Human Papillomavirus Vaccination Initiation and Access to Care in the US- Provider Type, Health Insurance, and Poverty Status

Background:
In 2006, quadrivalent human papillomavirus (HPV4) vaccine was recommended for routine vaccination of adolescent girls. As vaccination is costly, it is important to monitor uptake and identify potential sectors of under-immunization.

Objectives:
To examine HPV4 initiation and associations with type of vaccination provider, health insurance, and poverty status among adolescent females in the US.

Methods:
We analyzed data from the 2007 National Immunization Survey-Teen, a nationally representative random-digit-dialed telephone survey of adolescents aged 13-17 years. We collected immunization histories from vaccination providers and self-reported health insurance coverage and household poverty status from parents of teens. Teens had initiated HPV4 vaccination if they had received 1+ doses (1+HPV4). To evaluate associations between provider type, health insurance coverage, poverty status and 1+HPV4, we calculated odds ratios from logistic regression adjusted for survey design.

Results:
Immunization histories were collected on 1,432 female adolescents aged 13-17 years. Nationally, 25.1% (95% CI 22.3%, 28.1%) of female adolescents had received 1+HPV4. Compared to teens who received all vaccinations from public providers, teens receiving all vaccinations from either STD/Teen/school clinics, a mix of providers, private providers, or hospitals were significantly more likely to have 1+HPV4 [OR=3.7(CI 2.9, 4.5), 2.7(CI 2.2, 3.4), 2.7(CI 2.3, 3.1),2.5 (CI 1.9, 3.3)]. Compared to teens living in households with income >$75,000, teens living in households <$5,000 and teens in poverty were significantly less likely to have 1+HPV4 [OR=0.6 (CI 0.5,0.7), 0.5 (CI 0.4,0.6)). Compared to teens with no insurance, teens with public health insurance and teens with private insurance had significantly higher 1+HPV4 coverage (OR= 3.8 (CI 3.3, 4.4), 3.2 (CI 2.8, 3.6).

Conclusions:
One year after vaccine recommendations, one in four adolescent girls had initiated HPV4 vaccination. Vaccination initiation varied depending on provider, health insurance, and household income. Further research is needed to examine these relationships and understand how access to the vaccine influences initiation.