Water intoxication in anorexia nervosa: a case report

Area of Science:

• Clinical Case Reports
• Eating Disorders Research
• Neuroendocrinology

Background:

• Anorexia nervosa (AN) is a complex eating disorder characterized by severe food restriction and distorted body image.
• Water intoxication, though rare, can be a life-threatening complication in patients with AN.
• Understanding the specific risk factors for abnormal drinking behaviors in AN is crucial for effective management.

Observation:

• A patient with a 13-year history of AN presented with severe malnutrition (BMI 8.3) requiring compulsory treatment.
• Following inpatient recovery and transition to outpatient care, the patient experienced seizures, vomiting, and electrolyte imbalances indicative of water intoxication.
• The patient admitted to consuming excessive water before weigh-ins to manipulate her weight, a habit she continued despite awareness of risks.

Findings:

• The patient's water intoxication was linked to a deliberate strategy of excessive water intake to artificially maintain a target weight.
• This case demonstrates a severe manifestation of psychogenic polydipsia in the context of chronic anorexia nervosa.
• Electrolyte disturbances, including hyponatremia, hypokalemia, and hypochloremia, were key indicators of the water intoxication episode.

Implications:

• This case underscores the importance of screening for and addressing abnormal drinking behaviors in patients with anorexia nervosa.
• Further research with larger sample sizes is necessary to elucidate the prevalence and specific risk factors for excessive water consumption in AN.
• Multidisciplinary treatment approaches should consider the psychological drivers behind such potentially dangerous compensatory behaviors.