ASPO Abstracts
Differences in HPV vaccination rates between pediatric, adolescent, and young adult (AYA) cancer survivors and a non-cancer comparison sample
Category: Survivorship & Health Outcomes/Comparative Effectiveness Research
Conference Year: 2021
Abstract Body:
Purpose: Vaccinations for the human papillomavirus (HPV) can reduce susceptibility of pediatric, adolescent, and
young adult (PAYA) cancer survivors to HPV-related subsequent cancers. We report on differences in HPV
vaccination rates among a Utah-based cohort of survivors and a comparison sample without cancer.
Methods: Eligible participants had record of a primary care visit at one of two large healthcare systems in Utah
during study follow-up: 2006-2016. We used vaccination records from two large healthcare systems, a statewide
vaccination record system, and an all-payer claims database linked to cancer registry records. HPV vaccination
initiation (1 dose) and completion (3 doses) were compared between cancer survivors (N=1,581) and an age and
sex-matched comparison group without cancer (N=4,522) from 2006-2016. Individuals were aged 9-21 years old
at cohort entry. Mixed-effects Poisson regression was used to estimate incidence rate ratios (IRRs) and 95%
confidence intervals (CIs) for initiation and completion. Models were stratified by sex, race, parental education,
rurality and insurance at cohort entry.
Results: Overall, initiation/completion was 17%/5% for survivors and 20%/7% for the comparison. Relative to the
comparison sample, cancer survivors were less likely to initiate the HPV vaccine (IRR=0.8, CI:0.73-0.97). In the
stratified models, initiation and completion rates were lower for survivors compared to the comparison sample
across many demographic groups. The most severe disparities in both initiation and completion were seen in male
and Hispanic survivors. Male survivors were less likely to initiate HPV vaccination (initiation: IRR=0.7, CI:0.56-
0.89). Hispanic survivors were less likely to initiate (IRR=0.5, CI:0.31-0.72) or complete (IRR=0.5, CI:0.27-0.89)
HPV vaccination.
Conclusion: PAYA cancer survivors are less likely to initiate their HPV vaccination series than their non-cancer
counterparts. Survivors who are male or Hispanic showed the highest risk for failing to initiate or complete the
HPV vaccine. Targeted interventions should be directed at PAYA survivors to raise rates of HPV vaccination with
particular care taken to include and target male and Hispanic survivors.
Keywords: HPV vaccination, Cancer Survivors