Factors predicting intermediate endpoints of cervical cancer and exposure to human papillomavirus (HPV) infections in young women screened as potential targets for prophylactic HPV vaccination in south of Brazil

OBJECTIVE: To explore the predictors of intermediate endpoints of cervical cancer in 500 women living in Porto Alegre. STUDY DESIGN: Five hundred randomly selected women (mean age 20.3 years, range 15-25) were screened using PCR detecting 25 HPV types (HPV6, 11, 16, 18, 31, 33, 34, 35, 39, 40, 42, 43, 44, 45, 51, 52, 53, 54, 56, 58, 59, 66, 68, 70, and 74). Women were interviewed and serum samples were analysed for antibodies to HPV16 and HPV18 VLPs. Regression models were constructed to analyse predictive factors for (a) HPV PCR status, (b) HPV16-seropositivity, (c) HPV18-seropositivity, and (d) SIL in the PAP smear, used as intermediate endpoints of cervical cancer. RESULTS: Specific HPV types were identified in 137 (27.4%) of the 157 (31.4%) PCR-positive women. PAP test result was the most powerful independent predictor of HPV status in PCR (p = 0.0001), followed by the sexual activity started (p = 0.001) (adjusted OR 34.075, 95% CI: 4.650-249.715). PAP test SIL was independently predicted only by the HPV PCR status (p = 0.0001) (OR 7.561, 95% CI: 2.787-20.514). HPV16 and HPV18 serostatus were the most significant predictors of each other (p=0.0001), and the life-time number of sexual partners was more significant (p=0.001) predictor of HPV16 than HPV18 serostatus (p = 0.049). CONCLUSION: These data are useful in evaluating the exposure status of the women to the risk factors of cervical cancer in south of Brazil.