Persistent poverty disparities in incidence and outcomes among oral and pharynx cancer patients

PURPOSE

Disparities in oral cavity and pharyngeal cancer based on race/ethnicity and socioeconomic status have been reported, but the impact of living within areas that are persistently poor at the time of diagnosis and outcome is unknown. This study aimed to investigate whether the incidence, 5-year relative survival, stage at diagnosis, and mortality among patients with oral cavity and pharyngeal cancers varied by persistent poverty.

METHODS

Data were drawn from the SEER database (2006-2017) and included individuals diagnosed with oral cavity and pharyngeal cancers. Persistent poverty (at census tract) is defined as areas where ≥ 20% of the population has lived below the poverty level for ~ 30 years. Age-adjusted incidence and 5-year survival rates were calculated. Multivariable logistic regression was used to estimate the association between persistent poverty and advanced stage cancer. Cumulative incidence and multivariable subdistribution hazard models were used to evaluate mortality risk. In addition, results were stratified by cancer primary site, sex, race/ethnicity, and rurality.

RESULTS

Of the 90,631 patients included in the analysis (61.7% < 65 years old, 71.6% males), 8.8% lived in persistent poverty. Compared to non-persistent poverty, patients in persistent poverty had higher incidence and lower 5-year survival rates. Throughout 10 years, the cumulative incidence of cancer death was greater in patients from persistent poverty and were more likely to present with advanced-stage cancer and higher mortality risk. In the stratified analysis by primary site, patients in persistent poverty with oropharyngeal, oral cavity, and nasopharyngeal cancers had an increased risk of mortality compared to the patients in non-persistent poverty.

CONCLUSION

This study found an association between oral cavity and pharyngeal cancer outcomes among patients in persistent poverty indicating a multidimensional strategy to improve survival.

Parents' perspectives on dental team as advisors to promote HPV vaccination among Spanish adolescents

PURPOSE

Human papillomavirus (HPV) is a prevalent sexually transmitted infection responsible for many anogenital and oropharyngeal cancers. Dental care providers have the potential to influence vaccine uptake, yet little is known about how patients perceive their role in HPV education and prevention.

METHODS

Parents of adolescents aged 9 to 17 years (n = 375) were recruited from Valdeorras District Hospital (Galicia, Spain) to investigate parents' attitudes concerning the involvement of dental care providers in discussions related to HPV. A survey was distributed to the participants, and 343 (91.5%) were included in the analysis.

RESULTS

In general, nearly half of the parents reported feeling comfortable regarding discussing HPV with their dentist. Participants described more comfort with dentists than with dental hygienists. Parents' comfort levels were influenced by various social determinants of health, including education level, marital status, geographic origin, and child vaccination status (p > 0.05).

CONCLUSION

Parents reported varying comfort levels when discussing HPV and its vaccine with dental professionals, displaying a preference for dentists. Dental settings have the potential to promote vaccination, but the existence of ongoing barriers needs to be addressed.

Individual and Geospatial Determinants of Health Associated With School-Based Human Papillomavirus Immunization in Alberta: Population-Based Cohort Study

BACKGROUND

Human papillomavirus (HPV) infection causes nearly all cervical cancer cases and is a cause of anogenital and oropharyngeal cancers. The incidence of HPV-associated cancers is inequitable, with an increased burden on marginalized groups in high-income countries. Understanding how immunization status varies by material and social deprivation, health system, and geospatial factors is valuable for prioritizing and planning HPV immunization interventions.

OBJECTIVE

The objective of this study was to describe school-based HPV immunization rates by individual and geospatial determinants of health in Alberta, Canada.

METHODS

Health administrative data for male and female individuals born in 2004 in Alberta were used to determine HPV immunization status based on age and the number of doses administered in schools during the 2014/2015-2018/2019 school years. Immunization status and its relationship with material and social deprivation and health system factors were assessed by a logistic regression model. Geospatial clustering was assessed using Getis-Ord Gi* hot spot analysis. Mean scores of material and social deprivation and health system factors were compared between hot and cold spots without full HPV immunization using independent samples t tests. A multidisciplinary team comprising researchers and knowledge users formed a co-design team to design the study protocol and review the study results.

RESULTS

The cohort consisted of 45,207 youths. In the adjusted model, the odds of those who did not see their general practitioner (GP) within 3 years before turning 10 years old and not being fully immunized were 1.965 times higher (95% CI 1.855-2.080) than those who did see their GP. The odds of health system users with health conditions and health system nonusers not being fully immunized were 1.092 (95% CI 1.006-1.185) and 1.831 (95% CI 1.678-1.998) times higher, respectively, than health system users without health conditions. The odds of those who lived in areas with the most material and social deprivation not being fully immunized were 1.287 (95% CI 1.200-1.381) and 1.099 (95% CI 1.029-1.174) times higher, respectively, than those who lived in areas with the least deprivation. The odds of those who lived in rural areas not being fully immunized were 1.428 times higher (95% CI 1.359-1.501) than those who lived in urban areas. Significant hot spot clusters of individuals without full HPV immunization exist in rural locations on the northern and eastern regions of Alberta. Hot spots had significantly worse mean material deprivation scores (P=.008) and fewer GP visits (P=.001) than cold spots.

CONCLUSIONS

Findings suggest that material and social deprivation, health system access, and rural residency impact HPV immunization. Such factors should be considered by public health professionals in other jurisdictions and will be used by the Alberta co-design team when tailoring programs to increase HPV vaccine uptake in priority populations and regions.

High prevalence of anal high-risk HPV infection among transwomen: estimates from a Brazilian RDS study

INTRODUCTION

As the leading sexually transmitted infection worldwide, human papillomavirus (HPV) may disproportionately affect transwomen. We aimed to estimate anal HPV prevalence, especially focusing on high-risk (hr)-HPV types and evaluate their associated factors among transwomen living in Rio de Janeiro, Brazil.

METHODS

Transwomen enrolled in a respondent-driven sampling (RDS)-based survey conducted between August 2015 and January 2016 self-collected anal samples, which were promptly stored at minus 80°C. After DNA extraction, HPV detection and genotyping were performed using the PapilloCheck test. We estimated HPV prevalences and evaluated the correlates of anal hr-HPV infection using a regression logistic model.

RESULTS

Out of 345 transwomen, 272 (78.8%) were included in this analysis (122 [44.9%] HIV-positive). No participant had ever received HPV vaccination. Among participants enrolled, 212 (77.9%) were positive for any anal HPV type and 165 (60.7%) for hr-HPV. Most common hr-HPV were as follows: HPV16 (17.6%), HPV68 (14.7%), HPV39 (14.3%), HPV56 (12.5%), HPV51 (11.4%) and HPV52 (11.0%). HIV-positive transwomen had three times the odds of having an hr-HPV compared to HIV-negative transwomen. Participants who had a current rectal Neisseria gonorrhoeae infection had 3.7 times the odds of being coinfected with hr-HPV. Among HIV-positive transwomen, neither antiretroviral therapy use, undetectable viral load, current and nadir CD4 counts were associated with anal hr-HPV infection.

CONCLUSIONS

Brazilian transwomen in our study exhibit some of the highest population-specific rates of HPV and hr-HPV. There is an urgent need to elucidate the burden of HPV infection, prevalence of HPV-related diseases and access to and uptake of HPV vaccination among transwomen, especially from low- and middle-income settings.

Income and education inequalities in cervical cancer incidence in Canada, 1992-2010

BACKGROUND

There is evidence of socioeconomic inequalities in cancer incidence in Canada and other countries globally, yet there is no study investigating socioeconomic inequalities in national cervical cancer incidence in Canada. Thus, the current study investigated income and education inequalities in the incidence of cervical cancer in Canada from 1992 to 2010.

METHODS

Data were derived from a linked dataset that combined cervical cancer incidence from the Canadian Cancer Registry and demographic and socioeconomic information from the Canadian Census of Population and the National Household Survey. The Concentration index approach was used to measure income and education inequalities in the incidence of cervical cancer over time.

RESULTS

National incidence of cervical cancer decreased significantly from 1992 to 2010. The age-standardized C was negative for the majority of years for both income and education inequalities, but the preponderance were not significant. Trend analyses of socioeconomic inequalities suggested an increasing concentration of cervical cancer incidence among less-educated females over the study period.

CONCLUSIONS

Over almost two decades, there were no pervasive socioeconomic inequalities in the incidence of cervical cancer in Canada. As such, policies aimed at reducing the incidence of cervical cancer should focus on the general population, irrespective of socioeconomic status.

Assessing sociodemographic differences in human papillomavirus vaccine impact studies in the United States: a systematic review using narrative synthesis

OBJECTIVES

Sociodemographic disparities in the incidence and mortality of human papillomavirus (HPV)-associated conditions have been well documented in the pre-HPV vaccine era. It is still unknown if the introduction of routine vaccination has been effective in reducing these prevaccine era inequalities. The purpose of this review was to determine the utilization of sociodemographic variables to assess for disparities in population-level HPV vaccine impact research and to evaluate the current evidence for disparities in the reduction of HPV-associated conditions after vaccine introduction in the United States (US).

STUDY DESIGN

A systematic review of the literature from January 2007 through March 2018 was carried out to identify studies evaluating the impact HPV vaccines have had on the rates of HPV infection, genital warts, and cervical dysplasia (cervical intraepithelial neoplasia grades 1+) in the US. An in-depth review was then performed to synthesize these data and to assess the way prior studies have reported and evaluated for potential disparities in the vaccine's impact within various racial, ethnic, and/or socio-economic subgroups of the population.

METHODS

Vaccine impact studies measure the change in the population-level burden of disease prelicensure versus postlicensure of the vaccine. We systematically searched PubMed/Medline and Embase, combining search terms related to the HPV vaccine, sentinel surveillance, and HPV-associated conditions. Eligible studies were those with population-level, postvaccine introduction data that were conducted in the US. Finally, a cited reference search was conducted for all included articles using the Web of Science platform that accesses three major citation indexes: Science Citation Index, Social Sciences Citation Index, and Arts and Humanities Citation Index. This allowed us to screen not only the articles that were cited by our final collection of studies but also the articles that used our selected studies as one of their references. The study protocol is registered in PROSPERO (#CRD42018107579).

RESULTS

Overall, 23 of the 4139 references retrieved assessed the population-level impact of HPV vaccines between January 1, 2007, and March 29, 2018. Among these, 13 (57%) reported sociodemographic data. Only two articles reported stratified results by sociodemographic factors, thereby allowing assessment for potential disparate impact. One of these studies described differences in the impact of the vaccine by race, ethnicity, and income.

CONCLUSION

Although approximately half of the studies that assessed the impact of the HPV vaccine measured sociodemographic characteristics, few presented results in a way that allowed for the identification of potential differences in impact between the relevant subgroups of the population. Determining to what extent, if any, vaccines are reducing known sociodemographic disparities is an important public health priority and an essential step in developing immunization strategies that are beneficial for all.

Ancillary Benefit of Increased HPV Immunization Rates Following a CBPR Approach to Address Immunization Disparities in Younger Siblings

Increasing HPV vaccination rates may decrease the disproportionately high HPV-associated disease incidence and mortality in African Americans (AA) and lower socioeconomic individuals. Data from a community-based participatory research (CBPR) study addressing immunization disparities among 19-35 month old children was analyzed to identify ancillary benefits in HPV immunization rates for adolescent siblings. Sub-study analysis inclusion criteria: AA (N = 118), 13-17 years old, younger sibling enrolled in parent study, and enrolled ≥ 9 months. Parent/caregiver interventions included: a web-based immunization toolkit with information on age-appropriate vaccines; a multimedia community outreach campaign; and reminder mailings. HPV up-to-date (UTD) status was defined as Wisconsin Immunization Registry (WIR) documentation of at least three HPV vaccines. McNemar's test compared pre/post intervention HPV status. Two dependent proportions testing compared the proportion of adolescents that became UTD in the study cohort, City of Milwaukee, and State of Wisconsin. Parents/caregivers perceived that 92% of adolescents were HPV-UTD, while only 24% had a WIR-verified HPV-UTD status. Baseline UTD status of the younger siblings 19-35 month old 4:3:1:3:3:1:4 antigen series was 63%, which increased to 86% at study completion. Adolescent's HPV-UTD immunization status increased from 30 (25%) at enrollment to 54 (46%) at study completion [p = 0.004]. A statistically significant larger proportion of adolescents became HPV-UTD in the study cohort (20%) compared to the City of Milwaukee [14%, p = 0.042] and the State of Wisconsin [14%, p = 0.046]. A culturally-tailored CBPR approach targeting parents/caregivers of younger AA children can have significant ancillary benefit to increase HPV immunization rates in adolescent siblings.

Barriers to HPV Vaccination Among Unvaccinated, Haitian American College Women

Background: Haitian women residing in the United States are disproportionately affected by cervical cancer. Human papillomavirus (HPV) vaccine has been licensed in the United States since 2006. Vaccination rates are less than optimal overall, and the rates are particularly low among young black women. We investigated barriers to HPV vaccination in a sample of Haitian American college women. Methods: Thirty self-identified Haitian American women, aged 17-26 years, were recruited from a large university campus in southeastern United States (n=30). They completed in-depth face-to-face interviews. The research team analyzed the transcripts using thematic analysis. Results: More than half of the participants (n=18) had not yet initiated the HPV vaccine series. Most of the unvaccinated participants stated that they had received a provider recommendation for the vaccine. Lack of provider recommendation, negative vaccine perception and attitudes, and side effect concerns constituted barriers to vaccination. Conclusions: Haitian American college women at high risk of cervical cancer have cited several barriers to HPV vaccination, with the most prominent being lack of physician recommendation. Healthcare providers should continue recommending the vaccine to college women as many of them may not have received a recommendation. When recommending the HPV vaccine, discussions should be framed with the intent to positively influence HPV vaccine perceptions and ultimately vaccine attitudes.

Can high overall human papillomavirus vaccination coverage hide sociodemographic inequalities? An ecological analysis in Canada

BACKGROUND

Human papillomavirus (HPV) vaccination programs have been implemented in more than 50 countries. These programs offer tremendous promise of reducing HPV-related disease burden. However, failure to achieve high coverage among high-risk groups may mitigate program success and increase inequalities. We examined sociodemographic inequalities in HPV vaccination coverage in 4 Canadian provinces (Quebec (QC), Ontario (ON), Manitoba (MB), British Columbia (BC)).

METHODS

We obtained annual HPV vaccination coverage of pre-adolescent girls at provincial and regional levels, from the start of programs to 2012/2013. Regions refer to administrative areas responsible for vaccine implementation and monitoring (there are 18/36/10/16 regions in QC/ON/MB/BC). We obtained regions' sociodemographic characteristics from Statistics Canada Census. We used univariate weighted linear regression to examine the associations between regions' sociodemographic characteristics and HPV vaccination coverage.

RESULTS

Provincial HPV vaccination coverage is generally high (QC:78%; ON:80%; MB:64%, BC:69%, 2012/13). QC had the highest provincial vaccination coverage since the program start, but had the greatest inequalities. In QC, regional HPV vaccination coverage was lower in regions with higher proportions of socially deprived individuals, immigrants, and/or native English speakers (p<0.0001). These inequalities remained stable over time. Regional-level analysis did not reveal inequalities in ON, MB and BC.

CONCLUSION

School-based HPV vaccination programs have resulted in high vaccination coverage in four Canadian provinces. Nonetheless, high overall coverage did not necessarily translate into equality in coverage. Future work is needed to understand underlying causes of inequalities and how this could impact existing inequalities in HPV-related diseases and overall program success.

Racial and ethnic differences in human papillomavirus positivity and risk factors among low-income women in Federally Qualified Health Centers in the United States

Reasons for racial/ethnic disparities in HPV infection are unclear. This study assessed racial/ethnic differences in and risk factors for HPV positivity among low-income women. Data were collected from 984 low-income women visiting Federally Qualified Health Centers across Illinois (2009-2011). Pearson chi square and Logistic regression analyses were used to examine associations with HPV positivity. Our results showed Mexican-born Hispanics had the lowest HPV positivity (16%), followed by non-Hispanic whites (29%), US-born Hispanics (35%), and non-Hispanic blacks (39%). Mexican-born Hispanics reported fewer risk behaviors for HPV positivity, including first sexual intercourse before age 16 years (9% versus 27%), multiple sexual partners in lifetime (48% versus 90%), and current cigarette smoking status (10% versus 35%) when compared to non-Hispanic whites (p<0.001). In multivariate-adjusted logistic regression, being non-Hispanic black, first sexual intercourse before age 16 years, increasing numbers of recent or lifetime sexual partners and current cigarette smoking status were associated with a higher likelihood of HPV positivity. Our findings highlight racial/ethnic differences in HPV positivity and risk factors in a population of women with similar socioeconomic characteristics. When measuring HPV risk factors within the Hispanic population, foreign-born status and other mediating factors, such as social norms and cultural characteristics, may be relevant to assess the intragroup heterogeneity.

Next generation vaccines and vectors: Designing downstream processes for recombinant protein-based virus-like particles

In recent years, the development of novel recombinant virus-like particles (VLPs) has been generating new perspectives for the prevention of untreated and arising infectious diseases. However, cost-reduction and acceleration of manufacturing processes for VLP-based vaccines or vectors are key challenges for the global health system. In particular, the design of rapid and cost-efficient purification processes is a critical bottleneck. In this review, we describe and evaluate new concepts, development strategies and unit operations for the downstream processing of VLPs. A special focus is placed on purity requirements and current trends, as well as chances and limitations of novel technologies. The discussed methods and case studies demonstrate the advances and remaining challenges in both rational process development and purification tools for large biomolecules. The potential of a new era of VLP-based products is highlighted by the progress of various VLPs in clinical phases.

Cost-effectiveness and equity impacts of three HPV vaccination programmes for school-aged girls in New Zealand

BACKGROUND

As with many high-income countries, vaccination coverage against human papilloma virus (HPV) infection is not high in New Zealand (NZ) at 47% in school-aged girls for three doses. We estimate the health gains, net-cost and cost-effectiveness of the currently implemented HPV national vaccination programme of vaccination dispersed across schools and primary care, and two alternatives: school-based only (assumed coverage as per Australia: 73%), and mandatory school-based vaccination but with opt-out permitted (coverage 93%). We also generate estimates by social group (sex, ethnic and deprivation group).

METHODS

A Markov macro-simulation model was developed for 12-year-old girls and boys in 2011, with future health states of: cervical cancer, pre-cancer (CIN I-III), genital warts, and three other HPV-related cancers (oropharyngeal, anal, vulvar cancer). In each state health sector costs, including additional health sector costs from extra life, and quality-adjusted life years (QALYs) were accumulated.

RESULTS

The current HPV vaccination programme has an estimated cost-effectiveness of NZ$18,800/QALY gained (about US$9700/QALY gained using the OECD's purchasing power parities; 95% UI: US$6900 to $33,700) compared to the status quo in NZ prior to 2008 (no vaccination, screening alone). The incremental cost-effectiveness ratio (ICER) of an intensive school-based only programme of girls, compared to the current situation, was US$33,000/QALY gained. Mandatory vaccination appeared least cost-effective (ICER compared to school-based of US$117,000/QALY gained, but with wide 95% uncertainty limits from $56,000 to $220,000). All interventions generated more QALYs per 12-year-old for Māori (indigenous population) and people living in deprived areas (range 5-25% greater QALYs gained).

INTERPRETATION

A more intensive school-only vaccination programme seems warranted. Reductions in vaccine price will greatly improve cost-effectiveness of all options, possibly making a law for mandatory vaccination optimal from a health sector perspective. All interventions could reduce ethnic and socioeconomic disparities in HPV-related disease.

Sociodemographic factors predicting mother's cervical screening and daughter's HPV vaccination uptake

BACKGROUND

Achieving high human papillomavirus (HPV) vaccine coverage may reduce inequalities in cervical cancer prevention by mitigating the inequalities seen in the cervical screening programme. This paper assesses whether the same sociodemographic factors are associated with both cervical screening and HPV vaccination.

METHODS

Girls' HPV vaccination records were linked by address to cervical screening records for their mothers in the North West of England. Index of Multiple Deprivation scores (2010) and census ethnicity data (2001) were used to investigate the association between deprivation and ethnic composition of area of residence with HPV vaccination and cervical screening uptake, along with potential differences between Primary Care Trusts (PCTs), which were responsible for vaccine delivery.

RESULTS

Deprivation was not associated with routine (12-13-year-olds) vaccination initiation, but girls living in the most deprived quintile were significantly less likely to complete the three vaccine doses (OR 0.75; 95% CI 0.63 to 0.88). Mother-daughter pairs failing to engage in either screening or vaccination were also more likely to live in deprived areas (routine vaccination OR for most deprived quintile: 2.35; 95% CI 2.00 to 2.77). There were differences between PCTs after controlling for demographic effects (OR 1.35; 95% CI 1.23 to 1.52).

CONCLUSIONS

Ensuring completion of the vaccine schedule is critical for organisations responsible for vaccine delivery in order to reduce cancer risk among girls living in deprived areas. There remains a small minority of mothers and daughters from disadvantaged backgrounds who do not participate in either cervical screening or HPV vaccination.

Different models of HPV vaccine decision-making among adolescent girls, parents, and health-care clinicians in New Mexico

OBJECTIVE

Human papillomavirus (HPV) vaccination rates in the United States have been lower than anticipated since the vaccine became widely available globally in 2006. Of particular concern are data that suggest disparities in vaccine receipt among US ethnic minority and health disparity populations such as Hispanics, who are disproportionately affected by cervical cancer. Given these trends, it is important to examine actual vaccination decision-making processes among clinicians, parents, and adolescents to identify strategies to enhance uptake.

DESIGN

We conducted a mixed-method study examining HPV vaccine decision-making, utilizing both structured questionnaires of primarily Hispanic mothers and daughters (aged 12-18) and semi-structured interviews with mothers, daughters, and health-care clinicians to more deeply investigate decision-making dynamics. Quantitative analysis was used for descriptive purposes, while qualitative analysis featured an iterative process to examine factors related to decision-making surrounding the HPV vaccine. The study was conducted in two primary care clinics serving predominantly Hispanic patients in an urban New Mexico setting through Research Involving Outpatient Setting Network (RIOS Net), a primary care practice-based research network.

RESULTS

We administered 22 questionnaires and conducted 30 interviews. We identified three aspects of vaccine delivery that were similar across clinics: availability/supply of the vaccine, favorable clinician attitudes toward the vaccine, and clinicians' competing demands. We also identified three decision-making stages (pre-encounter, encounter, and post-encounter), though we found distinct differences in decision-making processes at the two sites. We describe the differences between an encounter-based and a process-based model of decision-making, and the ways in which explanatory factors might influence the decision-making process.

CONCLUSION

Our findings suggest that factors other than race and ethnicity, such as education, socioeconomic status, and health-care access, play an important role in HPV vaccination decisions. Further research to elucidate the specific informational needs and communication strategies associated with these factors will be needed to enhance vaccine uptake.

Coverage of the English national human papillomavirus (HPV) immunisation programme among 12 to 17 year-old females by area-level deprivation score, England, 2008 to 2011

The English national human papillomavirus (HPV) immunisation programme has offered vaccination to girls aged 12 years at the start of each school year since September 2008. A catch-up programme has offered vaccination to girls up to 18 years. Delivery is predominantly school-based, with some general practitioner (GP)-based immunisation. The relationship between HPV immunisation coverage and deprivation (index of multiple deprivation, IMD) was assessed by geographical area (N=151) for each school year offered the HPV vaccine between 2008 to 2011 using the Spearman’s rank correlation coefficient, and compared to that for adequate cervical screening of women aged 25 to 49 years. Coverage at age 12 showed no significant association with IMD at the area-level (p=0.12). Within the catch-up years, there was some suggestion of higher deprivation being associated with lower coverage. This was not significant for girls offered immunisation under 16 years (in compulsory education) (p=0.09), but was more marked and statistically significant for older girls (p<0.0001). The proportion of women aged 25 to 49 years with an adequate cervical screen was negatively associated with deprivation (p<0.0001). School-based HPV immunisation delivery appears to be successfully reducing inequalities in cervical cancer control at area-level. However, the catch-up cohorts above the age of compulsory education may face increased inequality. Further investigation is needed into individual-level factors associated with coverage.

Human papillomavirus vaccination and Pap testing profile in Manitoba, Canada

BACKGROUND

Females who receive the human papillomavirus (HPV) vaccine may believe they are protected from developing cervical cancer and no longer require screening. Concern has also been expressed that vaccinated females are those that would be screened regularly. This study assesses the Pap testing behavior of vaccinated and non-vaccinated females.

METHODS

For this population-based retrospective cohort study, vaccination and screening registries were linked for 3540 vaccinated females aged 15 years and over and 9592 matched non-vaccinated females. Conditional logistic regression, the Kaplan-Meier method and Cox regression were used to examine the association between vaccination and Pap testing.

RESULTS

Vaccinated females were more likely to have had a Pap test within the year prior to the index date than non-vaccinated females (15-19 years old: OR=1.38, 95% CI 1.20-1.59; 20+ years old: OR=2.34, 95% CI 1.98-2.76). In the three-year period after the index date, vaccinated females had a significantly higher cumulative probability of having a Pap test (83.3%) than non-vaccinated females (66.1%). Females who had a Pap test within three years prior to the index date were more likely to have a Pap test after the index date (vaccinated: HR=5.03, 95% CI 4.65-5.45; non-vaccinated HR=3.97, 95% CI 3.70-4.24). Being vaccinated had a significant effect on Pap testing (15-19 years old: HR=1.54, 95% CI 1.39-1.69; 20+ years old: HR=1.87, 95% CI 1.52-2.31). 80.1% of vaccinated females who had a Pap test prior to the index date also had one subsequent to it, compared to 70.1% for non-vaccinated females. 41.1% of females had not been vaccinated nor had a Pap test.

CONCLUSION

The majority of vaccinated females continue to participate in screening, and do so at a higher rate than non-vaccinated females. Renewed efforts need to be made to include the large proportion of non-vaccinated, non-screened females in vaccination and/or screening.

Are HPV vaccination services accessible to high-risk communities? A spatial analysis of HPV-associated cancer and Chlamydia rates and safety-net clinics

PURPOSE

While HPV vaccines can greatly benefit adolescents and young women from high-risk areas, little is known about whether safety-net immunization services are geographically accessible to communities at greatest risk for HPV-associated diseases. We explore the spatial relationship between areas with high HPV risk and proximity to safety-net clinics from an ecologic perspective.

METHODS

We used cancer registry data and Chlamydia surveillance data to identify neighborhoods within Los Angeles County with high risk for HPV-associated cancers. We examined proximity to safety-net clinics among neighborhoods with the highest risk. Proximity was measured as the shortest distance between each neighborhood center and the nearest clinic and having a clinic within 3 miles of each neighborhood center.

RESULTS

The average 5-year non-age-adjusted rates were 1,940 cases per 100,000 for Chlamydia and 60 per 100,000 for HPV-associated cancers. A large majority, 349 of 386 neighborhoods with high HPV-associated cancer rates and 532 of 537 neighborhoods with high Chlamydia rates, had a clinic within 3 miles of the neighborhood center. Clinics were more likely to be located within close proximity to high-risk neighborhoods in the inner city. High-risk neighborhoods outside of this urban core area were less likely to be near accessible clinics.

CONCLUSIONS

The majority of high-risk neighborhoods were geographically near safety-net clinics with HPV vaccination services. Due to low rates of vaccination, these findings suggest that while services are geographically accessible, additional efforts are needed to improve uptake. Programs aimed to increase awareness about the vaccine and to link underserved groups to vaccination services are warranted.