The Potent Reality of Modern Cannabis: Stanford Experts Urge Caution for Older Adults

As cannabis legalization expands across the United States, a growing number of older Americans are turning to marijuana for various health concerns. However, experts at Stanford Medicine are sounding an alarm, emphasizing that today’s cannabis products are significantly more potent than those available decades ago and carry substantial health risks for this demographic. This surge in use, coupled with evolving product strengths, necessitates a closer examination of the potential impacts on the aging population.

The Shifting Landscape of Cannabis Use Among Seniors

The demographic of cannabis users is undergoing a significant transformation. While marijuana was once predominantly associated with younger generations, a notable increase in usage is now being observed among adults aged 65 and older. This trend is partly fueled by the growing accessibility of legal cannabis in many states for both medical and recreational purposes. According to the National Survey on Drug Use and Health, cannabis use among adults over 65 saw a rise from less than 5% in 2021 to 7% in 2023. This incremental yet steady growth highlights a developing public health consideration.

Eloise Theisen, a geriatric nurse practitioner specializing in cannabis therapy at Stanford Medicine, witnessed this shift firsthand. Initially turning to cannabis for her own chronic pain following a severe car accident, she later observed its use among patients in an oncology clinic. "I found that our patients were going to use it whether their providers approved of it or not," Theisen stated. "Many of our patients were older, and they had risks that needed to be evaluated and addressed before they started using cannabis." This personal and professional experience underscores the urgent need for medical guidance and informed decision-making among older adults considering cannabis.

The Unprecedented Potency of Today’s Cannabis

A critical factor driving the concern among Stanford experts is the dramatic increase in the potency of cannabis products. In the 1970s, marijuana typically contained between 1% and 4% tetrahydrocannabinol (THC), the primary psychoactive compound. Today, legal cannabis flower commonly averages around 20% THC, with some strains reaching as high as 35%. The potency escalation is even more pronounced in other product forms. Oils, edibles, and concentrates can contain THC levels approaching 90%.

"We’re trying to catch up in our understanding of how that drastic of an increase in the psychoactive ingredient is impacting the brain and the body," explained Claudia Padula, PhD, assistant professor of psychiatry and behavioral sciences at Stanford Medicine. This substantial leap in concentration means that individuals, particularly older adults who may have had prior exposure to much weaker forms of cannabis, are at a heightened risk of accidental overconsumption.

This increased potency has tangible consequences. A Canadian study analyzing emergency room visits before and after nationwide legalization revealed a near tripling of cannabis poisoning cases among adults over 65. "There are so many different formulations and so many different strengths," commented Smita Das, MD, PhD, clinical associate professor of psychiatry and behavioral sciences at Stanford Medicine. "This is really not the cannabis of the ’70s." The sheer variability in product strength and formulation presents a significant challenge for users seeking predictable and safe experiences.

Cardiovascular and Cognitive Risks Magnified in Older Adults

The potential health implications of regular cannabis use are a significant concern for older adults, especially concerning cardiovascular health and cognitive function. While research is ongoing, several studies have indicated a link between regular cannabis consumption and an increased risk of cardiovascular disease.

Joseph Wu, MD, PhD, director of the Stanford Cardiovascular Institute, highlighted this concern. "Heart disease remains the leading cause of death in the United States," he noted, emphasizing the heightened vulnerability of the older population. Dr. Wu’s research team has observed in animal studies that THC can trigger inflammation in blood vessels. Epidemiological research further supports this, connecting cannabis use in humans with a 29% increase in heart attack risk and a 20% increase in stroke risk.

It is crucial to note that these risks can be exacerbated by co-occurring behaviors. Many cannabis users also smoke cigarettes or consume alcohol, and the combined effect of these substances can amplify cardiovascular dangers. Furthermore, smoking cannabis has been associated with an increased risk of lung cancer and cancers of the head and neck. Dr. Wu pointed out that smoking and vaping cannabis appear to induce more inflammation than edible products, though edibles are not without their own risks. "There is no safe amount of cannabis. Low doses and occasional use are still associated with vascular inflammation," he stated. "Abstinence is the safest option for heart health."

Beyond cardiovascular concerns, older adults may also experience increased risks of dizziness, confusion, falls, and the exacerbation of cognitive issues, including dementia, when using cannabis. The physiological processes in older adults contribute to these heightened risks. They metabolize cannabis more slowly than younger individuals, meaning the drug can remain in the body longer, prolonging its effects and increasing the potential for adverse reactions.

The Insidious Nature of Cannabis Addiction

A prevalent misconception surrounding cannabis is its perceived lack of addictive potential. However, Dr. Das asserts that current research contradicts this notion. Studies suggest that approximately 30% of regular cannabis users may develop cannabis use disorder. This condition is characterized by a compulsive need for the drug, withdrawal symptoms, the requirement of higher doses to achieve the same effect, and interference with daily life, relationships, and responsibilities.

While cannabis addiction rates may be lower than those associated with alcohol, Dr. Das points out that many healthcare providers do not routinely inquire about cannabis use among older adults. "I’m noticing that older adults may not necessarily be disclosing cannabis use to their providers unless specifically asked. This isn’t a population we traditionally think about in terms of using cannabis," she observed. This lack of open communication can prevent timely identification and intervention for those struggling with problematic use.

For individuals seeking to reduce or cease their cannabis consumption, Dr. Das strongly advises open dialogue with a physician or addiction specialist. Therapies such as cognitive behavioral therapy have demonstrated efficacy in treating substance use disorders. "Empowering individuals by helping them understand the criteria of a substance use disorder can then help them decide, ‘Is this something I want to talk about?’" Dr. Das explained. "On the clinician side, we can do a lot to make substance use part of the conversation."

Dr. Padula’s ongoing research, which employs functional MRI scans, is exploring how the brain reacts to environmental cues in individuals with cannabis use disorder and other addictions. Her findings indicate that individuals who relapse after treatment often exhibit heightened sensitivity to drug-related stimuli in their environment, a factor that could be particularly relevant for older adults navigating the complexities of addiction.

The Nuance of Medical Efficacy and Limited Evidence

While the risks associated with potent cannabis products are significant, the potential therapeutic benefits for certain conditions remain a subject of ongoing research and debate. Different age groups, as observed in a 2017 study led by Dr. Padula, tend to use cannabis for distinct reasons. Younger adults (18-30) were more likely to use it for boredom or social purposes, middle-aged users frequently cited insomnia, while older adults (51-72) often reported using cannabis for cancer-related symptoms, chronic pain, or other long-term medical conditions.

The Food and Drug Administration (FDA) has not approved cannabis itself for general medical treatment. However, two cannabis-related compounds have received FDA approval: CBD for specific forms of childhood epilepsy, and dronabinol, a synthetic cannabis compound, for managing nausea and appetite loss in patients undergoing cancer treatment or living with HIV/AIDS. Additionally, cannabis compounds have shown promise in alleviating muscle spasms associated with multiple sclerosis, a condition for which some countries have approved cannabis, though not the United States.

Despite the widespread marketing of CBD products for a range of ailments including pain, sleep disturbances, anxiety, and substance use disorders, robust scientific evidence supporting many of these claims remains limited. Research into cannabis for chronic pain has yielded mixed results, with some studies indicating pain relief alongside significant placebo effects. The American Psychiatric Association, with input from Dr. Das, has issued statements opposing the use of cannabis as a psychiatric treatment due to a lack of conclusive evidence for its efficacy in treating psychiatric disorders.

Eloise Theisen, however, offers a different perspective from her work with palliative care patients facing life-limiting illnesses. She notes that many of these patients utilize cannabis to manage cancer-related symptoms, particularly pain, and often seek alternatives to opioid medications, which carry their own risks of serious side effects and addiction. Research has indicated that patients with chronic pain who use cannabis sometimes reduce their opioid intake. Furthermore, Theisen observes that cannabis can provide a sense of well-being. "THC has gotten a bad rap over the years, but in very small doses it can be therapeutic," she commented. "There’s also a lot of stigma around its effects of euphoria. In our patients who may have months to a few years to live, still being able to experience joy is really important." This highlights the potential for nuanced applications of cannabis, particularly in end-of-life care, where the quality of life is a paramount concern.

The Imperative of Open Dialogue with Healthcare Providers

Across the spectrum of opinions regarding cannabis’s medical utility, Stanford experts universally agree on one crucial point: older adults must engage in honest and open conversations with their healthcare providers before using cannabis. Theisen strongly advocates for patients to seek guidance from medical professionals rather than relying on information from dispensary staff or self-experimentation.

In the early years of legalization, Theisen frequently encountered patients who had inadvertently consumed dangerously high doses of THC edibles due to a lack of proper instructions. "Patients would sometimes end up in the emergency department, or they would not want to take it again because they thought, ‘This isn’t going to work for me,’" she recounted. This underscores the vital role of professional guidance in navigating the complexities of cannabis products.

Reliable and accurate information about cannabis remains a challenge to access. Healthcare providers are best positioned to help patients assess the appropriateness of cannabis use, explore potential alternatives, and identify risks associated with existing medical conditions and current medications. "Your primary care physician will know the constellation of your medical conditions and other medications you might be on," emphasized Dr. Padula. "Talking to your doctor and letting them know not only what you’re prescribed, but what you’re using recreationally, will help formulate a way to do it in as safe a manner as possible." This collaborative approach is essential for ensuring the safety and well-being of older adults as they consider or continue their use of cannabis.