Q. A sizeable percentage of my patients with anorexia nervosa (AN) also turn out to have problems with alcohol. I’ve wondered about the “chicken and egg” problem. Are there any meaningful connections between which one comes first and patterns bearing on treatment or prognosis? (RS, Philadelphia)

A. The fact is, a high percentage of patients with AN do seem to have alcohol use disorders (abuse/dependence) with varying degrees of severity. In one of the largest studies of its kind, in which 873 women with lifetime histories of AN were screened, Jessica Baker and her colleagues found that 161 had histories of alcohol use disorders. Of these 161, 71.4% reported that the AN came first; 21.7 % reported that the alcohol problems started first; and 6.8% reported that they started more or less simultaneously. Compared to AN patients without alcohol use disorders, those with comorbid alcohol problems were more likely to be of the binge-purge type and were more impulsive. However, the investigators found no reliable differences in overall symptom or personality patterns between those whose AN started first compared to those whose alcohol problems appeared first (Addictive Behaviors. 2012; 38: 1704 ). Whether other differences exist between these groups, for example regarding family histories, details of their alcohol disorder symptoms, or responses to various treatments will require further research.

— JY