HPV vaccine completion rate more than halved since its introduction
MedWire News: The proportion of insured girls and young women completing the human papillomavirus (HPV) vaccine series has dropped significantly since the vaccine was approved in 2006, US study data show.
The steepest decline - up to 63% - was observed among those aged 9 to 18 years, the age group that derives the greatest benefit from the quadrivalent vaccine, which should be administered in three doses over 6 months.
"The first generation of women that could benefit from the only HPV-related cancer vaccine in existence is missing the opportunity," said lead author Abbey Berenson (University of Texas Medical Branch, Galveston) in a press statement. "This vaccine prevents one of the most devastating cancers in women."
Berenson and team used administrative data from a private insurance company to examine whether the percentage of insured women who complete the HPV vaccine series has changed over time, and how provider type and age at initiation affects rates of completion.
The study included 271,976 girls and young women in whom the HPV vaccine series was initiated between 2006 and 2009 and who had been continuously enrolled in their respective insurance plan for 365 days after vaccine initiation.
As reported in Cancer, just 38.2% received all three vaccine doses within 365 days. In all but one age group (age 27 years and older), the researchers observed a considerable drop in the number of girls who completed the vaccine series over time.
Specifically, the completion rate fell by 63% between 2006 and 2009 in those aged 9-12 years, and by 62% and 49% in those aged 13-18 and 19-26 years, respectively.
Berenson said that among the 9-12 and 13-18-year-olds, the drop may be at least partly attributable to parents not being accustomed to taking older children to the doctor more than once or twice each year and rarely making appointments for this age group solely around vaccines.
In addition to the declining completion rates, researchers found that girls who received the first dose from a gynecologist or obstetrician were more likely to complete the vaccine series than those who received the first dose from a pediatrician.
They also observed an increase in the proportion of female patients who received only the first vaccine dose, from 22.4% in 2006 to 48.9% in 2009. This may indicate that physicians are focusing more on initiating the vaccine series as time passes, but may not be following up with their patients for subsequent doses, they write.
"It appears that patients and parents do not understand that all three shots of the vaccine are required for HPV protection, and that perhaps physicians are not doing a good enough job of educating and reminding patients to ensure completion," said Berenson.
The researchers suggest that "calling or texting patients or their parents may be important methods of increasing HPV vaccine series completion among this population."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
By Laura Cowen