Impulsivity Impacts Suicidality in Patients with Alcohol Use Disorder with and without Comorbid Depression

Objective: The independent rôle of impulsivity in alcoholism patient’s suicidality is less elucidated. In this study, we intended to investigate how impulsivity and depression contribute to suicidality in patients with alcohol use disorder (AUD). Methods: We recruited 27 adult patients with AUD and major depressive disorder (AUD with MDD) and 33 with AUD only (AUD without MDD). We assessed suicidality, alcohol use severity, depression severity, impulsivity, and other psychiatric comorbidities. Suicidality was quantified for the frequency of previous history of suicide attempts and for current suicide intent/tendency. Impulsivity was measured using the Barratt Impulsiveness Scale (BIS). We addressed how impulsivity contributed to both suicidality indices in multiple ordinal regressions. Results: Patients with AUD with MDD versus those with AUD without MDD showed significantly higher suicidality (p < 0.001), significantly more severe alcohol (p < 0.01), significantly more polysubstance use (p < 0.05), significantly more anxiety comorbidities (p < 0.05), and significantly higher BIS scores (p < 0.001). In a better-fitting final model using regression with stepwise elimination, the BIS total score was independently and significantly associated with current suicide tendency (p < 0.05) and frequency of previous suicide attempts (p < 0.01). In contrast, the Hamilton Depression Rating Scale-17 score was significantly associated only with current suicidal tendencies (p < 0.01), but not with the frequency of previous attempts. Conclusion: Depressed patients relative to nondepressed individuals with AUD showed higher suicidality, Barratt impulsivity, and severity of alcohol use. Across groups, BIS impulsivity but not the severity of depression was found to predict suicidality. We suggest that suicide prevention efforts may include assessment of impulsivity in AUD patients.