Test of a Clinical Model of Drinking and Suicidal Risk

Background: There are few data on the role of drinking patterns in suicidal thoughts or behavior among alcohol-dependent individuals (ADIs) and meager data on variables that may influence the role of drinking in suicidal thoughts and behavior. This study tested a heuristic model that predicts that drinking promotes suicidal thoughts and behavior, the association is mediated (accounted for) by depressive symptoms, and that anger moderates (increases) the risk associated with intense drinking. Methods: Data from Project MATCH, a multisite alcohol use disorders treatment trial, were analyzed using structural equation modeling. There were 1,726 participants including 24% women and a mean age of 40.2 +/- 11.0 years. Subjects were assessed at baseline and at 3-, 9-, and 15-month follow-up. Two categorical measures (presence/absence) of suicidal ideation (SI) were used that were analyzed in separate models. Predictors of interest were continuous assessments of average drinking intensity (i.e., drinks per drinking day or DDD), drinking frequency (i.e., percent days abstinent or PDA), depression, and anger. Results: Both DDD and PDA were associated with SI at a statistically significant level, with PDA showing an inverse association. Depression scores served as a partial mediator or a full mediator of the drinking-SI relationship depending on the measure of SI used in the analysis. The models testing anger scores as a moderator fit the data poorly and did not support that anger serves as a moderator of the drinking-SI association. Conclusions: Greater drinking intensity and drinking frequency predict SI among ADIs and depression serves as a mediator of these associations, but anger does not appear to serve as a moderator. Further research is required to clarify whether depression serves as a partial or full mediator and to see whether the results herein extend to suicidal behavior (i.e., suicide attempt, suicide).