National School of Occupational Medicine as reference in the formation of medicine and nursing labour

Hablar de los últimos seis años de la Escuela Nacional de Medicina de Trabajo (ENMT), supone hablar de un periodo de trabajo para afrontar una adaptación de la actividad y carta de servicios de la Escuela a las nuevas necesidades en el ejercicio de la de Medicina y Enfermería del Trabajo. El conjunto de esfuerzos desarrollados por el equipo de la ENMT ha estado dirigido a llevar la Escuela al centro y al puesto de trabajo del profesional de la Medicina y Enfermería, invirtiendo las anteriores coordenadas bajo las cuales era el profesional el que se debía acercar a la Escuela. Los pilares en los que se ha basado la política de desarrollo de la Escuela Nacional de Medicina del Trabajo han sido: la innovación tecnológica, el fortalecimiento de la oferta docente y las alianzas con los diferentes actores comprometidos con el progreso en salud de la sociedad del trabajo de nuestro país El desarrollo de la ENMT se ha realizado en el marco de la Sociedad de la Información, siendo la utilización de las TICs el mejor vehículo para llevar el conocimiento científico y la formación al puesto de trabajo del profesional sanitario.S

Structure and content of communication and writing scientific articles

[ES]La comunicación científica es parte del proceso investigador y representa unos de los retornos que recibe la Sociedad del investigador. La comunicación científica se somete a una estructura internacionalmente aceptada: Introducción, Material y Métodos, Resultados, Conclusiones y Discusión, en la que cada apartado tiene una finalidad y una intención. Tras haber realizado una revisión de las publicaciones y guías más recientes sobre comunicación científica en salud se ha sintetizado las recomendaciones más relevantes con la intención de orientar a los autores noveles en la redacción de sus primeras publicaciones. Scientific communication is part of the research process and represents one of the returns that Society receives from researchers. [EN] Scientific communication is under an internationally accepted structure: Introduction, Material and Methods, Results, Conclusions and Discussion, each item have a concrete purpose and intention. After has conducted a review of the most recent publications and guidelines on health science communication we have synthesized the most relevant recommendations in order to guide early scientific authors in write his scientific papers.S

Effects of noise exposure in working places on quality of life and performance

[ES] Objetivos: La exposición laboral a ruido origina efectos sobre la salud de carácter no auditivo. El objetivo de este estudio es estimar la asociación entre exposición a ruido en entornos laborales y la aparición de alteraciones en la conducta, rendimiento y síntomas psicosomáticos. Metodología: Estudio de prevalencia a partir de datos de la VI Encuesta Nacional de Condiciones de Trabajo analizando como variable independiente la exposición a ruido y como variables dependientes los "síntomas que manifiesta el trabajador" tratados de forma individual o por grupo de síntomas según su naturaleza: conductual, psicosomáticos y rendimiento. La asociación entre exposición y efecto se analizó mediante la prueba de X2 y se calculó el OR de prevalencias ajustado por ritmo de trabajo (IC95%) para medir la asociación entre "exposición a ruido" y grupos de síntomas de forma cruda en el conjunto de la población y de forma estratificada por ramas de actividad. Resultados: El 36,5% de la población trabajadora está expuesta a ruido en su puesto de trabajo. Se observa una mayor prevalencia de los grupos de síntomas conductuales, psicosomáticos y de rendimiento (p<0,001) entre los trabajadores expuestos a ruido frente a no expuestos. La rama de Actividades Sanitarias presenta los mayores valores de OR para el grupo de síntomas conductuales (OR=2,53 [1,71-3,75]) y de rendimiento (OR=2,26, [1,43-3,56]) y la Industria Química presenta el mayor grado de asociación entre exposición a ruido y síntomas psicosomáticos (OR=5,37, [1,13-25,55]). Conclusiones: Se observa una asociación estadísticamente significativa entre exposición a ruido y alteraciones de conducta, rendimiento y síntomas psicosomáticos en la población trabajadora española.[EN] Aims: Occupational noise exposure could produce extra-auditory effects. The purpose of this study was to investigate whether occupational noise exposure can influence human behaviour, performance and development of psychosomatic symptoms. Methodology: Cross-sectional study, from the Data-base of Spanish VI National Survey on Working Conditions, "noise exposure" has been analyzed as independent variable and: "symptoms self-reportered by workers" as effect variable, considering them independently or grouped variables in behavioural, psychosomatic and performance symptoms. The relationship between exposure and effect was analyzed by X2 test. Prevalence adjusted Odds Ratio by work rhythm (95% CI), were estimated to measure the association between perceived noise annoyance and grouped symptoms in the population and in the different branches of activity. Results: 36.5% of the working population is exposed to noise in their workplace. There is a higher prevalence of behavioural symptoms group, psychosomatic and performance (p <0.001) among workers exposed to noise compared to unexposed. Health Care Sector reported the highest risk for behavioural (OR=2,53 [1,71-3,75]) and performance symptoms(OR=2,26, [1,43-3,56]) . Chemical Industry had a prevalence ratio between noise and psychosomatic symptoms of (OR=5,37 [1,13-25,55]). Conclusions: Our results found and statistic significant association between noise annoyance exposure and behavioural, performance and development of psychosomatic symptoms in the Spanish working population.S

Systematic review and evidence on occupational noise exposure and extra-auditory effects of no cardiovascular nature

[ES] Trabajo de revisión que tienen como objetivo conocer el nivel de evidencia existente sobre los efectos extra-auditivos de la exposición profesional al ruido relacionados con: alteraciones bioquímicas, efectos neuro-piscológicos, salud reproductiva y accidentes de trabajo mediante el análisis sistemático de la producción científica publicada entre 1995 y 2008. La búsqueda de las referencias bibliográficas se realizó mediante términos "Major Topic"y "MeSH" para MEDLINE y términos "Decriptors" para OSH update. Se recuperaron un total de 370 referencias y se incluyeron en la revisión todos los estudios experimentales, estudios de cohortes y estudios casos control y aquellos estudios trasversales que cumplieron al menos con cinco de los nueve criterios que la declaración STROBE establece para los estudios observacionales. Fueron seleccionados para su revisión a texto completo un total de 35 artículos: 14 estudios experimentales, 2 estudios de cohortes, 6 estudios casos control, 12 estudios transversales y 1 estudio de validación. La asignación del nivel de evidencia se realizó de acuerdo a los criterios SIGN. La selección y revisión de los artículos se realizó mediante revisión por pares, los casos de discrepancia entre pares se resolvió mediante consenso. Encontramos un alto nivel de evidencia (1+) para influencia de la exposición profesional al ruido sobre el incremento de la secreción de cortisol y noradrenalina, fatiga y disminución del rendimiento, funciones cognitivas y memoria, disminución en la calidad del sueño, estrés e irritabilidad y percepción de malestar. Con un nivel de evidencia 2++ se relacionó la exposición profesional al ruido con la accidentalidad laboral. No encontramos unos resultados concluyentes para la determinación de la relación entre exposición profesional al ruido sobre la salud reproductiva. Existe una diversidad en los métodos utilizados para la evaluación de la exposición profesional al ruido, empleándose tanto métodos de medición cuantitativos y métodos cualitativos de percepción subjetiva. Nuestros resultados son coincidentes con las revisiones realizadas anteriormente por Smith AP y cols (1991) y Butler MP y cols (1999). Review aimed at ascertaining the level of evidence on non-auditory effects related with occupational exposure to noise concerning: biochemical, neuro- psychology effects, reproductive health and accidents at work through a systematic analysis of the scientific literature published between 1995 and 2008. The search for references was conducted using terms "Major Topic" and "MeSH" terms for MEDLINE and "Decriptors" for OSH update. We retrieved a total of 370 references, were included in the review all experimental studies, cohort studies and case control studies and those cross-sectional studies that had at least five of the nine criteria that the STROBE Statement provides for observational studies. Were selected for full text review a total of 35 studies: 14 experimental studies, 2 cohort studies, 6 case control studies, 12 cross-sectional studies and 1 validation study. The assignment of the level of evidence was performed according to SIGN criteria. The selection and review of articles was done by peer review, cases of disagreement between pairs was resolved by consensus. We found a high level of evidence (1+) about the influence of occupational noise exposure and the increased secretion of cortisol and norepinephrine, fatigue and decreased performance, cognitive function and memory, decreased quality of sleep, stress and irritability annoyance. A level of evidence 2++ was identify for occupational noise exposure and work accidents. We found no conclusive results in determine the relationship between occupational exposure to noise on reproductive health. There is diversity in the methods used for assessing occupational exposure to noise, using both quantitative measurement methods and qualitative methods of subjective perception. Our results are consistent with those previously reported by Smith AP et alt (1991) and Butler MP et al (1999). [EN] Review aimed at ascertaining the level of evidence on non-auditory effects related with occupational exposure to noise concerning: biochemical, neuro- psychology effects, reproductive health and accidents at work through a systematic analysis of the scientific literature published between 1995 and 2008. The search for references was conducted using terms “Major Topic” and “MeSH” terms for MEDLINE and “Decriptors” for OSH update. We retrieved a total of 370 references, were included in the review all experimental studies, cohort studies and case control studies and those cross-sectional studies that had at least five of the nine criteria that the STROBE Statement provides for observational studies. Were selected for full text review a total of 35 studies: 14 experimental studies, 2 cohort studies, 6 case control studies, 12 cross-sectional studies and 1 validation study. The assignment of the level of evidence was performed according to SIGN criteria. The selection and review of articles was done by peer review, cases of disagreement between pairs was resolved by consensus. We found a high level of evidence (1+) about the influence of occupational noise exposure and the increased secretion of cortisol and norepinephrine, fatigue and decreased performance, cognitive function memory, decreased quality of sleep, stress and irritability annoyance. A level of evidence 2++ was identify for occupational noise exposure and work accidents. We found no conclusive results in determine the relationship between occupational exposure to noise on reproductive health. There is diversity in the methods used for assessing occupational exposure to noise, using both quantitative measurement methods and qualitative methods of subjective perception. Our results are consistent with those previously reported by Smith AP et alt (1991) and Butler MP et al (1999).S

Systematic review and evidence on occupational noise exposure and extra-auditory effects of cardiovascular nature

[ES] Trabajo de revisión que tiene como objetivo conocer el nivel de evidencia existente sobre los efectos cardiovasculares debidos a la exposición profesional al ruido, mediante el análisis sistemático de la producción científica publicada entre 1995 y 2008. La búsqueda de las referencias bibliográficas se realizó mediante términos "Major Topic" y "MeSH" para MEDLINE y términos "Decriptors" para OSH update. Se recuperaron un total de 236 referencias y se incluyeron en la revisión todos los estudios experimentales, estudios de cohortes y estudios casos control y aquellos estudios trasversales que cumplieron, al menos, con cinco de los nueve criterios que la declaración STROBE establece para los estudios observacionales. Fueron seleccionados para su revisión a texto completo un total de 23 artículos: 12 estudios transversales, 7 estudios de cohortes, dos estudios casos control, 1 meta-análisis y 1 estudio experimental. La asignación del nivel de evidencia se realizó de acuerdo a los criterios SIGN. La selección y revisión de los artículos se realizó mediante revisión por pares, los casos de discrepancia entre pares se resolvió mediante consenso. En relación con los efectos cardiovasculares de la exposición laboral a ruido, nuestra revisión encuentra un mayor nivel de evidencia (1++) para el incremento de la tensión arterial e incremento de la frecuencia cardiaca. Estudios con nivel de evidencia 2++ muestran resultados en esa misma dirección. La enfermedad isquémica, infarto agudo de miocardio y coronariopatía muestran un nivel de evidencia 2++. La alteraciones metabólicas de lípidos y alteraciones de parámetros vasculares disponen de un nivel bajo de evidencia3. El control del ruido en entornos laborales es un factor de prevención del riesgo cardio-vascular. HTA, riesgo coronario y otras enfermedades cardiovasculares deben considerarse en los protocolos de vigilancia médica específica de los trabajadores expuestos a ruido. Review aimed to identify the level of scientific evidence about the relationship between cardiovascular diseases and occupational noise exposure, by a systematic analysis of the scientific literature published between 1995 and 2008. "Major Topic" and "MeSH" terms for MEDLINE and "Decriptors" for OSH update was used for the search of references. We retrieved a total of 236 references. Experimental studies, cohort studies and case control studies were all included in the review and those cross-sectional studies with at least five of the nine criteria from the STROBE declaration provides for observational studies. 23 articles were selected for full text review: 12 cross-sectional studies, 7 cohort studies, two case control studies, 1 meta-analysis and 1 experimental study. The evidence level was performed according to SIGN criteria. The selection and review of articles was done by peer review, cases of disagreement between pairs was resolved by consensus. Our review found a higher level of evidence (1++) for increasing blood pressure and increased heart rate and occupational noise exposure. Studies with a level of evidence 2++ show results in the same direction. Ischemic heart disease, myocardial infarction and coronary diseases show a level of evidence 2++. Metabolic changes of lipid parameters and vascular abnormalities have a low level of evidence3. Noise control in working environments is a measure for cardiovascular risk prevention. Hypertension, coronary risk and other cardiovascular diseases should be considered in medical surveillance practice of workers exposed to noise.[EN] Review aimed to identify the level of scientific evidence about the relationship between cardiovascular diseases and occupational noise exposure, by a systematic analysis of the scientific literature published between 1995 and 2008. “Major Topic” and “MeSH” terms for MEDLINE and “Decriptors” for OSH update was used for the search of references. We retrieved a total of 236 references. Experimental studies, cohort studies and case control studies were all included in the review and those cross-sectional studies with at least five of the nine criteria from the STROBE declaration provides for observational studies. 23 articles were selected for full text review: 12 cross-sectional studies, 7 cohort studies, two case control studies, 1 meta-analysis and 1 experimental study. The evidence level was performed according to SIGN criteria. The selection and review of articles was done by peer review, cases of disagreement between pairs was resolved by consensus. Our review found a higher level of evidence (1++) for increasing blood pressure and increased heart rate and occupational noise exposure. Studies with a level of evidence 2++ show results in the same direction. Ischemic heart disease, myocardial infarction and coronary diseases show a level of evidence 2++. Metabolic changes of lipid parameters and vascular abnormalities have a low level of evidence 3. Noise control in working environments is a measure for cardiovascular risk prevention. Hypertension, coronary risk and other cardiovascular diseases should be considered in medical surveillance practice of workers exposed to noise.S

Revisión sobre la evidencia de la relación entre exposición profesional al ruido y efectos extrauditivos no cardio-vasculares Systematic review and evidence on occupational noise exposure and extra-auditory effects of no cardiovascular nature

Trabajo de revisión que tienen como objetivo conocer el nivel de evidencia existente sobre los efectos extra-auditivos de la exposición profesional al ruido relacionados con: alteraciones bioquímicas, efectos neuro-piscológicos, salud reproductiva y accidentes de trabajo mediante el análisis sistemático de la producción científica publicada entre 1995 y 2008. La búsqueda de las referencias bibliográficas se realizó mediante términos "Major Topic"y "MeSH" para MEDLINE y términos "Decriptors" para OSH update. Se recuperaron un total de 370 referencias y se incluyeron en la revisión todos los estudios experimentales, estudios de cohortes y estudios casos control y aquellos estudios trasversales que cumplieron al menos con cinco de los nueve criterios que la declaración STROBE establece para los estudios observacionales. Fueron seleccionados para su revisión a texto completo un total de 35 artículos: 14 estudios experimentales, 2 estudios de cohortes, 6 estudios casos control, 12 estudios transversales y 1 estudio de validación. La asignación del nivel de evidencia se realizó de acuerdo a los criterios SIGN. La selección y revisión de los artículos se realizó mediante revisión por pares, los casos de discrepancia entre pares se resolvió mediante consenso. Encontramos un alto nivel de evidencia (1+) para influencia de la exposición profesional al ruido sobre el incremento de la secreción de cortisol y noradrenalina, fatiga y disminución del rendimiento, funciones cognitivas y memoria, disminución en la calidad del sueño, estrés e irritabilidad y percepción de malestar. Con un nivel de evidencia 2++ se relacionó la exposición profesional al ruido con la accidentalidad laboral. No encontramos unos resultados concluyentes para la determinación de la relación entre exposición profesional al ruido sobre la salud reproductiva. Existe una diversidad en los métodos utilizados para la evaluación de la exposición profesional al ruido, empleándose tanto métodos de medición cuantitativos y métodos cualitativos de percepción subjetiva. Nuestros resultados son coincidentes con las revisiones realizadas anteriormente por Smith AP y cols (1991) y Butler MP y cols (1999).Review aimed at ascertaining the level of evidence on non-auditory effects related with occupational exposure to noise concerning: biochemical, neuro- psychology effects, reproductive health and accidents at work through a systematic analysis of the scientific literature published between 1995 and 2008. The search for references was conducted using terms "Major Topic" and "MeSH" terms for MEDLINE and "Decriptors" for OSH update. We retrieved a total of 370 references, were included in the review all experimental studies, cohort studies and case control studies and those cross-sectional studies that had at least five of the nine criteria that the STROBE Statement provides for observational studies. Were selected for full text review a total of 35 studies: 14 experimental studies, 2 cohort studies, 6 case control studies, 12 cross-sectional studies and 1 validation study. The assignment of the level of evidence was performed according to SIGN criteria. The selection and review of articles was done by peer review, cases of disagreement between pairs was resolved by consensus. We found a high level of evidence (1+) about the influence of occupational noise exposure and the increased secretion of cortisol and norepinephrine, fatigue and decreased performance, cognitive function and memory, decreased quality of sleep, stress and irritability annoyance. A level of evidence 2++ was identify for occupational noise exposure and work accidents. We found no conclusive results in determine the relationship between occupational exposure to noise on reproductive health. There is diversity in the methods used for assessing occupational exposure to noise, using both quantitative measurement methods and qualitative methods of subjective perception. Our results are consistent with those previously reported by Smith AP et alt (1991) and Butler MP et al (1999)

Occupational exposures and mammographic density in Spanish women

[EN] Objectives The association between occupational exposures and mammographic density (MD), a marker of breast cancer risk, has not been previously explored. Our objective was to investigate the influence of occupational exposure to chemical, physical and microbiological agents on MD in adult women. Methods This is a population-based cross-sectional study based on 1476 female workers aged 45-65 years from seven Spanish breast cancer screening programmes. Occupational history was surveyed by trained staff. Exposure to occupational agents was assessed using the Spanish job-exposure matrix MatEmESp. Percentage of MD was measured by two radiologists using a semiautomatic computer tool. The association was estimated using mixed log-linear regression models adjusting for age, education, body mass index, menopausal status, parity, smoking, alcohol intake, type of mammography, family history of breast cancer and hormonal therapy use, and including screening centre and professional reader as random effects terms. Results Although no association was found with most of the agents, women occupationally exposed to perchloroethylene (e(beta)=1.51; 95% CI 1.04 to 2.19), ionising radiation (e(beta)=1.23; 95% CI 0.99 to 1.52) and mould spores (e(beta)=1.44; 95% CI 1.01 to 2.04) tended to have higher MD. The percentage of density increased 12% for every 5 years exposure to perchloroethylene or mould spores, 11% for every 5 years exposure to aliphatic/alicyclic hydrocarbon solvents and 3% for each 5 years exposure to ionising radiation. Conclusions Exposure to perchloroethylene, ionising radiation, mould spores or aliphatic/alicyclic hydrocarbon solvents in occupational settings could be associated with higher MD. Further studies are needed to clarify the accuracy and the reasons for these findings.This study was funded by the Spanish Ministry of Economy and Competitiveness - Carlos II Institute of Health (ISCI) (AESI PI15CI/00013); the Scientific Foundation of the Spanish Association Against Cancer (Fundacion Cientifica de la Asociacion Espanola Contra el Cancer (AEC) - EVP-1178/14); the Spanish Public Health Research Fund (FIS PI060386 & PS09/0790); the collaboration agreement between Astra-Zeneca and the ISCI (EPY1306/06) and a grant from the Spanish Federation of Breast Cancer Patients (FECMA 485 EPY 1170-10).Lope, V.; García-Pérez, J.; Pérez-Gómez, B.; Pedraza-Flechas, AM.; Alguacil, J.; González-Galarzo, MC.; Alba, MA.... (2018). Occupational exposures and mammographic density in Spanish women. Journal of Occupational and Environmental Medicine. 75(2):124-131. https://doi.org/10.1136/oemed-2017-104580S124131752Boyd, N. F., Guo, H., Martin, L. J., Sun, L., Stone, J., Fishell, E., … Yaffe, M. J. (2007). Mammographic Density and the Risk and Detection of Breast Cancer. New England Journal of Medicine, 356(3), 227-236. doi:10.1056/nejmoa062790McCormack, V. A. (2006). Breast Density and Parenchymal Patterns as Markers of Breast Cancer Risk: A Meta-analysis. Cancer Epidemiology Biomarkers & Prevention, 15(6), 1159-1169. doi:10.1158/1055-9965.epi-06-0034Assi, V., Warwick, J., Cuzick, J., & Duffy, S. W. (2011). Clinical and epidemiological issues in mammographic density. Nature Reviews Clinical Oncology, 9(1), 33-40. doi:10.1038/nrclinonc.2011.173Ursin, G., Lillie, E. O., Lee, E., Cockburn, M., Schork, N. J., Cozen, W., … Mack, T. (2009). The Relative Importance of Genetics and Environment on Mammographic Density. Cancer Epidemiology Biomarkers & Prevention, 18(1), 102-112. doi:10.1158/1055-9965.epi-07-2857Ironside, A. J., & Jones, J. L. (2016). Stromal characteristics may hold the key to mammographic density: the evidence to date. Oncotarget, 7(21), 31550-31562. doi:10.18632/oncotarget.6912Kogevinas M , van der Haar R , Fernández F , et al . Sistema de Información sobre exposición ocupacional a carcinógenos en España en el año 2004, 2006.List of Classifications by cancer sites with sufficient or limited evidence in humans. Monographs on the Evaluation of Carcinogenic Risks to Humans. vol 1 to 118. Lyon, France: International Agency for Research on Cancer, 2016. http://monographs.iarc.fr/ENG/Classification/Table4.pdfRudel, R. A., Attfield, K. R., Schifano, J. N., & Brody, J. G. (2007). Chemicals causing mammary gland tumors in animals signal new directions for epidemiology, chemicals testing, and risk assessment for breast cancer prevention. Cancer, 109(S12), 2635-2666. doi:10.1002/cncr.22653Knower, K. C., To, S. Q., Leung, Y.-K., Ho, S.-M., & Clyne, C. D. (2014). Endocrine disruption of the epigenome: a breast cancer link. Endocrine-Related Cancer, 21(2), T33-T55. doi:10.1530/erc-13-0513Pollán, M., Lope, V., Miranda-García, J., García, M., Casanova, F., … Ruiz-Perales, F. (2012). Adult weight gain, fat distribution and mammographic density in Spanish pre- and post-menopausal women (DDM-Spain). Breast Cancer Research and Treatment, 134(2), 823-838. doi:10.1007/s10549-012-2108-3Pollán M , Llobet R , Miranda-García J , et al . Validation of DM-Scan, a computer-assisted tool to assess mammographic density in full-field digital mammograms. Springerplus 2013;2:242.doi:10.1186/2193-1801-2-242Instituto Nacional de Estadística. National classification of occupations 1994 (CNO-94): INEbase, 2016. http://www.ine.es/jaxi/menu.do?type=pcaxis&path=/t40/cno94/&file=inebase&L=1International Agency for Research on Cancer. Trichloroethylene, tetrachloroethylene, and some other chlorinated agents. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. 106. Lyon, France, 2014. https://monographs.iarc.fr/ENG/Monographs/vol106/mono106.pdf.Ministerio de Agricultura y Pesca, Alimentación y Medio Ambiente. Análisis por actividades emisoras de la nomenclatura SNAP, vol 2. InventariosNacionales de Emisiones a la Atmósfera 1990-2012, 2014. http://www.mapama.gob.es/es/calidad-y-evaluacion-ambiental/temas/sistema-espanol-de-inventario-sei-/06_Uso_de_Disolventes_y_Otros_Productos_-_VNC_tcm7-219786.pdfThe Endocrine Disruption Exchange. TEDX list of potential endocrine disruptors, 2017. https://endocrinedisruption.org/interactive-tools/tedx-list-of-potential-endocrine-disruptors/search-the-tedx-list.International Agency for Research on Cancer. Painting, firefighting, and shiftwork. IARC monographs on the evaluation of carcinogenic risks to humans. 98. Lyon, France, 2010. https://monographs.iarc.fr/ENG/Monographs/vol98/mono98.pd

Occupation and mammographic density: A population-based study (DDM-Occup)

INTRODUCTION: High mammographic density is one of the main risk factors for breast cancer. Although several occupations have been associated with breast cancer, there are no previous occupational studies exploring the association with mammographic density. Our objective was to identify occupations associated with high mammographic density in Spanish female workers. METHODS: We conducted a population-based cross-sectional study of occupational determinants of high mammographic density in Spain, based on 1476 women, aged 45-68 years, recruited from seven screening centers within the Spanish Breast Cancer Screening Program network. Reproductive, family, personal, and occupational history data were collected. The latest occupation of each woman was collected and coded according to the 1994 National Classification of Occupations. Mammographic density was assessed from the cranio-caudal mammogram of the left breast using a semi-automated computer-assisted tool. Association between mammographic density and occupation was evaluated by using mixed linear regression models, using log-transformed percentage of mammographic density as dependent variable. Models were adjusted for age, body mass index, menopausal status, parity, smoking, alcohol intake, educational level, type of mammography, first-degree relative with breast cancer, and hormonal replacement therapy use. Screening center and professional reader were included as random effects terms. RESULTS: Mammographic density was higher, although non-statistically significant, among secondary school teachers (eβ = 1.41; 95%CI = 0.98-2.03) and nurses (eβ = 1.23; 95%CI = 0.96-1.59), whereas workers engaged in the care of people (eβ = 0.81; 95%CI = 0.66-1.00) and housewives (eβ = 0.87; 95%CI = 0.79-0.95) showed an inverse association with mammographic density. A positive trend for every 5 years working as secondary school teachers was also detected (p-value = 0.035). CONCLUSIONS: Nurses and secondary school teachers were the occupations with the highest mammographic density in our study, showing the latter a positive trend with duration of employment. Future studies are necessary to confirm if these results are due to chance or are the result of a true association whose causal hypothesis is, for the moment, unknown.This study was funded by Strategic Action of Intramural Health (Acción Estratégica de Salud Intramural - AESI PI15CIII/00013); the Scientific Foundation of the Spanish Association Against Cancer (Fundación Científica de la Asociación Española Contra el Cáncer (AECC) – EVP-1178/14); the Research Grant FIS PI060386 & PS09/790 from Spain’s Health Research Fund (Fondo de Investigación Sanitaria); the EPY 1306/06 Collaboration Agreement between Astra-Zeneca and the Carlos III Institute of Health; and a grant from the Spanish Federation of Breast Cancer patients (FECMA 485 EPY 1170-10).S