Physical Examination Findings in Anorexia Nervosa
The most critical physical examination findings in anorexia nervosa include bradycardia, hypotension, hypothermia, significant weight loss, and muscle wasting, which require immediate medical attention as they can be life-threatening. 1
Vital Signs
Cardiovascular findings:
- Bradycardia (heart rate <40 bpm) - a hallmark sign requiring urgent attention
- Hypotension (systolic BP <90 mmHg)
- Orthostatic changes in pulse and blood pressure
- Peripheral cyanosis (acrocyanosis)
Temperature abnormalities:
- Hypothermia (body temperature <36°C/96.8°F)
Anthropometric Measurements
- Significantly low body weight (BMI <17.5 kg/m²)
- Severe cases: BMI <15 kg/m²
- Extreme cases: BMI <13.5 kg/m²
- Rapid weight loss (>10% of body weight)
- Reduced arm, thigh, and calf circumferences 2
- Loss of subcutaneous fat, particularly visible in:
- Fat pads below the eyes
- Triceps and biceps areas
- Interosseous spaces between thumb and forefinger
Musculoskeletal System
- Muscle wasting, particularly noticeable in:
- Temporalis muscle
- Prominence of clavicles
- Squared rather than rounded shoulders
- Visible scapulae and ribs
- Reduced quadriceps muscle mass
- Reduced muscle strength
- Lanugo (fine, downy hair growth on body)
Skin and Appendages
- Dry skin with poor turgor
- Brittle nails
- Hair loss or thinning
- Yellow-tinged skin (carotenemia)
- Russell's sign (calluses on knuckles from self-induced vomiting)
- Dental enamel erosion (in patients with purging behaviors)
Gastrointestinal System
- Abdominal distension (paradoxical to overall emaciation)
- Delayed gastric emptying
- Constipation
- Abdominal pain
- Reduced bowel sounds
Neurological Findings
- Cognitive impairment
- Poor concentration
- Memory deficits
- Confusion
- Muscle weakness
- Peripheral neuropathy (in severe cases)
Endocrine System
- Amenorrhea in females (though no longer a diagnostic criterion)
- Delayed puberty in adolescents
- Cold intolerance
- Reduced libido
Monitoring Considerations
- Regular vital sign monitoring is essential, particularly heart rate and orthostatic measurements
- Weekly weight measurements should be conducted
- ECG monitoring for QTc prolongation
- Laboratory testing for electrolyte abnormalities
Warning Signs Requiring Immediate Medical Attention
- Heart rate <40 bpm
- Systolic blood pressure <90 mmHg
- Body temperature <36°C
- Syncope or pre-syncope
- Significant electrolyte abnormalities
- Severe muscle wasting
The physical examination findings in anorexia nervosa reflect the body's adaptation to starvation and malnutrition. While laboratory tests may appear normal even in severely malnourished patients 3, the physical examination often reveals the true severity of the condition. A thorough physical assessment is crucial for determining the appropriate level of care and monitoring the patient's response to treatment.