According to the ECA study, bipolar spectrum disorders were the Axis I disorders most likely to co-occur with an SUD, with 56% of any bipolar diagnosis being associated with a lifetime SUD (Regier et al. 1990). The rate was the highest for bipolar I disorder at 61%, versus bipolar II disorder at 48%; among the patients with bipolar I disorder, 46% had a lifetime rate of an AUD and 41% had a lifetime history of a DUD. Furthermore, according to the NCS, the odds ratios of 12-month AUDs and DUDS in patients with bipolar disorder were 6.3 and 8.2, respectively, and the odds ratios of having a lifetime AUD and DUD were 9.7 and 8.4, respectively (Kessler et al. 1996).