Does a U-shaped relationship exist between alcohol use and DSM-III-R mood and anxiety disorders?

Background: In recent community surveys, abstainers and heavy drinkers of alcohol have reported more mood and anxiety symptoms than moderate drinkers (U-shaped relationship). The present study was aimed at extending this finding by investigating this potential U-shaped relationship using structured diagnostic interviews to assess mood and anxiety disorders. Methods: Data came from two contemporaneous surveys, the National Comorbidity Survey (NCS; N=6780) and the Mental Health Supplement of the Ontario Health Survey (OHS-MHS; N=7001). The University of Michigan Revision of the Composite International Diagnostic Interview (UM-CIDI) was used to make DSM-III-R psychiatric diagnoses in both surveys. Three mutually exclusive lifetime alcohol use categories were compared: (1) Alcohol abstainers—individuals reporting no alcohol use or less than 12 drinks in any year throughout their life. (2) Moderate drinkers—individuals that did not meet criteria for alcohol abstainers or problem drinkers. (3) Problem drinkers—DSM-III-R lifetime alcohol abuse, dependence or hazardous levels of alcohol use. Results: After controlling for demographic variables, alcohol abstainers were not found to have significantly higher rates of mood and anxiety disorders in comparison with moderate drinkers. However, problem drinking was significantly associated with mood and anxiety disorders. Conclusions: Across both surveys, there was no evidence of a U-shaped relationship between lifetime alcohol consumption and lifetime mood and anxiety disorders.