The Effects of Cannabis Use on Cognitive Function in Healthy Aging: A Systematic Scoping Review. (7th November 2020)

• Record Type: Journal Article
• Authors: Pocuca, Nina; Walter, T Jordan; Minassian, Arpi; Young, Jared W; Geyer, Mark A; Perry, William
• Is Part Of: Archives of clinical neuropsychology. Volume 36:Number 5(2021)
• Page Start: 673
• Page End: 685
• Publication Date: 2020-11-07
• Subjects: Older adult -- Cannabis -- ∆9-Tetrahydrocannabinol -- Cannabidiol -- Cognitive function; Clinical neuropsychology -- Periodicals; 616.805
• DOI: 10.1093/arclin/acaa105
• Languages: English
• ISSNs: 0887-6177

Abstract

Abstract: Background: Older adults (≥50 years) represent the fastest-growing population of people who use cannabis, potentially due to the increasing promotion of cannabis as medicine by dispensaries and cannabis websites. Given healthy aging and cannabis use are both associated with cognitive decline, it is important to establish the effects of cannabis on cognition in healthy aging. Objective: This systematic scoping review used preferred reporting items for systematic reviews and meta-analyses guidelines to critically examine the extent of literature on this topic and highlight areas for future research. Method: A search of six databases (PubMed, EMBASE, PsycINFO, Web of Science, Family and Society Studies Worldwide, and CINAHL) for articles published by September 2019, yielded 1, 014 unique results. Results: Six articles reported findings for older populations (three human and three rodent studies), highlighting the paucity of research in this area. Human studies revealed largely null results, likely due to several methodological limitations. Better-controlled rodent studies indicate that the relationship between ∆9-tetrahydrocannabinol (THC) and cognitive function in healthy aging depends on age and level of THC exposure. Extremely low doses of THC improved cognition in very old rodents. Somewhat higher chronic doses improved cognition in moderately aged rodents. No studies examined the effects of cannabidiol (CBD) or high-CBD cannabis on cognition. Conclusions: This systematic scoping review provides crucial, timely direction for future research on this emerging issue. Future research that combines neuroimaging and cognitive assessment would serve to advance understanding of the effects of age and quantity of THC and CBD on cognition in healthy aging.