Hypoglycaemia following a mixed meal in eating disorder patients

Associations between low body weight, weight loss, and medical instability in adults with eating disorders

OBJECTIVE

The physical complications of atypical anorexia nervosa remain understudied, with most studies completed in adolescents. This study seeks to examine the impact of various weight measures as predictors of medical instability in a large cohort of adult eating disorder patients.

METHODS

In this retrospective cohort study, the impact of admission body mass index (BMI), weight suppression, and recent weight loss (the rate of weight loss within the last 12 months) toward the development of medical complications of malnutrition were examined. Multivariable logistic regression assessed the association of binary clinical outcomes of interest with recent weight loss and weight suppression (adjusting for age, admission BMI, gender, and purging behaviors). Odds ratios (OR) and 99% confidence intervals were reported.

RESULTS

Greater recent weight loss increased the odds of developing low prealbumin and reduced hand grip strength. A greater weight suppression was associated with increased likelihood of amenorrhea, reduced systolic blood pressure, nadir hemoglobin, and weekly weight gain upon nutritional rehabilitation. Lower admission BMI was predictive of all the medical outcomes examined, with the exception of bradycardia, and was generally the strongest predictor based on standardized coefficients.

DISCUSSION

Recent weight loss and weight suppression are predictive of some of the physiologic changes of malnutrition, although low BMI is seemingly the greatest predictor for the development of these complications. These findings suggest that some patients with aggressive weight suppression and/or acute weight loss would benefit from medical stabilization, although this needs to be further defined.

PUBLIC SIGNIFICANCE

In adults, low BMI seems to be a better predictor of medical complications than weight suppression or aggressive recent weight loss. In adults, greater weight suppression is associated with increased likelihood of amenorrhea, reduced systolic blood pressure, nadir hemoglobin, and weight gain upon nutritional rehabilitation.

Anorexia nervosa: Outpatient treatment and medical management

Anorexia nervosa (AN) is a disabling, costly and potentially deadly illness. Treatment failure and relapse are common after completing treatment, and a substantial proportion of patients develop severe and enduring AN. The time from AN debut to the treatment initiation is normally unreasonably long. Over the past 20 years there has been empirical support for the efficacy of several treatments for AN. Moreover, outpatient treatment with family-based therapy or individual psychotherapy is associated with good outcomes for a substantial proportion of patients. Early intervention improves outcomes and should be a priority for all patients. Outpatient treatment is usually the best format for early intervention, and it has been demonstrated that even patients with severe or extreme AN can be treated as outpatients if they are medically stable. Inpatient care is more disruptive, more costly, and usually has a longer waiting list than does outpatient care. The decision as to whether to proceed with outpatient treatment or to transfer the patient for inpatient therapy may be difficult. The core aim of this opinion review is to provide the knowledge base needed for performing safe outpatient treatment of AN. The scientific essentials for outpatient treatment are described, including how to assess and manage the medical risks of AN and how to decide when transition to inpatient care is indicated. The following aspects are discussed: early intervention, outpatient treatment of AN, including outpatient psychotherapy for severe and extreme AN, how to determine when outpatient treatment is safe, and when transfer to inpatient healthcare is indicated. Emerging treatments, ethical issues and outstanding research questions are also addressed.

Autonomic nervous system function in women with anorexia nervosa

PURPOSE

Abnormalities in autonomic function have been observed in people with anorexia nervosa. However, the majority of investigations have utilised heart rate variability as the sole assessment of autonomic activity. The current study utilised a variety of methodologies to assess autonomic nervous system function in women with a current diagnosis of anorexia, a past diagnosis of anorexia who were weight-restored, and healthy controls.

METHODS

The sample included 37 participants: 10 participants with anorexia, 17 weight-restored participants (minimum body mass index > 18.5 for minimum of 12 months) and 10 controls. Assessments of autonomic function included muscle sympathetic nerve activity (MSNA) using microneurography, heart rate variability, baroreflex sensitivity, blood pressure variability, head-up tilt table test, sudomotor function and assessment of plasma catecholamines.

RESULTS

MSNA (bursts/min) was significantly decreased in both anorexia (10.22 ± 6.24) and weight-restored (17.58 ± 1.68) groups, as compared to controls (23.62 ± 1.01, p < 0.001 and p = 0.033, respectively). Participants with anorexia had a significantly lower standard deviation in heart rate, lower blood pressure variability and decreased sudomotor function as compared to controls. Weight-restored participants demonstrated decreased baroreflex sensitivity in response to head-up tilt as compared to controls.

CONCLUSION

Women with a current or previous diagnosis of anorexia have significantly decreased sympathetic activity, which may reflect a physiological response to decreased energy intake. During the state of starvation, women with anorexia also displayed decreased sudomotor function. The consequences of a sustained decrease in MSNA are unknown, and future studies should investigate autonomic function in long-term weight-restored participants to determine whether activity returns to normal.

The application of continuous glucose monitoring technology to eating disorders research: An idea worth researching

Continuous glucose monitoring (CGM) devices have revolutionized our capacity to measure blood glucose levels in real time using minimally invasive technology, yet to date there are no studies using CGM in individuals with eating disorders (EDs). Preliminary evidence suggests that eating disorder behaviors (EDBs) have substantial and characteristic impacts on blood glucose levels and glucose-related variables (e.g., binge-eating episodes cause rapid spikes in blood glucose levels, purging causes rapid drops in blood glucose to below normal levels). The aims of this article are to describe the benefits of CGM technology over older methods of measuring blood glucose levels and to discuss several specific ways in which CGM technology can be applied to EDs research to (a) improve our ability to identify and predict engagement in EDBs in real time, (b) identify relationships between blood glucose levels and maintenance factors for EDs, and (c) increase our understanding of the physiological and psychological impacts of disordered eating. We also present preliminary acceptability and feasibility data on the use of CGM devices in individuals with EDs. Overall, the article will describe several applications of CGM technology in EDs research with compelling potential to improve research methodologies.

Refeeding Syndrome with Hypoglycemia in a Severely Malnourished Infant

A 5-mo-old severely malnourished 3.5 kg boy was brought to the emergency department with hypoglycemia, bradycardia, bradypnea, and hypothermia. His findings were likely due to severe malnutrition secondary to parental neglect. Resuscitation with dextrose containing intravenous fluids was promptly started. On day 2 of admission, refeeding was initiated. From that time, he had multiple hypoglycemic episodes along with hypophosphatemia, hypomagnesemia, and hypokalemia. Hypoglycemia was associated with the initiation of enteral feeding and an increase in calories and amounts of enteral feeding. Hypoglycemia associated with refeeding syndrome in infant has not been previously reported.

An update on the medical consequences of anorexia nervosa

PURPOSE OF REVIEW

The diagnosis of anorexia nervosa is associated with the highest mortality rate of any psychiatric disorder, mainly caused by medical complications.The purpose of this article is to review the common medical consequences of anorexia nervosa focusing on the special considerations related to children and adolescents and recent updates on the pathophysiology of these complications and their prognosis significance.

RECENT FINDINGS

The main findings were related to the diagnostic and prognostic value of hypokalaemia, QTc prolongation, hypoglycaemia and orthostatic changes. A new modality to evaluate the heart in anorexia nervosa was explored (2DSTE) as well. Bone mineral density (BMD) loss is one of the few nonreversible consequences of anorexia nervosa. BMD loss does not seem to be significantly related to sex or to cut-off low-weight parameters in teenagers with anorexia nervosa, but rather to the amount of weight loss they have experienced. Brain volume deficits might be another irreversible complication in adolescents with anorexia nervosa.

SUMMARY

It is crucial for any healthcare provider to be informed about the medical consequences of anorexia nervosa, not only because they can be devastating, but also because they can play an essential role in motivating patients to get treated.

Effects of starvation and short-term refeeding on gastric emptying and postprandial blood glucose regulation in adolescent girls with anorexia nervosa

Postprandial glucose is reduced in malnourished patients with anorexia nervosa (AN), but the mechanisms and duration for this remain unclear. We examined blood glucose, gastric emptying, and glucoregulatory hormone changes in malnourished patients with AN and during 2 wk of acute refeeding compared with healthy controls (HCs). Twenty-two female adolescents with AN and 17 age-matched female HCs were assessed after a 4-h fast. Patients were commenced on a refeeding protocol of 2,400 kcal/day. Gastric emptying (¹³C-octanoate breath test), glucose absorption (3-O-methylglucose), blood glucose, plasma glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), insulin, C-peptide, and glucagon responses to a mixed-nutrient test meal were measured on admission and 1 and 2 wk after refeeding. HCs were assessed once. On admission, patients had slower gastric emptying, lower postprandial glucose and insulin, and higher glucagon and GLP-1 than HCs ( P < 0.05). In patients with AN, the rise in glucose (0-30 min) correlated with gastric emptying ( P < 0.05). With refeeding, postprandial glucose and 3-O-methylglucose were higher, gastric emptying faster, and baseline insulin and C-peptide less ( P < 0.05), compared with admission. After 2 wk of refeeding, postprandial glucose remained lower, and glucagon and GLP-1 higher, in patients with AN than HCs ( P < 0.05) without differences in gastric emptying, baseline glucagon, or postprandial insulin. Delayed gastric emptying may underlie reduced postprandial glucose in starved patients with AN; however, postprandial glucose and glucoregulatory hormone changes persist after 2 wk of refeeding despite improved gastric emptying. Future research should explore whether reduced postprandial glucose in AN is related to medical risk by examining associated symptoms alongside continuous glucose monitoring during refeeding.

Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for the treatment of eating disorders

OBJECTIVES

This clinical practice guideline for treatment of DSM-5 feeding and eating disorders was conducted as part of the Royal Australian and New Zealand College of Psychiatrists (RANZCP) Clinical Practice Guidelines (CPG) Project 2013-2014.

METHODS

The CPG was developed in accordance with best practice according to the National Health and Medical Research Council of Australia. Literature of evidence for treatments of anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), other specified and unspecified eating disorders and avoidant restrictive food intake disorder (ARFID) was sourced from the previous RANZCP CPG reviews (dated to 2009) and updated with a systematic review (dated 2008-2013). A multidisciplinary working group wrote the draft CPG, which then underwent expert, community and stakeholder consultation, during which process additional evidence was identified.

RESULTS

In AN the CPG recommends treatment as an outpatient or day patient in most instances (i.e. in the least restrictive environment), with hospital admission for those at risk of medical and/or psychological compromise. A multi-axial and collaborative approach is recommended, including consideration of nutritional, medical and psychological aspects, the use of family based therapies in younger people and specialist therapist-led manualised based psychological therapies in all age groups and that include longer-term follow-up. A harm minimisation approach is recommended in chronic AN. In BN and BED the CPG recommends an individual psychological therapy for which the best evidence is for therapist-led cognitive behavioural therapy (CBT). There is also a role for CBT adapted for internet delivery, or CBT in a non-specialist guided self-help form. Medications that may be helpful either as an adjunctive or alternative treatment option include an antidepressant, topiramate, or orlistat (the last for people with comorbid obesity). No specific treatment is recommended for ARFID as there are no trials to guide practice.

CONCLUSIONS

Specific evidence based psychological and pharmacological treatments are recommended for most eating disorders but more trials are needed for specific therapies in AN, and research is urgently needed for all aspects of ARFID assessment and management.

EXPERT REVIEWERS

Associate Professor Susan Byrne, Dr Angelica Claudino, Dr Anthea Fursland, Associate Professor Jennifer Gaudiani, Dr Susan Hart, Ms Gabriella Heruc, Associate Professor Michael Kohn, Dr Rick Kausman, Dr Sarah Maguire, Ms Peta Marks, Professor Janet Treasure and Mr Andrew Wallis.