A long-term, large-scale study has found that an Internet-based intervention program may prevent some high risk, college-age women from developing an eating disorder. The study, funded by the National Institutes of Health's (NIH) National Institute of Mental Health (NIMH), was published in the August 2006 issue of the Archives of General Psychiatry.
The researchers conducted a randomized, controlled trial of 480 college-age women in the San Francisco Bay area and San Diego, Calif., who were identified in preliminary interviews as being at risk for developing an eating disorder. The trial included an eight-week, Internet-based, cognitive-behavioral intervention program called "Student Bodies," which had been shown to be effective in previous small-scale short-term studies. The intervention aimed to reduce the participants' concerns about body weight and shape, enhance body image, promote healthy eating and weight maintenance, and increase knowledge about the risks associated with eating disorders.
The online program included reading and other assignments such as keeping an online body-image journal. Participants also took part in an online discussion group, moderated by clinical psychologists. Participants were interviewed immediately following the end of the online program, and annually for up to three years thereafter to determine their attitudes toward their weight and shape, and measure the onset of any eating disorders.
"Eating disorders are complex and particularly difficult to treat. In fact, they have one of the highest mortality rates among all mental disorders," said NIMH Director Thomas Insel, M.D. "This study shows that innovative intervention can work, and offers hope to those trying to overcome these illnesses."
Over the course of a lifetime, about 0.5 to 3.7 percent of girls and women will develop anorexia nervosa, and about 1.1 to 4.2 percent will develop bulimia nervosa. About 0.5 percent of those with anorexia die each year as a result of their illness, making it one of the top psychiatric illnesses that lead to death.
Anorexia generally is characterized by a resistance to maintaining a healthy body weight, an intense fear of gaining weight, and other extreme behaviors that result in severe weight loss. People with anorexia see themselves as overweight even when they are dangerously thin. Bulimia generally is characterized by recurrent episodes of binge eating, followed by self-induced purging behaviors. People with bulimia often have normal weights, but like those with anorexia, they are intensely dissatisfied with their bodies. All eating disorders involve multiple biological, behavioral and social factors that are not well understood.
The intervention appeared to be most successful among overweight women who had elevated body mass indexes (BMIs) of 25 or more at the start of the program. In fact, among these women in the intervention group, none developed an eating disorder after two years, while 11.9 percent of the women with comparable baseline BMIs in the control group did develop an eating disorder during the same time frame. BMI is a reliable indicator of a person's body fat by measuring his or her weight and height.
The program also appeared to help women in the San Francisco Bay area who had some symptoms of an eating disorder at the start of the program, such as self-induced vomiting; laxative, diet pill or diuretic use; or excessive exercise. Of those in the intervention group with these characteristics, 14 percent developed an eating disorder within two years, while 30 percent of those with these characteristics in the control group developed an eating disorder during the same time frame.
The authors suggest that the intervention helped these high-risk women become less concerned about their weight and shape, while also helping them understand healthier eating and nutrition practices.
"This is the first study to show that eating disorders can be prevented among high-risk groups," said lead author C. Barr Taylor, M.D., of Stanford University. "The study also provides evidence that elevated weight and shape concerns are causal risk factors for developing an eating disorder," he added.
The study suggests that relatively inexpensive options such as Internet-based interventions can have lasting effects on women at high risk of developing an eating disorder. However, the authors note that the results cannot be generalized widely because there were differences in the women's baseline characteristics and treatment responses between the two sites used in the study.
Also, the rate at which the women stuck with the program was very high--nearly 80 percent of the online program's Web pages were read--suggesting that the participants were unusually motivated. "Women who are less motivated may be less likely to participate in or stick with this type of long-term intervention," added Taylor.
In addition, women with restricted or no access to computers would not be able to benefit from an online intervention program. However, the authors conclude that such Internet-based programs may be a good first step in a diligent program designed to screen women for potential eating disorder risks.
Additional study authors are Susan Bryson, MS, MA of Stanford University; Kristine H. Luce, PhD of Stanford University; Darby Cunning, MA of Stanford University; Angela Celio, PhD of the University of Chicago; Liana B. Abascal, MA of San Diego State University; Roxanne Rockwell of San Diego State University; Pavarti Dev, PhD of Stanford University; Andrew J. Winzelberg, PhD of Stanford University; and Denise E. Wilfley, PhD of Washington University Medical Center.
The National Institute of Mental Health (NIMH) mission is to reduce the burden of mental and behavioral disorders through research on mind, brain, and behavior. More information is available at the NIMH website, http://www.
The National Institutes of Health (NIH) - The Nation's Medical Research Agency - includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.