Accepted for/Published in: JMIR Research Protocols
Date Submitted: Feb 20, 2020
Open Peer Review Period: Feb 20, 2020 - Mar 22, 2020
Date Accepted: Apr 14, 2020
(closed for review but you can still tweet)
Warning: This is an author submission that is not peer-reviewed or edited. Preprints - unless they show as "accepted" - should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.
Association between early cannabis and illicit drug use and neurodevelopment, including structural, functional and cognitive outcomes: A systematic review protocol
ABSTRACT
Background:
Illicit drug use and associated harms are highest among young people aged 15-24 years, coinciding with the final stages of neurodevelopment and a period of high neuroplasticity. It is likely that frequent drug use during this time can interfere with fundamental neurophysiological and neuropsychological development pathways and could lead to ongoing unfavourable neuroadaptations. To date, the dose-response relationship between types of illicit drug use, degree of exposure and individual variation is unknown. This is particularly salient due to the shifting legal landscape around drugs such as cannabis and the corresponding liberalisation of attitudes towards the perception of harm.
Objective:
This systematic review aims to synthesise longitudinal studies that investigate the effects of illicit drug use on structural, functional and cognitive brain domains in individuals under the neural age of adulthood, being 25years. This protocol outlines prospective methods that will facilitate an exhaustive review of the literature exploring pre- and post- drug use brain abnormalities arising during neurodevelopment.
Methods:
Five electronic databases (Medline, Embase, PsycINFO, ProQuest Central and Web of Science) will be systematically searched between 1990 and 2020. The search terms will be a combinations of MeSH keywords adapted to each database. Study reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and study quality will be assessed using The Grades of Recommendation, Assessment, Development and Evaluation approach. The included studies will be screened against eligibility criteria designed to synthesise studies that considered a sample if youth with exposure to illicit drugs and employed neurobiological, neuropsychological or neuroimaging assessment techniques. Studies will be excluded if participants had been clinically diagnosed with any psychiatric, neurological or pharmacological condition.
Results:
This is an ongoing review. As of February 2020, papers are in full text screening with results predicted to be complete by July 2020.
Conclusions:
Integrating the three sources of data will enable an assessment of the links between structural, functional and cognitive brain health across individuals and may support the early detection and prevention of neurodevelopmental harm.
Citation
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Copyright
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