Tag: cannabis use

Prenatal Cannabis Exposure Impacts Persist to Pre-adolescence

Children
Photo by Ben Wicks on Unsplash

Children who were exposed to cannabis in the womb continue to show elevated rates of symptoms of psychopathology (depression, anxiety and other psychiatric conditions), even as they reach pre-adolescence (aged 11–12), according to research published in JAMA Pediatrics.

The study, led by Ryan Bogdan, associate professor at Washington University in St. Louis, is a follow-up to 2020 research from the Bogdan lab that revealed younger children who had been prenatally exposed to cannabis were slightly more likely to have had, inter alia, sleep problems, lower birth weight and lower cognitive performance.

In both cases, the effect is strongest when looking at exposure to cannabis after the pregnancy is known. To find out whether or not these associations persisted as the children aged, David Baranger, a postdoctoral researcher in the BRAIN Lab, revisited the more than 10 500 children from the 2020 analysis, who were an averaged of 10 years old in 2020.

The data on the children and their mothers came from the Adolescent Brain and Cognitive Development Study (ABCD Study), an ongoing study of nearly 12 000 children, beginning in 2016 when they were 9–10 years old, and their parents or caregivers.

This seemingly small change in age – from 10 to 12 – is an important one. “During the first wave, they were just children. Now they’re edging up on adolescence,” Baranger said. “We know this is a period when a large proportion of mental health diagnoses occur.”

An analysis of the more recent data showed no significant changes in the rate of psychiatric conditions as the children aged; they remain at greater risk for clinical psychiatric disorders and problematic substance use as they enter the later adolescent years.

“Once they hit 14 or 15, we’re expecting to see further increases in mental health disorders or other psychiatric conditions – increases that will continue into the kids’ early 20s,” Baranger said.

Source: University of Washington in St. Louis

Many Medical Cannabis Users also Use Nicotine

Photo by RODNAE Productions from Pexels

Users of medical cannabis are more likely to also use nicotine products than the general population, according to a Rutgers University study published in the American Journal on Addictions.

“Simultaneous use of cannabis and nicotine is a growing concern, but while the relationship between recreational cannabis and nicotine use is well-established, little is known about nicotine use among users of medical cannabis,” said Mary Bridgeman, a clinical professor at Rutgers Ernest Mario School of Pharmacy.

The researchers surveyed 697 patients aged 18–89 at a medical marijuana dispensary on their nicotine and cannabis use, how they self-administered the cannabis (smoked, vaped) and the medical conditions that qualified them for using therapeutic cannabis.

Nearly 40% of medical marijuana users reported using nicotine – sharply higher than the 14% of US adults who smoke.

Therapeutic cannabis users who also used electronic cigarettes or didn’t use nicotine at all were about four times more likely to vape, rather than smoke, cannabis than those who exclusively smoked cigarettes.

The study also found 75% of the respondents smoked cannabis rather than vaped and about 80% of the cigarette smokers reported planning to quit in the next six months.

“These findings reveal that while medical cannabis dispensaries may recommend vaping rather than smoking cannabis due to the health concerns associated with combustible products, this recommendation alone may not influence patients who also smoke cigarettes,” said Professor Marc Steinberg, co-author of the study.

“Between the higher rates of nicotine use in those using medical cannabis, the fact that cigarette smokers opt to smoke cannabis as well and that those people also are seeking to quit using nicotine presents a strong argument that dispensaries provide tobacco control messaging at the point-of-sale to encourage cigarette smokers to quit,” Prof Steinberg added. “The strategy also could increase the chances that a medical cannabis user would vape the product, which is a less harmful route than smoking.”

Source: Rutgers University

Spike in Traffic Crashes and Fatalities from Marijuana Legalisation

Photo by Kindel Media on Pexels

US States that legalised recreational marijuana saw a subsequent increase in traffic crashes and fatalities, researchers reported in the Journal of Studies on Alcohol and Drugs.

“The legalisation of marijuana doesn’t come without cost,” stated lead researcher Charles M. Farmer, PhD, of the Insurance Institute for Highway Safety.

Dr Farmer and colleagues’ analysis of five states that allow the recreational use of marijuana for adults age 21 and older revealed a 5.8% increase in the rate of traffic crash injuries and a 4.1% increase in fatal crash rates after legalisation and the onset of retail sales. At the same time, there was no increase in a comparison group of states which did not legalise marijuana.

The injury crash rate jumped after legalisation but before retail sales began. Traffic crash injuries rose 6.5% after legalisation but decreased slightly (-0.7%) after retail sales commenced. However, fatal crash rates increased both after legalisation (+2.3%) and after retail sales were authorised (+1.8%).

“Legalisation removes the stigma of marijuana use, while the onset of retail sales merely increases access,” explained Dr Farmer. “But access to marijuana isn’t difficult, even in places without retail sales. Users who previously avoided driving high may feel that it’s okay after legalisation.”

Marijuana legalisation’s stronger relationship with traffic crash injuries, rather than fatalities, may be due to how some drivers compensate when impaired by marijuana. Often, drivers under the influence of marijuana slow down and maintain a larger distance between themselves and other vehicles. A crash may be harder to avoid while impaired, but the lower-speed crashes that occur may be less likely to be fatal.

The authors note that earlier studies involving driving simulators have shown marijuana use to affect reaction time, road tracking, lane keeping and attention. However, Farmer notes that the current study is correlational, and increased marijuana use itself is likely not the sole cause of the increases seen.

“Studies looking for a direct causal link between marijuana use and crash risk have been inconclusive,” he says. “Unlike alcohol, there is no good objective measure of just how impaired a marijuana user has become. Until we can accurately measure marijuana impairment, we won’t be able to link it to crash risk.”

The researchers collected data on traffic crashes and traffic volume for 2009–2019 from 11 states and from the Federal Highway Administration. During the study period, five states had legalised recreational marijuana while a comparison group of six states did not. The authors statistically adjusted for factors known to contribute to crashes and fatalities, including seat belt use and unemployment rate.

In the states that legalised cannabis, changes in injury crash rates varied: Colorado had the biggest jump (+17.8%) and California the smallest (+5.7%) after both legalisation and the onset of retail sales. Nevada’s rate decreased (-6.7%). For fatal crashes, increases occurred in Colorado (+1.4%) and Oregon (3.8%), but decreases were found in Washington (-1.9%), California (-7.6%) and Nevada (-9.8%).

Farmer points out that states considering marijuana legalisation should consider a few steps to help forestall a potential increase in crashes. “First, convince everyone that driving under the influence of marijuana is not okay,” he says. “Then, enact laws and sanctions penalising those who ignore the message. Finally, make sure you have the resources (ie, staffing and training) to enforce these laws and sanctions.”

Source: EurekAlert!

A Brain ‘Breathalyser’ for THC Intoxication

Image by Falkurian Design on Unsplash

Scientists have developed a noninvasive brain imaging procedure to identify individuals whose performance has been impaired by THC, the psychoactive ingredient of cannabis. As reported in Neuropsychopharmacology, the technique uses functional near-infrared spectroscopy (fNIRS) to measure brain activation patterns linked to THC intoxication. The technology could have a great impact on road and workplace safety. 

The increasing legalisation of cannabis has driven the need for a portable brain imaging procedure that can distinguish between THC-caused impairment and mild intoxication. “Our research represents a novel direction for impairment testing in the field,” explained lead author Jodi Gilman, PhD. “Our goal was to determine if cannabis impairment could be detected from activity of the brain on an individual level. This is a critical issue because a ‘breathalyser’ type of approach will not work for detecting cannabis impairment, which makes it very difficult to objectively assess impairment from THC during a traffic stop.”

In previous studies, THC has been shown to impair cognitive and psychomotor performance essential to safe driving, a factor thought to at least double the risk of fatal motor vehicle accidents. However, concentration of THC in the body does not correspond well to functional impairment. Regular cannabis users often can have high levels of THC in the body and not be impaired. Metabolites of THC can remain in the bloodstream for weeks after the last cannabis use, well beyond the period of intoxication. Thus, there is a need for a different method to determine impairment from cannabis intoxication.

In the study, 169 cannabis users underwent fNIRS brain imaging before and after receiving either oral THC or a placebo. Participants who reported intoxication after being given oral THC showed an increased oxygenated haemoglobin concentration (HbO) – a type of neural activity signature from the prefrontal cortex region of the brain – compared to those who reported low or no intoxication.

“Identification of acute impairment from THC intoxication through portable brain imaging could be a vital tool in the hands of police officers in the field,” said senior author and principal investigator A. Eden Evins, MD, MPH, founding director of the Center for Addiction Medicine. “The accuracy of this method was confirmed by the fact impairment determined by machine learning models using only information from fNIRS matched self-report and clinical assessment of impairment 76% of the time.”

The study suggested the feasibility of inexpensive, lightweight, battery-powered fNIRS devices that could be incorporated into a headband or cap, and thus require minimal set-up time.

“Companies are developing breathalyser devices that only measure exposure to cannabis but not impairment from cannabis,” said Dr Gilman. “We need a method that won’t penalise medical marijuana users or others with insufficient amounts of cannabis in their system to impair their performance. While it requires further study, we believe brain-based testing could provide an objective, practical and much needed solution.”

Source: Massachusetts General Hospital