Capacity assessment in a patient with anorexia nervosa
A 22-year-old woman with anorexia nervosa (BMI 13.5) is admitted to the medical ward with bradycardia (heart rate 45 bpm), hypothermia, and electrolyte imbalance. She has been restricting food intake and exercising excessively for months. She refuses nasogastric feeding, saying, 'I don't need it; I can eat on my own.' She is alert and oriented, but her thinking is rigid and focused on weight and food. She understands that she has a low weight but denies that it is dangerous. She is not psychotic or depressed. The medical team is concerned about her risk of refeeding syndrome and cardiac arrest. They ask for a psychiatric opinion on her capacity to refuse treatment.
1. How would you assess her decision-making capacity, and what is your conclusion?
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Assessing capacity (four abilities):
- Understanding: Can she understand the information about her condition and treatment? She understands she has a low weight but may not grasp the severity and risks.
- Appreciation: Can she appreciate the consequences of her decision? She denies that her low weight is dangerous, which suggests impaired appreciation.
- Reasoning: Can she reason about the risks and benefits? Her thinking is rigid and dominated by anorexia, likely impairing her ability to weigh risks.
- Choice: Can she communicate a choice? Yes, she refuses.
Conclusion: She likely lacks capacity to refuse treatment because she does not appreciate the seriousness of her condition and cannot reason objectively. Anorexia nervosa can impair decision-making capacity, especially when severely underweight.
Key point: Capacity is decision-specific. She may have capacity for other decisions but not for this one. The assessment should be documented. If she lacks capacity, treatment can be given under mental health legislation or best interests, depending on jurisdiction. Involve family and legal team.
2. What are the ethical and legal considerations in treating her without consent?
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Ethical considerations:
- Beneficence and non-maleficence: Treatment is necessary to prevent serious harm or death.
- Autonomy: Respecting autonomy is important, but when capacity is impaired, paternalistic intervention may be justified.
- Least restrictive option: Use the least restrictive means necessary, e.g., start with oral feeding and close monitoring before considering nasogastric feeding.
- Best interests: Act in her best interests, considering her values and wishes expressed when well.
Legal considerations:
- Mental health legislation: In many jurisdictions, anorexia nervosa can be treated under mental health law if it is considered a mental disorder and there is risk to life. However, laws vary; in some places, it is treated under general medical law (best interests).
- Informed consent: If she lacks capacity, consent can be obtained from a surrogate or under legal authority.
- Advance directives: Check if she has any.
- Documentation: Clearly document capacity assessment and rationale for treatment.
- Involve family: Seek their support, but confidentiality must be respected.
Plan:
- Conduct formal capacity assessment and document.
- If lacking capacity, proceed with necessary treatment under appropriate legal framework (e.g., Mental Health Act or guardianship).
- Use multidisciplinary team approach, including dietitian, physician, and psychiatrist.
- Monitor for refeeding syndrome closely.
- Consider involving an ethics committee if conflict arises.
Key point: Anorexia nervosa is a serious mental illness with high mortality; treatment refusal due to impaired capacity is a common ethical dilemma.