A peak in prevalence of human papillomavirus (HPV) infection among women at around age 50 years may reflect a reactivation of an old HPV infection rather than a newly acquired one, according to a study published today in the Journal of Infectious Diseases.
The prevalence of HPV infection is highest among younger women who have recently initiated sexual activity. In many cases, the virus is no longer detectable after 2 years, suggesting that the body may have cleared the virus. However, recent evidence suggests that infection may become latent. A large international analysis had suggested a second peak of HPV prevalence at menopause in West Africa, Central America, and South America but not in North America, Europe, or Southeast Asia. Now, however, a new 2-year cohort study in the United States suggests a similar late-life peak in prevalence exists in US women.
The researchers analyzed data and specimens collected from 843 women aged 35 to 60 years at Baltimore outpatient clinics. They found that prevalence was lower among older cohorts of women with fewer than 5 lifetime sexual partners, but a more complex pattern was seen among women with 5 or more lifetime sexual partners. The prevalence of HPV infection was comparatively low among these women aged 35 to 40 years, was higher among such women aged 40 to 54 years, and was lower again for those aged 55 to 60 years. The pattern was similar whether women had recently had a new sexual partner or not, suggesting the pattern was not necessarily caused by a new infection. The finding suggests that HPV infections among older women are often likely due to reactivation of the virus, but more research is needed to confirm this.
The researchers also found that although the risk of having HPV was elevated in all women with 5 or more sexual partners compared with women who had fewer lifetime partners, the HPV risk associated with having more sexual partners was substantially greater for women who came of age during the sexual revolution.
“Our historical experience with HPV and cervical neoplasia in postmenopausal women may not be very predictive of the experience of the baby boomer generation of women who are now entering the menopausal transition at a higher risk than their mothers,” said lead author Patti E. Gravitt, PhD, of Johns Hopkins Bloomberg School of Public Health, in a statement.
The authors note the findings also suggest that for women with a higher risk of HPV infection, longer follow-up through menopause is advisable to assess the risk of cervical cancer in this population.