The Changing Epidemiology of Lung Health: Opportunities for Research on Cannabis and HIV Disease (The ORCHID Study)

Project Summary / Abstract Consumption of cannabis products is increasing in the United States. The prevalence of past month use among adults has grown from 5.8% in 2007 to 11.5% in 2019. Causes of this increase include an evolving regulatory environment, product innovations by the cannabis industry, and cultural trends towards greater

permissiveness. The effect of exposure to cannabis products on lung health are not fully understood, so the public health impact of increased cannabis consumption cannot be fully appreciated. In a recent report, the National Academy of Science, Engineering, and Medicine highlighted the critical need for more research to

determine whether long term exposure to cannabis leads to chronic lung disease. The overall objective of this proposal is to examine the effects of cannabis exposure on lung health. This proposal leverages a longstanding, NHLBI-funded multi-center cohort of adults living with or at risk for HIV infection—the

MACS/WIHS Combined Cohort Study—in which the lifetime prevalence of cannabis exposure exceeds 70%. The specific aims of the proposal are to: (1) measure the association of self-reported cumulative exposure to cannabis with lung function in persons living with or without HIV; (2) measure the effect of biochemically-

verified cannabis exposure on the change in lung function in persons living with and without HIV; and (3) pilot a novel instrument for measuring exposure to different cannabis products among persons living with and without HIV. The objective and aims of this proposal are in line with the NHLBI’s Strategic Goal to “reduce human

disease” through “clinical investigations that advance the prediction, prevention, preemption, treatment, and cures of human [lung] diseases.” In particular, this proposal is responsive to Compelling Question 2.CQ.03, “What biomarkers of… environmental exposure are predictive of disease onset or progression?” and Critical

Challenge 3.CC.04, “Advances in methods and models for assessing and characterizing exposures are needed to understand differences in health among populations.” The benefits of the proposed research are expected to accrue broadly to the public health and welfare of current and future Americans. This K23 award

supports mentored career development for Richard Wang, MD MAS, Assistant Professor of Medicine at the University of California San Francisco (UCSF). Dr. Wang’s long-term career goal is to become an independent clinician investigator focused on improving the respiratory health of vulnerable populations, including persons

with HIV. His short-term goal is to better understand the risks to respiratory health posed by the rapidly changing prevalence and practices of cannabis consumption among the American public. This K23 award supports Dr. Wang to develop expertise in: statistical methods for causal inference from complex observational

data; the biochemical measurement of cannabis metabolites in biological samples; and the measurement of cannabis use with survey instruments. Dr. Wang benefits from a superb mentoring team with complementary scientific expertise and a vibrant scientific milieu at UCSF for rigorous multi-disciplinary research and training.