Alcohol Consumption Questionnaire: Scale development in a sample of Mexican American young adults and association with ADH7.

BACKGROUND: To understand why some individuals who develop alcohol use disorders (AUD) first begin to drink heavily, a number of scales have been developed that index aspects of alcohol craving and restraint from drinking. We developed a new measure called the Alcohol Consumption Questionnaire (ACQ), based in part on items modified from scales used to index binge eating because there are data to suggest that binge eating and binge drinking may share common antecedents. We present an initial validity study using data from a sample of Mexican Americans.

METHODS: Data were from 699 Mexican American young adults in San Diego County, CA. A subsample (n=60) had short-term test-retest data. Factor analysis and reliability assessment guided item reduction. Item response theory (IRT) analyses quantified item severity and identified questions with differential item functioning (DIF). Logistic regression assessed associations of mean scale scores with AUD, adjusting for key demographics, alcohol expectancies and subjective response to alcohol. We also examined associations with a protective genetic variant downstream from the alcohol dehydrogenase 7 gene (ADH7).

RESULTS: The scale was reduced from 20 to 14 questions, which can be summarized by a single overall score (Cronbach's alpha=0.896) or by two sub-scores (Consumption: 12 items, Cronbach's alpha=0.896; Enjoyment: 2 items, Cronbach's alpha=0.780). Test-retest reliability was very high (0.80-0.98) in this sample. The overall ACQ score and each subdomain score were strongly associated with AUD (ORs= 5.95 mild; 11.41 moderate; 48.56 severe) and family history of AUD. Respondents with the protective genetic variant had significantly lower overall ACQ scores (p<.001).

CONCLUSION: The ACQ is a novel measure of alcohol consumption with strong relationships with both the AUD phenotype and ADH7 gene variants in a sample of Mexican American young adults.