Diets with high carbohydrate contents were associated with refeeding hypophosphatemia: A retrospective study in Japanese inpatients with anorexia nervosa

Inpatient treatments for adults with anorexia nervosa: a systematic review of literature

PURPOSE

Anorexia nervosa (AN) is a mental disorder for which hospitalization is frequently needed in case of severe medical and psychiatric consequences. We aim to describe the state-of-the-art inpatient treatment of AN in real-world reports.

METHODS

A systematic review of the literature on the major medical databases, spanning from January 2011 to October 2023, was performed, using the keywords: "inpatient", "hospitalization" and "anorexia nervosa". Studies on pediatric populations and inpatients in residential facilities were excluded.

RESULTS

Twenty-seven studies (3501 subjects) were included, and nine themes related to the primary challenges faced in hospitalization settings were selected. About 81.48% of the studies detailed the clinical team, 51.85% cited the use of a psychotherapeutic model, 25.93% addressed motivation, 100% specified the treatment setting, 66.67% detailed nutrition and refeeding, 22.22% cited pharmacological therapy, 40.74% described admission or discharge criteria and 14.81% follow-up, and 51.85% used tests for assessment of the AN or psychopathology. Despite the factors defined by international guidelines, the data were not homogeneous and not adequately defined on admission/discharge criteria, pharmacological therapy, and motivation, while more comprehensive details were available for treatment settings, refeeding protocols, and psychometric assessments.

CONCLUSION

Though the heterogeneity among the included studies was considered, the existence of sparse criteria, objectives, and treatment modalities emerged, outlining a sometimes ambiguous report of hospitalization practices. Future studies must aim for a more comprehensive description of treatment approaches. This will enable uniform depictions of inpatient treatment, facilitating comparisons across different studies and establishing guidelines more grounded in scientific evidence.

LEVEL OF EVIDENCE

Level I, systematic review.

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.

Comparison of metabolic parameters between oral and total parenteral nutrition in children with severe eating disorders

BACKGROUND

This study investigated changes of lipid parameters in children with severe eating disorders during refeeding in order to explore the optimal timing for lipid preparation administration.

METHODS

We prospectively assessed the physical conditions of patients with eating disorders after the start of nutrition therapy. The assessments were performed at admission and at 2 and 4 weeks. Lipid metabolism was assessed based on triglyceride (TG), total cholesterol (TC), and free carnitine (FC) levels, as well as acylcarnitine/free carnitine (AC/FC) ratio.

RESULTS

A total of 18 patients were included. Of these, 12 and 6 received an oral diet (OD group) and total parenteral nutrition (TPN group), respectively. The mean body mass indexes at hospital admission were 12.8 kg/m2 in the OD group and 12.7 kg/m2 in the TPN group. At 2 weeks after the start of refeeding, TC, TG, and AC/FC levels were significantly lower in the TPN group than in the OD group. Other blood test results did not show any significant differences between the two groups.

CONCLUSIONS

Fat-free glucose-based nutrition promoted lipid metabolism over a 2-week period after the start of refeeding, suggesting that balanced energy and lipid intake are essential, even in TPN.

Comparison of metabolic parameters between oral and total parenteral nutrition in children with severe eating disorders

BACKGROUND

This study investigated changes of lipid parameters in children with severe eating disorders during refeeding in order to explore the optimal timing for lipid preparation administration.

METHODS

We prospectively assessed the physical conditions of patients with eating disorders after the start of nutrition therapy. The assessments were performed at admission and at 2 and 4 weeks. Lipid metabolism was assessed based on triglyceride (TG), total cholesterol (TC), and free carnitine (FC) levels, as well as acylcarnitine/free carnitine (AC/FC) ratio.

RESULTS

A total of 18 patients were included. Of these, 12 and 6 received an oral diet (OD group) and total parenteral nutrition (TPN group), respectively. The mean body mass indexes at hospital admission were 12.8 kg/m2 in the OD group and 12.7 kg/m2 in the TPN group. At 2 weeks after the start of refeeding, TC, TG, and AC/FC levels were significantly lower in the TPN group than in the OD group. Other blood test results did not show any significant differences between the two groups.

CONCLUSIONS

Fat-free glucose-based nutrition promoted lipid metabolism over a 2-week period after the start of refeeding, suggesting that balanced energy and lipid intake are essential, even in TPN.

Vitamin D and hypophosphatemia in patients with anorexia nervosa and avoidant/restrictive food intake disorder: a case control study

BACKGROUND

Refeeding hypophosphatemia (RH) is a common complication of nutritional restoration in malnourished individuals, yet clear risk stratification remains elusive. Individuals with anorexia nervosa (AN) and avoidant/restrictive food intake disorder (ARFID) may be deficient in vitamin D, an important component of dietary phosphorus absorption in the gut. The relationship between vitamin D and RH in AN and ARFID is unknown. Therefore, the aims of this study were to (1) report rates of low serum 25-hydroxy vitamin D and RH in AN and ARFID; (2) describe associations between phosphorus and variables associated with RH identified in extant literature; (3) examine the relationship between 25-hydroxy vitamin D and RH and (4) investigate moderation by vitamin D between variables of interest and phosphorus level.

METHOD

Analyses included retrospective chart review of 307 individuals admitted to the ACUTE Center for Eating Disorders and Severe Malnutrition with a diagnosis of AN or ARFID. Variables of interest included admission laboratory values (vitamin D level, comprehensive metabolic panel, hemoglobin, point-of-care blood glucose), anthropometric measures (weight, body mass index [BMI], % ideal body weight [IBW]), age, duration of illness, length of stay, feeding method, and serum phosphorus nadir. Pearson and Spearman rank correlation, one-way ANOVA, and regression analyses were used to determine the relationship between variables and serum phosphorus.

RESULTS

Over 1/3 of the sample (35.3%) had serum phosphorus levels ≤ 2.9 mg/dL. There were no significant differences between groups in phosphorus nadir (p = .17, η2 = 0.12) or hypophosphatemia (p = .16, ϕc = 0.11). Thirty-five (35%) of individuals with ARFID were either deficient or insufficient in vitamin D, compared to 29% of individuals with AN. Individuals with AN had significantly higher mean vitamin D levels compared to those with ARFID (p = .03; η2 = 0.015). Nadir phosphorus showed a positive association with weight, BMI, %IBW, potassium, and calcium on admission, and a negative association with length of stay, hemoglobin, and total number of tube-fed days. Higher levels of 25-hydroxy vitamin D moderated the relationship between serum phosphorus nadir and weight on admission (p = .0004).

CONCLUSION

Individuals diagnosed with ARFID are as nutritionally fragile as those with AN regarding vitamin D and RH. The negative feedback loop involving vitamin D that maintains phosphorus homeostasis may play a role in the development of RH in AN and ARFID.

Vitamin D and Hypophosphatemia in Patients with Anorexia Nervosa and Avoidant/Restrictive Food Intake Disorder: A Case Control Study

Background

Refeeding hypophosphatemia (RH) is a common complication of nutritional restoration in malnourished individuals, yet clear risk stratification remains elusive. Individuals with anorexia nervosa (AN) and avoidant/restrictive food intake disorder (ARFID) may be deficient in vitamin D, an important component of dietary phosphorus absorption in the gut. The relationship between vitamin D and RH in AN and ARFID is unknown. Therefore, the aims of this of this study were to 1) describe the prevalence of low serum 25-hydroxy vitamin D levels and RH in AN and ARFID 2) report associations between nadir phosphorus level and variables associated with RH in extant literature and 3) examine the relationship between 25-hydroxy vitamin D levels and serum phosphorus nadir in AN and ARFID.

Method

Analyses included retrospective chart review of 307 individuals admitted to the ACUTE Center for Eating Disorders and Severe Malnutrition with a diagnosis of AN or ARFID. Variables of interest included admission laboratory values (vitamin D level, comprehensive metabolic panel, hemoglobin, point-of-care blood glucose), anthropometric measures (weight, body mass index [BMI], % ideal body weight [IBW]), age, duration of illness, length of stay, feeding method, and serum phosphorus nadir. Pearson and Spearman rank correlation, one-way ANOVA, and regression analyses were used to determine the relationship between variables and serum phosphorus.

Results

Over 1/3 of the sample (35.3%) had serum phosphorus levels ≤ 2.9 mg/dL. There were no significant differences between groups in phosphorus nadir (p = .17, η2 = 0.12) or hypophosphatemia (p = .16, ϕc = 0.11); 44% of individuals with ARFID and 33% of individuals with AN had hypophosphatemia. Nadir phosphorus showed a positive association with weight, BMI, %IBW, potassium, and calcium on admission, and a negative association with length of stay, hemoglobin, and total number of tube-fed days. Higher levels of 25-hydroxy vitamin D moderated the relationship between serum phosphorus nadir and weight on admission (p = .0004).

Conclusion

Individuals diagnosed with ARFID are as nutritionally fragile as those with AN regarding vitamin D and RH. The negative feedback loop involving vitamin D that maintains phosphorus homeostasis may play a role in the development of RH in AN and ARFID.

Refeeding Hypophosphatemia in Hospitalized Adolescents With Anorexia Nervosa

Refeeding hypophosphatemia in hospitalized adolescents with anorexia nervosa is correlated with degree of malnutrition, with a high index of suspicion for severely malnourished patients (<70% median body mass index). Weight history (greater magnitude or rate of weight loss prior to admission) regardless of presentation weight has also been associated with lower serum phosphate. Higher energy meal-based refeeding starting at 2,000 kcal has not been shown to be associated with higher rates of refeeding hypophosphatemia than the traditional standard of care, lower energy refeeding. Further research is needed to identify risk factors for refeeding hypophosphatemia and develop optimal delivery methods (oral vs. enteral), macronutrient content, and electrolyte replacement strategies to optimize weight gain without increasing the risk for refeeding hypophosphatemia.

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

BACKGROUND

The nutritional rehabilitation of malnourished patients hospitalised with anorexia nervosa is essential. The provision of adequate nutrition must occur, while simultaneously, minimising the risk of refeeding complications, such as electrolyte, metabolic, and organ dysfunction. The aim of this study was to compare the efficacy and safety of an iso-caloric lower carbohydrate/high fat enteral formula (28% carbohydrate, 56% fat) against a standard enteral formula (54% carbohydrate, 29% fat).

METHODS

Patients (aged 15-25 years) hospitalised with anorexia nervosa were recruited into this double blinded randomised controlled trial. An interim analysis was completed at midpoint, when 24 participants, mean age 17.5 years (± 1.1), had been randomly allocated to lower carbohydrate/high fat (n = 14) or standard (n = 10) feeds.

RESULTS

At baseline, there was no significant difference in degree of malnutrition, medical instability, history of purging or serum phosphate levels between the two treatment arms. A significantly lower rate of hypophosphatemia developed in patients who received the lower carbohydrate/high fat formula compared to standard formula (5/14 vs 9/10, p = 0.013). The serum phosphate level decreased in both feeds, however it decreased to a larger extent in the standard feed compared to the lower carbohydrate/high fat feed (standard feed 1.11 ± 0.13 mmol/L at baseline vs 0.88 ± 0.12 mmol/L at week 1; lower carbohydrate/high fat feed 1.18 ± 0.19 mmol/L at baseline vs 1.06 ± 0.15 mmol/L at week 1). Overall, serum phosphate levels were significantly higher in the lower carbohydrate/high fat feed compared with standard feed treatment arm at Week 1 (1.06 ± 0.15 mmol/L vs 0.88 ± 0.12 mmol/L, p < 0.001). There was no significant difference in weight gain, number of days to reach medical stability, incidence of hypoglycaemia, or hospital length of stay.

CONCLUSIONS

The results of this study indicate that enteral nutrition provided to hospitalised malnourished young people with anorexia nervosa using a lower carbohydrate/high fat formula (28% carbohydrate, 56% fat) seems to provide protection from hypophosphatemia in the first week compared to when using a standard enteral formula. Further research may be required to confirm this finding in other malnourished populations.

TRIAL REGISTRATION

ANZCTR, ACTRN12617000342314. Registered 3 March 2017, http://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12617000342314.

Anorexia Nervosa-What Has Changed in the State of Knowledge about Nutritional Rehabilitation for Patients over the Past 10 Years? A Review of Literature

Anorexia nervosa (AN) is a psycho-metabolic disorder with a high risk of somatic complications such as refeeding syndrome (RFS) and carries the highest mortality rate of all psychiatric illnesses. To date, the consensus on the care for patients with AN has been based on recommendations for a combination of alimentation and psychotherapy. It is important to establish an initial caloric intake that will provide weight gain and minimize the risk of complications in the treatment of undernourished patients. Research over the past few years suggests that current treatment recommendations may be too stringent and should be updated. The aim of this paper is to systematize the current reports on nutritional rehabilitation in AN, to present the results of studies on the safe supplementation of patients and its potential impact on improving prognosis and the healing process. This review of literature, from 2011-2021, describes the changing trend in the nutritional protocols used and the research on their efficacy, safety, and long-term effects. In addition, it presents previous reports on the potential benefits of introducing vitamin, pro-and prebiotic and fatty acid supplementation.

Introduction to a special issue on eating disorders in Asia

OBJECTIVE

It is our pleasure to introduce a special issue of the International Journal of Eating Disorders on eating disorders (EDs) in Asia.

METHOD

We received such a robust response to the special edition that we were able to fill two issues. Contributions focused on seven main themes: (1) prevalence, (2) time trends, (3) healthcare systems, (4) treatment, (5) risk factors, (6) assessment, and (7) orthorexia.

RESULTS

New prevalence and time trend data from China, Iran, Singapore, Japan, and Taiwan suggest that EDs are increasingly common in Asia but are not always detected in healthcare settings. Only a minority of individuals with EDs in Singapore receive treatment, and psychosocial treatment and prevention interventions that are evidence-based in the West may require cultural adaptation before they can be fully implemented in Japan, Singapore, China, and South Korea. Psychological risk factors for EDs are more similar than different in Iran, India, Japan, and China, but biological risk factors are understudied across the continent. Psychometrically sound assessment tools are available in many Asian languages.

DISCUSSION

We hope this special issue provides a catalyst and blueprint for global collaboration to relieve the burden of suffering of EDs in Asia and beyond.