A standard enteral formula versus an iso-caloric lower carbohydrate/high fat enteral formula in the hospital management of adolescent and young adults admitted with anorexia nervosa: a randomised controlled trial

Severe hypoglycemia with reduced liver volume as an indicator of end-stage malnutrition in patients with anorexia nervosa: a retrospective observational study

BACKGROUND

Hypophosphatemia due to excessive carbohydrate administration is considered the primary pathogenesis of refeeding syndrome. However, its association with liver injury and hypoglycemia, often seen in severe malnutrition before re-nutrition, remains unclear. Autophagy reportedly occurs in the liver of patients with severe malnutrition. This study aimed to clarify the pathophysiology of liver injury and hypoglycemia by focusing on liver volume.

METHODS

Forty-eight patients with anorexia nervosa with a body mass index (BMI) of < 13 kg/m2 were included (median BMI: 10.51 kg/m2 on admission). Liver volume was measured in 36 patients who underwent abdominal computed tomography (CT), and the "estimated liver weight/ideal body weight" was used as the liver volume index. Seventeen blood test items were analyzed during the first 60 days.

RESULTS

Liver volume significantly decreased when abdominal CTs were conducted shortly before or after hypoglycemia compared to when the scans were performed during periods without hypoglycemia. Five patients with severe hypoglycemia on days 13-18 after admission had a very low nutritional intake; of them, four showed a marked decrease in liver volume. Severe hypoglycemia was accompanied by low serum triglycerides and liver dysfunction. Patients experiencing hypoglycemia of blood glucose levels < 55 mg/dL (< 3.05 mmol/L) (32 patients; median lowest BMI: 9.45 kg/m2) exhibited significantly poorer blood findings for most of the 17 items, except serum phosphorus and potassium, than did those not experiencing hypoglycemia (16 patients; median lowest BMI: 11.2 kg/m2). All patients with a poor prognosis belonged to the hypoglycemia group. Empirically, initiating re-nutrition at 500 kcal/day (20-25 kcal/kg/day), increasing to 700-800 kcal/day after a week, and then gradually escalating can reduce serious complications following severe hypoglycemia.

CONCLUSIONS

Liver volume reduction accompanied by hypoglycemia, low serum triglyceride levels, and liver dysfunction occurs when the body's stored energy sources are depleted and external nutritional intake is inadequate, suggesting that the liver was consumed as a last resort to obtain energy essential for daily survival. This pathophysiology, distinct from refeeding syndrome, indicates the terminal stage of malnutrition and is a risk factor for complications and poor prognosis. In treatment, extremely low nutrient levels should be avoided.

Clinical Outcomes of Refeeding Syndrome: A Systematic Review of High vs. Low-Calorie Diets for the Treatment of Anorexia Nervosa and Related Eating Disorders in Children and Adolescents

Over the years, the standard of care for re-alimentation of patients admitted for the treatment of anorexia nervosa (AN) has been a conservative or cautious approach described as "start low and go slow." These traditional refeeding protocols advocate for a low-calorie diet that restricts carbohydrates, with the primary goal of hypothetically lowering the risk of refeeding syndrome (RFS) and its complication. However, no consensus exists for the optimal inpatient approach to refeeding children and adolescents with AN. There is still some disagreement about what constitutes an ideal pace for nutritional rehabilitation. Varying treatment protocols have emerged across the globe, often reflecting the preferences and biases of individual practitioners and contributing to the lack of a universally accepted protocol for refeeding in AN. Although it is widely accepted that low-caloric refeeding (LCR) is safe for inpatient treatment of AN, this strategy has been shown to have several significant drawbacks, leading to increased criticism of the LCR method. Research from the last decade has led to calls for a more aggressive refeeding protocol, one that suggests a higher caloric intake from the offset. As a result, this research aimed to conduct a systematic review of the existing literature on strategies for refeeding hospitalized pediatric/adolescent patients with AN and related eating disorders. We aimed to compare high-caloric refeeding (HCR) and LCR in terms of weight gain, length of stay, and risk of RFS. We conducted a thorough search of medical databases for abstracts published in English, including Google Scholar, PubMed, and MEDLINE, to find relevant studies published between 2010 and February 2023. Our focus was on articles that evaluated high versus low refeeding protocols in children and adolescents hospitalized for treating AN and related eating disorders. Only articles that reported on at least one of the outcome variables of interest, such as hypophosphatemia, weight gain, RFS, or length of hospital stay, were considered. This review included 20 full-text articles published in the last decade on the HCR protocol in children and adolescents, with a total sample size of 2191 participants. In only one of the 20 studies did researchers find evidence of a true clinical case of RFS. We, therefore, found no evidence that HCR increased the risk of RFS in adolescents, even in those with a very low body mass index (BMI). However, evidence suggests a lower BMI at the time of hospital admission is a better predictor of hypophosphatemia than total caloric intake. In conclusion, based on the evidence from this review, a high-caloric diet or rapid refeeding in children/adolescents suffering from AN may be both safe and effective, with serial laboratory investigations and phosphate supplementation as needed. Hence, more research, particularly, randomized controlled trials, is required to help shape an evidence-based refeeding guideline outlining target calorie intakes and rates of advancement to assist clinicians in the treatment of adolescents with AN and related eating disorders.

Unique considerations for the medical care of restrictive eating disorders in children and young adolescents

BACKGROUND

The medical complications of eating disorders are often approached through an age-neutral lens. However, children and young adolescents may have unique medical complications related to the energy needs and timing of growth and development. Providers caring for patients in this vulnerable age range should understand how to identify, approach, and manage these potential age-related complications.

REVIEW

Evidence continues to accumulate that increasingly younger patients are being diagnosed with eating disorders. These children and young adolescents have significant risk for unique and potentially irreversible medical complications. Without early identification and treatment, restrictive eating disorders may negatively impact linear growth, bone development and brain maturation in children and young adolescents. Additionally, due to the energy needs of growth and development, unique considerations exist for the use of acute medical stabilization and the identification of patients at risk for refeeding syndrome with initial nutritional rehabilitation. This review presents an approach to the evaluation and management of children and young adolescents with eating disorders.

CONCLUSION

Children and young adolescents with restrictive eating disorders may have unique medical complications related to the energy needs and timing of linear growth and pubertal development. Significant risk exists for irreversible medical complications of impaired growth, bone, and brain health. Increased awareness of the energy needs for growth and development may improve early recognition, appropriate intervention, and future outcomes for children and young adolescents with restrictive eating disorders.

Anorexia nervosa and muscle health: A systematic review of our current understanding and future recommendations for study

OBJECTIVE

Conduct a systematic review on muscle size and strength in individuals with anorexia nervosa (AN).

METHOD

In accordance with PRISMA guidelines, we searched Pubmed for articles published between 1995 and 2022 using a combination of search terms related to AN and muscle size, strength, or metabolism. After two authors screened articles and extracted data, 30 articles met inclusion criteria. Data were coded, and a risk bias was conducted for each study.

RESULTS

The majority of studies focused on muscle size/lean mass (60%, n = 18) and energy expenditure (33%, n = 9), with few studies (17%, n = 5) investigating muscle function or possible mechanisms underlying muscle size (20%, n = 6). Studies supported that individuals with AN have smaller muscle size and reduced energy expenditure relative to controls. In some studies (33%, n = 10) recovery from AN was not sufficient to restore muscle mass or function. Mechanisms underlying short and long-term musculoskeletal alterations have not been thoroughly explored.

DISCUSSION

Muscle mass and strength loss may be an unexplored component of physiological deterioration during and after AN. More research is necessary to understand intramuscular alterations during AN and interventions to facilitate muscle mass and functional gain following weight restoration in AN.

PUBLIC SIGNIFICANCE

Muscle health is important for optimal health and is reduced in individuals with AN. However, we do not understand how muscle is altered at the cellular level throughout the course of AN. Here we review what is currently known regarding muscle health during AN and with weight restoration.

To Improve the Initial Inpatient Management of Adolescents Admitted with Severe Anorexia Nervosa: A Narrative Review and a Convenient Protocol

Inadequate nutritional rehabilitation of severely malnourished adolescents with Anorexia Nervosa (AN) increases the risk of medical complications. There is no consensus on best practices for inpatient nutritional rehabilitation and medical stabilization for severe AN. This study aimed to elaborate an admission protocol for adolescents with severe AN based on a comprehensive narrative review of current evidence. A Pubmed search was conducted in July 2017 and updated in August 2020, using the keywords severe AN or eating disorders (ED), management guidelines and adolescent. Relevant references cited in these guidelines were retrieved. A secondary search was conducted using AN or ED and refeeding protocol, refeeding syndrome (RS), hypophosphatemia, hypoglycemia, cardiac monitoring or cardiac complications. Evidence obtained was used to develop the admission protocol. Selective blood tests were proposed during the first three days of nutritional rehabilitation. Higher initial caloric intake is supported by evidence. Continuous nasogastric tube feeding was proposed for patients with a BMI < 12 kg/m2. We monitor hypoglycemia for 72 h. Continuous cardiac monitoring for bradycardia <30 BPM and systematic phosphate supplementation should be considered. Developing protocols is necessary to improve standardization of care. We provide an example of an inpatient admission protocol for adolescents with severe AN.