Abstract
Classic psychedelics and cannabis are at the forefront of emerging alternative therapies to mitigate cancer symptoms and comorbidities, yet their prevalence, patterns, and long-term effects among older adults remain unclear. This dissertation utilizes 2015–2022 National Survey on Drug Use and Health data to 1) examine trends in lifetime cannabis and psychedelic use among US adults aged ≥50 years, 2) assess variations by cancer history and type, and 3) investigate potential associations with prostate cancer.
The first study estimates prevalence and trends in classic psychedelic, cannabis, and combined use (co-use) among adults with past, recent, or no cancer history, considering socio-demographics. Findings show increasing use, particularly among adults ≥65 and males, highlighting the need for further research into therapeutic intent, usage patterns, and integration into cancer care. The second study examines the prevalence of cannabis, classic psychedelic, and co-use among cancer patients by cancer type. Findings show similar cannabis use in cancer survivors (41.6%) and non-cancer individuals (42.6%, p=0.21), but lower psychedelic (11.6% vs. 12.9%, p<0.01) and co-use (11.2% vs. 12.6%, p<0.01) in survivors. Usage varied by cancer type, with the highest co-use among head and neck, cervical, and hepatobiliary/pancreatic cancer survivors. Findings underscore the need for further research into motivations, risks, and therapeutic potential in survivorship care. The third study tests the association between co-use and a diagnosis of prostate cancer. Among those ≥65 years, classic psychedelic-only use was associated with more than three-fold higher odds of prostate cancer vs non-users (AOR: 3.60, 95% CI: 1.71–7.55, p<0.01). Classic psychedelic-only users also had higher odds of prostate cancer vs co-users (AOR: 4.58, 95% CI: 1.89–11.1, p<0.01).
This dissertation is the first in the literature to report rising cannabis and psychedelic use among a population-based sample of older US cancer patients, highlighting type-specific trends and links to prostate cancer.