Rapid refeeding in anorexia nervosa: A dialectic balance

The incidence of refeeding syndrome and the nutrition management of severely malnourished inpatients with eating disorders: An observational study

OBJECTIVE

Nutritional rehabilitation and weight restoration are often critical for the treatment of eating disorders (ED), yet are restricted by the potential risk of refeeding syndrome (RFS). The primary objective was to determine the incidence of RFS. Secondary objectives were to explore predictive factors of RFS and describe its impact on treatment goals for patients with ED.

METHOD

This retrospective observational study reviewed the nutrition management for patients admitted to a quaternary hospital for ED treatment from 2018 to 2020. Data were collected during the first 4 weeks of admission and included anthropometry, energy prescription, incidence and severity of RFS, and electrolyte and micronutrient prescription. Outcomes included incidence of RFS, energy prescription and advancement, and weight change.

RESULTS

Of 423 ED admissions, 217 patients (median [interquartile range, IQR] age 25 [21-30.5] years; 210 [97%] female) met inclusion criteria. Median (IQR) body mass index (BMI) on admission was 15.5 (14.1-17.3) kg/m2 . The mean (standard deviation) length of admission was 35 (7.3) days. Median (IQR) initial energy prescription was 1500 (930-1500) kcal/day. Seventy-three (33%) patients developed RFS; 34 (16%) mild, 27 (12%) moderate, and 12 (5%) severe. There was no association between RFS severity and admission BMI, energy prescription, or prescription of prophylactic electrolytes or micronutrients. Lower admission weight was associated with RFS (odds ratio 0.96, 95% confidence interval [0.93-1.00], p = .035). Less than half of the participants met the weight gain target (>1 kg per week) in the first 3 weeks of admission.

DISCUSSION

The incidence of severe RFS was low in this cohort and was associated with lower admission weight.

PUBLIC SIGNIFICANCE

This study is one of the largest studies to utilize consensus-defined criteria to diagnose RFS among adult patients admitted for treatment of an ED. This population is still considered to be at risk of RFS and will require close monitoring. The results add to the growing body of research that restriction of energy prescription to prevent RFS may not require the level of conservatism traditionally practiced.

Psychologically informed care of patients with anorexia nervosa on an acute medical ward

Anorexia nervosa is a challenging and highly distressing illness associated with significant and often debilitating symptoms that affect the person's physical and mental well-being, as well as their wider social networks. Although some patients can make important steps in their recovery in the community, many will become significantly unwell and require medical stabilisation and refeeding in an acute medical ward as a result of significant weight loss. This article describes some of the challenges experienced by adult nurses when caring for patients with anorexia nervosa on acute medical wards and explores how the patient's distress may manifest and complicate the recovery process. The article also discusses the principles of psychologically informed care and therapeutic interactions that nurses can use to promote recovery and ensure optimal practice.

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.

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.