Last week, U.S. Senators John Cornyn and Dianne Feinstein co-chaired a hearing at the Senate Caucus on International Narcotics Control to examine public health questions and issues surrounding cannabis (or as they referred to it, marijuana).
The hearing, titled: “Marijuana and America’s Health: Questions and Issues for Policymakers,” was aimed at providing an opportunity to understand what scientific research has yielded regarding cannabis’ efficacy as a medical treatment, its effect on motor skills and driving impairment, its health impacts on adolescent use and other pertinent questions and concerns.
The hearing consisted of two panels. The first featured Dr. Jerome Adams, surgeon general of the United States, and Dr. Nora Volkow, director of the National Institute of Drug Abuse. They both offered their expertise and insight into cannabis use in America, and its potential health concerns.
The second panel featured a series of PhDs from top-ranking universities, all of whom spoke on cannabis, and its effects on human health based on recently published studies they helped produce.
During the two-hour hearing, many issues were addressed. However, since so much is still unknown about the effects of cannabis on public health, some clear themes emerged. Here are four of the biggest takeaways from the hearing:
1 | Cannabis’ Schedule I Status Impedes Research
Over the course of the hearing, the impediments to cannabis research due to its classification as a Schedule I Drug was brought up by nearly every panelist.
Dr. Volkow was one of many who criticized the fact that there is currently only one legal source in the U.S. for scientists to obtain cannabis to use in studies, saying that “the process is very slow” to get marijuana from the facility, which is at the University of Mississippi. “DEA registration can take, if you’re lucky, one year to obtain,” Volkow said. “That delays the process enormously.”
Robert Fitzgerald, Ph.D., Professor of Pathology from the University of California-San Diego, concluded his statements by recognizing that, “Due to federal regulations, the government cannot study products the population is exposed to. We have unleashed an uncontrolled experiment on our entire population with limited ability to study it. Without good data, it is hard to develop good policy.”
“We have unleashed an uncontrolled experiment on our entire population with limited ability to study it.”
Staci Gruber, Ph.D., Associate Professor of Psychiatry from Harvard Medical School, echoed the concerns of her fellow panelists, stating, “The Schedule I status of marijuana leads to a number of obstacles in conducting research. Policy, at this point, has clearly outpaced science and as the nation has warmed to both the use of medical and recreational marijuana the need for empirically sound data is critical to maximize benefit and reduce harm.”
Fortunately, both Senators Cornyn and Feinstein are aware of these bureaucratic impediments to research. “Much of what we know about marijuana is anecdotal [which is] due in part to the fact that marijuana’s status as a Schedule I drug makes it difficult to research,” Senator Feinstein stated.
Sen. Cornyn suggested that he’s open to working with Sen. Feinstein on across-the-aisle legislation.
2 | The relationship between driving impairment and THC is more complex than with alcohol.
While the relationship between THC and driving impairment is far more complex than with alcohol, the experts agree that THC impairs driving ability.
Dr. Fitzgerald, a clinical toxicologist at UC San Diego, is part of a team of investigators at UC San Diego center for cannabis research, focused on understanding both beneficial and detrimental effects of cannabis on human health. They recently finished one of the largest studies to date on the effects of smoking cannabis on driving performance.
“With ethanol, there is a clear relationship between the amount consumed, the blood concentrations and effect on driving. The relationship between blood concentration of THC and crash risk has not yet been established,” Fitzgerald stated. “However, there is a clear identification that THC impairs driving performance. The question that still remains is how best to identify drivers who are impaired by marijuana. There are no clear solutions and legislative directives must balance keeping our roads safe with due process,” he informed the Caucus.
The poor relationship between concentration of THC and levels of impairment have already been documented, but due to rapid changes in blood THC concentrations over time, there is no minimum safe threshold through which a driver can be considered to have been unaffected while driving following recent cannabis use. Consequently, there is no scientific basis for THC limits for driving. Still, 18 states have per se statutes. In California, law is based on officer observations plus toxicology findings. “This law will likely continue for the foreseeable future,” he believes.
3 | Concerns over adolescent use and use amongst pregnant women were unanimous
“When it comes to cannabis, there is no one size fits all,” said Dr. Gruber when discussing the challenges researchers face when studying the effects — both positive and negative — of cannabis on human health. However, one thing seemed clear and consistent amongst all panelists: cannabis use poses possible risks and dangers to both adolescents and pregnant women.
Adolescent Use
On August 29, 2019, the Surgeon General’s Advisory on Marijuana Use and the Developing Brain was issued to emphasize the importance of protecting our nation from the health risks of marijuana use in adolescence and during pregnancy.
According to the report, “The human brain continues to develop from before birth into the mid-20s and is vulnerable to the effects of addictive substances. Frequent marijuana use during adolescence is associated with structural and functional changes in areas of the brain involved in attention, memory, decision-making, and motivation, and in deficits in attention and memory. Marijuana can also impair learning in adolescents. Chronic use is linked to declines in IQ and school performance, which may jeopardize professional and social achievements, and life satisfaction. Regular use of marijuana in adolescence is linked to increased rates of school absence and drop-out, as well as suicide attempts.”
Marijuana Use during Pregnancy
A national survey co-authored by Dr. Volkow found, “Marijuana use in the past month among pregnant women doubled (3.4 percent to 7 percent) between 2002 and 2017.
This is particularly alarming as studies have shown that marijuana use in pregnancy is associated with adverse outcomes, including lower birth weight and preterm delivery. For example, The Colorado Pregnancy Risk Assessment Monitoring System reported that maternal marijuana use was associated with a 50 percent increased risk of low birth weight regardless of maternal age, race, ethnicity, education, and tobacco use.
4 | Dr. Sean Hennessy’s 6-4-4 effectively summarized the hearing
Dr. Sean Hennessy, a pharmacist and epidemiologist at the University of Pennsylvania, is a member of a 16-person committee which published a 468 page book titled The Health Effects of Cannabis and Cannabinoids, released by the National Academy of Science, Engineering and Medicine in 2016.
The report is a comprehensive synthesis of the existing literature about the potential health effects, both therapeutic and harmful, of cannabis and cannabis-derived products. He broke down the book into the following categories: 6 health effects with high-level evidence; 4 challenges to conducting research on health impacts of cannabis; and 4 recommendations for moving forward. Overall, it was a decent microcosm of the entire panel, with some of the key points being:
- Cannabis use prior to driving appears to increase the risk of motor vehicle crashes.
- In states where cannabis is legal, there is an increased risk in unintentional cannabis overdose for children.
- Pregnant women who consume cannabis increase the risk their baby will be born with lower birth weight.
- Initiating cannabis use at a younger age increases chances of problematic cannabis use later in life.
- Cannabis-based products can relieve the symptoms of people with multiple sclerosis can obtain relief from their symptoms using cannabis-based products.
- Schedule I classification creates barriers that impede research.
- It is difficult for researchers to gain access to quantity, quality, and types of cannabis products that they need to conduct research.
- It is difficult to obtain funding to support cannabis research and improvement and standardization of research methods are needed.
