What is the next step in assessing a 20-year-old female college athlete with severe weight loss, BMI of 16.4, bradycardia, and hypotension?

Comprehensive Assessment for Female Athlete Triad/RED-S

The next step in assessing this 20-year-old female athlete with severe weight loss, BMI of 16.4, bradycardia, and hypotension should be a comprehensive laboratory workup including complete blood count, comprehensive metabolic panel, thyroid function tests, and an ECG to evaluate for cardiac complications. 1

Initial Laboratory Assessment

The patient presents with classic signs of Female Athlete Triad/Relative Energy Deficiency in Sport (RED-S) with severe manifestations:

• Significant weight loss over 6 months
• Severely low BMI (16.4 kg/m²)
• Bradycardia (pulse 52 bpm)
• Hypotension (BP 84/54 mmHg)

The following laboratory tests should be ordered immediately:

1. Complete Blood Count (CBC) - To assess for anemia, particularly iron deficiency anemia which is common in female athletes with energy deficiency 2, 1

2. Comprehensive Metabolic Panel - To evaluate:

   • Electrolyte abnormalities (particularly potassium, which can affect cardiac function)
   • Blood glucose levels (hypoglycemia is common)
   • Liver and kidney function 1

3. Hormonal Assessment:

   • Estradiol, FSH, LH (to assess reproductive hormone status)
   • Thyroid function tests (TSH, free T3, free T4) - Low T3 syndrome is common in energy deficiency 2, 1

4. ECG - Critical to evaluate for:

   • QT interval prolongation (risk of arrhythmia)
   • Other cardiac abnormalities 2, 3

Cardiac Evaluation

The patient's bradycardia (pulse 52) and hypotension (84/54) represent serious cardiovascular complications that require immediate attention:

• ECG evaluation is essential as QT prolongation is common and increases risk of life-threatening arrhythmias 3, 4
• Recent research shows that rapid weight loss is an independent predictor of severe bradycardia in patients with disordered eating 5
• Structural cardiac changes including myocardial atrophy and reduced cardiac output may be present 3, 4

Risk Stratification

This patient falls into the high-risk category based on:

• BMI <16.5 kg/m² (current BMI 16.4)
• Bradycardia and hypotension
• Significant weight loss over 6 months 2

According to the Female Athlete Triad Coalition guidelines, athletes with anorexia nervosa who have a BMI <16 kg/m² should be categorically restricted from training and competition 2. This patient's BMI of 16.4 is borderline but still concerning given the cardiovascular findings.

Additional Assessments

After the immediate laboratory and cardiac evaluation:

1. Bone Health Assessment:

   • 25-hydroxyvitamin D level
   • Consider DXA scan to assess bone mineral density 1

2. Iron Studies:

   • Ferritin, iron, TIBC, and transferrin saturation 2, 1

3. Psychological Assessment:

   • Evaluate for eating disorders
   • Assess for depression, anxiety, and other psychological comorbidities 2

Management Considerations

The patient requires urgent medical attention due to cardiovascular compromise:

• Hospitalization should be considered given the severe bradycardia, hypotension, and very low BMI
• Careful refeeding must be initiated with monitoring for refeeding syndrome 6
• Cardiac monitoring during initial refeeding phase is essential 6, 4

Important Cautions

1. Do not immediately prescribe oral contraceptives as the sole treatment for amenorrhea - this is a common mistake that masks the underlying energy deficiency without addressing the root cause 1

2. Monitor for refeeding syndrome - Cardiac complications can worsen during initial refeeding due to electrolyte shifts 6

3. Recognize that good athletic performance does not rule out serious medical issues - Athletes can maintain performance despite significant physiological compromise 1

This patient requires immediate comprehensive evaluation with particular attention to cardiac status, as cardiovascular complications represent a significant mortality risk in patients with severe energy deficiency and low BMI.