Prevalence and clinical determinants of low bone mineral density in anorexia nervosa

Psychiatric and medical comorbidities of eating disorders: findings from a rapid review of the literature

BACKGROUND

Eating disorders (EDs) are potentially severe, complex, and life-threatening illnesses. The mortality rate of EDs is significantly elevated compared to other psychiatric conditions, primarily due to medical complications and suicide. The current rapid review aimed to summarise the literature and identify gaps in knowledge relating to any psychiatric and medical comorbidities of eating disorders.

METHODS

This paper forms part of a rapid review) series scoping the evidence base for the field of EDs, conducted to inform the Australian National Eating Disorders Research and Translation Strategy 2021-2031, funded and released by the Australian Government. ScienceDirect, PubMed and Ovid/Medline were searched for English-language studies focused on the psychiatric and medical comorbidities of EDs, published between 2009 and 2021. High-level evidence such as meta-analyses, large population studies and Randomised Control Trials were prioritised.

RESULTS

A total of 202 studies were included in this review, with 58% pertaining to psychiatric comorbidities and 42% to medical comorbidities. For EDs in general, the most prevalent psychiatric comorbidities were anxiety (up to 62%), mood (up to 54%) and substance use and post-traumatic stress disorders (similar comorbidity rates up to 27%). The review also noted associations between specific EDs and non-suicidal self-injury, personality disorders, and neurodevelopmental disorders. EDs were complicated by medical comorbidities across the neuroendocrine, skeletal, nutritional, gastrointestinal, dental, and reproductive systems. Medical comorbidities can precede, occur alongside or emerge as a complication of the ED.

CONCLUSIONS

This review provides a thorough overview of the comorbid psychiatric and medical conditions co-occurring with EDs. High psychiatric and medical comorbidity rates were observed in people with EDs, with comorbidities contributing to increased ED symptom severity, maintenance of some ED behaviours, and poorer functioning as well as treatment outcomes. Early identification and management of psychiatric and medical comorbidities in people with an ED may improve response to treatment and overall outcomes.

Predictors of bone mineral density in adolescents with atypical anorexia nervosa

INTRODUCTION

We aimed to evaluate the bone mineral density (BMD) z scores of adolescents with atypical anorexia nervosa (AAN) and investigate the potential predictors of low BMD risk.

MATERIALS AND METHODS

Potential factors that might have an effect on the femoral neck and lumbar spine dual energy X-ray absorptiometry data of adolescents (11-18 years) with AAN were retrospectively evaluated.

RESULTS

Among adolescents with AAN, 13 (34.2%) had a z score lower than - 1 and 25 (65.8%) had a z score equal or greater than - 1. When adolescents with a BMD score lower and higher than - 1 were compared, normal BMD group had a significantly higher mean lifetime maximum BMI (p = 0.0035). Similarly previous overweight history was significantly higher in the normal BMD group (p = 0.005). A positive correlation was found between femoral neck (p = 0.002, r: 0.546) and lumbar spine (p: 0.002, r: 0.505) z scores and lifetime maximum BMI. There was also a positive correlation between lumbar spine BMD scores and BMI at admission (p = 0.001, r: 0.540). Lumbar spine z scores and amenorrhea duration were negatively correlated (p: 0.002, r:  - 10.867).

CONCLUSION

In the adolescent period similar to AN, AAN cases are also at risk for disordered bone health. In adolescents with AAN, BMI prior to the illness was estimated to be the significant parameter for the risk of low BMD. Special attention should be paid to the bone health of adolescents with AAN, especially for those who do not have a previous overweight history.

Assessment of fracture risk in women with eating disorders: The utility of dual-energy x-ray absorptiometry (DXA)-Clinical cohort study

OBJECTIVE

Eating disorders (EDs) are associated with decreased bone mineral density (BMD) and increased fracture risk. The association between BMD and fracture risk in EDs is not well elucidated. We aimed to assess BMD in an ED cohort of patients with active disease and patients in remission, and to assess the predictive value of BMD on incidence of fractures.

METHOD

We included 344 female patients (median age 19, IQR 16; 24) referred to ED treatment. Later, patients were invited to follow-up including assessment of remission status and a dual-energy x-ray absorptiometry (DXA)-scan. Information on fractures was obtained through the Danish National Registry of Patients.

RESULTS

Patients with current anorexia nervosa (AN) had significantly lower BMD compared to controls at lumbar spine (16% lower, p < .0001), femoral neck (18% lower, p < .0001), and total hip (23% lower, p < .0001). Recovered AN patients had higher BMD compared to those with current disease (p < .0001 for all measures), but lower BMD compared to controls at lumbar spine (p < .01) and hip (p < .001). BMD did not differ between BN patients and controls. In patients with active eating disorders not otherwise specified, BMD was lower only at the total hip (p < .005). We found no association between BMD and fracture risk.

CONCLUSION

We confirm that AN is associated with low BMD, whereas BN is not. Remission is associated with higher BMD compared to patients with active AN, but a deficit remains. We found no significant association between BMD and fracture risk, challenging the benefit of the widespread use of DXA scans in young women with ED.

CLINICAL TRIAL REGISTRATION

The study is registered in ClinicalTrials.gov, number NCT00267228.

Earlier diagnosis in anorexia nervosa: better watch growth charts!

BACKGROUND

A better understanding of the healthcare pathway of children and adolescents with anorexia nervosa (AN) may contribute to earlier detection and better disease management. Here we measured and compared the symptomatic time to diagnosis (TTD) (time between the first symptoms, as reported by parents, and the diagnosis) and the auxological TTD (time between the deviation in the weight growth curve and the diagnosis).

METHODS

We performed a monocentric retrospective study including all patients age 9 years to 16 years who were hospitalized in Nantes University Hospital for AN between 2013 and 2016. We analysed the two TTDs by medical record review and growth curve investigation. TTDs were described by medians and Kaplan-Meier curves. Two profiles of patients were compared according to the kinetics of growth deviation and the occurrence of symptoms.

RESULTS

Among the 137 patients included, the median symptomatic and auxological TTDs was 7.0 months (IQR: 4.0-12.0) and 7.2 months (IQR: 2.0-18.0). TTDs were significantly different but clinically similar. For 48% of the patients, a deviation in the growth curve could have been noted at a median of 9.7 months (IQR: 3.0-18.0) before the first symptoms were reported by parents. Those patients showed significantly slower weight loss than did patients with first symptoms reported before growth deviation (weight loss rate 0.41% vs 1.90% per month, p < 0.0001).

CONCLUSIONS

Careful study of growth curves remains an essential step in detecting eating disorders, possibly allowing for earlier detection of the disease in nearly half of these patients.

Intertrochanteric fracture with low-energy trauma in a young woman with anorexia nervosa: A case report

RATIONALE

Anorexia nervosa is a chronic psychiatric disease defined by severe weight loss, due to fear of obesity, and self-imposed semi-starvation. Of the many complications following anorexia nervosa, low bone mineral density (BMD) is a significant risk factor for fractures. Anorexia nervosa is associated with higher risk of incident fracture in females across all age groups, and in males >40 years old. Sites at highest risk of fracture include the hip/femur and pelvis in females, and vertebrae in males with anorexia nervosa.

PATIENT CONCERNS

A 29-year-old woman known to have suffered from anorexia nervosa 15 years ago visited the emergency department due to right hip pain after falling while getting out of a taxi. During the period of anorexia nervosa, she had a body mass index (BMI) of 14.06 kg/m (weight, 36 kg; height, 1.60 m) and suffered from amenorrhea. At the time of presentation, she had a BMI of 19.53 kg/m (weight, 50 kg; height, 1.60 m) and had regular menstrual periods, indicating clinical recovery from anorexia nervosa.

DIAGNOSES

Plain radiography, computed tomography, and bone scintigraphy revealed AO 31-A2.2 type right hip proximal femur intertrochanteric fracture. The BMD showed a T score of -3.9 in the hip and -3.6 at the lumbar level, indicating severe osteoporosis.

INTERVENTIONS

Osteosynthesis was performed with proximal femoral nail antirotation (PFNA) and wiring.

OUTCOMES

There were no specific symptoms, such as trauma or infection, during postoperative rehabilitation and postoperative management, and she was discharged after 2 weeks. After 1 year of follow-up at our outpatient clinic, she had no complications.

LESSONS

Here, we describe an unusual case of unilateral femoral intertrochanteric fracture that occurred after clinical recovery from anorexia nervosa. This case indicated that the risk of fracture remains even after recovery of BMI. We propose that women who have clinically recovered from anorexia nervosa should be advised to undergo annual osteodensitometric analyses after consulting with specialists in other areas (psychiatry, endocrinology, eating disorders).

Bilateral Simultaneous Femoral Neck Stress Fracture Despite Clinical Recovery from Anorexia Nervosa: A Case Report

CASE

A 38-year-old woman who had returned to sports activity (running) after having clinically recovered from anorexia nervosa presented with a bilateral femoral neck stress fracture that was treated with bilateral hip osteosynthesis.

CONCLUSION

Although exercise is usually considered to be beneficial for health, heavy exercise (such as running) after recovery from anorexia nervosa may be associated with an increased risk of fracture.

Bone metabolism in anorexia nervosa and hypothalamic amenorrhea

Anorexia nervosa (AN) and hypothalamic amenorrhea (HA) are states of chronic energy deprivation associated with severely compromised bone health. Poor bone accrual during adolescence followed by increased bone loss results in lifelong low bone density, degraded bone architecture, and higher risk of fractures, despite recovery from AN/HA. Amenorrhea is only one of several compensatory responses to the negative energy balance. Other hypothalamic-pituitary hormones are affected and contribute to bone deficits, including activation of hypothalamic-pituitary-adrenal axis and growth hormone resistance. Adipokines, particularly leptin, provide information on fat/energy stores, and gut hormones play a role in the regulation of appetite and food intake. Alterations in all these hormones influence bone metabolism. Restricted in scope, current pharmacologic approaches to improve bone health have had overall limited success.

Vitamin D status in anorexia nervosa: A meta-analysis

OBJECTIVE

In anorexia nervosa (AN), osteoporosis and osteopenia are common, which have been associated with low circulating levels of vitamin D (VitD) in other settings. We aimed to meta-analyze cross-sectional studies reporting on VitD parameters in patients with AN and healthy controls (HCs).

METHOD

Electronic PubMed search from database inception until December 31, 2013 and meta-analysis of cross-sectional studies comparing serum levels of 25-hydroxyvitamin D (25OH-D), 1,25-dihydroxyvitamin D (1,25OH-D) and dietary VitD between patients with AN and HCs, before or after VitD supplementation. We calculated random effects standardized mean differences (SMDs) ±95% confidence intervals (CIs) as effect size measures.

RESULTS

Out of 1,739 initial hits, 15 studies with a total of 927 participants (AN = 408 and HCs = 519) were meta-analyzed. In the unsupplemented state, both serum 25OH-D (studies = 4; n = 168; SMD = -0.43; 95%CI: -0.83 to -0.03; p = .03) and 1,25OH-D levels (studies = 4; n = 113; SMD = -1.06; 95%CI: -1.47 to -0.66; p < .00001) were significantly lower in AN than HCs. In AN patients treated with cholecalciferol supplementation, serum 25OH-D levels were significantly higher than in HCs (studies = 5; n = 449; SMD = 0.66; 95%CI: 0.01-1.31; p = .05). Paradoxically, despite lower 25OH-D and 1,25OH-D levels, AN patients reported similar intake of VitD compared to HCs (studies = 6; n = 314; SMD = 0.33; 95%CI: -0.16, 0.81; p = .19).

DISCUSSION

Although AN patients reported similar dietary VitD intake compared to HCs, AN patients had significantly lower 25OH-D and 1,25OH-D levels without supplementation. Conversely, supplementation with cholecalciferol fully normalized VitD serum levels. Future studies are needed to clarify the role of VitD supplementation in AN for improving bone health.

Subjective experience of sensation in anorexia nervosa

The nature of disturbance in body experience in anorexia nervosa (AN) remains poorly operationalized despite its prognostic significance. We examined the relationship of subjective reports of sensitivity to and behavioral avoidance of sensory experience (e.g., to touch, motion) to body image disturbance and temperament in adult women currently diagnosed with AN (n = 20), women with a prior history of AN who were weight restored (n = 15), and healthy controls with no eating disorder history (n = 24). Levels of sensitivity to sensation and attempts to avoid sensory experience were significantly higher in both clinical groups relative to healthy controls. Sensory sensitivity was associated with body image disturbance (r(56) = .51, p < .0001), indicating that body image disturbance increased with increased global sensitivity to sensation. Sensory sensitivity was also negatively and significantly correlated with lowest BMI (r(2) = -.32, p < .001), but not current BMI (r(2) = .03, p = .18), and to the temperament feature of harm avoidance in both clinical groups. We discuss how intervention strategies that address sensitization and habituation to somatic experience via conditioning exercises may provide a new manner in which to address body image disturbance in AN.

Factors associated with low bone density in patients referred for assessment of bone health

Background

To identify factors that predict low bone mineral density (BMD) in pediatric patients referred for dual-energy x-ray absorptiometry assessments.

Methods

This is a retrospective cohort study of 304 children and adolescents referred for dual-energy x-ray absorptiometry assessments at a tertiary care center. Outcomes included risk factors which predicted a significant low bone density for age, defined as BMD Z-score ≤ -2.0 SD. A univariate analysis involved Chi-square, Fisher’s Exact test, and analysis of variance, and multivariate logistic regression models were constructed to determine predictors of low bone mineral density.

Results

In the multivariate logistic regression model, predictors of low bone mineral density included low body mass index Z-score (odds ratio 0.52, 95% confidence interval 0.39 – 0.69), low height Z-score (OR 0.71, 95% CI 0.57 – 0.88), vitamin D insufficiency (OR 3.97, 95% CI 2.08 – 7.59), and history of bone marrow transplant (OR 5.78, 95% CI 1.00 – 33.45).

Conclusions

Underlying health problems and associated treatments can impair bone mineral accrual. We identified risk factors most predictive of low bone mineral density in subjects referred for bone density measurement. Recognition of these factors may allow for earlier assessment to maximize bone mass in at-risk children.

Osteoporosis in anorexia nervosa

Osteoporosis is common in anorexia nervosa. It places these patients at increased lifetime risk for fractures. Bone loss may never recover completely even once weight is restored. The strongest predictors of osteoporosis include low body weight and amenorrhea. Loss of bone density can occur rapidly and very early in the course of anorexia nervosa. The etiology of bone loss in the patient with anorexia nervosa is multifactorial. In addition to reduced estrogen and progesterone, excess cortisol levels and low levels of insulin growth factor (IGF-1), a correlate for bone formation, are observed. Dual energy x-ray absorptiometry screening is important to assess bone density. However, successful treatments to reverse bone loss, in those with anorexia nervosa, are lacking. Early diagnosis and treatment of anorexia nervosa are paramount to prevent initial weight loss and subsequent loss of bone.