A Prospective Assessment of Reports of Drinking to Self-medicate Mood Symptoms With the Incidence and Persistence of Alcohol Dependence

CONTEXT: Mood disorders and alcohol dependence frequently co-occur. Etiologic theories concerning the comorbidity often focus on drinking to self-medicate or cope with affective symptoms. However, there has been little to no prospective studies in population-based samples of alcohol self-medication of mood symptoms with the occurrence of alcohol dependence. Furthermore, it’s not known whether these associations are effected by treatment, or symptom severity. OBJECTIVE: Alcohol self-medication of mood symptoms is hypothesized to increase the probability of subsequent onset, and the persistence or chronicity of alcohol dependence. DESIGN: Prospective study, the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). SETTING: Nationally representative survey of the US population. PARTICIPANTS: Drinkers at risk for alcohol dependence among the 43,093 adults surveyed in 2001-2 (wave 1); 34,653 of which were re-interviewed in 2004-5 (wave 2). MAIN OUTCOME MEASURE: Association of alcohol self-medication of mood symptoms with incident and persistent DSM-IV alcohol dependence using logistic regression and the propensity score method of inverse probability of treatment weighting. RESULTS: The report of alcohol self-medication of mood symptoms was associated with an increased odds of incident alcohol dependence at follow-up (adjusted odds ratio [AOR]=3.10, 95% confidence interval [CI]=1.55-6.19, p=0.002), and persistence of dependence (AOR=3.45, CI=2.35-5.08, p<0.001). The population attributable fraction (PAF) was 11.9% (CI=6.7-16.9%) for incident dependence, and 30.6% (CI=24.8-36.0%) for persistent dependence. Stratified analyses were conducted by age, sex, raceethnicity, mood symptom severity, and treatment history for mood symptoms. CONCLUSIONS: Individuals who drink to alleviate mood symptoms are more likely to develop alcohol dependence and to have persistent dependence once it develops. These associations occur among individuals with sub-threshold mood symptoms, with DSM-IV affective disorders, and for those who have received treatment. Drinking to self-medicate mood symptoms may be a potential target for prevention and early intervention efforts aimed at reducing the occurrence of alcohol dependence.