Detection of oncogenic genital human papillomavirus (HPV) among HPV negative older and younger women after 7 years of follow-up.

The knowledge on risk factors of being human papillomavirus (HPV)-positive among older women is sparse. The aim was to determine the frequency of oncogenic HPV appearance after 7 years among initially HPV-negative women and to examine potential risk factors that influence the occurrence of HPV in older women using multiple logistic regression. For comparison, a younger cohort of women examined under identical study settings was included. This prospective cohort study comprised 1,577 older women (age 40-50 at enrolment) and 2,920 women aged 22-32. Participants were interviewed and underwent a gynecological examination at two time points (7 years apart). Cervical samples were tested for HPV using Hybrid Capture 2 (HC2) and only women who tested HC2-negative at baseline were included. The HPV prevalence among older and younger women was 6.4% and 10.7%, respectively, and there was no "second peak" observed among older women. Recent sexual partners were a strong determinant of HPV appearance irrespective of age. Lifetime number of sexual partners was a significant risk factor for HPV appearance among older women, even after adjustment for recent sexual behavior. In addition, menopause was associated with a non-significantly increased risk of HPV appearance at follow-up. In conclusion, appearance of HPV in previously HPV-negative older women may be due to both recent sexual behavior and previous exposure that is, reactivation of a latent HPV infection.