ABSTRACT
Women infected with multiple human papillomavirus (HPV) types seem to be at higher risk of cervical intraepithelial neoplasia, although there is controversy about whether coinfections are associated with lower or higher grades of dysplasia. There is no established risk factor profile for infection with multiple HPV types. We analyzed data from a prospective cohort of 2,075 Brazilian women to identify determinants of HPV coinfection. Cervical specimens were collected for cytology and HPV DNA detection. Data on baseline and time-dependent putative risk factors were obtained by interview. Baseline predictors of HPV coinfection included younger age, greater number of recent sexual partners, a history of condyloma but not of other sexually transmitted diseases, and younger age at first sexual intercourse. In repeated measures analyses, there was a weak positive association between the number of sexual partners in the time interval between two study visits and the risk of coinfection. Our results suggest that the risk factor profile for HPV coinfection among HPV-infected women shares several similarities with risk factors for any HPV infection.
Subject(s)
Papillomaviridae/pathogenicity , Papillomavirus Infections/pathology , Uterine Cervical Dysplasia/virology , Uterine Cervical Neoplasms/virology , Adolescent , Adult , Age Factors , Brazil , Coitus , DNA, Viral/analysis , Female , Humans , Middle Aged , Polymerase Chain Reaction , Prospective Studies , Risk Factors , Sexually Transmitted Diseases , Uterine Cervical Neoplasms/etiology , Uterine Cervical Dysplasia/etiologyABSTRACT
BACKGROUND: Few aspects of the occurrence of infections with multiple HPV types have been described. Since the immunity conferred by vaccines is type-specific, the epidemiology of such coinfections needs to be addressed. GOAL: The goal of the study was to document the prevalence and incidence of infection with multiple HPV types and the distribution of HPV types in coinfections. STUDY DESIGN: In a prospective cohort of 2075 Brazilian women, cervical specimens were collected for cytology and HPV detection. Information on potential risk factors was obtained by interview. RESULTS: The prevalence of HPV coinfections was 3% among cytologically normal women, 10% among women with ASCUS, 23% among those with LSIL, and 7% among those with HSIL. The incidence rate of coinfection declined markedly with age (Ptrend<0.001). Some HPV types co-occurred less frequently than expected, namely, HPV 16 and 18 occurring with other oncogenic HPV types and HPV 6/11. CONCLUSION: We have observed that occurrence of HPV coinfection was dependent both on age and on the presence of cytologic abnormalities. These results may have implications for vaccine development and for public health decisions about vaccination programs.