Is There Cure For Night Eating Syndrome?
Date: Thursday, October 9th, 2003
Title: “The Night Eating Syndrome”
Speaker: Albert J. Stunkard, M.D., University of Pennsylvania, Philadelphia, PA
Dr. Stunkard gave an intriguing history and recent overview of the night eating syndrome in humans.
Night eating syndrome was first noted in the 1950s. An obese patient described a pattern of eating in which little was consumed in the morning and at lunch time, but the dinner meal was reported as large, and after dinner, eating continued into the night.
Additional anecdotal reports from patients seemed to suggest that this pattern of eating was common in obese patients. The prevalence of night eating is 1.5% in the general population, 7.6% and 8.9% among treatment seeking obese persons in an obesity clinic and 27% among severely obese.
Thus, the heavier one is, the greater the likelihood of night-eating syndrome.
Dr. Stunkard presented a study that looked at 40 night eaters and 40 controls. These data suggest that overall energy intake does not differ between the two groups. It is the pattern of food intake that is different.
Provisional criteria for night eating syndrome are that a patient exhibit morning anorexia, evening hyperphagia, wake at least once per night, and consume snacks throughout the night. Morning hunger levels are lower in night eaters than controls while calories eaten after 6 p.m. are greater in night eaters than controls. Night eaters also awake 1.8 times per night compared to 0.5 for the controls and 75% of times when they awake, they eat.
Psychosocial factors have been reported to differ between non-night eaters and night-eaters. Beck depression scores indicate that night-eaters are more depressed overall.
Perceived stress levels are higher in night-eaters than in controls. In addition, 75% of subjects report stress events at the onset of night-eating, while 25% report that a non-stress event was the onset.
In the “normal” eater, mood is relatively stable throughout the day, while for the night-eater, mood is highest in the morning and declines throughout the day inversely proportional to energy intake. Night eaters report more child abuse, emotional abuse, and neglect than controls. One study from Denmark reported that night-eaters reported more physical neglect as children and often show symptoms of anxiety.
Physiology between night-eaters and non-night-eaters shows fundamental differences. For example, salivary cortisol levels are higher in night-eaters than in controls. In addition to differences in physiology, sleep quality and efficiency are lower in night-eaters. Studies in mice have shed light on the sleep patterns of night eaters. When their food intake was shifted from night to day many of their circadian rhythms were disrupted, as is the case with the food intake of the night-eaters. These studies suggest that circadian rhythms are disrupted in night-eaters, compared to controls.
Night-eating syndrome has shown some improvement with certain medications. Sertraline, given at doses between 50-200 mg/day for 12 weeks, decreases the number of awakenings per night, out of bed eating, and the amount of energy consumed after dinner in night-eaters. Additional medications and treatments are being investigated.
Q. Did you validate the diet records with actual intake (in reference to the first study that Dr. Stunkard reported)?
A. No, we checked their food records with them.
Q. Do these individuals (night-eaters) have a history of insomnia?
A. They are insomniac with the disorder but don’t report insomnia before this.
Q. Do you have subject hunger reports for your studies?
A. Yes, they fill out a hunger questionnaire which shows the striking morning anorexia.
Q. Is the prevalence of night-eating equal between the sexes?
A. It is somewhat more common among women.
Q. Was the difference in cortisol levels significant throughout, or at one time point?
A. The salivary cortisol levels of the night-eaters were significantly higher.
Q. Have you interviewed relatives of pt. with night eating?
A. Yes and we have shown strong familiarity.
Q. Do you have any data looking at mood in night-eaters?
A. Yes, as noted, their general level of depression is elevated and, paradoxically gets worse in the evening.
Q. Do you know the rate of onset of sertraline?
A. Most responded within 8 weeks.
Q. Is this the first time that NE is reported in normal weights?
A. It is the first time that there has been systematic study of them.
Q. Have you looked at fat distribution in night eaters and controls?
Q. Has anybody looked at night eating in children?
A. It doesn’t exist in children.
Q. What age do people start to report night eating syndrome?
A. Early 20s.
Q. What about polysomnography?
A. Night eaters wake about 1.5 hours after going to sleep and they wake up during both REM and non-REM sleep.
Q. I suggest getting gherlin.
A. We already have. Levels are all over the map.
Q. It seems in your data with sertraline that the primary effect in kcal intake is that you limit the amount of wake periods.
A. The wake periods decrease but also the food intake at night and evening, and hunger increases in the morning.