Hyperorality and Dietary Changes
Patients with bvFTD generally display changes in their dietary and eating habits. They usually eat more, with appetite for sweets or specific food, e.g., bananas or pieces of sugar. Hyperphagia may be preceded by weight loss related to obsessive use of diet pills and fiber aids, or selection of food (e.g., eating white food only), preventing a balanced diet. Food selection is specifically observed in the semantic variant of FTLD. Patients often eat greedily, which may cause choking, and with time they can start mouthing inedible objects. Changes in dietary habits may also concern drinks (alcohol, soft drinks, or water). Patients may seek to drink in secret, in a childish and clumsy manner. This behavior may become life-threatening (e.g., liver damage, diabetes, or severe hyponatremia), requiring appropriate environmental measures, such as filling wine bottles with grape juice, shutting off the water supplies when leaving the house, etc. With progression of the disease, apathy increases and patients stop looking for food and eating greedily. Ultimately they will even need to be encouraged to eat. However, hyperorality and mouthing behaviors are a durable symptom.