Objective: To compare illness characteristics, comorbidities, treatment utilization, and family history among individuals with comorbid bipolar I disorder and alcohol use disorders (AUD) based on temporal priority of onset.
Method: The 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions identified respondents with lifetime comorbid bipolar I disorder and AUD for whom AUD were antecedent (Alcohol First; N = 311), the onset of the 2 conditions occurred in the same year (Same Year; N = 113), or bipolar I disorder was antecedent (Bipolar First; N = 233). Diagnoses were generated using the National Institute on Alcohol Abuse and Alcoholism Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV Version. This study examined between-group differences in bipolar I- and AUD-related variables.
Results: Bipolar First respondents were most likely to experience prolonged manic episodes. There were no differences in the 12-month prevalence of bipolar I disorder among respondents with prior history of bipolar I disorder. The 12-month prevalence of AUD among respondents with prior history of AUD was lower among Alcohol First respondents compared to Same Year or Bipolar First respondents. Same Year respondents were most likely to seek AUD treatment and reported comparatively short latency between onset and treatment of both bipolar I disorder and AUD. The prevalence of family history of comorbid depression and AUD was greatest among Same Year respondents. Same Year respondents also showed the lowest prevalence of anxiety disorders. Overall psychosocial functioning was similar across groups.
Conclusion: Temporal priority in comorbid bipolar I disorder and AUD is associated with several significant between-group differences in features of bipolar I disorder and AUD severity, treatment utilization, other comorbidities, and family history. Same-year onset of bipolar I disorder and AUD may be a marker of a specific subtype of bipolar I-AUD comorbidity. Potential implications of these findings are discussed.