Alcohol abuse or dependency has been reported to occur frequently in patients with eating disorders and in their family members. Such studies, as well as phenomenology, biological studies, and treatment strategies suggest a link between alcohol abuse/dependency and bulimia nervosa, in particular. Few of the family studies to date, however, have used state- of-the-art family study methodologies used to investigate genetic epidemiology in other psychiatric illnesses. These methods include face- to-face interviews of first-degree relatives using structured diagnostic interview schedules with diagnosis being made blind to the identity of the probands. This three year study, which will use these state-of-the-art family methodologies, has 5 aims.
Aim 1 will determine the lifetime prevalence of alcohol dependence or abuse (PSUD) in 49 female probands with bulimia nervosa (BN) and 49 female probands with anorexia nervosa (AN) compared to 49 matched normal female controls (NC).
Aim 2 will determine the lifetime prevalence of PSUD in the first- and second-degree relatives of the eating disorder probands compared to the probands of matched normal controls (NC). We hypothesize that BN probands and their families will have a significantly greater lifetime prevalence of PSUD than will AN or NC or their families. It is not known why BN probands and their families have an elevated prevalence of PSUD.
Aim 3, the major aim of this study, will test several hypotheses about the mechanisms of association between PSUD and BN. We will segregate BN probands by the presence or absence of PSUD. Analysis of the prevalence of PSUD and BN in their relatives will be used to determine whether BN and PSUD are expressions of a common transmissible factor or are separate, but co-existing disorders. Considerable evidence suggests that BN generally occurs in women and alcoholism in men. We will determine whether there is a sex-specificity to the occurrence of eating disorders and PSUD in the relatives of probands with eating disorders. Taken together, we seek to test the hypothesize that BN and PSUD have a common familial transmission which expresses itself as BN in females and alcoholism in males. This study will have 2 final aims.
Aim 4 is to determine the relationship of the familial aggregation of several other psychiatric disorders, particularly depression and anxiety, to PSUD and eating disorders.
Aim 5 is to determine whether sub-typing of eating disorder patients into AN and BN has specificity in terms of familial transmission of these sub-types of eating disorders. That is, do these disorders """"""""breed true."""""""" In summary, this study will provide a better understanding of the mechanisms responsible for the high prevalence of alcohol and substance abuse in the eating disorders, particularly BN.