By Mary K. Stein, Managing Editor
Reprinted from Eating Disorders Review
July/August 2000 Volume 11, Number 4
©2000 Gürze Books
The Ninth Annual Conference of the Academy for Eating Disorders (AED), held May 4-7 in New York City, reflected the growth and accelerated pace of research into the epidemiology, clinical manifestations, and treatment of eating disorders. More than 800 registrants from the U.S. and abroad participated in 3 days packed with plenary sessions, workshops, and research presentations. A special preconference clinical teaching day preceded the general meeting.
Epidemiology of eating disorders
During the first plenary session, Dr. Ruth Striegel-Moore, Professor of Psychology at Wesleyan University and a past president of the AED, noted that the population with eating disorders is far more diverse than previously assumed and thus challenges recent views of sociocultural status, ethnicity, and eating disorders.
“The widely held view of eating disorders is that that they affect white, affluent girls or women,” she said. She added that the image of eating disorders as essentially a problem of the rich and famous has been prompted by early clinical descriptions, as in Hilde Bruch’s well-known book, The Golden Cage. It is also underscored by media portrayals of eating disorders as an affliction of models and royalty. “These images also contribute to the erroneous assumption that eating disorders are basically about wanting to be beautiful; the psychological and cultural pursuit of thinness are complex and cannot be reduced to a simple formulation of vanity run amok,” she said.
The category of eating disorders not otherwise specified (EDNOS) remains the most commonly used diagnosis for individuals presenting for treatment, said Dr. Striegel-Moore. Estimates are that more than half of all patients seeking treatment do not meet criteria for either anorexia nervosa or bulimia nervosa because the diagnostic criteria are too narrow, she said.
Socioeconomic and ethnic status
Dr. Striegel-Moore also reported that studies are showing an inverse relationship between socioeconomic level and some eating disorders. Individuals from lower socioeconomic classes are more likely than middle- or upper-class persons to experience disordered eating, she said. The relationship between eating disorders and socioeconomic status may vary by disorder, and sample groups are often too small to ensure adequate statistical power.
She also cited two major reasons that minority populations are underrepresented. First, minority women generally are less likely to seek psychiatric care than white women, regardless of the particular type of disorder. Second, recent evidence suggests that service providers are less likely to ask minority women about eating disorder symptoms.
To date, the most rigorous epidemiologic studies of eating disorders have been limited to white populations either by default (studies included geographic areas with very small minority representation) or by design (the investigators assumed that eating disorders would be too rare among non-white populations). In this country, there are no nationally representative data on the prevalence and basic demographic characteristics of eating disorders, she said.
Exposure to risk factors
Are some populations at increased risk because they have greater exposure to a particular risk factor? Dr. Striegel-Moore and colleagues identified certain risk factors in their recent study of binge-eating disorder (BED). For white women, personal vulnerability factors included high levels of anxiety and depression, a focus on, and family criticism about, weight and shape. Other factors were inadequate parenting and minimal parental affection. Among black women, extreme childhood shyness was the only personal vulnerability factor identified. Most black women had a supportive and thus protective social network.
Does ethnicity affect clinical presentation or affect the course or outcome of the eating disorder? She reported that in a study of BED, there were significant differences in the clinical presentation of black American women and white American women. The explanation was that, among black women, eating disorders began to appear about 3 years later than for white women, and the black women had fewer dieting concerns. Black women were also significantly less likely than white women to seek treatment for an eating disorder: Only 7% of the black women in the study sought treatment for their eating disorder, compared with 25% of the white women. .
One suggestion: adjust diagnostic criteria for BED
Dr. Striegel-Moore called for an adjustment of the current diagnostic criteria, particularly for BED. To permit the systematic description of eating disorders symptoms that have associated clinical features, clinicians and researchers should work together to develop a set of standard assessment measures and submit those to create a database, she said. Dr. Striegel-Moore pointed out that just such an effort is currently being spearheaded by Dr. James Mitchell, the incoming President of the AED.
Dr. Striegel-Moore told delegates that broad-based participation, including efforts by the international community, will allow clinicians to explore ethnic similarities and differences among individuals from different cultures. “We need to work to reduce barriers to access to care in order to ensure that access is not limited to one particular segment of the population,” she said.
Early influences on disordered eating.
There may be very early differences in feeding behaviors between female infants of eating disordered mothers and other infants, according to W. Stewart Agras, MD, Professor and Associate Chairman of the Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine. (Dr. Agras received the AED Research Award at the New York meeting.)
Dr. Agras told the audience at the plenary session, “We know that mothers with eating disorders have exaggerated concerns about their daughters’ weight and shapes. Also, eating disordered mothers tend to interact differently with their infants than do mothers without eating disorders. Children’s eating difficulties are related to their parents‘ weight status, eating attitudes, and behaviors, ” he said.
Dr. Agras cited a new study of preschool children with eating problems (Psychol Med 2000; 30(1):69). The results showed a strong association between children’s feeding problems and maternal eating disorders. Direct observation of the children while feeding correlated with the mother’s description of the child’s eating pattern. Mothers of children with eating disorders were more likely to have a past history of an eating disorder, including current EDNOS. In effect, these mothers seemed to be “handing on” some sort of eating disorder to their infants, Dr. Agras said.
Dr. Agras then reported the results of a community study of 200 children and their parents begun about 10 years ago in an attempt to look at early psychosocial risk factors for eating disorders (Int J Eat Disord 1999;25:375). Dr. Agras and colleagues have followed the children from birth. Forty-two of the 200 mothers had past or present eating disorders, including EDNOS. The 42 mothers with eating disorders (ED group), and 153 mothers without eating disorders and their children were studied for 5 years.
Beginning at 2 weeks of age, the researchers measured the infants’ sucking behavior in the laboratory. By 2 to 4 weeks of age, daughters of eating disordered mothers had a more “avid feeding style” than sons or the daughters of any other group; that is, they sucked much more quickly and vigorously than the other infants. Daughters of ED mothers also were much slower to wean from the bottle—almost 10 months later than the other infants. ED mothers expressed much more concern about their daughters’ eating patterns than they did for their sons. Attitudes toward daughters were driven by the mother’s own ideas about eating behaviors.
By 5 years of age, the effects of the mother’s eating behavior could also be seen. ED mothers felt their daughters and sons were more “whiney and depressed” than the daughters and sons of non-ED. ED mothers reported secretive eating and overeating by their daughters. Dr. Agras noted that when mothers reported overeating in the child, it was common to find maternal restraint and drive for thinness. Inhibited eating by the child correlated with the mother’s BMI.
In the next phase of the study, 54 males and 54 female children from the same group were interviewed for the first time. Very high levels of binge eating and purging were reported, but this was felt to be due to the fact that the children did not understand the concept of binge eating and purging. By the ages of 8 and 9, the concepts were much clearer to the children. At that time, Dr. Agras and colleagues studied dieting and negative affect. They found no differences in the frequency of any eating behavior between male and female children.
Innovations in obesity treatment
Susan Z. Yanovski, MD, Director of the Obesity and Eating Disorders Program at the National Institutes of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, reported that obesity is becoming a serious problem in the United States and has an impact on all areas of medicine.
The Cost of Obesity
- More than half of US adults are now overweight ( BMI ≥25).
- About 10% of African-American women over the age of 40 are severely obese (BMI > 40).
- Obesity is linked to more than 300,000 deaths per year, and second only to smoking as a cause of death in the US.
- Obesity leads to $99 billion in medical costs per year, and $52 billion per year in indirect medical costs.
Source: S. Yanovski, MD
The increase in weight has been most marked among children. Today, according to Dr. Yanovski, about 14% of American children are above the 95th percentile in weight. She added, “With this has come an increase in diseases that we used to see only in adults—high blood pressure, sleep apnea, and, increasingly, type 2 diabetes.”
This dramatic change over the past 15 years is due to significant lifestyle changes, including increased food intake, eating more meals outside the home, more snacking, and particularly, decreases in physical activity, she said. Children are spending much more time at sedentary activities that involve TV, video games, and computer games.
A goal: preventing childhood obesity
According to Dr. Yanovski, one goal is to help children avoid becoming overweight in the first place. One approach has been to manipulate their environment. She cited a recent study in which researchers investigated whether decreasing TV hours watching time would have an impact decreasing sedentary activities among 3rd and 4th graders (JAMA 1999;282:1561). The school-based 18-lesson, 6-month curriculum was designed to reduce the time children spent with TV, video games, and videotapes. Each family had an electronic TV time manager/alarm system that could be set for a specific number of hours per week. The goal was not to increase exercise, but to get children to spend less time in sedentary activities. At the end of 6 months, the children in the intervention group weren’t necessarily more active, but their weight gain had slowed significantly.
Dr. Yanovski noted that the percentage of mildly overweight adults, or those with BMIs of 25-30, hardly changed between 1960 and 1994. However, among obese women (defined as a BMI>30), obesity increased by16% during the two decades between 1960 to 1980, but leapt upward by 50% during the 6 years between 1988 and1994.
Good behavioral treatment can help people lose weight over the short term, she said, but because weight loss is so difficult to maintain, there is increasing interest in pharmacologic treatments to help maintain long-term weight loss. The two agents currently approved for long-term weight control in adults, sibutramine (Meridia), a serotonin and norepinephrine reuptake inhibitor, and orlistat (Xenical), which inhibits absorption of about a third of dietary fat, are only modestly effective, but can be helpful as an adjunct to a weight loss program.
Dr. Yanovski pointed out that a number of antiobesity drugs are now in Phase 2 (studies in humans) clinical trials. Among these are topiramate (Topamax), an antiseizure medication that is also used in the treatment of bipolar disorder, and bupropion (Wellbutrin), which is both an antidepressant and also available as an anti-smoking medication (Zyban). Eli Lilly is now investigating whether R-fluoxetine is more effective or has fewer side effects than the parent drug, fluoxetine (Prozac). Ecopipam (SCH39166), a selective dopamine antagonist first used for treating cocaine abuse, is now being studied for treatment of binge eating. Ciliary neurotropic factor, which was originally developed for treatment of Lou Gehrig’s disease (amyotrophic lateral sclerosis, or ALS), is now being studied for the treatment of obesity.
Preliminary multicenter trials of leptin continue, she noted. Side effects at higher doses of leptin continue to be a problem, she said and added that weight loss is not universal. At the highest dosage, 0.3 mg/kg/day, patients have had significant weight loss, compared to placebo. Dr. Yanovski said there is a need to find a way to give smaller doses or find a way to manipulate the molecules so the product can be given orally (currently it is injected). One of the benefits of leptin is that lean body mass is not affected with weight loss. This is unique among all weight loss agents currently available, she said.
Dr. Yanovski told the audience, “The eventual goal is not to think about obesity as a single problem, but to define the type of obesity with psychological and blood tests, and to weigh the genetic influences. Then we can target specific behavioral or pharmacological interventions,” she said.