Cervical cytology and multiple type HPV infection: a study of 8182 women ages 31-65.

Objective: The aim of this study is to determine the rates of single and multiple type human papillomavirus (HPV) infection in women in the United States ages 31-65 with known cervical cytology results.

Methods: Type-specific HPV analyses were conducted using the first samples of women who had HPV typing performed by Access Genetics as part of cervical cancer screening between July 2007 and May 2011. Women 31-65years at testing with associated abnormal cytology results were included. The odds of abnormal cytology (compared to normal results) for multiple vs. single HPV infections were calculated for each cytology sub-type and odds ratios (OR) and 95% confidence intervals (CI) are reported.

Results: The analysis included 8182 women. The majority (67.7%) had ASCUS cervical cytology. A total of 329 (4.0%) were positive for 2 or more HPV types. For all cervical cytology subtypes considered (ASCUS, ASCUS-H, LSIL or HSIL), women with multiple type infections were more likely to have abnormal cytology (compared to normal cytology) with the highest OR associated with HSIL (OR 1.81 (1.26-2.60)). When analyzing HPV type 16 alone, women with multiple type infections were more likely to have abnormal cytology, with the highest OR associated with HSIL cytology (OR 2.98 (1.57-5.64)). Few women had HPV type 18 infections and no results reached statistical significance. Results based on phylogenic family organization focusing on the alpha 9 phylogenic family showed similar results as HPV type 16.

Conclusions: Women ages 31-65 with multiple type HPV infections were more likely to have abnormal cytology than those with single HPV type infections.