BALTIMORE – , according to a retrospective cohort study of commercially insured youth presented at the annual clinical and scientific meeting of the American College of Obstetricians and Gynecologists. The research was published ahead of print in Human Vaccines and Immunotherapeutics.
Changing attitudes
“These findings are novel because they emphasize starting at age 9, and that is different than prior studies that emphasize bundling of these vaccines,” Kevin Ault, MD, professor and chair of the department of obstetrics and gynecology at Western Michigan University Homer Stryker MD School of Medicine and a former member of the CDC’s Advisory Committee on Immunization Practices, said in an interview.
Dr. Ault was not involved in the study but noted that these findings support the AAP’s recommendation to start the HPV vaccine series at age 9. The Centers for Disease Control and Prevention currently recommends giving the first dose of the HPV vaccine at ages 11-12, at the same time as the Tdap and meningitis vaccines. This recommendation to “bundle” the HPV vaccine with the Tdap and meningitis vaccines aims to facilitate provider-family discussion about the HPV vaccine, ideally reducing parent hesitancy and concerns about the vaccines. Multiple studies have shown improved HPV vaccine uptake when providers offer the HPV vaccine at the same time as the Tdap and meningococcal vaccines.
However, shifts in parents’ attitudes have occurred toward the HPV vaccine since those studies on bundling: Concerns about sexual activity have receded while concerns about safety remain high. The American Academy of Pediatrics and the American Cancer Society both advise starting the HPV vaccine series at age 9, based on evidence showing that more children complete the series when they get the first shot before age 11 compared to getting it at 11 or 12.
“The bundling was really to vaccinate people by the age of 13, thinking that onset of sexual activity was after that,” study author Sidika Kajtezovic, MD, a resident at Boston Medical Center and Boston University Obstetrics and Gynecology, said in an interview. But Dr. Kajtezovic said she delivers babies for 13-year-old patients. “Kids are having sex sooner or sooner.” It’s also clear that using the bundling strategy is not making up the entire gap right now: Ninety percent of children are getting the meningococcal vaccine while only 49% are getting the HPV vaccine, Dr. Kajtezovic pointed out. “There’s a disconnect happening there, even with the bundling,” she said.
Debundling vaccines
Dr. Kajtezovic and her colleagues used a national database of employee-sponsored health insurance to analyze the records of 100,857 children who were continuously enrolled in a plan from age 9 in 2015 to age 13 in 2019. They calculated the odds of children completing the HPV vaccine series based on whether they started the series before, at the same time as, or after the Tdap vaccination.
Youth who received the HPV vaccine before their Tdap vaccine had 38% greater odds of completing the series – getting both doses – than did those who received the HPV vaccine at the same time as the Tdap vaccine. Meanwhile, in line with prior evidence, those who got the first HPV dose after their Tdap were less likely – 68% lower odds – to complete the two- or three-dose (if starting above age 14) series.
The researchers identified several other factors that were linked to completing the HPV vaccine series. Females had greater odds than did males of completing the series, as did those living in urban, rather than rural, areas. Other factors associated with completing the series included living in the Northeast United States and receiving primary care from a pediatrician rather than a family medicine physician.
Timing is important
“I am encouraged by the findings of this study,” Dr. Ault said in an interview. “However, I would have liked the authors to expand the age range a bit higher. There are data that continuing to discuss the HPV vaccine with parents and teens will increase uptake into the later teen years.”
One challenge is that research shows attendance at primary care visits declines in older adolescence. Since there is no second Tdap or meningitis shot, families need to return for the second HPV vaccine dose after those shots, though they could get the second dose at the same time as other two vaccines if they receive the first dose before age 11. There’s also evidence suggesting that providers find conversations about the HPV vaccine easier when sexual activity is not the focus.
“I often feel that, before a child reaches adolescence, they’re almost, in a way, not sexualized yet, so talking about cancer prevention for an 8- or 9-year-old sometimes sounds a little different to patients versus protecting your 12-year-old, who’s starting to go through adolescence and developing breasts” and other signs of puberty, Dr. Kajtezovic said. Keeping the focus of HPV vaccine discussions on cancer prevention also allows providers to point out the protection against anal cancer, vulvar cancer, vaginal cancer, and head and neck cancer. “They are horrible, and even if they’re treatable, they’re often very hard to treat at an advanced stage,” Dr. Kajtezovic said. “The surgery required is so life disabling and disfiguring.”
The HPV Roundtable advises continuing bundling at practices having success with it but encourages practices to consider earlier vaccination if their uptake is lagging. Quality improvement initiatives, such as earlier electronic medical record prompts and multi-level interventions in pediatric practices, have shown substantial increases in HPV vaccine uptake at 9 and 10 years old. One survey in 2021 found that one in five primary care providers already routinely recommend the HPV vaccine at ages 9-10, and nearly half of others would consider doing so.
“My hope is in the next few years, when [the CDC] refreshes their vaccine recommendations, that they will either unbundle it or move the bar a few years earlier so that you can initiate it to encourage earlier initiation,” Dr. Kajtezovic said.
Dr. Ault had no other disclosures besides prior service on ACIP. Dr. Kajtezovic had no disclosures.