Stephen E. Hawes (United States of America)
University of Washington Department of EpidemiologyPresenter of 1 Presentation
ELEVATED VAGINAL PH LEVELS AND HPV AMONG SENEGALESE WOMEN (ID 663)
Abstract
Introduction
Sub-Saharan Africa has the greatest global burden of cervical cancer. While elevated levels of vaginal pH have been associated with vaginal inflammation and infection, evidence demonstrating the relationship between vaginal pH and HPV infection is not well characterized. Elevated vaginal pH may serve as a biomarker in determining risk of HPV acquisition and persistence and may inform the underlying biological mechanisms driving the interplay between the vaginal microbiota, HPV infection, and development of cervical cancer.
Methods
Between 2006 and 2011, 462 adult women participated in a longitudinal study at two outpatient clinics in Senegal, West Africa. At each of 1361 study visits, samples were collected for assessment of vaginal pH and HPV infection, and women contributed from 1 to 11 samples. A liquid bead microarray assay was utilized to identify 37 HPV types. We performed logistic regression using generalized estimating equations to calculate odds ratios for risk of HPV detection associated with level of vaginal pH, and assessed the potential impact of subject age/menopausal status, sexual partnerships, douching, and HIV status on this association.
Results
HPV was detected at 49.0% of study visits. In adjusted analyses, among pre-menopausal women, vaginal pH was not significantly associated with HPV infection. However, in menopausal/post-menopausal women, increased vaginal pH > 5.0 was strongly associated with increased HPV infection: pH 5-5.9, OR=3.0, 95% CI 1.2-7.3; pH 6.0-6.9, OR=3.5, 95% CI 1.4-8.8; pH >7.0, OR=4.8, 95% CI 1.8-12.7.
Conclusions
We found that elevated vaginal pH, known to be associated with bacterial vaginosis and indicative of an imbalanced vaginal microbiome, is associated with detection of HPV in older, menopausal/post-menopausal women. Further research to determine the composition of vaginal bacteria as it relates to HPV infection acquisition and persistence, and to assess the impact of interventions to alter the vaginal microbiome on risk for HPV, are warranted.