Low Dose THC May Improve Cognitive Function in the Elderly

As cannabis gains traction as a medicinal option, particularly among older adults (≥50 years), concerns about its potential effects on cognitive function in healthy aging have surfaced. A recent systematic review, conducted in line with the preferred reporting items for systematic reviews and meta-analyses guidelines, aimed to delve into the existing literature and identify areas requiring further investigation.

Methodology

A thorough search across six databases (PubMed, EMBASE, PsycINFO, Web of Science, Family and Society Studies Worldwide, and CINAHL) was conducted, yielding a total of 1,014 unique results from articles published until September 2019.

Key Findings

• The review spotlighted a striking scarcity of research on cannabis's impact on cognition in healthy aging, with only six articles identified for older populations (three human and three rodent studies).
• Human studies predominantly reported null results, attributing limitations in methodology to these outcomes.
• Rodent studies, offering better control, suggested that the relationship between ∆9-tetrahydrocannabinol (THC) and cognitive function in healthy aging hinges on age and THC exposure levels. Notably, extremely low THC doses exhibited cognitive improvements in very old rodents, while somewhat higher chronic doses enhanced cognition in moderately aged rodents.
• Intriguingly, no studies within the scope examined the effects of cannabidiol (CBD) or high-CBD cannabis on cognition in healthy aging.

Conclusion

This systematic scoping review serves as a vital compass for future research on the intersection of cannabis use and cognitive function in healthy aging. The findings underscore the necessity for more nuanced investigations, suggesting that future research could benefit from combining neuroimaging techniques with cognitive assessments. This holistic approach promises to advance our understanding of how age and the quantity of THC and CBD may influence cognition in the context of healthy aging. As cannabis continues to be explored for its medicinal potential, these insights will prove invaluable in shaping a comprehensive understanding of its effects on cognitive health in older populations.