RxPG News : Bulimia

Synthetic amylin curbs tendency to binge eat

Fri, 08 Jun 2007 15:59:37 PST

( from http://www.rxpgnews.com ) The synthetic form of a hormone previously found to produce a feeling of fullness when eating and reduce body weight, also may help curb binge eating and the desire to eat high-fat foods and sweets. The findings on fast food consumption and binge eating tendencies are based on a 6-week research study of 88 obese individuals.

"Satiety hormones are commonly thought to control food intake by signaling to the brain when we are full," said Christian Weyer, M.D., the study's senior author and executive director of clinical research at Amylin Pharmaceuticals, Inc., in San Diego, Calif. "The findings of our clinical study further suggest that satiety hormones such as amylin can exert multiple effects on human eating behavior, such as reduced intake of highly-palatable foods and reduced binge eating tendency."

The study was carried out in 10 U.S. research sites and was reported by Steven R. Smith of the Pennington Biomedical Research Center in Baton Rouge, La.; John E. Blundell of the University of Leeds, United Kingdom; and Colleen Burns, Cinzia Ellero, Brock E. Schroeder, Nicole C. Kesty, Kim Chen, Amy E. Halseth, Cameron W. Lush and Christian Weyer, all of Amylin Pharmaceuticals.

Higher Incidence of Bulimia compared to Anorexia in Urbanised areas

Fri, 01 Dec 2006 15:04:15 PST

( from http://www.rxpgnews.com ) Urban life is a potential environmental risk factor for bulimia nervosa, but not for anorexia nervosa, according to a short report from The Netherlands in the December issue of the British Journal of Psychiatry.

The association between degree of urbanisation and a number of mental disorders is well established. Schizophrenia, psychosis and depression are known to occur more frequently in towns and cities.

In 1995 it was first reported that bulimia nervosa is associated with urban life. This study extends the research by adding data collected a decade later.

A network of about 63 general practitioners coordinated by the Netherlands Institute for Health Services Research recorded the number of newly diagnosed cases of anorexia and bulimia nervosa in their practices between 1985–1989 and 1995–1999.

The study population was divided into three levels of urbanisation: rural (20% or more of population engaged in agricultural labour), large cities (more than 100,000 inhabitants), and urbanised areas (all other areas).

During the 2 periods a total of 113 patients with anorexia (107 females and 6 males) and 110 with bulimia nervosa 107 females and 3 males) were newly diagnosed. Because there were so few male patients, the researchers analysed data from female patients only.

The incidence rate per year per 100,000 women-years for anorexia was 17.4 in rural areas, 20.2 in urbanised areas and 11.5 in large cities. Bulimia showed an incidence rate of 7.0 in rural areas, 16.7 in urbanised areas and 25.5 in large cities.

The main finding of the study was the association of bulimia incidence with degree of urbanisation in a ‘dose-response’ fashion. The incidence of bulimia was almost 2.5 times higher in urbanised areas than in rural areas, and 5 times higher in large cities than in rural areas. This is in contrast to the incidence of anorexia, which showed no association.

Anorexia and bulimia are thought to be closely related disorders e.g. core features of both are disturbed eating behaviours, and patients tend to move between diagnoses for the 2 disorders.

However, living in a large city seems to be strongly associated with the development of bulimia, but not with anorexia. The dose-response relationship of urbanisation and bulimia suggests causation.

Bulimia was relatively rare before 1970, but there was a sudden sharp rise in its incidence after 1980. Such fluctuations cannot be caused by changing genetic factors, as the time scale is too limited, suggesting a strong environmental influence.

The researchers explain the findings by 2 main hypotheses:

1. Migration. Adolescents tend to migrate to urban areas, where Dutch education facilities are usually located. These adolescents might already have developed bulimic symptoms but are ‘detected’ in the study in the more urbanised areas at an older age. The development of bulimia would then be independent of living in a large city. However, the researchers took account of age differences in their analyses, and the link with urbanisation remained.

2. Opportunity. In this hypothesis the higher incidence of bulimia in large cities is explained by the ability to obtain large amounts of food inconspicuously. In addition, the relative anonymity in large cities makes it easier to engage in secretive behaviour.

Other intra- and inter-personal factors may possibly account for the findings, and factors such as social cohesion, interpersonal trust and informal social control may also be involved, as they affect mental health.

In further studies, the residential history of participants should be taken into account, along with the time of onset of the bulimic symptoms.

Investigating the psychology of food consumption

Thu, 22 Jun 2006 16:57:37 PST

( from http://www.rxpgnews.com ) An article published in the recent issue of Psychological Science investigates the psychology of consumption. The study's findings demonstrate that individuals have a strong tendency to eat only a single unit of food, regardless of the unit's size or caloric value.

The authors conducted experiments with offering free food in public areas, varying the size of the product unit and the size of the serving utensil. In one experiment, researchers observed a mixing bowl of M&M's in the lobby of an apartment building, setting the serving spoon size at variance. The results demonstrate an identifiable unit bias, as passersby tended to take a single unit or spoonful of food without consideration for its size or quantity. As tests were conducted both within eyesight of others and in a more discreet location, the bias in favor of consuming a single unit cannot be attributed solely to the avoidance of perceptible gluttony.

"It is more than just people being afraid of appearing greedy," state the authors. "We have a culturally enforced 'consumption norm,' which promotes both the tendency to complete eating a unit and the idea that a single unit is the proper amount to eat." The concept of unit bias helps explain how environmental differences in portions and package sizes impact overall consumption and may provide a foundation for a better understanding of the psychology of obesity.

Eating and Body Weight Regulated by Specific Neurons

Wed, 14 Sep 2005 03:18:38 PST

( from http://www.rxpgnews.com ) Researchers at Yale School of Medicine provide direct evidence that two parts of a neuronal system, one that promotes eating and another that suppresses eating, are critical for the acute regulation of eating and body weight, according to a study published online in the September 11 issue of Nature Neuroscience.

The paper makes it clear that the agouti-related peptide-expressing (AgRP) neurons are mandatory for eating. Previous studies showed that the brain, particularly the hypothalamus, is responsible for the regulation of eating, said co-senior author Tamas Horvath, chair and associate professor in the Section of Comparative Medicine, and associate professor in neurobiology and the Department of Obstetrics, Gynecology & Reproductive Sciences. But until now, no experimental evidence was available to prove that AgRP neurons are critical for acute regulation of eating.

Horvaths collaborator Jens Bruening of the University of Cologne in Germany introduced the avian diphtheria toxin receptor into neurons in the feeding support system of transgenic mice. When the animals were adults, two injections of toxin caused the specific cell population to die within 48 hours, impairing the mouses ability to eat and resulting in acute anorexia. These mice also showed marked reduction in blood glucose, plasma insulin and Leptin concentrations.

Our results confirm the hypothesis that these two systems are critical for eating and the cessation of eating, said Horvath. Previous transgenic approaches failed to provide this proof because of compensatory mechanisms that could operate during development. None of those actually knocked out neuronal function. In this case, however, neurons are gone and there is no time to replace their function.

In explaining the significance of the finding, Horvath said, It is important to ensure that the multibillion dollar academic and pharmaceutical approach against metabolic disorders is leaning in the right direction. The approach in general could also eventually lead to specific destruction of cells in other kinds of diseases.

Childhood sexual abuse linked to eating disorders during pregnancy

Fri, 02 Sep 2005 02:20:38 PST

( from http://www.rxpgnews.com ) Pregnant women with a history of eating disorder symptoms are more likely to have a history of unwanted sexual experiences, according to a study published in the September issue of the British Journal of Psychiatry.

Women with marked concern during pregnancy about their weight or shape, or who report using laxatives or self-induced vomiting to control their weight, are also more likely to have a history of sexual abuse.

Although some research indicates that childhood sexual abuse may lead to eating disorders, this evidence does not come from large-scale population studies. This study was designed to explore which early experiences, recalled during pregnancy, were associated with both lifetime, and antenatal, eating disorder symptoms in a community sample.

The Avon Longitudinal Study of Parents and Children, also known as 'Children of the Nineties' project, recruited all women living in the three health districts in Avon who had an expected delivery date between 1st April 1991 and 31st December 1992. Information was collected at recruitment from 14,069 women, but only those who responded to all prenatal questionnaires were included in this study.

The women completed three postal questionnaires: Having a Baby, sent at 18 weeks' into pregnancy; Your Pregnancy, sent at 32 weeks; and About Yourself, which could be completed at any time during the pregnancy.

Your Pregnancy included one question about childhood sexual abuse, and a detailed section of questions about sexual experiences before the age of 16. The same questionnaire also included questions covering eating and weight concerns in the previous 28 days, and before pregnancy.

It was found that mental health problems of the women's own parents, physical and emotional cruelty, sexual abuse and recall of an unhappy childhood all predicted lifetime eating problems, laxative use and vomiting during pregnancy, as well as marked concern during pregnancy over body shape and weight.

Early sexual abuse was a significant independent predictor of lifetime eating disorder and concern about shape and weight. It was noteworthy that a low level of social support was also a significant predictor of weight and shape concerns during pregnancy.

The researchers comment that the multifactorial influences on the development of eating disorder symptoms are substantiated by this large-scale community study.

There are public health implications for these results. Maternal eating problems in the postnatal period have been shown to pose a particular risk to the developing child by interfering with parenting and child growth. Women with excessive concerns about shape and weight are less likely to plan breast-feeding.

Health professionals dealing with pregnant women need to be aware of the prevalence of eating disorder symptoms and the possible association - in some women - with a history of adverse experiences in childhood.

Further research is needed to explore these associations. Interventions designed to improve the outcome for mothers and their children by addressing women's eating disorder symptoms will need to be tested.

Overactive dopamine receptors may help explain eating disorder's symptoms

Fri, 08 Jul 2005 00:35:38 PST

( from http://www.rxpgnews.com ) Just why those with anorexia nervosa are driven to be excessively thin and seem unaware of the seriousness of their condition could be due to over-activity of a chemical system found in a region deep inside the brain, a University of Pittsburgh study suggests. Reporting in the journal Biological Psychiatry, researchers found an over-activity of dopamine receptors in the brain's basal ganglia, an area known to play a role in how people learn from experience and make choices.

Results of the study, led by Walter Kaye, M.D., of the University of Pittsburgh School of Medicine, and Guido Frank, M.D., now of the University of California at San Diego, contribute to the understanding of what may cause anorexia. The disorder affects about 1 percent of American women, some of whom die from complications of the disease. The research may point to a molecular target for development of more effective treatments than those currently available.

The study is the first to use positron emission tomography (PET) imaging to assess the activity of brain dopamine receptors, a neurotransmitter system that is best known for its role in controlling movement. These receptors also are associated with weight and feeding behaviors and responses to reinforcement and reward. Researchers used a harmless molecule designed to bind to the dopamine D2 and D3 receptors that lie on the membrane surface of neurons. Ten women who had recovered from anorexia nervosa for more than a year were studied, as were 12 normal female subjects. Because malnourishment affects brain chemistry, the researchers did not include acutely ill women in their study.

Since other studies have found reduced binding of these dopamine receptors in both people who are obese and those who have substance use problems, Drs. Kaye and Frank hypothesized that they would find just the opposite in women with anorexia.

Indeed, there was increased receptor binding in the basal ganglia's antero-ventral striatum in the women with a history of anorexia nervosa irrespective of their age, body mass index or time since recovery, but not in any of the healthy women. The antero-ventral striatum is an area known to modulate reward and reinforcement and is therefore important in learning from experience.

The researchers also found increased dopamine D2/D3 receptor activity in another part of the basal ganglia called the dorsal caudate, which is related to responses to and avoidance of harm. Such activity may help explain why women with anorexia exhibit exaggerated worry and concern about what might happen in the future.

"When they are ill, people with anorexia nervosa don't seek or respond to the kinds of comforts and pleasures most of us enjoy, including food. They also resist and ignore feedback that signifies their precarious state of health. They don't see an emaciated figure in the mirror, they ignore the most obvious warning signs and dismiss comments from loved ones that suggest they are seriously and medically ill. People with anorexia nervosa have extreme self-denial, not only of food, but often of many comforts and pleasures in life. Yet people with anorexia nervosa can be very energetic and productive," said Dr. Kaye, professor of psychiatry.

"Taken together, the alterations in the dopamine system may help explain the tell-tale symptoms of anorexia," added Dr. Kaye.

Alteration in dopamine function may affect the value of perceived rewards, or perhaps make it difficult to associate good feelings with things most people find rewarding, Dr. Kaye explained. Consequently, people with anorexia nervosa may appear to be obsessive about certain stimuli that may be uniquely rewarding to them, but may not be able to respond well to stimuli related to food or pleasure.

"This finding may help us better understand brain dopamine function across a whole spectrum of disorders, with respect to its contribution to the avoidance of food and other stimuli in anorexia nervosa on one end, and the desire for stimuli, such as in food and drug use on the other," added Dr. Frank, a fellow in child psychiatry.

More research is needed to address the many questions that remain, including what causes the dopamine receptors to be overactive in the first place. Genetic studies could yield some answers. Indeed, a study supported by the Price Foundation, which was recently published in the online edition of Neuropsychopharmacology, found alterations in genes for the D2 receptor in some individuals with anorexia nervosa. Dr. Kaye is a co-author of that paper and principal investigator of the Price Foundation studies, including a new multi-center study that is now recruiting families with two or more members who have or had anorexia nervosa to help identify the genes that contribute to the eating disorder.

Computerised CBT Treatment for Eating Disorder Patients to be Offered Online

Mon, 21 Mar 2005 18:56:38 PST

( from http://www.rxpgnews.com ) A new interactive multi-media self-help package for people diagnosed with eating disorders developed by a medical researcher at the University of Glasgow is now set to be delivered over the internet to adolescent sufferers.

The package, initially developed as a CD-ROM cognitive-behavioural self-help tool for the treatment of the eating disorder bulimia nervosa (BN), is set to revolutionise therapy. Bulimia nervosa is a common and disabling condition with significant personal, social and relationship costs.

University of Glasgow psychiatrist Dr Chris Williams and colleagues from the Institute of Psychiatry, London have now been awarded £191,000 from the Medical Research Council to launch an on-line version of the innovation, which is to be delivered to adolescents and young adults (aged 13 to 20) affected by bulimia nervosa.

Initial trials of the first stand-alone computerised treatment for eating disorder patients have been very successful and all patients involved in the pilot made significant improvements. The CD-ROM proved to be particularly effective in reducing vomiting and laxative abuse. This is important, as research has revealed that an early reduction in vomiting is a good predictor of positive longer-term outcomes in the treatment of bulimia.

Many patients with bulimia nervosa find it hard to access evidence based treatment such as cognitive-behavioural therapy (CBT). Although it is one of the preferred treatments for emotional and behavioural problems, CBT is labour intensive, and often not readily available.

Eating disorders are an increasing problem is Scotland, with about 10% of young women affected by such conditions. Given the rise in the number of sufferers and the under-provision of eating disorder services, a major challenge is to make treatment more accessible. Now, computer-based packages such as this are helping to bridge the treatment gap.

The shame and secretiveness surrounding bulimia makes computer-based treatment particularly appealing to sufferers. Other key advantages of the interactive intervention are that it allows an individually tailored delivery, it uses a variety of media, and a mixture of teaching styles to facilitate the learning of self-management.

A recent study into the usefulness of the CD-ROM involving 47 sufferers of bulimia revealed significant reductions in binging and self-induced vomiting. The pilot programme, run by the Eating Disorders Unit at South London and Maudsley NHS Trust lasted for 8 weeks and provided the treatment without any therapist input.

Modules include sessions on why people develop eating disorders, how to fight craving for food and how to break the vicious circle of Bulimia. Each session takes about 45 minutes at the computer and is backed up by additional support to put the learning into practice.

Dr Chris Williams from the University of Glasgow said: 'Eating disorders becoming very widespread in society. Not enough people are able to get treatment, but computer based approaches can offer people new ways to access much needed help. The CD-ROM and internet packages aim to provide another treatment option for people -and our experience to date is that this can be as effective as seeing a specialist practitioner. Many people feel really ashamed of the symptoms of bulimia such as bingeing and vomiting or purging of food. Some may actually prefer to use a CD-ROM rather than see a practitioner as a result. The computer-guided self-help treatment program for Bulimia has real potential to be utilised in routine clinical practice - especially as a first step to care.'

Only three short sessions of 20 minutes of clinician time is required to introduce the use of the CD-ROM, compared with a typical individual treatment time of 12 hours. The intervention has considerable potential for use in primary care and other settings as a first step in BN treatment.

Rates of bulimia nervosa increased threefold

Thu, 10 Feb 2005 17:54:38 PST

( from http://www.rxpgnews.com ) During the years 1988-1993 the incidence of anorexia nervosa detected in primary care remained stable, but rates of bulimia nervosa increased threefold. Since then, they have been falling. This study, published in the February 2005 issue of the British Journal of Psychiatry, set out to determine whether the incidence of anorexia remained stable, and that of bulimia nervosa continued to increase, in the years 1994-2000.

The General Practice Research Database was screened for new cases of anorexia and bulimia nervosa for those years. Annual incidence rates were calculated for females aged 10-39, and compared with rates for the previous five years.

It was found that annual incidence rates of anorexia nervosa remained remarkably stable over the period studied. Overall there was an increase in the incidence of bulimia, but rates declined after a peak in 1996.

The incidence rate for anorexia varied dramatically according to the age-gender group. In 2000 the incidence of anorexia diagnosed in primary care was 4.7 per 100,000 population. The relative risk for females to males was 12:1; and the highest incidence, 34.6 per 100,000, was found in females aged 10-19.

The results for bulimia were very different. The early 1990s showed a marked increase in women aged 10-39, which continued until 1996. Although there was an overall increase in reported cases of bulimia from 1988-2000, the incidence rate has fallen by 38.9% since this peak.

The relative risk of bulimia for females to males was about 18:1. The highest incidence, 35.8 per 100,000, was in females aged 10-19.

The authors of the study comment that there are several possible explanations for the peak in incidence of bulimia seen in the 1990s and its subsequent decline. Patients may now seek help from sources other than general practice. During the period studied, the UK-based Eating Disorders Association has experienced a dramatic increase in demand for its web-based messaging and e-mail service.

Another possible explanation relates to changes in professional or public attention to eating disorder symptoms. The earlier period of rising incidence might have been the result of increased recognition and detection efforts given to a new and 'fashionable'; diagnosis.

Intense press coverage of bulimia during the 1990s might also have contributed to the apparent rise in incidence. For example, the first reports of Princess Diana';s battle with bulimia appeared in Andrew Morton';s 1992 book, and subsequent media interest might have focused attention on bulimic symptoms and improved public awareness of the disorder.

It is notable that the Princess';s death in 1997 coincided with the beginning of the decline in bulimia incidence.

The authors of the study suggest that special detection and treatment efforts should be aimed at young women aged 10-19, as this is the group with the highest risk of both anorexia and bulimia nervosa.

General practitioners need more information about the presentation of eating disorder symptoms and the treatments available, to allow early and effective intervention.

Eating too much in childhood predicts development of bulimia nervosa in adulthood

Thu, 23 Sep 2004 22:43:38 PST

( from http://www.rxpgnews.com ) A new study has found that being overweight and eating too much in childhood was predictive of developing Bulimia Nervosa (BN) in adult life.

But childhood feeding problems did not predict later Anorexia Nervosa (AN).

This study was the first to compare sister pairs where one sibling developed an eating disorder and the other did not to investigate early feeding experiences as risk factors.

154 sister pairs were compared. Mothers were sent questionnaires to report on their daughters' childhood feeding experiences. Lifetime diagnosis of eating disorder was obtained with a semi-structured interview.

It was found that their having been overweight during childhood significantly predicted a diagnosis of BN, as did eating too much during childhood.

However, gastrointestinal problems, eating non-food items, such as wallpaper (known as 'pica'), not eating enough, unpleasant meals between the ages of one and ten and selective eating during the first year of life did not predict a diagnosis of eating disorder.

'Picky eating' was significantly protective for BN, but did not predict AN.

This study showed that sister pairs where one developed AN did not differ in maternal reports of eating habits during childhood, whereas siblings with BN in adulthood were significantly more overweight, less picky and ate more as children, compared with their healthy siblings.

The authors of the study suggest that a 'disinhibited' eating style could be an individual risk factor (i.e. not shared between sisters) for BN. This hypothesis needs to be tested with further research, but could have important implications for the prevention of eating disorders.