Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study
Background: Recent cohort studies have suggested an increased risk of breast cancer with long duration of smoking, and with smoking initiation before first birth. Cigarette smoking may have both carcinogenic effects and antiestrogenic effects on the breast tissue. We decided to examine the relations...
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2007
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Online Access: | https://hdl.handle.net/10037/1246 https://doi.org/10.1186/bcr1782 |
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ftunivtroemsoe:oai:munin.uit.no:10037/1246 2024-06-02T08:15:21+00:00 Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study Bremnes, Yngve Bjurstam, Nils Ursin, Giske Gram, Inger Torhild 2007-10-26 156770 bytes application/pdf https://hdl.handle.net/10037/1246 https://doi.org/10.1186/bcr1782 eng eng BioMed Central Breast Cancer Research 9(2007)no 5, R73 doi:10.1186/bcr1782 1465-5411 https://hdl.handle.net/10037/1246 URN:NBN:no-uit_munin_1062 openAccess VDP::Medical disciplines: 700::Clinical medical disciplines: 750::Oncology: 762 Journal article Tidsskriftartikkel Peer reviewed 2007 ftunivtroemsoe https://doi.org/10.1186/bcr1782 2024-05-07T08:41:49Z Background: Recent cohort studies have suggested an increased risk of breast cancer with long duration of smoking, and with smoking initiation before first birth. Cigarette smoking may have both carcinogenic effects and antiestrogenic effects on the breast tissue. We decided to examine the relationship between different measures of smoking exposure and mammographic density. Methods: Lifetime smoking history was collected through interview and questionnaires among 907 postmenopausal participants in the Tromsø Mammography and Breast Cancer study. The mammograms were obtained from the governmental Norwegian Breast Cancer Screening Program. Mammograms were classified according to the percentage and absolute mammographic densities using a previously validated computerassisted method. Results:Sixty-five percent of the women reported having ever smoked cigarettes, while 34% were current smokers. After adjustment for age, age at first birth, parity, age at menopause, postmenopausal hormone therapy use, and body mass index, smoking was inversely associated with both measures of mammographic density (both trends P < 0.01). Both current smokers and former smokers had significantly lower adjusted mean percentage mammographic density compared with never smokers (P = 0.003 and P = 0.006, respectively). An inverse dose–response relationship with mammographic density was found between both the number of cigarettes and the number of pack-years smoked among current smokers. Current smokers who smoked 11 cigarettes or more daily had a 3.7% absolute (36% relative difference) lower percentage mammographic density compared with current smokers who smoked seven cigarettes or less daily (P = 0.008). When former smokers were stratified according to time since smoking cessation, we found that women who had stopped smoking less than 24 years ago had a significantly lower mean percentage mammographic density compared with never smokers (P < 0.001). Conclusion: We found modest inverse dose–response associations between numbers of ... Article in Journal/Newspaper Tromsø University of Tromsø: Munin Open Research Archive Tromsø Breast Cancer Research 9 5 |
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University of Tromsø: Munin Open Research Archive |
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English |
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VDP::Medical disciplines: 700::Clinical medical disciplines: 750::Oncology: 762 |
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VDP::Medical disciplines: 700::Clinical medical disciplines: 750::Oncology: 762 Bremnes, Yngve Bjurstam, Nils Ursin, Giske Gram, Inger Torhild Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
topic_facet |
VDP::Medical disciplines: 700::Clinical medical disciplines: 750::Oncology: 762 |
description |
Background: Recent cohort studies have suggested an increased risk of breast cancer with long duration of smoking, and with smoking initiation before first birth. Cigarette smoking may have both carcinogenic effects and antiestrogenic effects on the breast tissue. We decided to examine the relationship between different measures of smoking exposure and mammographic density. Methods: Lifetime smoking history was collected through interview and questionnaires among 907 postmenopausal participants in the Tromsø Mammography and Breast Cancer study. The mammograms were obtained from the governmental Norwegian Breast Cancer Screening Program. Mammograms were classified according to the percentage and absolute mammographic densities using a previously validated computerassisted method. Results:Sixty-five percent of the women reported having ever smoked cigarettes, while 34% were current smokers. After adjustment for age, age at first birth, parity, age at menopause, postmenopausal hormone therapy use, and body mass index, smoking was inversely associated with both measures of mammographic density (both trends P < 0.01). Both current smokers and former smokers had significantly lower adjusted mean percentage mammographic density compared with never smokers (P = 0.003 and P = 0.006, respectively). An inverse dose–response relationship with mammographic density was found between both the number of cigarettes and the number of pack-years smoked among current smokers. Current smokers who smoked 11 cigarettes or more daily had a 3.7% absolute (36% relative difference) lower percentage mammographic density compared with current smokers who smoked seven cigarettes or less daily (P = 0.008). When former smokers were stratified according to time since smoking cessation, we found that women who had stopped smoking less than 24 years ago had a significantly lower mean percentage mammographic density compared with never smokers (P < 0.001). Conclusion: We found modest inverse dose–response associations between numbers of ... |
format |
Article in Journal/Newspaper |
author |
Bremnes, Yngve Bjurstam, Nils Ursin, Giske Gram, Inger Torhild |
author_facet |
Bremnes, Yngve Bjurstam, Nils Ursin, Giske Gram, Inger Torhild |
author_sort |
Bremnes, Yngve |
title |
Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
title_short |
Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
title_full |
Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
title_fullStr |
Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
title_full_unstemmed |
Different measures of smoking exposure and mammographic density in postmenopausal Norwegian women : a cross-sectional study |
title_sort |
different measures of smoking exposure and mammographic density in postmenopausal norwegian women : a cross-sectional study |
publisher |
BioMed Central |
publishDate |
2007 |
url |
https://hdl.handle.net/10037/1246 https://doi.org/10.1186/bcr1782 |
geographic |
Tromsø |
geographic_facet |
Tromsø |
genre |
Tromsø |
genre_facet |
Tromsø |
op_relation |
Breast Cancer Research 9(2007)no 5, R73 doi:10.1186/bcr1782 1465-5411 https://hdl.handle.net/10037/1246 URN:NBN:no-uit_munin_1062 |
op_rights |
openAccess |
op_doi |
https://doi.org/10.1186/bcr1782 |
container_title |
Breast Cancer Research |
container_volume |
9 |
container_issue |
5 |
_version_ |
1800739496618098688 |