As cannabis use continues its upward trajectory among Americans aged 65 and older, a growing chorus of concern is emerging from medical professionals, particularly those at Stanford Medicine. Experts are issuing a stark warning: today’s cannabis products are significantly more potent than the marijuana many older adults may have encountered in their youth, and this increased strength, coupled with age-related physiological changes, can lead to substantial and often underestimated health risks.
This evolving landscape necessitates a deeper understanding of how modern cannabis interacts with the aging body and brain. Eloise Theisen, a geriatric nurse practitioner specializing in cannabis therapy at Stanford Medicine, found herself at the forefront of this issue almost by accident. Her personal journey with chronic pain, stemming from a severe car accident, led her to explore cannabis as a last resort when conventional treatments proved ineffective. It was during her subsequent return to an oncology clinic that she observed a pervasive trend: patients were increasingly turning to cannabis, often without professional guidance, to manage their symptoms.
"I found that our patients were going to use it whether their providers approved of it or not," Theisen recounted. "Many of our patients were older, and they had risks that needed to be evaluated and addressed before they started using cannabis." This realization underscored a critical gap in patient care and highlighted the urgent need for informed medical discourse surrounding cannabis use in the senior population.
The Shifting Landscape of Cannabis Potency
The rise in cannabis consumption among older adults is occurring against a backdrop of evolving legal statuses and dramatically increased potency. While medical marijuana is now legal in 40 states and the District of Columbia, and recreational cannabis in 24 states and D.C., the very nature of the plant has transformed. Data from the National Survey on Drug Use and Health reveals a notable uptick in recent cannabis use among adults over 65, climbing from less than 5% in 2021 to 7% in 2023. This demographic, often managing multiple chronic conditions and taking various prescription medications, is particularly vulnerable to the effects of potent psychoactive compounds.
The primary driver of this concern is the significant increase in tetrahydrocannabinol (THC) levels. In the 1970s, marijuana typically contained between 1% and 4% THC, the compound responsible for the drug’s intoxicating effects. Today, legal cannabis flower averages around 20% THC, with some strains reaching as high as 35%. The potency escalates further with other product forms. Oils, edibles, and concentrates can boast THC levels approaching 90%. Synthetic marijuana products, such as spice or K2, which are illegal in California and many other states, are even more concentrated and have been linked to severe adverse health events, including heart problems.
"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," stated Claudia Padula, PhD, assistant professor of psychiatry and behavioral sciences at Stanford Medicine. This dramatic surge in THC concentration is not merely an academic concern; it has tangible public health implications. A Canadian study analyzing emergency room visits before and after nationwide cannabis legalization found that cases of cannabis poisoning among adults over 65 nearly tripled. This suggests a direct correlation between increased potency and accidental overconsumption, particularly among individuals less familiar with the heightened effects of modern products.
"There are so many different formulations and so many different strengths," emphasized Smita Das, MD, PhD, clinical associate professor of psychiatry and behavioral sciences at Stanford Medicine. "This is really not the cannabis of the ’70s."
Cardiovascular and Cognitive Concerns for Seniors
One of the most significant areas of concern for Stanford Medicine experts is the potential impact of regular cannabis use on cardiovascular health, especially for older adults, where heart disease remains the leading cause of death in the United States. Joseph Wu, MD, PhD, director of the Stanford Cardiovascular Institute, highlighted research that links regular cannabis use to an increased risk of cardiovascular events. His team’s animal studies have shown that THC can trigger inflammation in blood vessels. Epidemiological research in humans has further connected cannabis use with a higher incidence of heart attacks and strokes, with studies suggesting a 29% increase in heart attack risk and a 20% increase in stroke risk associated with regular use.
While these risks may be lower than those associated with heavy tobacco or alcohol consumption, Dr. Wu cautioned that many cannabis users also engage in these other behaviors. The synergistic effect of combining substances could further amplify cardiovascular dangers. Moreover, smoking cannabis, similar to smoking tobacco, has been associated with an increased risk of lung cancer and cancers of the head and neck. Dr. Wu’s research indicates that smoking and vaping cannabis may promote more inflammation than edible products, although 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," Dr. Wu asserted. "Abstinence is the safest option for heart health."
Beyond cardiovascular issues, Theisen also observes other complications in older patients who use cannabis, including dizziness, confusion, falls, and the exacerbation of cognitive problems, such as dementia. The physiological differences in older adults contribute to these heightened risks. They metabolize cannabis more slowly than younger individuals, meaning the drug can remain in the system longer, leading to prolonged and potentially unexpected effects. This slower metabolism also increases the likelihood of dangerous interactions with prescription medications.
A pertinent example involves cannabidiol (CBD), a non-intoxicating cannabis compound. CBD can interfere with enzymes responsible for metabolizing certain medications, including blood thinners. This interference can lead to elevated drug levels in the body, increasing the risk of bleeding, particularly after an injury or fall. In some instances, cannabis use can also diminish the effectiveness of essential medications.
The Underrated Risk of Addiction
A pervasive misconception is that cannabis is not addictive. However, Dr. Das firmly refutes this notion, citing research that indicates approximately 30% of regular cannabis users may develop cannabis use disorder. This disorder is characterized by the drug’s significant impact on an individual’s daily life, manifesting as withdrawal symptoms, a need for escalating doses over time, or cannabis interfering with relationships and responsibilities.
While cannabis addiction rates are generally lower than those for alcohol, Dr. Das pointed out a critical oversight in healthcare: many providers may 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," she observed. "This isn’t a population we traditionally think about in terms of using cannabis." This lack of open dialogue means that many seniors struggling with cannabis use disorder may not receive the support and treatment they need.
For individuals seeking to reduce or cease their cannabis use, Dr. Das emphasizes the importance of open communication with a doctor or addiction specialist. Evidence-based treatments, such as cognitive behavioral therapy, have demonstrated efficacy in managing 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 suggested. "On the clinician side, we can do a lot to make substance use part of the conversation. What are they using the cannabis for? And if somebody wants to stop using, we need to stick with them through the difficult part of stopping."
Dr. Padula’s ongoing research into how the brain responds to environmental cues in individuals with cannabis use disorder and other addictions is shedding further light on the mechanisms of relapse. Her work, utilizing functional MRI scans, has revealed that individuals who relapse after treatment often exhibit heightened sensitivity to drug-related signals in their surroundings, underscoring the complex nature of addiction and the need for comprehensive support.
Navigating the Therapeutic Potential and Research Gaps
The therapeutic applications of cannabis remain a complex and evolving area of research. While the Food and Drug Administration (FDA) has not approved cannabis itself for medical treatment, it has approved two cannabis-related compounds: CBD for specific forms of childhood epilepsy and dronabinol, a synthetic compound, for managing nausea and appetite loss in patients undergoing cancer treatment or living with HIV/AIDS. Furthermore, cannabis compounds have shown promise for alleviating muscle spasms associated with multiple sclerosis, leading to approvals in some countries, though not yet in the United States.
Research into cannabis for chronic pain has yielded mixed results. Some studies report pain relief, while others highlight significant placebo effects. The American Psychiatric Association, with input from researchers like Dr. Das, has issued statements opposing cannabis as a psychiatric treatment due to a current lack of robust evidence demonstrating its effectiveness for psychiatric disorders.
However, Theisen’s work with palliative care patients facing life-limiting illnesses offers a nuanced perspective. Many of her patients utilize cannabis to manage cancer-related symptoms, particularly pain, often seeking alternatives to opioid medications, which carry their own risks of serious side effects and addiction. Evidence suggests that patients with chronic pain who use cannabis may reduce their opioid consumption. Additionally, Theisen notes that many patients find cannabis contributes to a sense of well-being. "THC has gotten a bad rap over the years, but in very small doses it can be therapeutic," she explained. "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 cannabis to improve quality of life in specific, medically supervised contexts.
The Imperative of Open Communication with Healthcare Providers
Despite the ongoing debates about its medical utility, a consensus among Stanford Medicine experts is clear: older adults should engage in open and honest conversations with their healthcare providers before using cannabis. Theisen strongly advocates for patients to seek guidance from medical professionals rather than relying on advice from dispensary staff or experimenting independently. She has frequently encountered instances where patients have accidentally consumed excessively high doses of THC edibles due to a lack of proper instructions, leading to negative experiences and a reluctance to reconsider cannabis.
"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 recalled. Accurate and reliable information about cannabis can be challenging to obtain, making the role of healthcare providers even more crucial. Doctors can assist patients in evaluating the appropriateness of cannabis for their specific needs, explore alternative treatment options, and identify potential risks related to existing medical conditions or current medications.
"Your primary care physician will know the constellation of your medical conditions and other medications you might be on," Dr. Padula advised. "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 ensures that informed decisions can be made, prioritizing the health and safety of older adults as they navigate the increasingly complex world of cannabis. The implications of this growing trend extend beyond individual health, prompting a broader societal conversation about responsible cannabis use, effective public health messaging, and the need for continued, comprehensive research to inform both patient care and public policy.
