Tracking the Night Eating Syndrome

The hidden nature of night eating syndrome, or NES, is one reason this disorder is frequently overlooked by health care professionals and patients alike. Although the syndrome of morning anorexia, evening hyperphagia and/or insomnia was first reported by Stunkard and his colleagues at least 60 years ago, lack of a standard definition has impeded recognition of NES comparison and comparison of study results.

The DSM-5 has helped somewhat by listing three main diagnostic criteria for NES: (1) recurrent episodes of night eating, shown by eating after awakening from sleep or by excessive eating after the evening meal; (2) awareness of those eating episodes; and (3) significant distress or impairment brought on by the disorder. Another disorder, sleep-related eating disorder, or SRED, is also characterized by recurrent episodes of involuntary eating or drinking during sleep, but is considered as a type of parasomnia, or primary sleep disorder in which physiology or behaviors are affected by sleep, the stage of sleep, or the transition from sleeping to waking, rather than to an eating disorder.

A new instrument designed to detect NES

Suat Kucukgoncu, MD, and colleagues at Yale University recently evaluated the assessment and management of NES (Neuropsychiatr Dis Treat. 2015; 11:751). The authors note that although the Night Eating Questionnaire (NEQ) is widely used to detect NES, it often yields false-positive results in selected groups, such as obese patients and those who have had gastric bypasses, and thus a second interview component may be helpful. The Night Eating Syndrome History and Inventory is one useful addition to existing tests. This semi-structured interview also includes questions about the history of night eating symptoms, the amount of food eaten per day, sleep patterns, mood symptoms, life stressors, weight and diet history, and previous treatment for NES.

A multitude of treatment approaches

Treatment approaches for NES have included pharmacologic agents, cognitive behavioral therapy, light therapy, and muscle relaxation therapy, according to Dr. Kucukgoncu and his coauthors. The serotonin system was a natural target for pharmacologic treatment, and just as for bulimia nervosa, clinical trials have primarily involved antidepressants, particularly the selective serotonin re-uptake inhibitors (SSRIs) sertraline and escitalopram.

Uncontrolled studies with sertraline showed that the SSRI improved NES symptoms, mood, and quality of life. Subsequently, an 8-week blinded, randomized trial of sertraline significantly improved both NES symptoms and quality of life (Am J Psychiatry. 2006; 67:1568). Caloric intake after the evening meal also decreased in patients receiving sertraline compared to those receiving a placebo. A randomized trial with escitalopram showed improvements in night eating symptoms as well as modest weight loss, but the active drug results were not significantly better than with placebo (Eat Behav. 2013; 14:199).

Topiramate, a glucocerebrosidase (GBA) agonist and glutamate antagonist, has also been beneficial for treating NES. [See “Update,” earlier in this issue.] However, in one study, once the drug was discontinued, symptoms of NES returned (Sleep Med. 2003; 4:243). Because to date there are no guidelines or data on the duration of the therapeutic benefit of medications for NES, Dr. Kucukgoncu and colleagues recommend that any medication be used at least 8 weeks before reaching conclusions about its effects. They also suggest considering a total treatment period of at least one year if a medication proves beneficial before determining if it is successful or unsuccessful for treating NES.

Psychological interventions

Psychological interventions have also been used with some success to treat patients with NES. In particular, Allison and colleagues have developed a cognitive behavioral therapy program for NES. During an uncontrolled CBT trial conducted in patients with NES (Am J Psychother. 2010; 64:91), 14 of 25 patients participated in 10 hours of CBT sessions over 12 weeks. CBT treatment led to significant reductions in evening hyperphagia, reduced the number of nocturnal eating episodes and total caloric intake, and diminished depressive symptoms. Interestingly, the authors noted that CBT reduced excessive eating most markedly during the night but not right after the evening meal.