Faculty Collaboration Database

Impact of ADHD and cannabis use on executive functioning in young adults. Drug Alcohol Depend 2013 Dec 01;133(2):607-14

Date

09/03/2013

Pubmed ID

23992650

Pubmed Central ID

PMC3820098

DOI

10.1016/j.drugalcdep.2013.08.001

Scopus ID

2-s2.0-84887023333 (requires institutional sign-in at Scopus site)   57 Citations

Abstract

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) and cannabis use are each associated with specific cognitive deficits. Few studies have investigated the neurocognitive profile of individuals with both an ADHD history and regular cannabis use. The greatest cognitive impairment is expected among ADHD Cannabis Users compared to those with ADHD-only, Cannabis use-only, or neither.

METHODS: Young adults (24.2 ± 1.2 years) with a childhood ADHD diagnosis who did (n=42) and did not (n=45) report past year ≥ monthly cannabis use were compared on neuropsychological measures to a local normative comparison group (LNCG) who did (n=20) and did not (n=21) report past year regular cannabis use. Age, gender, IQ, socioeconomic status, and past year alcohol and smoking were statistical covariates.

RESULTS: The ADHD group performed worse than LNCG on verbal memory, processing speed, cognitive interference, decision-making, working memory, and response inhibition. No significant effects for cannabis use emerged. Interactions between ADHD and cannabis were non-significant. Exploratory analyses revealed that individuals who began using cannabis regularly before age 16 (n=27) may have poorer executive functioning (i.e., decision-making, working memory, and response inhibition), than users who began later (n=32); replication is warranted with a larger sample.

CONCLUSIONS: A childhood diagnosis of ADHD, but not cannabis use in adulthood, was associated with executive dysfunction. Earlier initiation of cannabis use may be linked to poor cognitive outcomes and a significantly greater proportion of the ADHD group began using cannabis before age 16. Regular cannabis use starting after age 16 may not be sufficient to aggravate longstanding cognitive deficits characteristic of ADHD.

Author List

Tamm L, Epstein JN, Lisdahl KM, Molina B, Tapert S, Hinshaw SP, Arnold LE, Velanova K, Abikoff H, Swanson JM, MTA Neuroimaging Group

Author

Krista Lisdahl PhD Assistant Professor in the Psychology department at University of Wisconsin - Milwaukee

MESH terms used to index this publication - Major topics in bold

Adolescent
Age Factors
Age of Onset
Attention Deficit Disorder with Hyperactivity
Child
Data Interpretation, Statistical
Executive Function
Female
Follow-Up Studies
Gambling
Humans
Male
Marijuana Abuse
Neuropsychological Tests
Sex Factors
Surveys and Questionnaires
Trail Making Test
Verbal Learning
Young Adult