Breast cancer mortality in neighbouring European countries with different levels of screening but similar access to treatment: trend analysis of WHO mortality database
BMJ 2011; 343 doi: https://doi.org/10.1136/bmj.d4411 (Published 28 July 2011) Cite this as: BMJ 2011;343:d4411
- Philippe Autier, research director1,
- Mathieu Boniol, senior statistician1,
- Anna Gavin, director2,
- Lars J Vatten, professor3
- 1International Prevention Research Institute, 95 Cours Lafayette, 69006 Lyon, France
- 2Northern Ireland Cancer Registry, Belfast, Northern Ireland, UK
- 3Department of Public Health, Norwegian University of Science and Technology, Trondheim, Norway
- Correspondence to: P Autier philippe.autier{at}i-pri.org
Abstract
Objective To compare trends in breast cancer mortality within three pairs of neighbouring European countries in relation to implementation of screening.
Design Retrospective trend analysis.
Setting Three country pairs (Northern Ireland (United Kingdom) v Republic of Ireland, the Netherlands v Belgium and Flanders (Belgian region south of the Netherlands), and Sweden v Norway).
Data sources WHO mortality database on cause of death and data sources on mammography screening, cancer treatment, and risk factors for breast cancer mortality.
Main outcome measures Changes in breast cancer mortality calculated from linear regressions of log transformed, age adjusted death rates. Joinpoint analysis was used to identify the year when trends in mortality for all ages began to change.
Results From 1989 to 2006, deaths from breast cancer decreased by 29% in Northern Ireland and by 26% in the Republic of Ireland; by 25% in the Netherlands and by 20% in Belgium and 25% in Flanders; and by 16% in Sweden and by 24% in Norway. The time trend and year of downward inflexion were similar between Northern Ireland and the Republic of Ireland and between the Netherlands and Flanders. In Sweden, mortality rates have steadily decreased since 1972, with no downward inflexion until 2006. Countries of each pair had similar healthcare services and prevalence of risk factors for breast cancer mortality but differing implementation of mammography screening, with a gap of about 10-15 years.
Conclusions The contrast between the time differences in implementation of mammography screening and the similarity in reductions in mortality between the country pairs suggest that screening did not play a direct part in the reductions in breast cancer mortality.
Footnotes
Contributors: PA conceived and designed the study. All authors collected and interpreted the data, edited the manuscript, and approved the final version of the manuscript for submission. PA and MB analysed the data. PA, AG, and LJV wrote the manuscript. PA is the guarantor.
Funding: The institutions in which the authors work had no influence on the conduct of the research or the writing of the paper. The work of the Northern Ireland Cancer Registry is funded by the Public Health Agency for Northern Ireland.
Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Ethical approval: Not required.
Data sharing: The WHO mortality database is available at www.who.int.
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