[Prevalence of human papillomavirus infection and risk of cervical cancer or precancerous lesions in 15 years follow up: a prospective cohort study].

ABSTRACT

Objective: To evaluate the 15 years changing trends of prevalence of high risk HPV (HR-HPV) infection and the risks of cervical cancer and precancerous lesions (CIN2+ ) among a Chinese rural population. Methods: The screening cohort with 1 997 women aged 35 to 45 years old was built in 1999 in Xiangyuan County, Shanxi province (SPOCCS-I) and followed up by cytology and HR-HPV testing in the years of 2005, 2010, and 2014. The changes of HR-HPV prevalence and the risks of cervical precancerous lesions with CIN2+ as the endpoints were analyzed during the past 15 years. Results: The detection rates of HPV infection and CIN2+ were 15.7%-22.3% and 1.1%-4.3% for the baseline visit and the other 3 follow-ups, respectively. The cumulative risk of CIN2+ in HR-HPV positive women at baseline was significantly higher than HR-HPV negative women (P<0.01) during the 15-year follow-up. The risk of CIN2+ in the four-times HPV positive group was 40.0%, while the group with four-times negative HPV results was 0.6% (Adjusted RR = 55.0, 95% CI 11.3 to 268.4). Conclusions: The prevalence of HR-HPV infection and CIN2+ lesions were high in Xiangyuan county during the 15 years. HR-HPV positivity elevated the risk of CIN2+ compared to women whose HR-HPV test was negative. The risks of CIN2+ incidence in 6 years were low among women with negative HR-HPV test. The risk of CIN2+ increased with the numbers of HPV infection events. The screening interval could be extended to 5-6 years.