Comorbid Substance Abuse and Mental Illness on Impulsivity

Abstract

Introduction: Impulsivity, or a lack of self-control, has been identified as a significant risk factor in individuals with substance abuse. Several studies have shown that the impact of impulsivity affects the onset of substance abuse, relapsing substance abuse, and outcomes during substance abuse treatment. Impulsivity has also been defined as a trait characteristic in multiple psychiatric disorders (i.e. schizophrenia, depression). Furthermore, studies have identified impulsivity as a mediating factor between psychiatric disorders and mental illness. Methods: Eligible participants were identified by practitioners at the Augusta University Psychiatry and Health Behaviors outpatient clinic and Serenity Behavioral Health Systems (n=47). Participants were administered the UPPS-short and BIS-11 scales via phone interviews. Follow-up phone interviews were conducted 30 days after the initial interview to establish test-retest validity. Of those that completed the initial assessment, 31 participants completed the follow-up assessment. Results: When comparing the UPPS and BIS scores in substance abusers and non-substance abusers, scores were higher in the substance abuse group compared to the non-substance abuse group, although this difference did not achieve significance (p = 0.19 and p = 0.43, respectively). UPPS and BIS scores correlated significantly with each other at initial assessment (r=0.79, p<0.001) and follow-up (r=0.82, p<0.001). The initial assessments of the UPPS and BIS also correlated significant with the follow-up assessments (r=0.74, p<0.001 and r=0.83, p<0.001, respectively). Conclusion: Results of the study indicate that impulsivity was higher in the substance abusing sample compared to the non-substance abusing sample, although significance was not reached. A decreased p-value in the entire sample as compared to previous analyses performed on a partial sample suggests that the current sample lacks power. Increased sample size may allow for the analyses to reach significance.