The role of cancer in marijuana and prescription opioid use in the United States: A population-based analysis from 2005 to 2014.

This population-based analysis revealed a considerable proportion of respondents with cancer self-reporting marijuana use (40.3%) and a significantly higher prevalence of opioid use among respondents with cancer. In the midst of an opioid epidemic, an evolving political landscape, and new developments in oncology, quantifying the prevalence of opioid and marijuana use in the US population, especially among patients with cancer, is particularly relevant. Although opioid use did not significantly change from 2005 to 2014 among all respondents, marijuana use did increase, likely reflecting increased availability and legislative changes. A cancer diagnosis did not significantly affect longitudinal opioid or marijuana use.