Teen asthma may be rising in states with legalized recreational cannabis use

The prevalence of asthma rose slightly among teens and youth from some race/ethnicity groups in states with recreational cannabis laws compared with states where cannabis is illegal, according to a study published in Preventive Medicine.

“Many people mistakenly assume that cannabis use and cannabis smoke is ‘harmless’ in terms of secondhand smoke, which is understandable as there has been no public education on secondhand cannabis smoke, which is in stark contrast to the decades of educational campaigns informing the public of the potential harms of secondhand cigarette smoke, especially for children,” Renee D. Goodwin, PhD, MPH, clinical psychologist, adjunct associate professor in the department of epidemiology at Columbia Mailman School of Public Health and professor of epidemiology at The City University of New York, told Healio. “The industry’s presentation and the legalization by state government communicates to folks that ‘this must be completely safe.’ In the process of focusing on adult use without penalty (which is entirely possible without full commercialization), it seems that several key clinical and public health issues have been neglected.

“Hopefully it will not take 1 to 2 decades to put similar protections in place regarding exposure to secondhand cannabis smoke and provide education so that any impact of increased adults use on the health of children can be mitigated,” she added.

In an ecologic analysis, Goodwin and colleagues evaluated 2011 to 2019 data from the U.S. National Survey on Children’s Health of 227,451 children (mean age, 8.56 years; 50.9% boys; 59.6% non-Hispanic white; 16.7% Hispanic; 12.3% Black; 11.3% other) aged 0 to 17 years to determine the association between legalization of cannabis and the prevalence of pediatric asthma within states using difference-in-difference (DID) analyses.

Researchers considered whether states had medical cannabis laws (MCL) and/or recreational cannabis laws (RCL). RCL states included those with both MCL and RCL adopted between 2011 and 2018, whereas MCL states had these laws alone, either adopted before 2011 (“established MCL states”) or between 2011 and 2018 (“recent MCL states”).

Results

Overall, from 2011-2012 to 2018-2019, researchers found a 1.1% statistically significant decrease in the occurrence of asthma in children.

Further analysis adjusted for age, gender, race/ethnicity, poverty level and insurance coverage showed larger declines in asthma compared with 2011-2012 rates in states without cannabis legalization (2016-2017, –1.14; 2018- 2019, –1.55) or states with recent MCL (2016-2017, –1.07; 2018-2019, –1.41), with slight, insignificant decreases in states with RCL or established MCL. Overall, researchers noted the rate of reductions did not differ statistically according to RCL/MCL status.

When evaluating trends by age, researchers observed that RCL states had a greater prevalence of asthma among adolescents aged 12 to 17 years in 2018-2019 relative to 2011-2012 (DID estimate = 2.56; P = .028) than states where cannabis is illegal.

“We were initially surprised that the increase was more prominent among 12- to 17-year-olds, as we had hypothesized that younger children would be increasingly exposed to secondhand cannabis smoke which could provoke or exacerbate asthma and/or lead to poorly controlled asthma,” Goodwin told Healio. “Yet, given the timing of the study, and the fact that a) asthma is not generally diagnosed until earliest age 4 to 5 years (vs. wheeze at younger ages); b) with the timing of this study in terms of dates of legalization and lag time to follow-up, it is conceivable that the increase in 12- to 17-year-olds is a result of increased earlier exposure in legal states or it may be that this increase is due to cannabis use among 12- to 17-year-olds themselves.”

Also, children who belonged to other non-Hispanic historically underrepresented race and ethnicity groups in states with RCL and established MCL had larger increases in pediatric asthma prevalence (2016-2017 DID = 3.88; P = .013; 2018-2019 DID = 4.45; P = .004) relative to 2011-2012 rates, compared with states where cannabis is illegal.

Researchers found no significant differences in the rate of reduction in asthma prevalence between different categories of legalization when evaluating gender alone.

Future studies, recommendations

Goodwin and colleagues are planning to test whether public education can mitigate potential exposures, among other analyses.

“In our future studies, we are planning to take a more microlevel approach (vs. a national/state-level approach) to determine whether and how youth are exposed to cannabis smoke and the impact that cannabis commercialization and marketing cannabis as a medical treatment and wellness product with no potential harms associated with frequent use has on youth exposure,” Goodwin told Healio.

All clinicians must be prepared to discuss cannabis use, Goodwin added.

“First, clinicians in all specialties where guardians/caretakers/parents who take care of and reside with children need evidence-based guidelines on how to talk with parents about cannabis use and the potential impact of exposure to secondhand (and firsthand) cannabis smoke on youth respiratory health, especially among those with asthma,” she said. “That would include family physicians, pediatricians, pediatric pulmonologists as well as professionals who care for adults who are parents/caregivers. For instance, annual medical check-up exams should include screening questions on tobacco and alcohol use, which are used as prompts for further discussion and potential treatment. Cannabis use is not screened for and most health professionals are not trained to discuss these issues and advise parents.”

For more information:

Renee D. Goodwin, PhD, MPH, can be reached at rdg66@cumc.columbia.edu.

Reference:

• Asthma is on the rise among teens in states where cannabis is recreationally legal. https://www.publichealth.columbia.edu/public-health-now/news/asthma-rise-among-teens-states-where-cannabis-recreationally-legal#:~:text=Increases%20in%20asthma%20prevalence%20were%20found%20among%20teens,Health%20and%20The%20City%20University%20of%20New%20York. Published Jan. 12, 2023. Accessed Jan. 12, 2023.