The high rate of comorbid substance abuse in women with bulimia nervosa (BN) has remained consistent in the literature. This article reviews the prevalence of substance abuse in BN and summarizes treatment approaches for persons with BN and comorbid substance abuse.
Prevalence
Studies conducted in community and clinical settings continue to demonstrate that the prevalence of substance use disorders is higher among women with BN than in women with other eating disorder diagnoses and in women in the general population.1-3 Dansky and colleagues2 reported on the prevalence of alcohol(Drug information on alcohol) use disorders and BN in a national sample of 3006 women; approximately 31% of the women with BN had a history of alcohol abuse. In comparison, 21.7% of women who did not have an eating disorder reported this history.
More recently, Blinder and associates1 examined the point prevalence of psychiatric comorbidity in 2436 female inpatients who had been admitted to an eating disorder program with varying primary eating disorder diagnoses. Significant differences between eating disorder diagnostic groups and comorbid substance use disorders were found during assessments performed at admission and discharge. In particular, inpatients with BN were twice as likely to have alcohol abuse/dependence (26%) than those with anorexia nervosa restricting subtype (3%), anorexia nervosa binge-purge subtype (14%), and eating disorder not otherwise specified (14%). Moreover, inpatients who had BN were 3 times more likely to have polysubstance abuse/dependence than women with anorexia nervosa restricting type (10% vs 2%, respectively).
These results are similar to those of an earlier study conducted in a clinical setting, in which 24% of women with BN and 17% of women with anorexia nervosa were found to have a DSM-III-R lifetime alcohol use disorder.3
The Table summarizes studies that have examined comorbid substance use/abuse/dependence and eating disorders.
Typical substances of abuse
Women with BN abuse an unusually wide range of substances. Substances commonly abused by this population include alcohol, street drugs (eg, cocaine and marijuana), prescribed medications, and non-psychoactive substances (eg, laxatives, emetics, diuretics, and diet pills). Young women with BN are at greatest risk for abusing substances and experimenting with many types of substances.
The literature concerning alcohol use disorders and BN has been quite consistent. Findings suggest that alcohol use disorders tend to co-occur more often in women with bulimic symptoms (eg, women with BN or anorexia nervosa binge-purge subtype) than in women with restricting symptoms (eg, those with anorexia nervosa restricting subtype).1,3
Similarly, rates of illicit drug use have generally been found to be higher in women with BN than in women with anorexia nervosa. Wiederman and Pryor4 found that more women with BN reported having used amphetamines (18%), barbiturates (10%), marijuana (24.7%), and cocaine (12.5%) than women with anorexia nervosa (3%, 2.2%, 5.2%, and 1.5%, respectively).
Women with BN may become physically and/or psychologically dependent on prescription medications, such as tranquilizers, benzodiazepines, and hypnotics, at therapeutic doses. Women with BN self-medicate and increase their doses of psychotropic drugs significantly more than women with anorexia nervosa restricting subtype.5 Moreover, the use of non-psychoactive substances, which initially may be used in an attempt to control or modify body weight or shape, later develops into an addictive pattern in most women with eating disorders.
The literature suggests that the association between BN and substance use disorder may be more specific. That is, substance use disorders may be associated with bulimic symptoms, such as bingeing or purging, rather than simply BN.
Causality of comorbid bulimia nervosa and substance abuse
Why do women with BN have such high rates of substance use and misuse? One possible explanation is that such women may have underlying impulsive personality traits. Such traits may be unique to a subset of so-called multi-impulsive bulimics. These women engage in other impulsive behaviors, such as gambling, shoplifting, promiscuity, and substance use, in addition to their impulsive eating disorder behaviors.6 The origin of such impulsivity is not known.
However, the observation of high rates of physical and sexual abuse in patients with BN may offer some clues.7 Higher rates of substance abuse are known to occur in individuals with posttraumatic stress disorder. Similarly, bulimic behaviors, such as bingeing and purging and alcohol and drug use, may be a means of regulating emotional disturbances. These emotional disturbances could be related to a history of childhood trauma.
Moreover, comorbid Axis I and II disorders, such as depression and borderline personality disorders, are frequently diagnosed in women with BN or substance use disorders. These additional diagnoses may moderate the association between BN and substance abuse. Again, the connection between the development of Axis II disorders and a history of trauma is not well understood and deserves further attention.
Finally, some research shows elevated rates of substance abuse in the families of individuals who have BN.8 The development of one or the other condition may act as a trigger that precipitates the onset of the second illness, despite each of them being inherited separately.
