Prior studies of the comorbid relationship of mood and alcohol conditions provide evidence that there is likely a bidirectional association. Some studies have found that alcohol dependence is the primary condition and is associated with increases in the risk of depression and other mood conditions;22;23 while others have found alcohol dependence to be secondary, whereby mood disorders are associated with an increased risk for the new development of alcohol use disorders.24 In most instances, depression has been found to be secondary to alcohol dependence.25 It is also plausible that there is a common etiology for both conditions that might include a genetic vulnerability, or environmental factors.26 Etiologic theories to account for mood disorder as the primary condition often focus on the potential use of alcohol as a method of self-medicating, or coping with affective symptoms.27 Although a frequently considered hypothesis, there is a paucity of research which has assessed this association. In particular, there is little data from prospective population-based studies, which reduce potential biases related to temporal association and sample selection. In an inpatient sample, Holahan and colleagues28 found
