A systematic review was undertaken (1):
- conducted a comprehensive systematic search of the recent literature on cognitive outcomes associated with cannabis use and cannabinoids in adults age 50 and older
- revealed that there is evidence of modest negative effects on cognition in this population
- the study authors noted that "...larger controlled trials using validated outcome measures are greatly needed to better understand the role of cannabinoids in cognitive aging, as small sample sizes and variability in study designs limit our ability to draw definitive conclusions at this time.."
A study found that individuals with incident acute care due to cannabis use had a significantly higher risk of dementia diagnosis within 5 years compared to those with all-cause acute care and the general population (2)
- in this cohort study of 6 million individuals aged 45 years or older with no history of dementia, those with acute care due to cannabis use were at 1.5-fold (absolute risk, 5.0% vs 3.6%) and 3.9-fold (absolute risk, 5.0% vs 1.3%) increased risk of a new dementia diagnosis within 5 years compared with individuals with an all-cause acute care encounter and the general population, respectively
- study authors suggested:
- individuals with cannabis use severe enough to require emergency department or hospital care may be at increased risk of being diagnosed with dementia.
Reference:
- Scott EP, Brennan E, Benitez A. A Systematic Review of the Neurocognitive Effects of Cannabis Use in Older Adults. Curr Addict Rep. 2019 Dec;6(4):443-455.
- Myran DT, Pugliese M, Harrison LD, Stall NM, Webber C. Risk of Dementia in Individuals With Emergency Department Visits or Hospitalizations Due to Cannabis. JAMA Neurol. Published online April 14, 2025.