Do personality characteristics predict future alcohol problems after considering current demography, substance use, and alcohol response?

Background: Several personality traits predict future alcohol problems but also relate to demographic and substance-related variables that themselves correlate with later adverse alcohol outcomes. Few prospective studies have evaluated whether personality measures predict alcohol problems after considering current demographic and substance-related variables. Methods: Data from 414 drinkers without alcohol use disorder (AUD) from the Collaborative Study on the Genetics of Alcoholism (average age 20, 44% male) were followed over an average of 9 years. Time 1 (baseline) demography, AUD family history (FH), substance use and problems, and psychiatric histories were gathered using a standardized interview; the Level of Response (LR) to alcohol was measured by the Self-Report of the Effects of alcohol (SRE) questionnaire; and seven personality dimensions were extracted from the NEO Five-Factor Personality, Barratt, and Zuckerman scales. Analyses involved product–moment correlations of each baseline measure with the highest number of DSM-IV AUD criteria endorsed in any follow-up period, and hierarchical regression analyses evaluated whether the personality domains added significantly to the prediction of the outcome after adjusting for other baseline variables. Results: Significant correlations with the outcome were observed for baseline age, sex, length of follow-up, AUD family history, past cannabis use, and all alcohol-related baseline variables, including SRE-based LR, but not prior mood or anxiety disorders. All personality characteristics except extraversion also correlated with outcomes. A hierarchical regression analysis that included all relevant personality scores together demonstrated significant contributions to the prediction of future alcohol problems for demographics in Step 1; demographics and most baseline alcohol items, including response level, in Step 2; and cannabis use in Step 3; after which demographics, LR, baseline alcohol problems, cannabis use, and higher sensation seeking added significantly in Step 4. Regression for each personality domain separately revealed significant contributions to Step 4 for all personality domains except openness. Lower levels of response to alcohol added significantly to all regression analyses. Conclusions: Most tested personality scores and lower levels of response to alcohol contributed to predictions of later alcohol problems even after considering baseline demographic and substance use measures.