Neurocognition and inhibitory control in polysubstance use disorders: Comparison with alcohol use disorders and changes with abstinence

ABSTRACT

Introduction: Intact neurocognition and early cognitive recovery during abstinence are important for substance use treatment outcome. Yet, little is known about them in the largest group of treatment seekers today, individuals with polysubstance use disorders (PSU). This study primarily contrasted PSU and individuals with an alcohol use disorder (AUD) on neurocognitive and inhibitory control measures and, secondarily, measured changes during abstinence in PSU. Method: At one month of abstinence from all substances except tobacco, 36 PSU and 69 AUD completed neurocognitive assessments of executive function, general intelligence, auditory–verbal learning/memory, visuospatial learning/memory/skills, processing speed, working memory, fine motor skills, and cognitive efficiency. The groups were also assessed on inhibitory control measures of self-reported impulsivity, risk-taking, and decision-making. Seventeen PSU repeated the assessments after approximately four months of abstinence. All cross-sectional and longitudinal analyses included smoking status as a possible confound. Results: At baseline, PSU performed significantly worse than AUD on auditory–verbal memory and on an inhibitory control measure of impulsivity. Polysubstance users showed trends to worse performance than AUD on general intelligence, auditory–verbal learning, and a decision-making task. Between one and four months of abstinence, PSU showed significant improvements on several neurocognitive and inhibitory control measures. Conclusions: Polysubstance users exhibit distinct differences in neurocognition and inhibitory control compared to AUD. Between one and four months of abstinence, neurocognition and inhibitory control improve in PSU. This neurocognitive recovery in some domains of abstinent PSU is influenced by smoking status. These results underscore the clinical value of select methods to augment neurocognitive recovery in PSU through appropriate interventions.

KEYWORDS:

• Addiction
• Cognition
• Impulsivity
• Longitudinal
• Recovery
• Substance use disorders

Acknowledgments

The authors have no financial or any other personal conflicts with this study. We thank Mary Rebecca Young, Kathleen Altieri, Ricky Chen, Christopher Galloway, and Julia Madsen, Peter Banys, Steven Batki, and Ellen Herbst of the San Francisco Veterans Administration Medical Center Intensive Outpatient Program, and David Pating, Karen Moise, Rosaleen Shelley, and their colleagues at the Kaiser Permanente Chemical Dependency Recovery Program in San Francisco California for their valuable assistance in recruiting participants. We also wish to extend our gratitude to the study participants who made this research possible.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Institutes of Health [grant number AA10788 to D.J.M.], [grant number DA25202 to D.J.M.], [grant number DA21436 to T.C.D.], administered by the Northern California Institute for Research and Education; and by the use of resources and facilities at the San Francisco Veterans Administration Medical Center.