The two most common eating disorders are bulimia nervosa and anorexia
nervosa. Both disorders, primarily affect young women, therefore the majority
of the research on eating disorders has been done with women subjects.
The onset of bulimia is between adolescence and early adulthood while the
onset of anorexia is between early and late adolescence. Not only is the
onset different but the disorders are unique. Bulimia nervosa is characterized
by loss of control over eating which leads to food binges. These episodes
are interspersed with episodes of purging, such as vomiting or laxative
abuse, to keep weight down. The goal of anorexia is also to keep weight
down , but to a more severe extent. Anorexia nervosa is marked by "a
relentless pursuit of thinness, intense fears of becoming fat, and a distorted
body image" (Lilenfeld 1996). There is a substantial weight loss and
amenorrhea. These changes occur by either restriction of food intake which
is labeled restrictive anorexia, or starvation with bouts of purging which
is labeled binge eating/purging anorexia.
The causes and issues underlying eating disorders still remain, for the most part, a mystery. For this reason much investigation has gone into any issues which may be related to eating disorders. The topic which will be analyzed in this paper is the comorbidity of eating disorders and drug/alcohol abuse. In a review of fifty-one studies by Lilenfeld and Kaye, rates of alcohol/drug abuse were found to differ significantly among restricting anorexics, binge eating/purging anorexics and bulimics. "Depending on the study analyzed, the rates of alcohol abuse or dependence among restricting anorexics ranged from zero to six percent and the rates of other drug abuse or dependence ranged from five to nineteen percent, In contrast, the corresponding rates in bulimics were significantly higher, ranging from fourteen to forty-nine percent for alcohol abuse or dependence and from eight to thirty-six percent for other drug abuse or dependence. Comparably high rates were found in binge eating/purging anorexics" (Lilenfeld 1996).
The figures are defined as high because in the general population the rate of alcohol abuse or dependence in women is twelve percent and ten percent for other drug abuse or dependence. The only area where drug or alcohol abuse does not appear to be related to eating is with anorexia nervosa. In this area alcohol abuse appears to be less than the general population.
In another compilation of studies by Schuckit, Tipp, Anthenelli, and Buchotz differing statistics were found as to whether there was increased alcohol abuse among women with bulimia. One group of studies regarding bulimia stated that between one fourth and one half of individuals with bulimia "drank one or several times per week" or "had evidence of a problem with street drugs". Another stated that between fourteen and over fifty percent of individuals met the criteria for alcohol dependence. Yet another study found only a twelve percent rate of severe alcohol problems among a group of women with bulimia. This evidence states that there is no proof for substance abuse increase in bulimia because the rate in the general population is twelve percent.
A study by Strober, Freeman, Bower, and Rigali, a ten year perspective,
non-substance abuse adolescents who had been hospitalized for treatment
of anorexia nervosa were observed to investigate the comorbidity of alcohol/drug
abuse and eating disorders. This study found that it is imperative to distinguish
between the two subgroups of anorexia nervosa: binge eating and restricting.
Binge eating was found to be the predictor of increased risk of substance
abuse in the ten year study. It was also found that subjects who began
binge eating earlier in life were more likely to be substance abusers than
those who began binge eating later in life.
Another method of finding comorbidity between eating disorders and substance
abuse is to research women whose primary diagnosed problem is alcoholism.
In one study of alcohol dependent inpatients, it was found that thirty
percent of these women had lifetime histories of eating disorders. One
third were diagnosed with anorexia nervosa and two thirds were diagnosed
with bulimia nervosa. In this study the eating disorder usually preceded
the alcohol use disorder (Lilen feld 1996). Other studies reported that
as many as one third of twenty alcoholic women had a "serious eating
disorder" usually involving the bulimic sub-type. Lastly thirty percent
or twenty-two out of seventy-three women in treatment for substance abuse
disorders showed evidence of eating-related problems" (Schuckit 1996).
Although it is proven that eating disorders and substance abuse frequently co-exist nobody understands exactly why. There are four potential explanations: "the two disorders have different causes, but the presence of one disorder may increase the person's chances of developing the other, An independent disorder causes the both disorders, The two disorders have some risk factors in common, whereas other risk factors are specific to each disorder and Both disorders are shared manifestations of a shared underlying etiology" (Lilenfeld 1996). This last hypothesis has been studied the most extensively. Supporters of this theory believe that eating disorders and substance and abuse disorders are manifestations of a predisposition toward impulsivity which relates to "a common mechanism involving endogenous opioids. Endogenous opioid compounds that occur naturally in the body and act like opiates have been shown to play a role in regulating alcohol consumption as well as appetite" (Lilenfeld 1996).
Varner states that support for this hypothesis are the many commonalties shared by the two disorders. "In both disorders it is common for patients to have a family history of drug and alcohol abuse, to experience cravings for particular foods or substances, and to be unable to control food or psychoactive substance intake. Other similarities include cognitive dysfunction, use of food or substances to relieve negative affect, secretiveness about the problem behavior, and social isolation. In addition, patients with eating or substance related disorders tend to maintain the problem behavior despite adverse consequences and deny the presence and severity of the disorder. They also frequently experience accompanying depression" (Varner 1995).
Although eating disorders and substance related disorders share commonalties, there are differences. An example is that tolerance may occur with substance abuse, but not with food intake. Another difference is in treatment. Abstinence is the key for substance abuse but does not work with eating disorders. Telling bulimic patients to eat only certain foods can lead to feelings of deprivation and lead to loss of control.
Studies have also been used to refute this hypothesis. In one, families of patients with eating disorders were compared with those of control families to check for incidence of substance abuse. The families were then further separated: eating disordered patients with substance abuse histories and eating disordere patients without. If the hypothesis was to be proven true then the families of those with bulimic substance abuse relatives and those with non- substance abuse relatives would have the same, prevalence of substance abuse. The results disproved the hypotheses. Increased substance abuse was found only in families of bulimic substance abuse patients.
Yet another study analyzed six psychiatric disorders in women, including
bulimia nervosa and alcoholism. One thousand thirty female twin pairs were
interviewed and evaluated. "Statistical analyses examining correlation's
of multiple variables between and across twin pairs indicated that bulimia
nervosa and alcoholism were best explained by two different genetic factors"
In the past treatment of dual diagnosis first centered on the substance abuse. Substance abuse was believed to be the more serious of the two. Today disordered eating and purging are believed to be " as psychologically and biologically damaging as substance abuse" (Varner 1995). Therefore the current trend is to treat the two simultaneously. When the two are not treated simultaneously the fear is that one problem will get worse while the other improves. Therapies which have proved to be affective in treating eating disorders are cognitive behavioral therapy, such as stimulus control and problem solving, and anti depressant therapy. "CBT focuses on identifying and restructuring distorted thoughts which in turn influence behavior" (Lilen feld 1996). Some examples of these thoughts are negative body image and fears of fatness. Also, more direct behavioral strategies are used such as imposing a time delay between a binge and vomiting. The hope is that eventually the time delay will increase.
Another aspect of dual diagnosis which must be attended to are health issues. These patients need thorough medical assessments and nutritional consultations. "Management of these patients should include monitoring their weight, food intake, and purging behavior as well as assessing their cardiac, fluid, and mineral status's" (Lilenfeld 1996). These patients also need to be educated about how to establish normal eating patterns. Issues such as meal planning and food shopping should be addressed. Another technique is learning about an exchange food based plan with a goal such as weight gain (Varner 1995).
When addressing treatment of dual diagnosis it is important to remember
that there is little empirical evidence on the treatment of dual diagnosis.
Therefore different and varied treatment programs are used in hopes of
improving this problem. In essence, treatment of dual diagnosis is still
a guessing game.
Lilenfeld, L. & Kaye, W. (1996). The Link Between Alcoholism and
Eating Disorders. Alcohol Health and Research World, 20, 94- .
Schuckit, M. , Tipp, J. , Anthenelli, R. & Bucholz. K. (1996). Anorexia
Nervosa and Bulimia Nervosa in Alcohol Dependent Men and Women and their
Relatives. The American Journal of Psychiatrity, 153, 75- .
Strober, M. , Freeman, R. ,Bower, S. ,& Rigali, J. (1996). Binge
Eating in Anorexia Nervosa Predicts Later Onset of Substance Use Disorder.
Journal of Youth and Adolescence, 25, 519- .
Varner, l. (1995). Dual diagnosis: Patients with Eating and Subatance Related Disorders. Journal of the American Dietic Association, 95, 224- .
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