Cannabis Use Characteristics Associated with Self-Reported Cognitive Function in a Nationally Representative U.S. sample

Abstract

Background

With increases in cannabis use and potency, there is a need to improve our understanding of the impact of use on cognitive function. Previous research indicates long-term cannabis use may have a negative effect on executive function. Few studies have examined persistence of it in protracted abstinence, and there is limited evidence of predictors of worse cognitive function in current and former users. In this study, we aim to evaluate the associations between cannabis use status (current, former, and never use) and self-report cognition. Further, we investigate if cannabis use characteristics predict self-report cognitive function.

Methods

Cross-sectional cannabis use data from the National Epidemiological Survey on Alcohol and Related Conditions-III (NESARC-III), a national survey (N = 36,309) conducted in the USA between 2012 and 2013 were used alongside the Executive Function Index scales. The data were analyzed by using Ordinary Least Squares regression.

Results

Current (N = 3,681, Female = 37.7%) and former users (N = 7,448, Female = 45.4%) reported poorer cognition than never users (N = 24,956, Female = 56.6%). Self-reported cognition of former users was in-between that of current and never users. Several cannabis use characteristics were associated with self-reported cognition in current and former users.

Conclusion

While prospective studies are required to confirm, findings suggest cannabis use is linked to worse cognition. There may be some limited recovery of cognition in former users and some cannabis use characteristics predict impairment. These findings add to our understanding of the cognitive impact of cannabis use. As worse cognitive function may impact relapse, findings have implications for personalization of cannabis use disorder treatment.

Keywords:

• Abstinence
• attention
• cognition
• executive function
• cannabis
• NESARC-III

Disclosure statement

Dr. Bernard Le Foll has obtained funding from Pfizer Inc. (GRAND Awards, including salary support) for investigator-initiated projects. Dr Le Foll has obtained funding from Indivior for a clinical trial sponsored by Indivior. Dr. Le Foll has in-kind donations of cannabis products from Aurora Cannabis Enterprises Inc. and study medication donations from Pfizer Inc. (varenicline for smoking cessation) and Bioprojet Pharma. He was also provided a coil for a Transcranial magnetic stimulation (TMS) study from Brainsway. Dr. Le Foll has obtained industry funding from Canopy Growth Corporation (through research grants handled by the Centre for Addiction and Mental Health and the University of Toronto), Bioprojet Pharma, Alcohol Countermeasure Systems (ACS), Alkermes and Universal Ibogaine. Lastly, Dr. Le Foll has received in kind donations of nabiximols from GW Pharmaceuticals for past studies funded by CIHR and NIH.He has participated in a session of a National Advisory Board Meeting (Emerging Trends BUP-XR) for Indivior Canada and is part of Steering Board for a clinical trial for Indivior. He has been consultant for Shinogi. He got travel support to attend an event by Bioprojet. He is supported by CAMH, Waypoint Centre for Mental Health Care, a clinician-scientist award from the department of Family and Community Medicine of the University of Toronto and a Chair in Addiction Psychiatry from the department of Psychiatry of University of Toronto. Rubin-Kahana receives salary support from the O’Brien Scholars Program within the Child and Youth Mental Health Collaborative at CAMH and the Hospital for Sick Children, Toronto. Dr. Rubin-Kahana, Dr. Butler, Mr. Sanches and Dr. Hassan declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Notes

1 The different race/ethnicity groups followed the data presented in NESARC (National Institute on Alcohol Abuse and Alcoholism). For individuals who identify themselves as multiracial, a single race is selected in the following order of preference: (1) Black or African American (2) American Indian or Alaska Native (3) Native Hawaiian or Other Pacific Islander (4) Asian (5) White. For example, an individual who chooses Black and Asian will be classified as Black.

2 The different age groups were based on different life stages: 18-29: early young adulthood, 30-39: late young adulthood, 40-64: middle adulthood and 65-90: late adulthood.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.