State laws allowing teenager consent to HPV vaccine result in higher immunization rates

Study findings published in JAMA Pediatrics reported a “positive association” between states with laws allowing teenager consent to HPV vaccination and the corresponding immunization rate.

Sangini S. Sheth, MD, MPH, FACOG, an associate professor and director of diversity, equity and inclusion in the department of obstetrics, gynecology and reproductive sciences at Yale School of Medicine, co-authored the letter along with colleagues from Yale, Pfizer Vaccine Research and Development and Kaiser Permanente Bernard J. Tyson School of Medicine.

The impetus for the study, Sheth told Healio, was reading about a teenager who lived in a state that did not permit adolescent consent regarding vaccinations. Although his parents were opposed to vaccines, the teenager chose to receive his inoculations when he turned 18 years old.

“So, when I read that piece, I wondered what the impacts of these laws were and how this affects the situation in different states,” Sheth said. “I wanted to understand the numbers behind it.”

Sheth and colleagues retrieved data from the CDC’s annual National Immunization Survey for Teens (NIS-Teens) for the years 2015 to 2018, which included 81,899 adolescents (mean age, 15 years; 49% girls).

“We were looking specifically at HPV vaccine rates, and at the rates of getting the first dose and of completing the vaccine series,” Sheth said. “We analyzed the cohort by defining for each adolescent [if they] would have been able to consent to get the vaccine on their own without parental involvement or not. In order to determine that, we went through laws and identified which states had these laws allowing for adolescent consent and in what year and for what age because that can differ by state. And then by doing that categorization, we were able to then label for each adolescent whether they would have been able to give consent or not.”

In states where adolescents were permitted to consent, 67.9% initiated the HPV vaccine series, compared with 61.4% in states where they were not permitted to consent (adjusted OR = 1.16; 95% CI, 1.01-1.34). The rates of vaccine series completion were lower in both groups — 53.7% among adolescents permitted to consent compared with 47.9% among those not permitted to consent (aOR = 1.06; 95% CI, 0.94-1.21).

“In the sensitivity analysis, initiation of the vaccine series remained significantly associated with the ability to consent (aOR = 1.16; 95% CI, 1.01-1.34),” the authors wrote.

“We did find that there was some association with seeing an adolescent that would have been able to give consent to get their own vaccine, and specifically, the association with a higher rate of initiation of HPV vaccine series,” Sheth said. “What's less surprising, once we saw the data, is that there was an association with the initiation of the series, but not with the completion of the series.”

Sheth added that there was “more to be explored here,” and said she would like to see similar studies done for other vaccine-preventable diseases.

“I think we've started a conversation here that needs to be further explored,” Sheth said.