Capacity, refusal and family pressure in an inpatient with anorexia nervosa
A 26-year-old woman with a 9-year history of anorexia nervosa (BMI 13.8, weight 38 kg, height 1.66 m) is admitted after a syncopal episode. Potassium 2.9 mmol/L, magnesium 0.62 mmol/L, phosphate 0.71 mmol/L, heart rate 44, QTc 470 ms. She is alert, engages in conversation, and can explain that she understands she may die, that she does not want to die, and that she nevertheless refuses nasogastric feeding and refuses to be weighed. She says her parents 'will just have to accept it'. She can recite the risks of refeeding but says 'I'd rather be thin than safe'. Her parents are distressed and demand that she be fed 'against her will'. The team asks you to assess capacity and advise on management.
1. Assess decision-making capacity and explain your reasoning.
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Capacity is decision-specific and time-specific. I would assess it for the specific decisions in front of her - consent to NG feeding and to monitoring - using a structured framework: understand, retain, weigh, and communicate.
Understand: she can describe the proposed intervention and its purpose, and the consequences of refusal, including death. Retain: she can hold and repeat the information within the interview. Communicate: she expresses a clear and consistent choice. The crux is weighing: capacity does not require the 'right' decision, and an unwise or risky choice is not itself evidence of incapacity. However, if her reasoning is dominated by illness-driven values - for example, if she cannot use the information about risk in her own deliberation, or treats weight as the only relevant good and cannot weigh survival against it - that may amount to an inability to weigh. I would probe this explicitly: ask her to compare options, explain what would change her mind, and explore whether her values are egosyntonic or driven by the disorder. Document the specific questions and answers, not just a conclusion.
If she can weigh, she has capacity and treatment refusal must be respected, with harm minimisation, close observation and a clear escalation plan. If she cannot, she lacks capacity for these decisions and treatment can proceed in her best interests under the relevant mental health or guardianship legislation, with the least restrictive option and independent review. Either way, the answer is not decided by her BMI or by her parents' wishes.
2. Outline the medical and ethical management plan, including the refeeding risk.
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Medically she is high risk: BMI 13.8, hypokalaemia, hypomagnesaemia, bradycardia, QT prolongation and borderline-low phosphate - a picture that predicts refeeding syndrome. Correct electrolytes before and during feeding, give thiamine, and start feeding slowly (for example 10-15 kcal/kg/day, roughly 400-600 kcal/day, advanced gradually) with daily phosphate, magnesium, potassium and fluid monitoring, especially in the first week. Continuous cardiac monitoring is reasonable given bradycardia and QT prolongation. Involve dietetics and a physician; consider a high-dependency setting if NG feeding proceeds.
Ethically, balance autonomy, beneficence and non-maleficence. If she lacks capacity, use the least restrictive effective intervention, involve her in decisions as far as possible, and document best-interests reasoning. If she has capacity, respect refusal but offer a negotiated plan (oral supplements, agreed monitoring, safety contract) and set clear thresholds at which the team will reassess capacity or escalate under the Mental Health Act, since capacity can fluctuate with starvation and metabolic state. Address the parents' request with empathy but explain that their consent is not the legal basis for treatment of a capacitous adult; offer them support and family work. Record the discussion, the legal framework used, and the review date.