Cannabis use among adults undergoing cancer treatment

Background: Little is known about the risks and benefits of cannabis use in the context of cancer care. This study characterized the prevalence, reasons for use, and perceived benefits of cannabis and compared symptoms and perceived risks between those who reported past 30-day cannabis use and those who did not.

Methods: Adults undergoing cancer treatment at a National Cancer Institute-designated cancer center completed measures of sociodemographic characteristics, cannabis use, use modalities, reasons for use, perceived harms/benefits of use, physical and psychological symptoms, and other substance/medication use. Analyses compared patients who used or did not use cannabis in the past 30 days.

Results: Participants (N = 267) were 58 years old on average, primarily female (70%), and predominantly White (88%). Over a quarter of respondents (26%) reported past 30-day cannabis use, and among those, 4.5% screened positive for cannabis use disorder. Participants who used cannabis most often used edibles (65%) or smoked cannabis (51%), and they were younger and more likely to be male, Black, and disabled, and to have lower income and Medicaid insurance than participants who did not use cannabis. Those who used cannabis reported more severe symptoms and perceived cannabis as less harmful than those who did not use cannabis. The most common medical reasons for cannabis use were pain, cancer, sleep problems, anxiety, nausea/vomiting, and poor appetite. Participants reported the greatest cannabis-related symptom relief from sleep problems, nausea/vomiting, headaches, pain, muscle spasms, and anxiety.

Conclusions: Patients with cancer who used cannabis perceived benefits for many symptoms, although they showed worse overall symptomatology.

Plain language summary: Among adults undergoing cancer treatment, 26% reported cannabis use in the past 30 days. Those who used cannabis were more likely to be male and disabled and to have lower income and Medicaid insurance than those who did not use cannabis. Participants most commonly reported using cannabis for pain, cancer, sleep, anxiety, and nausea/vomiting and reported the greatest perceived benefits for sleep, nausea/vomiting, headaches, pain, muscle spasms, and anxiety, yet participants who used cannabis also reported feeling worse physically and psychologically compared to those who did not use cannabis. Participants who used cannabis were more likely to report that cannabis was less risky to their health than alcohol, smoking, and opioids than those who did not use cannabis.