Medical Cannabis Use in Older Adults

Background

As of 2021, thirty-six states, the District of Columbia, Guam, Puerto Rico, and the U.S. Virgin Islands have medical cannabis programs; according to the National Conference of State Legislatures eleven other states allow the use of low dose THC for medical purposes (https://www.ncsl.org/bookstore/state-legislatures-magazine/marijuana-deep-dive.aspx). Given the growing acceptance of its use in medicine, the responsibility falls to medical providers of various professions (MD, APP, RN, SW, MA among many) to offer safe certification and education. For now, cannabis is not covered by insurance and therefore is not prescribed by physicians. For patients to experience effective use, they rely on psychoeducation by providers and dispensary patient navigators. This is more important in the older adult population due to polypharmacy, health literacy, and accessibility of the application process and dispensary locations.

Evidence for Use

Medical cannabis has increasing evidence to support its use in chronic and cancer-related pain management (Walsh, et al. 2013; National Academies of Sciences, Engineering, and Medicine 2017). Anecdotal evidence from a large urban academic medical center shows a growing interest in medical cannabis for our older adult population. The Rush University Medical Center Palliative Care outpatient clinic cares for patients with chronic pain and other symptoms related to chronic illness. 50% of its patients are Caucasian, 47% African American, 3% Asian, and 10.8% Hispanic. Its patients range in age from 19 to 91 (O’Mahony et al. 2018).

Research has shown that patients between the ages of 65 and 84 are comfortable with utilizing cannabis or have used it recreationally in the recent past; furthermore, of the respondents, 61% used cannabis for the first time aged 61 or older (Yang, et al. 2021). However, the vast majority of these patients do not feel comfortable bringing it up with medical providers and received most of their information from non-medical supports (Baumbusch, et al. 2020; Yang, et al. 2021). This leaves the medical teams to initiate the discussion. In a systematic review conducted by Gardiner et al., all studies undergoing full review indicated healthcare providers supported the use of medical cannabis, however felt ill-equipped with minimal knowledge surrounding “all aspects of medicinal cannabis” (Gardiner, et al. 2019). Because many symptoms treated by palliative care providers such as pain, nausea, and poor appetite are indications for medical cannabis, these palliative professionals have a unique opportunity to open this dialogue. This also means that they have the responsibility to set the patient up with a strong foundation for safe and effective cannabis use by using an interdisciplinary approach for the assessment of patient appropriateness.

Few randomized controlled trials (RCTs) have focused on medical cannabis for the older adult population. In total, existing RCTs have included fewer than 250 older adults. Low to moderate evidence suggests medical cannabis effectively reduces pain, particularly at the 30% level relative to pre-intervention pain. Studies assessing tolerability and safety report higher rates of mild adverse events and study withdrawal due to treatment-related side effects in participants receiving Cannabinoids (Levy C 2020).

Medical providers are hesitant to endorse the use of medical cannabis due to concerns about the contradictory findings in the available research related to the efficacy of medical cannabis for common reasons such as chronic pain, loss of appetite, weight loss, and nausea in cancer and HIV patients. The Federal government’s continued criminalization of cannabis is in part to blame for this limitation in research. In states where recreational cannabis and medical cannabis are legal, there is evidence of reductions in opioid overdose deaths. There is also evidence that the use of opioids declines significantly for medical cannabis users (Cyr 2019). There is evidence that there are lower rates of depression in patients who use medical cannabis for chronic pain versus patients who use either opioids alone or in combination with medical cannabis (Daniel Feingold et al. J Affect Disord. 2017).

Dosing recommendations for cannabis remain not robustly evidence-based, however, some states have defined a standard dose of THC per serving of edible product (e.g., 10 mg in Washington, California, and Colorado; 5 mg in Oregon).

Illinois Cannabis Programs

The Compassionate Use of Medical Cannabis Program has been around since 2013 (https://dph.illinois.gov/topics-services/prevention-wellness/medical-cannabis). The aim of this program is to assist patients with chronic, debilitating, or other qualifying conditions. The other, called the Opioid Alternative Pilot Program, is an opioid-sparing cannabis program; eligibility is based on appropriateness for or prescription of opioid medication (https://dph.illinois.gov/topics-services/prevention-wellness/medical-cannabis/opioid-alternative-pilot-program). For both programs, applicants require access to a computer, mobility to obtain a passport photo, accessibility of a dispensary, and financial means. This can be restrictive for some patients, especially older adults who do not have the financial means or the technological abilities to complete the application process. Finally, a patient should be certified for the programs that best fit their needs. Criteria will likely be different in each state. In Illinois, there are two programs for medical cannabis each with a different focus and intent.

Process for Determining Appropriateness

In our clinic at Rush University Medical Center, patients complete an initial evaluation upon each new patient visit, which includes MD/APP, RN, and SW. Patients are expected to complete a palliative care treatment agreement and Opioid Risk Tool (Webster et al. 2005). From there, each member of the team evaluates based on their specialty’s expertise in best practices for patient care and education.

Social work’s strength-based assessment includes caregiver support, interest in medical cannabis, any pre-conceived psychoeducation or stigma, and other nonpharmacologic techniques. Social work assessment may reveal concerns about prior experience, technological challenges, financial insecurity or inability, and physical limitations which may prohibit obtaining necessary paperwork or obtaining medical cannabis. Interventions may include psychoeducation, alongside other support staff, about medical cannabis recommendations, screening for financial assistance offered through the State, offering of referrals for application support, or mobilization of family support. Integral to the social work role is screening for which program will best suit patient needs. For example, patients who rely on caregivers to go to the dispensary to obtain medical cannabis will need to apply for the Compassionate Use of Medical Cannabis Pilot Program, which allows for a caregiver card.

The nursing assessment evaluates health literacy, indicated symptoms, and the ability to administer cannabis. Nurses should plan to discuss expectations for symptom management, side effects especially the concern for “feeling high,” and prepare the patient for trial and error while initiating cannabis use. Nurses should also be prepared to explain the pros and cons of routes of administration, different strains, and ratios of dosage with the main focus on THC:CBD. Older adults who are cannabis naïve often tolerate lower ratios of THC:CBD formulation better and should be started on very low doses 1-2.5mg. Finally, nurses should be equipped to review concerns specific to older adults including polypharmacy, contraindications for diseases such as cardiac and lung, memory, fine motor skills, and altered metabolism (Zipursky 2020; Yang, et al. 2021). Any of these concerns should be brought to the attention of the medical provider before the certification process moves forward.

Medical providers should have a longitudinal relationship with a patient before endorsing the use of medical cannabis for an older patient. It is our practice to offer FDA-approved medications such as dronabinol and nabilone for the management of pain, nausea, loss of appetite due to cancer prior to offering medical cannabis. If there is a history of substance use disorder that is not being treated, medical cannabis may not be the best option. If a patient has significant cognitive impairment, providers should recommend enlisting the support of a caregiver with the patient’s management of their use of medical cannabis. In many states, medical providers cannot specify what formulations a patient should use. For pain, for example, higher CBD:THC ratios are advised. Physicians should reiterate the advice to use low doses at initiation and to increase doses slowly (Yang, et al. 2021). We advise patients to select dispensaries that have patient counselors. Not all dispensaries have counselors and if they do there are no state-supported certification processes that we are aware of that standardize their competencies. There may be marked variability in formulations that are available at different dispensaries.

Ethical and Social Considerations

Complicating medical recommendations for medical cannabis are social and ethical considerations. For older adult patients living outside the home, such as in a nursing home or assisted living facility, rules and safety regulations of the individual facilities may inhibit use. For our patients who may still be employed, regardless of age, we generally recommend following guidelines for alcohol, specifically not consuming on-site or bringing on site. Illinois imposes some job restrictions, such as on CDL- driver’s license or a school bus driver permit.

Furthermore, a patient’s ability to physically get to a dispensary may limit our ability for certification options. In Illinois, the Compassionate Use of Medical Cannabis Pilot Program allows for a caregiver to apply for a card, which allows them to purchase a product on the patient’s behalf. Ethically, the consideration of equity and distributable justice abound. Health professionals may have concern about societal and systemic harms which may be a result of medical cannabis use (Gardiner, et al. 2019). In our practice we allow medical providers to opt-out of endorsing medical cannabis use for patients if they have an ethical objection to its use. Many medical providers will also be reluctant to endorse its use.

Special Concerns for Older Adults

Because older adults are more likely to be prescribed multiple medications, drug interactions may be of greater concern. For example, clarithromycin, erythromycin, cyclosporine, verapamil, itraconazole, voriconazole, and boceprevir would be expected to inhibit the metabolism of THC whereas rifampin would diminish the effect of both THC and CBD. CBD would accumulate in patients receiving ketoconazole and serious toxicity could occur with tacrolimus and case reports of reduced efficacy of the anticoagulant warfarin with medical cannabis use exist.

Because older adults often have limited incomes, medical cannabis may be cost prohibitive severely limiting their access to this modality.

Older adults may also face additional challenges in their use of medical cannabis such as reading the font of packaging labels to verify content and dosing instructions. There is also variability in dosing in different states and a lack of standardization by different dispensaries.

Older adults, especially cannabis naïve ones, can be at higher risk for inaccurate administration. Although younger adults may have used cannabis in edible forms, older adults are more likely to have the majority of their interactions from inhaled cannabis. As many providers are more comfortable encouraging oral cannabis, they likely will need additional education on its use (Inglet 2020). Because of the unfamiliarity, older adult patients have a higher risk of side effects. Changes in metabolism can also put them at greater risk.

Of particular concern in older adults would be the heightened risk of heart attacks due to smoking medical cannabis due to a higher likelihood of having coronary artery disease. It is the practice of the first author to discourage our patients from using inhaled formulations of medical cannabis as there is not a risk of heart attacks with edible or topical medical cannabis (Richards JR 2019).

Anecdotally, staff at dispensaries are less equipped to deal with the needs of older adults. For example, a  cancer patient who was recently seen in our clinic who had started medical cannabis called to say she was having trouble ”measuring” her edible. She was requested to bring in the cannabis edible and was found to have 100mg THC gummy bears. The staff had told her to break it into 10ths and she had tried to measure “each foot and paw” to estimate this.

In another case we encountered, an 81-year-old cancer patient called saying he did not want to use medical cannabis anymore because it made him “feel strange” and he “became the couch.” After further discussion, it was found that the patient, naïve to cannabis, had been given a 40mg edible by dispensary staff. The instructions were unclear for him and he took it all at once. After reviewing a more appropriate dosage the patient was interested in trying again with the understanding that a feeling of being high was a side effect but was unlikely to be as severe at lower doses.

Recommended starting doses would be much lower typically 1-2.5MG THC (Yang, et al. 2021). We also recommend that they increase doses slowly to reduce the likelihood of incurring side effects (Cox EJ 2019). Precise dosing is often limited by inaccurate labeling (Ekor 2014; Raynor et al. 2011). For example, among cannabis products purchased online, 26% contained less CBD than indicated on the label (Bonn-Miller et al. 2017).

These situations could be avoided in the future by making it more clear to patients that dispensary staff, while helpful, may not always be prepared to assist them in avoiding side effects. Older adults should also be prepared to discuss not wanting cannabis for the sensation of feeling high with staff. This is especially true for patients who are not certified for medical cannabis.

Patients with hesitancy to pursue formalized medical cannabis certification may benefit from the recommendation of recreational use. While this is not applicable in all states, recreational cannabis allows for introductory trials which avoid the time and cost of certification. Limitations to this recommendation include cost (recreational cannabis is taxed at a higher amount).

Final Thoughts

With the aging population, medical professionals have begun focusing more of their efforts into tailoring care for the needs of older adults. In order to best serve this population an interdisciplinary approach to care is especially important when implementing new treatments. As medical cannabis becomes more popular, medical teams should be prepared to discuss this option with their patients and to recognize special considerations. With new evidence coming out rapidly it is the responsibility of healthcare professionals to work together in creating an organized approach for assessment of need, appropriateness for safe use, and program options available for their older adult patients.