Prevalence of human papillomavirus infection in women in Turin, Italy

https://doi.org/10.1016/j.ejca.2004.07.005Get rights and content

Abstract

Human papillomavirus (HPV) is recognised as necessary for the development of cervical cancer. An age-stratified random sample of 1013 women, aged 25–70 years, participating in the organised cervical screening programme in Turin, Italy was tested for 36 HPV types using polymerase chain reaction (PCR) with the general primers GP5+/GP6+. The overall HPV prevalence was 8.8%. High-risk types were found in 7.1% of women and multiple infections in 1.1%. HPV-16 was the most common type (32.6% of HPV-positive women). HPV prevalence (any type) was 13–14% at ages 25–39 years, 11.5% at age 40–44 years, and approximately 5% among older women. After age-adjustment, HPV prevalence was significantly increased in single vs married, (Odds Ratio (OR) = 2.23; 95% Confidence Interval (CI): 1.28–3.89) and decreased in parous vs nulliparous women (OR = 0.49; 95% CI: 0.31–0.78). However, the association with marital status and parity was restricted to women less than 45 years of age. In conclusion, overall, the female population of Turin showed an HPV prevalence that is intermediate compared with worldwide levels.

Introduction

Infection with high-risk types of human papillomavirus (HPV) is found in virtually all cases of cervical cancer [1] and is considered a necessary factor in invasive cervical cancer [1], [2]. This finding has stimulated interest in HPV DNA testing as a means of screening for cervical cancer [3] and in the development of prophylactic and therapeutic vaccines against HPV [4].

Before vaccines or HPV-based cervical screening can be introduced at a population level, information is needed on the age- and type-specific prevalence of HPV infection in representative samples of the female population. Few such studies have been conducted [5], [6], [7], [8], [9], [10], [11], [12], [13], particularly in Southern Europe [14], [15], and no large population-based survey of the prevalence of type-specific HPV is available for Italy.

In Turin, an organised screening programme for cervical cancer has been active for many years. All female residents aged 25–64 years are invited to have a Papanicolau (Pap) smear every 3 years, independent of their history of spontaneous screening [16]. Comparisons of the socio-demographic features of the women who do and do not participate in this programme have not shown any substantial differences [17] and, therefore, screening participants can be considered to be a reasonably representative sample of the Turin population.

We estimated the prevalence of cervical HPV infection in this population by means of a cross-sectional study, one of a number of HPV prevalence surveys being conducted by International Agency for Research on Cancer (IARC) on different continents.

Section snippets

Study population

Cervical cell samples were obtained from all women who came after invitation (between April and June 2002) for cytological analysis within the framework of the Turin organised cervical screening programme during a pilot project on the use of liquid-based cytology. Of these women, 6556 (89.4%) agreed to participate in the present study and gave their written informed consent.

A random sample of stored specimens was selected, excluding those from 559 women who (a) were pregnant, (b) had undergone

Human papillomavirus prevalence and distribution of types

HPV infection was found in 89 of the 1013 women eligible for the DNA analysis (8.8%; 95% CI: 7.0–10.5). The prevalence in the age range 25–70 years was 8.8% when standardised by age on the basis of the Turin population in 1998 and 9.5% when standardised on the basis of the world standard population. HPV DNA was found in 78 of the 997 women with normal cytological specimens (7.8%) and in 11/16 (68.8%) of those with abnormal cytology. These included 2 cases with histologically-confirmed cervical

Discussion

The prevalence of HPV DNA in our study in Turin was 8.8% in women aged 25–70 years, and decreased to 7.8% after exclusion of women with abnormal cervical cytological findings. The peak prevalence was 13.9%, in the age group 35–39 years (i.e., later than in most populations studied so far). A similar HPV prevalence was found in women aged 24–64 years in a case-control study conducted within the cervical screening programme in Florence, in central Italy. Infection with any of six high-risk HPV

Conflict of interest statement

No conflict of interest.

Acknowledgements

Financial support for this study was provided by Regione Piemonte (Project “Uso delle nuove tecnologie nello screening del cervicocarcinoma”), by the Special Project “Oncology”, Compagnia di San Paolo FIRMS and by the European Union (EU) (Europe Against Cancer, agreement SPC.2002475). We thank Moreno Demaria (Environmental Epidemiology Unit, Piedmont Environment Protection Agency) for linkage with the Turin population registry and with census data. We also thank all the staff from the Turin

References (35)

  • D.A. Galloway

    Papillomavirus vaccines in clinical trials

    Lancet Infect. Dis.

    (2003)
  • G. Ronco et al.

    Interaction of spontaneous and organised screening for cervical cancer in Turin, Italy

    Eur. J. Cancer

    (1997)
  • N. Muñoz et al.

    Role of parity and human papillomavirus in cervical cancer: the IARC multicentric case-control study

    Lancet

    (2002)
  • J.M. Walboomers et al.

    Human papillomavirus is a necessary cause of invasive cervical cancer worldwide

    J. Pathol.

    (1999)
  • International Agency for Research on Cancer. IARC monographs on the evaluation of carcinogenic risks to humans, vol....
  • J. Cuzick et al.

    A systematic review of the role of human papillomavirus (HPV) testing within a cervical screening programme: summary and conclusions

    Br. J. Cancer

    (2000)
  • R. Herrero et al.

    Population-based study of human papillomavirus infection and cervical neoplasia in rural Costa Rica

    J. Natl. Cancer Inst.

    (2000)
  • M.V. Jacobs et al.

    Distribution of 37 mucosotropic HPV types in women with cytologically normal cervical smears: the age related patterns for high-risk and low-risk types

    Int. J. Cancer

    (2000)
  • J.W. Sellors et al.

    Prevalence and predictors of human papillomavirus infection in women in Ontario, Canada

    Can. Med. Assoc. J.

    (2000)
  • E. Lazcano-Ponce et al.

    Epidemiology of HPV infection among Mexican women with normal cervical cytology

    Int. J. Cancer

    (2001)
  • M. Molano et al.

    Prevalence and determinants of HPV infection among Colombian women with normal cytology

    Br. J. Cancer

    (2002)
  • P.T.H. Ahn et al.

    Human papillomavirus infection among women in South and North Vietnam

    Int. J. Cancer

    (2003)
  • E. Matos et al.

    Prevalence of human papillomavirus infection among women in Concordia, Argentina: a population-based study

    Sex Transm. Dis.

    (2003)
  • H.R. Shin et al.

    Prevalence of human papillomavirus infection in women in Busan, South Korea

    Int. J. Cancer

    (2003)
  • J.O. Thomas et al.

    Prevalence of papillomavirus infection in Ibadan, Nigeria: a population-based study

    Br. J. Cancer

    (2004)
  • T. Agorastos et al.

    Cervical human papillomavirus infection in women attending gynaecological outpatient clinics in northern Greece

    Eur. J. Cancer Prev.

    (2004)
  • S. de Sanjosé et al.

    Cervical human papillomavirus infection in the female population in Barcelona, Spain

    Sex Transm. Dis.

    (2003)
  • Cited by (104)

    • Prevalence of oncogenic human papillomavirus in pregnant adolescents, association with colpocytological changes, risk factors and obstetric outcomes

      2022, Clinics
      Citation Excerpt :

      Nevertheless, the infection may lie dormant in some women, and persist in a minority.6 The independent risk factors associated with an HPV infection include the following: low educational level, first sexual intercourse at an early age, multiple sexual partners, multiple deliveries, smoking, patients younger than 30 years, alcohol consumption, partner belonging to an older age bracket, singlehood and the infrequent use or the absence of the use of barrier methods.7–14 Prevalence of HPV in the uterine cervix of women, in general, varies from 7.30% to 74.60%,15,16 whereas prevalence among adolescents is reported to be between 15% and 90%.17,18

    View all citing articles on Scopus
    View full text