[Study on cervical intraepithelial neoplasia in relation to human papillomavirus and co-factors: a case-control study...

This study was to elucidate the role of human papillomavirus (HPV) types and cofactors in the development of cervical intraepithelial neoplasia (CIN).

Two hundred and twelve women with CIN and 427 women with normal cervical cytology (control group) were recruited from China and Australia. A questionnaire was administered to each participant to obtain the demographic and risk factor information. Cervical biopsies or smears were taken to detect HPV DNA by PCR and to identify HPV types by direct sequencing and/or Amplicor hybridisation. Data were analyzed by logistic regression.

HPV prevalence rates of specimens from Chinese and Australian were 11% and 15% among controls (P >0.05), with 99% and 85% of CINs (P<0.001), respectively. The presence of any type of HPV DNA was strongly associated with CIN with OR 43.3 for Chinese and OR 541.6 for Australian women. The strongest risk was for HPV16,followed by HPV31 in Australians, but HPV58, 59 in Chinese women. The risk for multiple HPV infection was stronger in the Australians than that in the Chinese cohort. Except for HPV infection, educational attainment was unexpectedly associated with an increased risk for CIN in Chinese, and cancer history in family was a risk factor for Australians. For the combined cohorts, educational attainment, and frequency of vitamin consumption were identified to be risk factors for CIN.

Cervical HPV DNA was a major risk factor, with the highest relative risk for type 16 HPV infection for CIN. There were variations in the distribution of HPV genotypes and cofactors in China versus Australia and in CIN.