Background:
Despite over a decade of availability, U.S. HPV vaccination rates remain low, with rural adolescents lagging 10-16 percentage points behind their urban peers, leading to preventable HPV-related cancers. This study examines the impact of rurality and insurance stability on HPV missed vaccination opportunities (HPV-MVOs) among children/adolescents (C/A).
Methods:
We analyzed Utah Statewide Immunization Information Systems (USIIS) data from 1/1/2017 to 5/19/2023, focusing on 685,614 C/A aged 9-18 years with race/ethnicity data. Insurance stability was categorized based on public insurance use. HPV-MVOs were identified as instances where a vaccination visit occurred, but the individual received an immunization other than the HPV vaccine that was due or overdue, using a 3-week shifting time window. Logistic regression and mediation analyses, guided by prior research and Directed Acyclic Graphs (DAGs), were used to assess the impact of rurality and insurance stability on HPV-MVO. Effect Measure Modification (EMM) was examined to explore how these relationships differ across racial and ethnic groups. Mediation analysis investigated the role of insurance stability in mediating rurality’s effect on HPV-MVO, with race/ethnicity as potential confounders. Moderated mediation assessed how rurality’s impact on insurance stability varies by racial/ethnic group. Analyses performed in R.
Results:
Of C/A aged 9-18, 47.1% did not receive any HPV doses, and 70% had at least one HPV-MVO, averaging 2.14 HPV-MVO per individual (SD=1.56). Rural C/A had a slightly higher likelihood of missing an HPV dose compared to urban peers (OR=1.04, 95% CI: 1.02-1.06). Latino/a C/A had higher odds (OR=1.26, 95% CI: 1.13-1.42) of experiencing HPV-MVO, while American Indian/Alaska Native, Biracial, Black, and Hawaiian/Pacific Islander C/A had lower odds compared to White C/A. Insurance stability paradoxically increased the likelihood of HPV-MVO (aOR=1.15, p<0.001). About 17.7% of rurality’s effect on HPV-MVO was mediated by insurance stability (p<0.001). Moderated mediation revealed significant interactions, with American Indian/Alaska Native and Asian C/A showing greater reductions in HPV-MVO with stable insurance compared to White C/A. Latino/a C/A showed no significant difference from White C/A.
Conclusions:
Insurance stability partially mediates the effect of rurality on HPV-MVO and varies across racial and ethnic groups, highlighting the need for tailored interventions.