Anorexia nervosa is one of the most severe and complex eating disorders seen in mental health and psychiatric care. It is characterized by an intense fear of weight gain, distorted body image, and restrictive eating patterns that lead to severe malnutrition and life-threatening complications. This condition has the highest mortality rate of all mental health disorders, primarily due to suicide and severe medical complications.
For nurses, healthcare providers, and students preparing for NCLEX, HESI, and ATI exams, understanding anorexia nervosa is critical. This article provides an in-depth overview of pathophysiology, risk factors, clinical features, diagnostic criteria, treatment strategies, and nursing interventions—alongside exam-focused tips.
Pathophysiology of Anorexia Nervosa
Anorexia nervosa is a psychiatric eating disorder that involves a distorted body image and an irrational fear of being overweight, even when the patient is severely underweight.
Key Risk Factors
- Adolescent females are most commonly affected.
- Psychological stressors such as perfectionism, low self-esteem, and family pressure increase risk.
- Cultural influences, particularly in societies that glorify thinness, play a major role.
- Genetic and neurobiological factors also contribute.
Mortality Rate Concern
Anorexia nervosa is the deadliest psychiatric disorder, with the highest mortality due to suicide and severe medical complications like cardiac arrhythmias, electrolyte imbalance, and organ failure.
Signs and Symptoms of Anorexia Nervosa
Early Symptoms
- Persistent restriction of food intake.
- Obsessive calorie counting and dieting.
- Excessive exercise despite fatigue.
- Social withdrawal and irritability.
Severe Symptoms (Exam Focus)
According to the infographic and NCLEX guidelines, six hallmark clinical features are associated with anorexia nervosa:
1. Extreme weight loss
- Body weight less than 75% of expected weight or 25% below normal (NCLEX tip).
2. Fluid & Electrolyte Imbalance
- Hypokalemia (K+ < 3.5 mEq/L), leading to cardiac arrhythmias.
3. Lanugo
- Growth of fine, thin body hair as a physiological response to extreme malnutrition.
4. Amenorrhea
- Absence of menstruation due to low body fat and hormonal imbalance.
5. Cold Intolerance
- Inability to maintain body temperature due to low metabolic reserve.
6. Low Vitals
- Hypothermia, hypotension, and bradycardia (HR < 60 bpm).
Diagnostic Considerations
A patient with anorexia nervosa typically presents with:
- Distorted perception of body weight (seeing themselves as overweight despite being underweight).
- Severe weight loss with BMI far below normal.
- Vital sign instability (low HR, low BP, low temp).
- Electrolyte disturbances such as hypokalemia.
HESI Nursing Exam Insight
- A serum potassium level of 2.6 mEq/L is a critical finding that warrants hospitalization.
- Physical findings like lanugo, irregular heart rate, and very low pulse rate confirm anorexia nervosa in adolescent females.
Treatment of Anorexia Nervosa
Outpatient vs. Inpatient Care
- Most cases are treated in outpatient clinics with structured support.
- Hospitalization is required if the patient’s body weight falls below 75% of ideal or if there are severe electrolyte imbalances, cardiac complications, or suicidal ideation.
Priority Short-Term Goals
- Increase caloric intake for gradual, safe weight gain.
- Provide one-on-one supervision during feeding to prevent food avoidance or purging.
Long-Term Treatment Goals
- Restore a healthy relationship with food and body image.
- Address underlying psychiatric disorders such as anxiety, depression, or OCD.
- Establish long-term relapse prevention strategies.
Nursing Care for Anorexia Nervosa Patients
Acute Care Setting (Admitted for Malnutrition)
According to NCLEX tips, nursing care should include:
- Strict nutritional recording – monitoring protein and caloric intake.
- Supervision during meals – staying with the client during and 1 hour after meals.
- Morning weights – daily measurements before oral intake.
- Trigger identification – helping the patient recognize emotional and situational triggers.
- Exercise restriction – no exercise until safe body weight is restored.
Communication & Psychosocial Support
- Encourage progress with positive reinforcement toward healthy weight.
- Use cognitive behavioral approaches to challenge distorted thoughts.
- Involve family therapy when appropriate.
- Reinforce the principle of “progress over perfection.”
Exam-Focused NCLEX/HESI/ATI Tips
NCLEX Key Points
- Hospitalization if weight < 75% of ideal.
- Amenorrhea is a common sign due to starvation and hormonal suppression.
- Monitor for life-threatening hypokalemia (<3.5 mEq/L).
HESI Focus
- Key physical findings: lanugo, bradycardia, irregular HR, low potassium.
- Hospitalization criteria: serum K+ 2.6 mEq/L or lower.
ATI Focus
- Unrealistic fear of obesity is a diagnostic hallmark.
- Clients have a distorted body image despite visible underweight condition.
Long-Term Management and Recovery Strategies
Recovery from anorexia nervosa is a gradual process requiring multidisciplinary intervention.
Therapeutic Approaches
- Cognitive Behavioral Therapy (CBT): Helps restructure distorted thoughts about body weight.
- Nutritional Counseling: Involves meal planning, education, and supervised eating sessions.
- Family-Based Therapy (FBT): Particularly effective in adolescents.
- Medication: SSRIs may be used for co-existing depression or anxiety but are not first-line for anorexia itself.
Preventing Relapse
- Developing healthy coping skills for stress.
- Encouraging peer support groups for accountability.
- Ongoing psychiatric monitoring to prevent suicide risk.
Quick Reference Table
| Category | Key Details | NCLEX/HESI/ATI Tips |
|---|---|---|
| Pathophysiology | Distorted body image, fear of obesity | Adolescent females most affected |
| Mortality Risk | Highest of all psychiatric disorders | Suicide + cardiac complications |
| Severe Symptoms | <75% body weight, amenorrhea, lanugo, cold intolerance | Look for HR <60, BP low |
| Labs & Electrolytes | Hypokalemia, hypoglycemia | Hospitalize if K+ < 2.6 mEq/L |
| Short-Term Treatment | Calorie intake, supervised meals | No exercise during refeeding |
| Long-Term Treatment | CBT, nutrition, family therapy | Reinforce progress toward weight |
| Nursing Care | Strict recording, daily weights, supervision | Priority: weight restoration |
Frequently Asked Questions (FAQ)
Q1: Why is anorexia nervosa so dangerous?
Because it leads to malnutrition, electrolyte imbalances, cardiac arrest, and suicide, making it the most fatal psychiatric disorder.
Q2: What is the first nursing priority for anorexia patients?
The priority is restoring nutrition and weight through safe, supervised feeding.
Q3: Why do anorexic patients develop lanugo?
Lanugo, or fine body hair, develops as the body’s way of conserving heat due to extreme fat loss.
Q4: When should a patient with anorexia be hospitalized?
Hospitalization is required when weight is below 75% of ideal or when there are severe complications like hypokalemia.
Q5: What is the role of family in anorexia recovery?
Family-based therapy improves recovery rates by involving parents and caregivers in structured meal supervision and emotional support.
