Dr. Kim Capone, Lead educator of SHWI and Chief Science Officer for Vaginal Biome Science.
Background: Cervical Cancer Disparities
Native American women face a significantly higher risk of cervical cancer compared to non-Hispanic White (NHW) women, with roughly double the incidence and mortality rates. Research suggests that imbalances in the vaginal microbiome, termed vaginal dysbiosis, may increase susceptibility to HPV infection, persistence, and subsequent progression to cervical cancer.
Not surprisingly, there are limited data on the vaginal microbiome in Native American communities. To address this gap, a recent study entitled "Viewing Native American Cervical Cancer Disparities through the Lens of the Vaginal Microbiome," investigated the role of vaginal microbiome imbalances, termed vaginal dysbiosis, and the connection to high-risk HPV infections and chronic inflammation—two critical factors in cervical cancer development that may disproportionately affect Native American women.
Study Overview and Methodology
In this study, 31 women aged 18 to 55 years who were premenopausal were recruited from the Native Americans for Community Action (NACA) Family Health Center in Flagstaff, Arizona. The group consisted of 16 Native American women and 15 non-Native women. Each participant provided vaginal swabs, which were analyzed for microbial composition using 16S rRNA gene sequencing, as well as HPV status and levels of immune markers associated with inflammation. Data collection also included sociodemographic and health information to examine potential connections between social factors and microbiome health.
The study’s objective was to determine if differences in the vaginal microbiome could explain part of the increased cervical cancer risk observed among Native American women and whether specific social determinants of health impacted vaginal microbial health in this population.
Key Findings
- Microbial Composition and Dysbiosis: The study revealed that only 44% of Native American women had a Lactobacillus-dominant microbiome, compared to 58% of non-Native women. Lactobacillus species, particularly L. crispatus, are associated with a healthy vaginal environment and protection against pathogens, including high-risk HPV. In contrast, dysbiotic microbiomes, which lack sufficient Lactobacillus, were more common among Native American women, increasing their vulnerability to HPV infection and persistence.
- HPV and Inflammatory Responses: High-risk HPV strains were detected in 22.6% of participants, including five Native American women. This aligns with findings that women with dysbiotic microbiomes, particularly those high in bacteria like Sneathia and Prevotella, exhibit increased rates of HPV. The study also found elevated pro-inflammatory cytokines, such as IL-1β and TNFα, in participants with dysbiotic microbiomes. Chronic inflammation in the cervicovaginal environment may foster HPV persistence and progression to cervical dysplasia, adding to the cancer risk.
- Sociodemographic Influences on Microbiome Health: Native American participants from larger households or with lower educational attainment were more likely to have a Lactobacillus-depleted microbiome. Additionally, higher body mass index (BMI) was associated with greater microbial imbalance. These associations suggest that social determinants, including household structure, education, and overall health, may influence vaginal health and, consequently, cancer risk.
Conclusion and Implications
This study sheds light on how the vaginal microbiome may contribute to cervical cancer disparities in Native American women, underscoring the combined impact of biological and social factors. Findings suggest that addressing vaginal health through microbiome-supportive interventions—such as appropriately designed vaginal care products, probiotics, HPV vaccinations, and regular screenings—could be valuable in reducing cancer risks. Furthermore, the study highlights the need for culturally attuned healthcare initiatives that improve screening and care access for Native American communities.
Future research, particularly longitudinal studies, could deepen understanding of how the microbiome influences HPV persistence and progression over time. Ultimately, integrating microbiome support into cervical cancer prevention strategies may help reduce health disparities and promote equitable health outcomes for Native American women.