Eating Disorders in Children and Adolescents

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management | References

Definition

Eating disorders are serious mental health conditions characterised by abnormal eating behaviours and a preoccupation with food, weight, and body image. In children and adolescents, the most common eating disorders include Anorexia Nervosa, Bulimia Nervosa, Binge Eating Disorder (BED), and Avoidant/Restrictive Food Intake Disorder (ARFID). These disorders can lead to significant physical, emotional, and social impairment, as well as life-threatening complications.

Aetiology

Eating disorders arise from a complex interplay of genetic, biological, psychological, and environmental factors:

• Genetics: A family history of eating disorders, depression, or anxiety increases the risk of developing an eating disorder.
• Biological factors: Hormonal changes during adolescence and imbalances in neurotransmitters (e.g., serotonin) may contribute to eating disorders.
• Psychological factors: Perfectionism, low self-esteem, anxiety, and obsessive-compulsive traits are commonly associated with eating disorders.
• Social influences: Societal pressure to conform to unrealistic body ideals, peer pressure, and exposure to media promoting thinness can contribute to body dissatisfaction and disordered eating behaviours.
• Trauma or life stressors: Experiences such as bullying, trauma, or family conflict can trigger eating disorders.

Pathophysiology

The pathophysiology of eating disorders involves a combination of genetic predisposition and environmental influences that lead to disordered thinking and behaviours related to food and body image. These behaviours can cause profound metabolic and hormonal changes, leading to malnutrition, electrolyte imbalances, and other medical complications. Key pathophysiological changes in different eating disorders include:

• Anorexia Nervosa: Restriction of food intake leads to severe weight loss, malnutrition, and hormonal disruptions (e.g., amenorrhoea in females, low testosterone in males).
• Bulimia Nervosa: Recurrent binge eating followed by compensatory behaviours (e.g., vomiting, laxative abuse) leads to electrolyte imbalances (e.g., hypokalaemia), gastrointestinal issues, and damage to teeth and oesophagus due to repeated vomiting.
• Binge Eating Disorder (BED): Recurrent binge eating without compensatory behaviours can lead to obesity, insulin resistance, and metabolic syndrome.
• Avoidant/Restrictive Food Intake Disorder (ARFID): Restricted food intake not driven by body image concerns, but rather sensory issues, fear of choking, or lack of interest in food, leading to malnutrition and growth issues.

Risk Factors

• Age: Adolescents are most at risk, but eating disorders can develop in younger children as well.
• Gender: Females are more commonly affected, but males can also develop eating disorders, especially in athletic populations.
• Family history: A family history of eating disorders or mental health conditions (e.g., depression, anxiety) increases the risk.
• Personality traits: Perfectionism, obsessive-compulsive tendencies, and low self-esteem are associated with a higher risk.
• Peer and societal pressures: Pressure to conform to societal ideals of thinness, as well as bullying or teasing about weight, can trigger eating disorders.
• Sports or activities: Participation in activities that emphasise body image (e.g., gymnastics, dance, modelling) increases the risk of disordered eating.

Signs and Symptoms

The symptoms of eating disorders vary depending on the specific type:

Anorexia Nervosa:

• Extreme weight loss or failure to maintain a healthy weight.
• Intense fear of gaining weight or becoming fat, despite being underweight.
• Distorted body image and denial of the seriousness of low body weight.
• Amenorrhoea (in females) or delayed puberty.
• Excessive exercise or food restriction.

Bulimia Nervosa:

• Recurrent episodes of binge eating followed by compensatory behaviours (e.g., vomiting, laxative use).
• Feeling out of control during binge episodes.
• Preoccupation with weight and body shape.
• Swollen salivary glands, tooth decay, or gastrointestinal issues from repeated purging.

Binge Eating Disorder (BED):

• Recurrent episodes of binge eating without compensatory behaviours.
• Eating large amounts of food in a short period of time, even when not hungry.
• Feelings of guilt or shame after binge eating.
• Weight gain and related health problems (e.g., obesity, high cholesterol).

Avoidant/Restrictive Food Intake Disorder (ARFID):

• Restrictive eating that leads to weight loss or failure to gain weight.
• Avoidance of food due to sensory issues, fear of choking, or lack of interest in eating.
• Growth delays or nutritional deficiencies.
• No preoccupation with body image or fear of weight gain (distinguishing it from Anorexia Nervosa).

Investigations

Initial assessment includes a thorough medical and psychological evaluation to diagnose the eating disorder and assess its severity. Investigations may include:

• Physical examination: Assess growth patterns, weight, and signs of malnutrition.
• Blood tests: Full blood count (FBC), electrolytes, liver and kidney function tests, and hormone levels (e.g., thyroid, oestrogen, testosterone) to assess nutritional status and potential complications.
• Bone density scan (DEXA): May be performed to assess for osteoporosis or osteopenia, especially in cases of long-term malnutrition (e.g., Anorexia Nervosa).
• Electrocardiogram (ECG): To detect any cardiac abnormalities caused by electrolyte imbalances or severe malnutrition.

Management

Treatment of eating disorders in children and adolescents involves a multidisciplinary approach that includes medical, psychological, and nutritional interventions. Early diagnosis and treatment are crucial for a successful outcome:

Psychological Therapy:

• Cognitive-behavioural therapy (CBT): The main treatment for eating disorders, helping patients challenge distorted thoughts about food, weight, and body image, and develop healthier behaviours.
• Family-based therapy (FBT): Involves the family in the treatment process to support the child's recovery, especially in younger patients.

Medical and Nutritional Support:

• Nutritional rehabilitation: A dietitian will help the child/adolescent restore healthy eating habits, normalise weight, and address any nutritional deficiencies.
• Medications: Antidepressants or antianxiety medications may be prescribed to manage coexisting mood disorders (e.g., anxiety, depression) in older adolescents.

Hospitalisation:

• In severe cases, hospitalisation may be required to address complications such as malnutrition, dehydration, or cardiac abnormalities.

Referral to Specialist Care:

• Referral to an eating disorder specialist or paediatrician is important if the child/adolescent's condition is severe or not responding to outpatient treatment.

References

1. NICE (2024). Eating Disorders: Diagnosis and Management. Available at: NICE Guidance
2. Royal College of Psychiatrists (2023). Management of Eating Disorders in Children and Adolescents. Available at: RCPsych
3. British Medical Journal (BMJ). (2022). Epidemiology and Treatment of Eating Disorders in Adolescents. Available at: BMJ