title: Breast cancer risk and night shift work in a case-control study in a Spanish population.
abstract: Epidemiologic and animal data indicate that night shift work might increase the risk for breast cancer. We evaluated the association of night work with different clinical types of breast cancer in a population based case-control study (MCC-Spain study) taking into account chronotype, an individual characteristic that may relate to night shift work adaptation. Lifetime occupational history was assessed by face-to-face interviews and shift work information was available for 1708 breast cancer cases and 1778 population controls from 10 Spanish regions, enrolled from 2008 to 2013. We evaluated three shift work domains, including shift work type (permanent vs rotating), lifetime cumulative duration and frequency. We estimated odds ratios (OR) for night work compared to day work using unconditional logistic regression models adjusting for confounders. Having ever worked permanent or rotating night shift was associated with an increased risk for breast cancer compared to day workers [odds ratio (OR) 1.18; 95 % CI 0.97, 1.43]. Chronotype was differentially associated with breast cancer depending on the duration of night shift work. Risk was higher in women with invasive tumors (OR 1.23; 95 % CI 1.00, 1.51) and for estrogen and progestagen positive tumors among premenopausal women (OR 1.44; 95 % CI 1.05, 1.99). Having ever performed night shift was associated with a small increased risk for breast cancer and especially in subgroups of women with particular hormone related characteristics.
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Doctor Aiguader, 88, 08003, Barcelona, Spain.|IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Universitat Pompeu Fabra (UPF), Barcelona, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Papantoniou
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Doctor Aiguader, 88, 08003, Barcelona, Spain.|IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Universitat Pompeu Fabra (UPF), Barcelona, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Castaño-Vinyals
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Doctor Aiguader, 88, 08003, Barcelona, Spain.|IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|Universitat Pompeu Fabra (UPF), Barcelona, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Espinosa
authors.affiliation: Environmental and Cancer Epidemiology Area, National Center of Epidemiology, Carlos III Health Institute, Madrid, Spain.|Cancer Epidemiology Research Group, Oncology and Hematology Area, IIS Puerta de Hierro, Madrid, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Nuria
authors.initials: N
authors.lastname: Aragonés
authors.affiliation: Environmental and Cancer Epidemiology Area, National Center of Epidemiology, Carlos III Health Institute, Madrid, Spain.|Cancer Epidemiology Research Group, Oncology and Hematology Area, IIS Puerta de Hierro, Madrid, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Pérez-Gómez
authors.affiliation: Instituto de Salud Publica de Navarra, Pamplona, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Ardanaz
authors.affiliation: Public Health Division of Gipuzkoa-BIODONOSTIA, Basque Regional Health Department, San Sebastian, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Jone Miren
authors.initials: JM
authors.lastname: Altzibar
authors.affiliation: Universidad de León, León, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Vicente Martin
authors.initials: VM
authors.lastname: Sanchez
authors.affiliation: University of Cantabria, Santander, Spain.|IDIVAL, Santander, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Inés
authors.initials: I
authors.lastname: Gómez-Acebo
authors.affiliation: University of Cantabria, Santander, Spain.|IDIVAL, Santander, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Llorca
authors.affiliation: Centro de Investigación en Salud y Medio Ambiente (CYSMA), Universidad de Huelva, Huelva, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Muñoz
authors.affiliation: IUOPA, Universidad de Oviedo, Asturias, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardón
authors.affiliation: Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunidad Valenciana (FISABIO), Valencia, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Rosana
authors.initials: R
authors.lastname: Peiró
authors.affiliation: Epidemiology Unit and Girona Cancer Registry (Oncology Coordination Plan), Department of Health, Autonomous Government of Catalonia, Catalan Institute of Oncology, Girona Biomedical Research Institute, Girona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Marcos-Gragera
authors.affiliation: Environmental and Cancer Epidemiology Area, National Center of Epidemiology, Carlos III Health Institute, Madrid, Spain.|Cancer Epidemiology Research Group, Oncology and Hematology Area, IIS Puerta de Hierro, Madrid, Spain.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Pollan
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Doctor Aiguader, 88, 08003, Barcelona, Spain. kogevinas@creal.cat.|IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain. kogevinas@creal.cat.|Universitat Pompeu Fabra (UPF), Barcelona, Spain. kogevinas@creal.cat.|CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain. kogevinas@creal.cat.|National School of Public Health, Athens, Greece. kogevinas@creal.cat.
authors.forename: Manolis
authors.initials: M
authors.lastname: Kogevinas
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors; D000073577:Shift Work Schedule / Q000009:adverse effects*; D013030:Spain / Q000453:epidemiology; D014940:Work Schedule Tolerance
keywords: Breast cancer; Circadian disruption; Night shift