Vortioxetine for Binge Eating Disorder

Binge-eating disorder recently included in the Diagnostic and Statistical Manual, 5th Edition, is now recognized as a serious public health problem. Binge-eating disorder is associated with obesity and psychiatric comorbidities, including depression, and may be predictive of metabolic syndrome. Many patients are undertreated despite functional impairments and personal and social difficulties leading to a poor quality of life. Binge-eating disorder is characterized by recurrent episodes of excessive food consumption accompanied by a sense of loss of control and psychological distress but without the inappropriate compensatory weight-loss behaviors of bulimia nervosa. Binge eating is seen in 23-46% of obese individuals seeking weight loss treatment and its severity relates to body mass index and predicts regain of lost weight.

Current treatments for binge eating disorder are often inadequate. Cognitive behavioral therapy has been shown to reduce binge eating but finding trained psychologists is difficult. Lisdexamfetamine was recently approved by the Food and Drug Administration for binge eating disorder but it carries risk of addiction and diversion and so will likely not be prescribed by most family physicians or psychiatrists. Other currently available medications, used off-label for binge eating disorder, include anticonvulsants, which may reduce binge eating but are often poorly tolerated. Therefore, additional clinical trials are needed to identify effective pharmacotherapies.

Consuming food is necessary for life and involves brain regions that are quite ancient in evolutionary terms. The intestinal tract itself is almost like a "second brain" in that it contains vast amounts of neurons used to transmit and process sensory information; indeed the intestinal tract contains more of the neurotransmitter serotonin than the brain itself. Peripheral signals from the body (including from the intestinal tract, but also from the blood stream - e.g. glucose levels) are transmitted to brain regions such as the hypothalamic nuclei to help regulate appetite/hunger and maintain equilibrium. Another key aspect of circuitry involved in eating involves the brain reward system, including the nucleus accumbens, which is regulated by neurotransmitters such as dopamine, opioids, noradrenaline, and serotonin. In humans, but to a lesser degree in other animals, there is also top-down control from the prefrontal cortices, which serve to regulate our behaviors and suppress our tendencies to crave rewards, and allow us to flexibly adapt our behavior rather than get stuck in repetitive habits. Thus, binge-eating most likely involves dysregulation of all three above domains regulating behavior: the primitive 'peripheral-hypothalamic' feedback system, reward circuitry, and top-down control circuitry. On a neurochemical level, binge eating may be related to dysfunction of the serotonergic, dopamine, glutamatergic, and norepinephrine systems. Thus, a medication to target binge eating needs to be multi-modal in terms of its pharmacology.