Differences Between Cancer Patients And Others Who Use Medicinal Cannabis

Differences between patients with cancer and those who do not have cancer who are seeking Cannabis are not well understood, but more information on the differences between these two groups is needed to support ongoing research efforts and policy decisions. Using a survey-based approach, we characterized groups of adults seeking medical Cannabis certification who did and did not have cancer. These data revealed that adults with cancer have multiple features that distinguish them from other adults seeking medical Cannabis certification. These differences fall into four main areas: (1) demographics, (2) symptoms and functioning, (3) Cannabis use characteristics (frequency/amount and mode of administration), and (4) certification-related differences. We will review each of these in the following paragraphs.

Several demographic differences were noted in this study. These included the finding that those with cancer were older than those without cancer, in agreement with prior findings from a single dispensary in New York [12]. Given that cancer diagnoses increase with age, this finding is not surprising. Additionally, those with cancer were less likely to be working and more likely to be classified as disabled. Both of these findings would be expected to be associated with both age. Potential symptoms from cancer diagnosis. We did not note differences in gender, race, or educational attainment between those with cancer and those without cancer, suggesting that the populations were relatively balanced in terms of these factors. Others have noted female predominance previously in those with cancer, though there is a general male predominance amongst those using Cannabis in the general population and in those with cancer [12-14]. Future studies should carefully consider age and employment status when seeking to understand Cannabis use in cancer patients given demographic differences observed in this study.

Symptom and functioning differences between those with cancer and those without cancer are considered together, as they are likely closely linked. In terms of symptoms, patients with cancer generally had similar physical function to those without cancer as assessed by PCS in setting of less severe pain. It is important to note that 92% of those without cancer were seeking Cannabis for pain (similar to previous reports), suggesting that the non-cancer population was enriched for those with severe pain [12]. This may explain why those with cancer had less pain than those without cancer. People with cancer also noted greater mental health-related disability as measured by MCS from the SF-12, a finding that is of particular concern given conflicting reports as to the impact of Cannabis on mood and mental health as well as a Canadian report that noted higher suicidal ideation among cancer patients using Cannabis [4, 14]. Others have suggested that Cannabis may benefit head and neck cancer patients through reduction in anxiety and pain and improved quality of life [15]. The mental health difficulties associated with cancer diagnosis and treatment are well known, and a better understanding of mental health implications of Cannabis use in this vulnerable population will be key as researchers seek to understand risk and benefits of Cannabis use in those with cancer [16, 17]. Individuals with cancer used Cannabis less frequently. In smaller amounts than those without cancer. Specifically, more than one fifth of those with cancer reported never/rarely using Cannabis. Given the prominent role that patients with cancer have played in policy discussions, it was expected that those with cancer would use Cannabis more frequently. A possible explanation for at least some of the lower observed usage rates in patients with cancer may be related to differences in certification rates. Those with cancer had lower certification rates, and cancer patients were less likely to endorse Cannabis use if they lacked certification. Taken together, lower prior certification rates and what appears to be better adherence to legal guidance suggests that policy and/or regulatory changes may differentially impact those with cancer relative to other medical Cannabis patients. Individuals with cancer were also older than others, and there are known to be age-related differences in Cannabis use that may relate to perceptions about Cannabis [18]. This could also potentially explain differences, though large scale data on Cannabis perception are limited in those with cancer.

Those with cancer had different route of administration preferences. Fewer cancer patients chose to smoke Cannabis. Additionally, there was a nearly significant increase in the use of edible preparations in those with cancer with a p-value of 0.052. Further characterization of these differences and what drives them will be important to better understand this population of patients using Cannabis and guide educational and supportive policies and practices. Given that there were no differences with regard to the proportion of individuals who discussed Cannabis use with their primary care provider, it seems less likely that primary care provider recommendations against smoking might have played a role, but it is important to note that some groups of providers have recommended against smoking Cannabis [19].

As noted above, there were no differences in the proportion of patients who told their doctor about their Cannabis use between those with cancer and those without cancer. Approximately half of individuals with cancer noted that they had spoken with their doctor. We have no evidence as to the amount of education that individuals might have received in setting of these conversations, but others have noted that little advice is given by providers when Cannabis use is revealed [20]. Available data suggest that much patient education on Cannabis comes from outside of the medical community [20].

There are a number of key weaknesses of this study that should be recognized. The small size of this study makes generalizations to larger populations of medical Cannabis users less reliable and likely obscures some additional potential differences. The finding of less pain in cancer patients and equivalent physical functioning could be the result of bias due to the location of recruitment at ambulatory dispensaries and the requirement that a participant have the ability to fill out a survey. Those with advanced, painful bony metastatic disease might be under-represented in this setting. With regard to use frequency data, there is confounding between medical Cannabis card possession (lower in those with cancer) and cancer diagnosis. This likely did not impact other analyses beyond the use frequency and amount analyses. We would note that the concept of a “high” related to Cannabis may mean different things to different groups of individuals that could impact interpretation given that these data were collected by self-report. We also did not capture Cannabis product potency, so it is not possible to draw conclusions with regard to concentration of particular active compounds in products utilized by different groups. Despite these limitations, these data provide valuable insight into a very poorly studied area.