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A Systematic Review of the Neurocognitive Effects of Cannabis Use in Older Adults

  • Cannabis (A McRae-Clark and B Sherman, Section Editors)
  • Published:
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Abstract

Purpose of Review

Older adults currently represent the fastest growing demographic of cannabis users, yet few studies have investigated the effects of cannabis use on cognitive functioning in aging. We conducted a systematic review of the recent literature examining cognitive outcomes associated with cannabis use in older adults, with and without neurocognitive disorders, to clarify the potential neuroprotective benefits or risks of cognitive decline in this population.

Recent Findings

We identified 26 studies examining cognitive outcomes associated with medical and recreational use of cannabis in healthy aging, dementia, Parkinson’s disease, multiple sclerosis, HIV, and pain populations. Although variability in the cannabis products used, outcomes assessed, and study quality limits the conclusions that can be made, modest reductions in cognitive performance were generally detected with higher doses and heavier lifetime use.

Summary

This review highlights the need for additional high-quality research using standardized, validated assessments of cannabis exposure and cognitive outcomes. Reliable measures and longitudinal data are necessary to better characterize the effects of cannabis use on cognitive aging, as well as differential effects of recreational and medical cannabis.

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References

Papers of particular interest, published recently, have been highlighted as: • Of importance

    No studies of major importance were identified; the highest quality studies included in this review either did not directly address cognitive outcomes or did not focus on older adults.

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    1. Department of Neurology, Medical University of South Carolina, 96 Jonathan Lucas Street, MSC 323, Charleston, SC, 29425, USA

      Emmi P. Scott & Andreana Benitez

    2. Medical University of South Carolina Library, Charleston, South Carolina, USA

      Emily Brennan

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    Scott, E.P., Brennan, E. & Benitez, A. A Systematic Review of the Neurocognitive Effects of Cannabis Use in Older Adults. Curr Addict Rep 6, 443–455 (2019). https://doi.org/10.1007/s40429-019-00285-9

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