Sunday is 420 day, a global event where enthusiasts celebrate their love for cannabis. Yet amidst the celebrations, emerging research casts a shadow on the presumed safety of marijuana. A new study published in JAMA Neurology highlights an alarming connection between cannabis use and dementia risk, revealing a 23% increased likelihood of developing dementia within five years for those hospitalised due to marijuana use compared to hospitalisations for other reasons.

The study examined over 6 million individuals in Ontario, Canada, and its findings emphasise the potential long-term cognitive effects of marijuana use—even for those who view it as a harmless, natural substance.

Cannabis Use and Dementia Risk Evidence Mounts

The study’s co-author, Dr Daniel Myran, assistant professor in family medicine at the University of Ottawa, explained the gravity of the findings. “Within five years of an emergency room visit or hospitalisation for cannabis, 5% of individuals received a dementia diagnosis,” he said. When compared to the general population, that number skyrockets to a shocking 72% greater risk.

Crucially, these numbers account for other potential causes, including age, heart disease, diabetes, and mental health conditions, making the pattern of cannabis use and cognitive decline even more concerning.

This research fits into a growing body of evidence exploring the health risks linked to marijuana, ranging from strokes and heart disease to myocarditis. Previous studies have reported that marijuana users are nearly 25% more likely to require emergency care or hospitalisation due to adverse effects.

However, Dr Myran asserts, “This isn’t definitive proof that cannabis causes dementia.” Instead, it is a call to attention for additional research to understand the connection further and determine causality.

The Rising Potency of Modern Cannabis

Cannabis has become increasingly potent over recent decades, broadening its psychotropic effects significantly. According to a 2022 analysis, escalating THC (tetrahydrocannabinol) levels have contributed to a global rise in cannabis use disorder (CUD) and addiction, affecting up to 30% of users.

CUD is marked by an inability to stop use despite negative health or social outcomes. Withdrawal symptoms like anxiety and depression are common, often causing hospitalisation after abrupt cessation.

The US Centres for Disease Control and Prevention (CDC) also highlights marijuana’s impact on brain health, linking regular use to memory challenges, learning difficulties, and attentional deficits. “Many people believe cannabis is natural and therefore safe,” said Dr Robert Page II, a clinical pharmacy professor at the University of Colorado. “However, it’s psychotropic and can exacerbate existing psychiatric conditions.”

A Global Health Warning

With emergency room visits related to marijuana use increasing fivefold between 2008 and 2021 among those aged 45 to 64, and an extraordinary 27-fold increase in individuals aged 65 and above, the data suggests an urgent need to reassess perceptions of cannabis safety in the UK and beyond.

If cannabis use and dementia risk are directly linked, how might marijuana affect the brain? Dr Myran proposes several possible mechanisms, including inflammation and microvascular damage. Regular users might also accrue risk factors indirectly, such as depression or social isolation, both known contributors to cognitive decline.

Indeed, data shows daily cannabis use now surpasses alcohol use in some demographics. The implication is significant, with marijuana potentially contributing to lifestyle behaviours that inadvertently increase dementia risk.

An Appeal to Prioritise Mental and Cognitive Health

Experts like Dr Page urge health professionals to routinely screen for cannabis use disorder and educate patients effectively. “Being aware of these risks and ensuring transparency with healthcare providers is crucial,” he advised.

Individuals should also reflect on their marijuana consumption patterns, weighing potential risks with the growing evidence. While the cultural perception of cannabis paints it as harmless, research suggests a more cautious stance is necessary to mitigate long-lasting cognitive damage.

Source: CNN