Cervical cancer : incidence, screening and prognosis among immigrant women in Sweden

Immigrant studies may help further our understanding of the aetiology of cervical cancer and improve its prevention. The overall aim of this thesis is to study the risk of cervical cancer among immigrant women in Sweden, their cervical screening attendance and their prognosis after cervical cancer diagnosis. Quantitative cohort study designs using data from population-based registers were carried out and analysed using Poisson regression and Cox proportional hazard models. A quantitative explorative design was used to analyse the results of focus group discussions (FGDs) according to the principles of content analysis.

Compared to Swedish-born women, immigrant women in Sweden had a higher relative risk of invasive cervical cancer, particularly women from Denmark, Norway and Central America; the opposite was true for immigrant women from Eastern Africa and South Central Asia. Moreover, age at immigration and follow-up time were important effect modifiers for the risk of cervical cancer among immigrant women (Study I). Average cervical screening attendance was 62% and 49% among Swedish-born and immigrant women, respectively, and was lowest among women who immigrated at older ages. Adherence to recommended screening intervals is very effective in preventing cervical cancer (Study II). The qualitative study using FGDs revealed a complex rationale for postponing cervical screening that included aspects related to immigration itself, including competing needs, organisational and structural factors, and differences in mentality (Study III). Non-Nordic immigrant women had a slightly lower risk of dying from cervical cancer than Swedish-born women. Both Swedish-born and immigrant women with symptomatic cervical cancer showed a 3 to 4-fold excess mortality compared to screening-detected cases. Both immigrant and Swedish-born women with low socioeconomic status had an excess risk of dying from cervical cancer (Study IV).

In conclusion, these results suggest a need for targeted prevention both among Swedish-born and immigrant women with low socioeconomic status and immigrant women at high-risk for cervical cancer, particularly those from Denmark, Norway and Central America, and specifically women who immigrate at older ages, during the first 10 years after their arrival. The results on cervical cancer prognosis indicate that there is equal access to health care in Sweden, irrespective of country of birth. The rationale of immigrant women in FGDs to postpone cervical screening reveals an opportunity to motivate these women to attend.

List of scientific papers

I. Fatima Azerkan, Kazem Zendehdel, Per Tillgren, Elisabeth Faxelid and Pär Sparén. Risk of cervical cancer among immigrants by age at immigration and follow- up time in Sweden, from 1968 to 2004. International Journal of Cancer. 2008; 123: 2664-2670.
https://doi.org/10.1002/ijc.23843

II. Fatima Azerkan, Pär Sparén, Sven Sandin, Per Tillgren, Elisabeth Faxelid and Kazem Zendehdel. Cervical screening participation and risk among Swedish-born and immigrant women in Sweden. International Journal of Cancer. 2012; 130: 937-947.
https://doi.org/10.1002/ijc.26084

III. Fatima Azerkan, Catarina Widmark, Pär Sparén, Elisabete Weiderpass, Per Tillgren and Elisabeth Faxelid. When life got in the way: How Danish and Norwegian immigrant women in Sweden reason about cervical screening and why they postpone attendance. [Submitted]

IV. Fatima Azerkan, Jonas Hällgren, Kazem Zendehdel, Sven Sandin, Sanna Tiikkaja, Ruslan Fomkin, Elisabete Weiderpass and Pär Sparén. Cervical cancer prognosis by immigration status, cervical screening attendance and socioeconomic status in Sweden. [Submitted]