to the transition to adolescence have not yet been established compared to girls. Still further research is needed to shed more light on these associations.

Inflammatory cytokines and anorexia nervosa: A meta-analysis of cross-sectional and longitudinal studies

OBJECTIVE

Although inflammation is increasingly implicated in psychiatric disorders, less is known about its role in anorexia nervosa (AN), an illness with low body mass index (BMI).

METHODS

We performed a systematic PubMed literature search until 12/31/2013 and meta-analyzed cross-sectional and longitudinal studies comparing circulating pro- and anti-inflammatory cytokines between patients with anorexia nervosa (AN) and healthy controls (HCs) (1) before and (2) after weight gain, and (3) within AN patients before and after weight gain. Standardized mean differences (SMDs)± 95% confidence intervals (CIs) for results from ≥ 2 studies were calculated.

RESULTS

Of 999 initial hits, 22 studies with 924 participants (AN=512, HCs=412) were eligible. Compared to HCs, tumor necrosis factor (TNF)-alpha (SMD=0.35, 95%CI=0.09-0.61, p=0.008), interleukin (IL)1-beta (SMD=0.51, 95%CI=0.18-0.84, p=0.003), IL-6 (SMD=0.43, 95%CI=0.11-0.76, p=0.009), and TNF-receptor-II (SMD=0.42, 95%CI:0.07-0.78, p=0.02) were significantly elevated in AN, while C-reactive protein (SMD=-0.53, 95%CI=-.77, -0.28, p<0.0001) and IL-6 receptor (SMD=-0.85, 95%CI=-1.33, -0.36, p=0.0006) were significantly decreased. No differences were found for TNF-receptor I and TGF-β. Across a subset of eight longitudinal studies (AN=152, HCs=129), significant weight gain (baseline BMI=15.4 ± 1.5, endpoint BMI=18.2 ± 1.6, p<0.0001) was not associated with significant changes in TNF-α, IL-6 and IL1-β. However, after weight gain, IL-6 was not different anymore compared to HCs (SMD=0.06, 95%CI=-0.32, 0.45, p=0.75). In meta-regression, shorter illness duration (p=0.0008), but not younger age (p=0.71) significantly moderated greater IL-6 levels.

CONCLUSION

Despite abnormally low BMI, AN seems to be associated with increased inflammatory cytokines. Whether specific elevated cytokines represent trait or state markers of AN, and whether they could be treatment targets requires further study.

Endocrinology of anorexia nervosa in young people: recent insights

PURPOSE OF REVIEW

Anorexia nervosa is among the most prevalent chronic medical conditions in young adults. It has acute as well as long-term consequences, some of which, such as low bone mineral density (BMD), are not completely reversible even after weight restoration. This review discusses our current understanding of endocrine consequences of anorexia nervosa.

RECENT FINDINGS

Anorexia nervosa is characterized by changes in multiple neuroendocrine axes including acquired hypogonadotropic hypogonadism, growth hormone resistance with low insulin-like growth factor-1 (likely mediated by fibroblast growth factor-1), relative hypercortisolemia, alterations in adipokines such as leptin, adiponectin and resistin, and gut peptides including ghrelin, PYY and amylin. These changes in turn contribute to low BMD. Studies in anorexia nervosa have demonstrated abnormalities in bone microarchitecture and strength, and an association between increased marrow fat and decreased BMD. One study in adolescents reported an improvement in BMD following physiologic estrogen replacement, and another in adults demonstrated improved BMD following risedronate administration. Brown adipose tissue is reduced in anorexia nervosa, consistent with an adaptive response to the energy deficit state.

SUMMARY

Anorexia nervosa is associated with widespread physiologic adaptations to the underlying state of undernutrition. Hormonal changes in anorexia nervosa affect BMD adversely. Further investigation is underway to optimize therapeutic strategies for low BMD.

Adipocytokine levels in women with anorexia nervosa. Relationship with weight restoration and disease duration

OBJECTIVE

Starvation-induced depletion of fat stores in anorexia nervosa (AN) is known to be accompanied by alterations in some circulating adipocytokines. We analyzed a panel of circulating adipocytokines in women with AN compared with normal-weight controls and their relation with the disease duration and weight restoration.

METHOD

We analyzed circulating adipocytokine levels in 28 patients with AN and in 33 normal-weight controls who were eating healthily. We determined by enzyme-linked immunosorbent assay the circulating levels of total and high molecular weight (HMW) adiponectin, lipocalin-2 (LCN2), leptin, tumor necrosis factor receptor-II (TNFRII), interleukin-6 (IL6), adipocyte fatty acid binding protein-4 (FABP4), ghrelin, and resistin.

RESULTS

The two circulating forms of adiponectin are higher in AN women compared with controls. Both total and HMW adiponectin related negatively to the duration of the disease (r = -0.372, p = 0.033; r = -0.450, p = 0.038, respectively). Furthermore, the lipid binding-proteins LCN2 and FABP4 are lower in AN compared to the control group. Finally, leptin levels are lower in AN against controls and correlated positively with disease duration (r = 0.537, p = 0.007). Resistin, ghrelin, TNFRII, and IL6 have similar values in both groups, although TNFRII and ghrelin related negatively to body mass index variation at the end of treatment (r = -0.456, p = 0.039; r = -0.536, p = 0.015, respectively).

DISCUSSION

These results suggest there is a need to investigate if changes in adipocytokine levels could serve as weight restoration biomarkers. Further studies are warranted to elucidate the specific role of these molecules in the timing of weight restoration.

Inhibition of Pref-1 (preadipocyte factor 1) by oestradiol in adolescent girls with anorexia nervosa is associated with improvement in lumbar bone mineral density

OBJECTIVE

Adolescents with anorexia nervosa (AN) are amenorrheic and have decreased bone mass accrual and low bone mineral density (BMD). The regulation of mesenchymal stem cell differentiation is an important factor governing bone formation. Preadipocyte factor 1 (Pref-1), an inhibitor of adipocyte and osteoblast differentiation, is elevated in states of oestrogen deficiency. In this study, we aim to (i) investigate effects of transdermal oestradiol on Pref-1 in adolescent girls with AN, and (ii) examine associations of changes in Pref-1 with changes in lumbar BMD and bone turnover markers.

DESIGN

Adolescent girls with AN and normal-weight controls were studied cross-sectionally. Girls with AN were examined longitudinally in a double-blind study and received transdermal oestradiol (plus cyclic medroxyprogesterone) or placebo for 12 months.

PATIENTS

Sixty-nine girls (44 with AN, 25 normal-weight controls) 13-18 years were studied at baseline; 22 AN girls were followed prospectively.

MEASUREMENTS

Pref-1 levels, bone formation and resorption markers, and BMD.

RESULTS

Pref-1 levels decreased in girls with AN after treatment with transdermal oestradiol compared with placebo (-0·015 ± 0·016 vs 0·060±0·026 ng/ml, P = 0·01), although at baseline, levels did not differ in AN vs controls (0·246 ± 0·015 vs 0·267 ± 0·022 ng/ml). Changes in Pref-1 over 12 months correlated inversely with changes in lumbar BMD (r = -0·48, P = 0·02) and positively with changes in CTX (r = 0·73, P = 0·006).

CONCLUSIONS

For the first time, we show that Pref-1 is negatively regulated by oestradiol in adolescent girls with AN. Inhibition of Pref-1 may mediate the beneficial effects of transdermal oestradiol replacement on BMD in girls with AN.

Long-term consequences of anorexia nervosa

Anorexia nervosa (AN) is a psychiatric disorder that occurs mainly in female adolescents and young women. The obsessive fear of weight gain, critically limited food intake and neuroendocrine aberrations characteristic of AN have both short- and long-term consequences for the reproductive, cardiovascular, gastrointestinal and skeletal systems. Neuroendocrine changes include impairment of gonadotropin releasing-hormone (GnRH) pulsatile secretion and changes in neuropeptide activity at the hypothalamic level, which cause profound hypoestrogenism. AN is related to a decrease in bone mass density, which can lead to osteopenia and osteoporosis and a significant increase in fracture risk in later life. Rates of birth complications and low birth weight may be higher in women with previous AN. The condition is associated with fertility problems, unplanned pregnancies and generally negative attitudes to pregnancy. During pregnancy, women with the condition have higher rates of hyperemesis gravidarum, anaemia and obstetric complications, as well as impaired weight gain and compromised intrauterine foetal growth. It is reported that 80% of AN patients are affected by a cardiac complications such as sinus bradycardia, a prolonged QT interval on electrocardiography, arrythmias, myocardial mass modification and hypotension. A decrease in bone mineral density (BMD) is one of the most important medical consequences of AN. Reduced BMD may subsequently lead to a three- to seven-fold increased risk of spontaneous fractures. Untreated AN is associated with a significant increase in the risk of death. Better detection and sophisticated therapy should prevent the long-term consequences of this disorder. The aims of treatment are not only recovery but also prophylaxis and relief of the long-term effects of this disorder. Further investigations of the long-term disease risk are needed.

Triiodothyronine (T3) and metabolic rate in adolescents with eating disorders: Is there a correlation?

AIM

To examine the correlation between T3 and resting energy expenditure (REE) in adolescent patients with eating disorders (ED) to assess whether T3 can be used to predict metabolic rate suppression and recovery.

METHODS

A retrospective chart review was performed on patients with ED (Anorexia Nervosa [AN], Bulimia Nervosa [BN], and Eating Disorder NOS [EDNOS]), aged 11-22 years, who had T3 and REE measured within 1 month (N=38 AN, 32 BN/EDNOS). REE was measured by indirect calorimetry (IC) and represented as the percentage of expected REE (%EREE) predicted by the Harris-Benedict equation. Pearson correlation coefficients were calculated to examine the relationship between T3 and %EREE and how each correlates with anthropometric data, laboratory values, and diagnosis.

RESULTS

T3 was significantly correlated with %EREE in the AN group but not in the total population or BN/EDNOS group. In the total study population, T3 alone correlated significantly with weight, Body Mass Index (BMI), BMI percentile, %Ideal Body Weight (%IBW), %Maximum Weight Lost (%MWL), LH, and estradiol. In the AN group, T3 and %EREE both correlated with BMI, BMI percentile, LH, and estradiol; however, only T3 correlated with %IBW and %MWL. In the BN/EDNOS group, T3 correlated with BMI, BMI percentile, %IBW, and estradiol while %EREE correlated with none.

CONCLUSION

In patients with AN, T3 correlated significantly with markers of malnutrition and %EREE and may serve as a surrogate measure when IC is unavailable. Following T3 during treatment of AN may assist clinicians in assessing metabolic suppression and recovery and help guide caloric prescriptions and goal weights.

The clinical biochemistry of anorexia nervosa

In anorexia nervosa, under-nutrition and weight regulatory behaviours such as vomiting and laxative abuse can lead to a range of biochemical problems. Hypokalaemia is the most common electrolyte abnormality. Metabolic alkalosis occurs in patients who vomit or abuse diuretics and acidosis in those misusing laxatives. Hyponatraemia is often due to excessive water ingestion, but may also occur in chronic energy deprivation or diuretic misuse. Urea and creatinine are generally low and normal concentrations may mask dehydration or renal dysfunction. Abnormalities of liver enzymes are predominantly characterized by elevation of aminotransferases, which may occur before or during refeeding. The serum albumin is usually normal, even in severely malnourished patients. Amenorrhoea is due to hypogonadotrophic hypogonadism. Reduced concentrations of free T4 and free T3 are frequently reported and T4 is preferentially converted to reverse T3. Cortisol is elevated but the response to adrenocorticotrophic hormone is normal. Hypoglycaemia is common. Hypercholesterolaemia is a common finding but its significance for cardiovascular risk is uncertain. A number of micronutrient deficiencies can occur. Other abnormalities include hyperamylasaemia, hypercarotenaemia and elevated creatine kinase. There is an increased prevalence of eating disorders in type 1 diabetes and the intentional omission of insulin is associated with impaired metabolic control. Refeeding may produce electrolyte abnormalities, hyper- and hypoglycaemia, acute thiamin depletion and fluid balance disturbance; careful biochemical monitoring and thiamin replacement are therefore essential during refeeding. Future research should address the management of electrolyte problems, the role of leptin and micronutrients, and the possible use of biochemical markers in risk stratification.

Iron metabolism in patients with anorexia nervosa: elevated serum hepcidin concentrations in the absence of inflammation

BACKGROUND

Only a few studies based on small cohorts have been carried out on iron status in anorexia nervosa (AN) patients.

OBJECTIVE

The aim of this study was to evaluate the role of hepcidin in hyperferritinemia in AN adolescents.

DESIGN

Twenty-seven adolescents hospitalized for AN in the pediatric inpatient unit of Ambroise Paré Academic Hospital were enrolled in the study. The control group comprised 11 patients. Hematologic variables and markers of iron status, including serum hepcidin, were measured before and after nutritional rehabilitation.

RESULTS

The mean age of patients was 14.4 y. Except for 2 AN patients and 1 control patient, all patients presented normal hemoglobin, vitamin B-12, and folate concentrations. Markers of inflammation and cytokines were normal throughout the study. None of the muscular lysis markers were elevated. Most AN patients had normal serum iron concentrations on admission. Serum ferritin concentrations were significantly higher in patients than in control subjects (198 compared with 49 μg/L, respectively; P < 0.001). The median hepcidin concentration was significantly higher in AN patients than in the control group (186.5 compared with 39.5 μg/L, respectively; P = 0.002). There was a highly significant correlation between ferritinemia and serum hepcidin concentrations (P < 0.0001). After nutritional rehabilitation, a significant reduction was observed (P = 0.004) in serum ferritin. Serum hepcidin analyzed in a smaller number of patients also returned to within the normal range.

CONCLUSIONS

Hepcidin and ferritin concentrations were higher in the serum of AN patients, without any evidence of iron overload or inflammation. These concentrations returned to normal after nutritional rehabilitation. These results suggest that nutritional stress induced by malnourishment in the hepatocyte could be yet another mechanism that regulates hepcidin.

Immunological disturbance and infectious disease in anorexia nervosa: a review

OBJECTIVE

Severely malnourished patients with anorexia nervosa (AN) are reported to show fewer symptomatic viral infections and a poorer response to bacterial infection than controls. They are also reported to show mild immune system changes, although the relevance of these to altered infection disease presentation in AN and AN pathophysiology is unknown. Thus, in this paper, we suggest a range of immune system changes that might underpin these altered responses to common pathogens, and review a number of recent infectious disease findings for their utility in explaining the pathophysiology of AN.

METHODS

A systematic review of the literature pertaining to immunity and infectious disease in AN was performed.

RESULTS

AN is associated with leucopenia, and the increased spontaneous and stimulated levels of proinflammatory cytokines [i.e. interleukin (IL)-1β, IL-6 and tumour necrosis factor α). A range of less consistent findings are also reviewed. Most of these data were not controlled for length of illness, degree of malnutrition, micronutrient or vitamin deficiencies or recent refeeding and starvation.

CONCLUSION

Cytokine disturbances have been suggested to be causally related to AN symptomatology and pathophysiology of AN, although the evidence supporting this assertion is lacking. Immune and cytokine changes in AN do, however, occur in association with a decreased incidence of symptomatic viral infection, decreased clinical response to bacterial infection leading to delayed diagnosis and increased morbidity and mortality associated with the infections.

Towards a physiologically based diagnosis of anorexia nervosa and bulimia nervosa

Diagnosis of anorexia nervosa (AN) and bulimia nervosa (BN), while including such physiological data as weight and the reproductive status of the individual, are primarily based on questionnaires and interviews that rely on self-report of both body-related concerns and eating-related behaviors. While some key components of eating disorders are psychological and thus introspective in nature, reliance on self-report for the assessment of eating-related behaviors and nutritional status lacks the objectivity that a physiologically based measure could provide. The development of a more physiologically informed diagnosis for AN and BN would provide a more objective means of diagnosing these disorders, provide a sound physiological basis for diagnosing subclinical disorders and could also aid in monitoring the effectiveness of treatments for these disorders. Empirically supported, physiologically based methods for diagnosing AN and BN are reviewed herein as well as promising physiological measures that may potentially be used in the diagnosis of AN and BN.