The frequent comorbidity of substance abuse with bipolar disorder has long been known (1,2,3). Data from the National Epidemiological Survey on Alcohol-Related Conditions (NESARC) show that bipolar disorder has the strongest association with alcohol use disorders (AUDs) of any mood or anxiety disorder (2). Both clinical and community populations show that alcohol is the most commonly abused medication for both bipolar I and bipolar II disorders (2,3). Bipolar I patients with current alcohol use have been differentiated from patients with other bipolar disorders in that they show increased numbers of manic symptoms, increased impulsivity and increased high-risk of violent behavior (4,5). Hypomania and bipolar II disorder also put a patient at high risk for alcohol abuse and dependence. A 20-year longitudinal study comparing over 600 subjects with bipolar II disorder to those who did not develop mood disorders, revealed that those with bipolar II disorder had a 4.6-fold increased likelihood of developing alcohol abuse and a 2.2-fold increased likelihood to become alcohol dependent.

Not only is the co-occurrence of AUDs and bipolar disorders very common, but the use of alcohol also worsens the prognosis for bipolar disorder on virtually all parameters, as shown in Table 13.1.

Interestingly, although in the general population the risk of alcohol use and abuse is higher for men, Frye, Altshuler et al. showed that in patients with bipolar disorder, the risk of alcoholism was greater for women (odds ratio = 7.35) than for men (odds ratio = 2.77) (6). Women are also physically more vulnerable to the effects of alcohol than men. Women who abuse alcohol show increased liver and brain damage, increased negative effects
on cognition, increased rates of hepatitis C, human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), and breast cancer, as compared to those who do not abuse alcohol and as compared to men. Women with comorbid bipolar disorder and alcoholism are more prone to victimization, violence, and sexual abuse. These comorbid women also have nine times the rate of polysubstance abuse, three times the rate of social anxiety disorder, and four times the rate of depressive episodes as compared to women with bipolar disorder without alcoholism. They are also less likely to receive treatment for alcoholism than men with bipolar disorder (4,6).