Marijuana-related car crashes, preterm births, and accidental ingestion by kids on rise since legalization in Illinois, study shows

Marijuana legalization in Illinois has come with increased pot-involved deadly crashes, a rise in accidental ingestion among children, an association with psychotic disorders, and increases in preterm births by mothers using cannabis, a new study has found.

Reported benefits include decreases in marijuana-related arrests and in opioid and benzodiazepine-related fatalities.

Contrary to fears, there appears to be little to no increase so far in cannabis use among minors.

The findings come from the state’s annual cannabis report for 2023, conducted for the state by the University of Illinois at Chicago Jane Addams College of Social Work.

The rate of fatal crash drivers who tested positive for marijuana rose from 25% in the two years before legalization to 37% in 2020, the first year of legal recreational sales in Illinois.

Michigan, the other Midwestern state to legalize general adult use at about the same time, saw a similar increase, while other neighboring states remained below 24%. The fatal crash rate for weed in Illinois exceeded that for alcohol, which remained at about 35%.

Drivers under 45 were much more likely to test positive in fatal crashes, while drivers who’d taken other drugs were also significantly more likely to be involved in a deadly crash.

The rate of self-reported driving under the influence of cannabis also doubled to 5.4% for those 26 and older between 2018-19 and 2019-20.

As the Tribune previously reported, the number of calls to the Illinois Poison Control Center for nonfatal marijuana overdoses by children 17 and under also rose dramatically since legalization, from fewer than 100 in 2016 to about 500 in each of the past two years. Calls about children typically were caused by kids eating their parents’ gummies. Adults saw a doubling of overdose calls in that time.

About 20% of persons using cannabis in the past year said they experienced one or more adverse effects, most commonly with panic reactions, feeling faint or dizzy, and nausea or vomiting.

The rate of cannabis use disorder for Illinois residents 12 and older was estimated to have risen to 2.6% in 2019-20, from 2% in 2018-19. As with some other measurements, researchers said, it’s unclear how much of that may have been attributable to the COVID-19 pandemic, a period that also showed increases in alcohol use disorder in the Midwest.

The head of the research effort, James A. Swartz, professor and interim associate dean for research at the school, said those results were concerning, but otherwise, some of the fears about marijuana legalization had so far not panned out.

“Tentatively, I think the state is doing a reasonable job,” he said.

Most noticeably, data have not shown an increase in use among children in Illinois.

First use among those 12 to 17 increased from 2015 to 2018, but decreased through 2021, with no increase in frequent use in that age group.

However, Illinois and Michigan both had higher rates of past-month use across all age groups, particularly young adults.

Frequent cannabis use, 20 days or more a month, increased from 4.8% to 6.4% in Illinois, with a tripling to 11% among Blacks in 2020. There was a similar overall increase in Michigan, while neighboring states again saw no change.

Of particular concern was that between 2017 to 2020, there was a 6% increase in past-month cannabis use among pregnant women. Medical experts warn against using marijuana during pregnancy, because it can harm the baby.

People with a serious mental illness and people in poverty also had much higher rates of both any and frequent cannabis use.

Among medical users, chronic pain was the most commonly cited reason for use. But 86% of medical users, and almost two-thirds of recreational users, had used it to manage mental health symptoms such as anxiety, depression, and PTSD/trauma.

One area researchers would like to delve into more is the effect of high-potency marijuana, with concentrates now reaching more than 80% THC, the main component that gets users high.

People hospitalized for cannabis use disorder had a higher prevalence of manic episodes or psychotic disorders. Studies elsewhere have shown a strong association between frequent use and high-potency pot and psychosis, including schizophrenia.

Swartz would also like to research to what extent the use of cannabis may decrease the use of opioids. But state regulators so far have not given him access to data from the state’s program that uses cannabis as an alternative to opioids, citing privacy concerns.

Swartz noted that cannabis taxes in Illinois remain high, and retail stores remain scarce in Black neighborhoods on the South and West sides of Chicago, which discourages people from the legal market.

As more stores opened and use became more common, the percentage of cannabis bought legally in Illinois more than doubled from 2018-19 to 2021, to 59%. The most common reason cited for buying illicit pot was the high cost of the legal market.

The report also cited a small increase in cannabis poisoning as a contributing cause of death in Illinois, to 27 fatalities in 2022.

Meanwhile, the number of cannabis arrests in the state continued to plummet, from more than 45,000 in 2015 to less than 3,000 in 2021.

Many of the statistics came from the National Survey on Drug Use and Health. The report was submitted to the Illinois Adult Use Cannabis Health Advisory Committee, which may use the information to make recommendations to the Department of Human Services about public health awareness campaigns.