Mammographic density and markers of socioeconomic status: a cross-sectional study

BMC Cancer

Research Article

Isabel dos Santos Silva¹  Zoe Aitken¹  Kate Walker¹  Bernardine H Stegeman²  Petra A Wark³  Valerie A McCormack⁴  Sue M Moss⁵ 

[1] Cancer Research UK Epidemiology and Genetics Group, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK;Cancer Research UK Epidemiology and Genetics Group, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK;Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, The Netherlands;Cancer Research UK Epidemiology and Genetics Group, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK;Imperial College London, Department of Epidemiology and Public Health, St Mary's Campus, Norfolk PlaceLondon, UK;Cancer Research UK Epidemiology and Genetics Group, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK;International Agency for Research on Cancer, 150 Cours Albert Thomas, 69008, Lyon, France;Screening Evaluation Unit, Institute of Cancer Research, 15 Cotswold Rd, SM2 5NG, Belmont, Sutton, Surrey, UK;

关键词: Breast Cancer Risk;    Mammographic Density;    Reproductive Factor;    Breast Cancer Risk Factor;    Percent Density;   

DOI  :  10.1186/1471-2407-10-35

 received in 2009-08-25, accepted in 2010-02-09,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundSocioeconomic status (SES) is known to be positively associated with breast cancer risk but its relationship with mammographic density, a marker of susceptibility to breast cancer, is unclear. This study aims to investigate whether mammographic density varies by SES and to identify the underlying anthropometric, lifestyle and reproductive factors leading to such variation.MethodsIn a cross-sectional study of mammographic density in 487 pre-menopausal women, SES was assessed from questionnaire data using highest achieved level of formal education, quintiles of Census-derived Townsend scores and urban/rural classification of place of residence. Mammographic density was measured on digitised films using a computer-assisted method. Linear regression models were fitted to assess the association between SES variables and mammographic density, adjusting for correlated variables.ResultsIn unadjusted models, percent density was positively associated with SES, with an absolute difference in percent density of 6.3% (95% CI 1.6%, 10.5%) between highest and lowest educational categories, and of 6.6% (95% CI -0.7%, 12.9%) between highest and lowest Townsend quintiles. These associations were mainly driven by strong negative associations between these SES variables and lucent area and were attenuated upon adjustment for body mass index (BMI). There was little evidence that reproductive factors explained this association. SES was not associated with the amount of dense tissue in the breast before or after BMI adjustment. The effect of education on percent density persisted after adjustment for Townsend score. Mammographic measures did not vary according to urban/rural place of residence.ConclusionsThe observed SES gradients in percent density paralleled known SES gradients in breast cancer risk. Although consistent with the hypothesis that percent density may be a mediator of the SES differentials in breast cancer risk, the SES gradients in percent density were mainly driven by the negative association between SES and BMI. Nevertheless, as density affects the sensitivity of screen-film mammography, the higher percent density found among high SES women would imply that these women have a higher risk of developing cancer but a lower likelihood of having it detected earlier.

【 授权许可】

Unknown   
© Aitken et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.