Over the past ten years, marijuana, or cannabis, use has changed drastically in the United States, says epidemiologist Denise C. Vidot, an assistant professor at SONHS and cannabis research expert. As states legalized cannabis, use increased, with the highest prevalence of use among 18 to 25 year olds. There are also new routes of administration, such as electronic vaporizing devices, or vapes. Significantly, she points out, evidence shows potency of THC (Δ9-tetrahydrocannabinol), the psychoactive component in cannabis, has risen from 3.7 to 30 percent.
But evidence-based research has not kept pace. That’s where Vidot is making a difference. This past July she received a four-year research project grant (R01) totaling $2,866,576 from the National Institutes of Health’s National Heart, Lung, and Blood Institute for her collaborative study, “The Effects of Cannabinoids and Route of Cannabis Administration on Subclinical Cardiovascular Disease Risk.” It is Vidot’s first major NIH award as principal investigator (PI).
“The impact of THC on cardiovascular disease (CVD) risk is unclear,” she says. “Studies suggest that THC may play a role in adverse cardiovascular health; however, the combined levels of THC and nonpsychoactive compounds within cannabis, such as cannabidiol (CBD), on CVD risk are understudied as well. Accumulating evidence suggests that CBD has anti-inflammatory and antioxidant properties that benefit the cardiovascular system.”
Vidot’s multidisciplinary team will examine the relationship between THC, CBD, and CVD among cannabis users ages 18 to 30.
Understanding this relationship is important because CVD, which encompasses a range of heart conditions, remains the leading cause of death in the U.S., killing someone ever y 37 seconds, according to the Centers for Disease Control and Prevention. Vidot’s long-range goal is to inform responsible cannabis use and identify levels of THC/CBD associated with dangerous cardiovascular outcomes for cannabis users at increased risk for heart disease.
The first step will be to compare subclinical CVD risk in cannabis users versus nonusers of cannabis and tobacco, as well as subclinical CVD risk based on the users’ most common route of administration for the cannabis: blunts (cannabis rolled into a tobacco leaf), joints (cannabis rolled in paper with no added tobacco), or vape. Blood and urine samples will be used to quantify THC/CBD levels. Several subclinical risk factors for CVD, such as waist circumference, blood pressure, and fasting lipid profile, will be measured at baseline and one year out.
This will be the first study to examine at multiple time points the impact of urine- and blood-quantified THC/CBD levels by route of administration on objective measures for subclinical CVD risk in this age group, notes Vidot. The study is also among the first to implement recommendations from the National Academies of Science Report on the Health Effects of Cannabis and Cannabinoids, which cites Vidot’s cannabis and metabolic syndrome research as one of two published studies in the literature.
“We hypothesize that there will be a differential effect of subclinical CVD risk by route of administration,” she says.
Vidot’s co-investigators are, from the University of Miami, cardiologist Claudia Martinez, psychologist Barry Hurwitz, forensic toxicologist Lisa Reidy, and biostatistician Kristopher Arheart, and, from Florida International University, substance use psychologist Raul Gonzalez.
Research reported in this publication was supported by the National Heart, Lung, And Blood Institute of the National Institutes of Health under Award Number R01HL153467. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
