Asthma prevalence increases with cannabis use among adolescents

Key takeaways:

• 29.56% of adolescents who used cannabis in the past 30 days and 23.02% of those who did not reported lifetime asthma.
• Cannabis use increased with age from ninth through 12th grade.

Asthma was more prevalent among adolescents who used cannabis in the previous 30 days compared with those who had not used it, according to a study published in Pediatric Pulmonology.

This prevalence also increased with greater cannabis use, although a definitive dose-response relationship could not be determined, Renee D. Goodwin, PhD, MPH, associate professor, department of epidemiology and biostatistics, Graduate School of Public Health and Health Policy, City University of New York, and colleagues wrote.

“Our studies have shown that cannabis use is increasing among adolescents across the country, and not limited to states with recreational cannabis legalization or where cannabis sales are completely commercialized,” Goodwin told Healio.

Renee D. Goodwin

Also, Goodwin, who is director of the substance, addiction and epidemiology unit and an adjunct faculty member at Mailman School of Public Health at Columbia University as well, noted that unlicensed cannabis shops in New York City sell to underage customers and violate numerous laws, but they remain open, ubiquitous and growing.

“Given the increase in ambient cannabis smoke in the air, and reports from school personnel, parents and youth themselves, as well as the fact that youth are the most vulnerable to adverse respiratory exposures since their bodies are still developing, we thought this was a critical population to focus on in terms of cannabis use among teens with asthma,” she continued.

Research also shows that prolonged cannabis use is associated with airway narrowing, Goodwin added.

“So, youth with asthma appear particularly at risk,” she said.

Study design, results

The researchers examined 2019 data from the Youth Risk Behavior Surveillance System (YRBSS), including records from 130,136 students in grades nine through 12 in 35 states. Questions in the YRBSS included:

1. Has a doctor or nurse ever told you that you have asthma?
2. During the past 30 days, how many times did you use marijuana?
3. During the past 30 days, on how many days did you smoke cigarettes?

The cohort was 49.61% female, but there were no significant differences between the sexes in their past 30-day cannabis use, the researchers said.

Also, the cohort was 52.44% non-Hispanic white, 16.11% non-Hispanic Black, 22.73% Hispanic and 8.72% additional race or ethnicity, with greater proportions of non-Hispanic Black and Hispanic respondents among the past 30-day cannabis group compared with the group that had no past 30-day cannabis use (P < .0001).

By grade, past 30-day cannabis use included 19.46% for ninth graders, 23.53% for 10th graders, 26.65% for 11th graders and 30.36% for 12th graders (P < .0001).

Adolescents who reported past 30-day cannabis use also reported more past 30-day cigarette use than those who did not report any past 30-day cannabis use (17.45% vs. 2.54%; P < .0001).

“Asthma was more common among youth who use cannabis, relative to those who do not, and the prevalence of asthma increases with frequency of use among ninth through 12th graders in the U.S.,” Goodwin said.

The adolescents who reported past 30-day cannabis use reported more lifetime asthma than those with no past 30-day cannabis use as well (29.56% vs. 23.02%; P < .0001), with 1.25 times the odds for lifetime asthma after adjustments for race and ethnicity, sex, grade and cigarette use.

Asthma prevalence generally increased with frequency of cannabis use in the past 30 days:

1. no use: 23.62% (adjusted OR = 1);
2. one or two uses: 27.99% (aOR = 1.22; 95% CI, 1.15-1.29);
3. three to nine uses: 28.72% (aOR = 1.25; 95% CI, 1.15-1.36);
4. 10 to 19 uses: 30.26% (aOR = 1.28; 95% CI, 1.16-1.41);
5. 20 to 39 uses: 28.34% (aOR = 1.2 (95% CI, 1.08-1.33); and
6. 40 or more uses: 31.38% (aOR = 1.35; 95% CI, 1.25-1.45).

“One-third (over 30%) of youth who reported using cannabis 40 or more times in the past month had asthma,” Goodwin said. “That is a striking percentage and potentially hidden public health issue emerging in plain sight.”

Despite these increases in asthma prevalence with frequency, the researchers said, they could not identify a definitive dose-response relationship based on YRBSS frequency categories.

Preventive measures

Educational efforts focused on the hazards of cigarette smoking have targeted adolescents in general as well as adolescents with asthma in particular, the researchers noted, yet cannabis use has increased among young people.

As a result, the researchers called for evidence-based approaches to inform public health professionals and clinicians alike about associations between cannabis use and asthma in adolescence so they can educate patients and the public.

Physicians can play a role in curbing cannabis use among adolescents as well, Goodwin added, although it might not be easy.

“Screen patients for cannabis use just as you do for tobacco use,” she said. “Many may not be forthcoming. Let them know of the latest evidence that cannabis appears to be associated with prolonged or exacerbated asthma. They are unlikely to know anything about this.”

Goodwin also said there was an urgent need for more research on the short-term and long-term effects of cannabis on physical and mental health.

“As of now, the only information the public receives is advertising by cannabis companies and encouragement to use cannabis from several state governments, eg, New York,” she said.

None of this information is based on science, Goodwin continued, nor do consumers receive any information about dose, potency, side effects or risks from short-term and long-term use of cannabis except from the shops and companies that sell it.

“If you consider that alcohol and cigarettes have decades of data and public health campaigns aimed at preventing youth, especially those with asthma, from initiating use, it is illogical that the same is not in effect for cannabis,” she said.

Reference:

• Asthma rates climb for high school students as cannabis use increases. https://www.publichealth.columbia.edu/news/asthma-rates-climb-high-school-students-cannabis-use-increases. Published Jan. 29, 2024. Accessed Jan. 31, 2024.

For more information:

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