Barriers to Human Papillomavirus Vaccination Initiation and Completion among Adults Aged 18–26 Years in a Large Healthcare System

SIMPLE SUMMARY: This study investigated HPV vaccination rates and associated factors among 265,554 patients aged 18–26 within a large healthcare system. Alarmingly, only 30% had completed the vaccine series, far below national averages and targets. Significant disparities were found, with males less likely to be vaccinated than females and Black Americans less likely to complete vaccination despite higher initiation rates. Many patients remained unvaccinated despite recent primary care visits, highlighting missed opportunities. Low uptake, particularly among males, and disparities emphasize the urgent need for targeted interventions to improve provider communication and community education around HPV risks and vaccine benefits to increase vaccination coverage in this population. ABSTRACT: Human papillomavirus (HPV) is a common sexually transmitted infection, with over 40% prevalence in the US. Oropharyngeal cancers (OPCs) driven by high-risk HPV are increasing (up to 90%), with HPV vaccination being the only prevention available. The aim of this study was to investigate HPV vaccination among patients aged between 18 and 26 years old with at least one encounter at a large healthcare system and identify sociodemographic factors associated with vaccine initiation and completion. A cross-sectional retrospective study was conducted between 2018 and 2021, including 265,554 patients identified from the Clinical Data Warehouse. HPV vaccination status by age, sex, race/ethnicity, insurance type, primary care (PCP) visits in the past year, alcohol, tobacco, illicit drug use, and age at vaccination was examined. Overall, 33.6% of females and 25.4% of males have completed the HPV vaccine. Black Americans were 35% more likely to initiate the vaccine than White Americans but were less likely to complete the entire course. Overall, HPV vaccination prevalence was far below the Health People 2030 goal of 80%, especially in young males. This low rate is troubling, since many patients had a PCP visit and remained unvaccinated, which serves as a missed opportunity for vaccination.