34 research outputs found
International Consortium on Mammographic Density:methodology and population diversity captured across 22 countries
Mammographic density (MD) is a quantitative trait, measurable in all women, and is among the strongest markers of breast cancer risk. The population-based epidemiology of MD has revealed genetic, lifestyle and societal/environmental determinants, but studies have largely been conducted in women with similar westernized lifestyles living in countries with high breast cancer incidence rates. To benefit from the heterogeneity in risk factors and their combinations worldwide, we created an International Consortium on Mammographic Density (ICMD) to pool individual-level epidemiological and MD data from general population studies worldwide. ICMD aims to characterize determinants of MD more precisely, and to evaluate whether they are consistent across populations worldwide. We included 11755 women, from 27 studies in 22 countries, on whom individual-level risk factor data were pooled and original mammographic images were re-read for ICMD to obtain standardized comparable MD data. In the present article, we present (i) the rationale for this consortium; (ii) characteristics of the studies and women included; and (iii) study methodology to obtain comparable MD data from original re-read films. We also highlight the risk factor heterogeneity captured by such an effort and, thus, the unique insight the pooled study promises to offer through wider exposure ranges, different confounding structures and enhanced power for sub-group analyses
Mammographic density and ageing:A collaborative pooled analysis of cross-sectional data from 22 countries worldwide
BACKGROUND: Mammographic density (MD) is one of the strongest breast cancer risk factors. Its age-related characteristics have been studied in women in western countries, but whether these associations apply to women worldwide is not known. METHODS AND FINDINGS: We examined cross-sectional differences in MD by age and menopausal status in over 11,000 breast-cancer-free women aged 35-85 years, from 40 ethnicity- and location-specific population groups across 22 countries in the International Consortium on Mammographic Density (ICMD). MD was read centrally using a quantitative method (Cumulus) and its square-root metrics were analysed using meta-analysis of group-level estimates and linear regression models of pooled data, adjusted for body mass index, reproductive factors, mammogram view, image type, and reader. In all, 4,534 women were premenopausal, and 6,481 postmenopausal, at the time of mammography. A large age-adjusted difference in percent MD (PD) between post- and premenopausal women was apparent (-0.46 cm [95% CI: -0.53, -0.39]) and appeared greater in women with lower breast cancer risk profiles; variation across population groups due to heterogeneity (I2) was 16.5%. Among premenopausal women, the √PD difference per 10-year increase in age was -0.24 cm (95% CI: -0.34, -0.14; I2 = 30%), reflecting a compositional change (lower dense area and higher non-dense area, with no difference in breast area). In postmenopausal women, the corresponding difference in √PD (-0.38 cm [95% CI: -0.44, -0.33]; I2 = 30%) was additionally driven by increasing breast area. The study is limited by different mammography systems and its cross-sectional rather than longitudinal nature. CONCLUSIONS: Declines in MD with increasing age are present premenopausally, continue postmenopausally, and are most pronounced over the menopausal transition. These effects were highly consistent across diverse groups of women worldwide, suggesting that they result from an intrinsic biological, likely hormonal, mechanism common to women. If cumulative breast density is a key determinant of breast cancer risk, younger ages may be the more critical periods for lifestyle modifications aimed at breast density and breast cancer risk reduction
Impact of common cardio-metabolic risk factors on fatal and non-fatal cardiovascular disease in Latin America and the Caribbean: an individual-level pooled analysis of 31 cohort studies
Background: Estimates of the burden of cardio-metabolic risk factors in Latin America and the Caribbean (LAC) rely on relative risks (RRs) from non-LAC countries. Whether these RRs apply to LAC remains un- known.
Methods: We pooled LAC cohorts. We estimated RRs per unit of exposure to body mass index (BMI), systolic blood pressure (SBP), fasting plasma glucose (FPG), total cholesterol (TC) and non-HDL cholesterol on fatal (31 cohorts, n = 168,287) and non-fatal (13 cohorts, n = 27,554) cardiovascular diseases, adjusting for regression dilution bias. We used these RRs and national data on mean risk factor levels to estimate the number of cardiovascular deaths attributable to non-optimal levels of each risk factor.
Results: Our RRs for SBP, FPG and TC were like those observed in cohorts conducted in high-income countries; however, for BMI, our RRs were consistently smaller in people below 75 years of age. Across risk factors, we observed smaller RRs among older ages. Non-optimal SBP was responsible for the largest number of attributable cardiovascular deaths ranging from 38 per 10 0,0 0 0 women and 54 men in Peru, to 261 (Dominica, women) and 282 (Guyana, men). For non-HDL cholesterol, the lowest attributable rate was for women in Peru (21) and men in Guatemala (25), and the largest in men (158) and women (142) from Guyana.
Interpretation: RRs for BMI from studies conducted in high-income countries may overestimate disease burden metrics in LAC; conversely, RRs for SBP, FPG and TC from LAC cohorts are similar to those esti- mated from cohorts in high-income countries
El registro de Cáncer de Costa Rica: características, evolución y modernización
Population cancer registries are essential to monitor the incidence and measures of cancer control. The registry of tumors of Costa Rica was created in 1976, declaring the obligatory notification of any type of Cancer,and initiating the collection of data in 1977 becoming one of the first registries of Cancer of Latin America with international recognition. The national registry of tumors of Costa Rica has served so that other countries can learn and implement capture processes and data storage that guarantee the quality of the information. This article describes the process of tumor modernization, and the necessary guidelines to create a decentralized information system, nominal and integrated with all institutions of the health sector, providing timely and reliable information on the management of all cases of tumors that are detected in the country with the purpose of having accurate information for decision making in health surveillance and public policies.Los registros de cáncer poblacional son esenciales para monitorear la incidencia y las medidas de control del cáncer. El registro de tumores de Costa Rica fue creado en 1976, declarándose la notificación obligatoriade cualquier tipo de Cáncer, e iniciando la recolección de datos en 1977 convirtiéndose en uno de los primeros registros de Cáncer de América Latina con reconocimiento internacional. El registro nacional de tumoresde Costa Rica ha servido para que otros países puedan aprender e implementar procesos de captura y almacenamientos de datos que garanticen la calidad de la información. Este articulo describe el proceso de modernización de tumores, y las pautas necesarias para crear un sistema de información descentralizada, nominal e integrada con todas las instituciones del sector salud, proporcionando información oportuna y confiable en el manejo de todos los casos de tumores que se detectan en el país con el propósito de contar con información exacta para la toma de decisiones en vigilancia de la salud y políticas públicas
Health Risk Assessment in Children Occupationally and Para-Occupationally Exposed to Benzene Using a Reverse-Translation PBPK Model
Benzene is a known human carcinogen and one of the ten chemicals of major public health concern identified by the World Health Organization. Our objective was to evaluate benzene’s carcinogenic and non-carcinogenic health risks (current and projected) in highly exposed children in Yucatan, Mexico. Benzene exposure was estimated through a reverse-translation, four-compartment, physiologically based pharmacokinetic model (PBPK) based on previously performed urine trans, trans-muconic acid (benzene metabolite) determinations. Using a risk assessment methodology, the carcinogenic and non-carcinogenic risks of benzene were estimated for 6–12-year-old children from a family of shoemakers. The children’s hazard quotients for decreased lymphocyte count were 27 and 53 for 4 and 8 h/day exposure, respectively, and 37 for the projected 8 h/day exposure in adults. The risks of developing leukemia were 2–6 cases in 1000 children exposed 4 h/day; 4–10 cases in 1000 children exposed 8 h/day, and 2–9 cases in 1000 adults with an 8 h/day lifetime exposure. Children in Yucatan working in shoe-manufacturing workshops, or living next to them, are exposed to benzene concentrations above the reference concentration and have unacceptably high risks of presenting with non-carcinogenic and carcinogenic hematologic symptoms, now and in the future. Interventions to prevent further exposure and mitigate health risks are necessary
Should Patients with Chronic Disease Be Told to Gain Weight? The Obesity Paradox and Selection Bias
Relative to processed red meat, alternative protein sources are associated with a lower risk of hypertension and diabetes in a prospective cohort of French women
International audienceMany dietary guidelines recommend restricting the consumption of processed red meat (PRM) in favour of healthier foods such as fish, to reduce the risk of chronic conditions such as hypertension and diabetes. The objective of this study was to estimate the potential effect of replacing PRM for fatty fish, lean fish, red meat, eggs, pulses, or vegetables, on the risk of incident hypertension and diabetes. This was a prospective study of women in the E3N cohort study. Cases of diabetes and hypertension were based on self-report, specific questionnaires, and drug reimbursements. In the main analysis, information on regular dietary intake was assessed with a single food history questionaire, and food substitutions were modelled using cox proportional hazard models. 95 % confidence intervals were generated via bootstrapping. 71 081 women free of diabetes and 45 771 women free of hypertension were followed for an average of 18·7 and 18·3 years, respectively. 2681 incident cases of diabetes and 12 327 incident cases of hypertension were identified. Relative to PRM, fatty fish was associated with a 15 % lower risk of diabetes (HR = 0·85, 95 CI (0·73, 0·97)) and hypertension (HR = 0 85 (0·79, 0·91)). Between 3 and 10 % lower risk of hypertension or diabetes was also observed when comparing PRM with vegetables, unprocessed red meat or pulses. Relative to PRM, alternative protein sources such as fatty fish, unprocessed red meat, vegetables or pulses was associated with a lower risk of hypertension and diabetes
Western and Modern Mexican dietary patterns are directly associated with incident hypertension in Mexican women: a prospective follow-up study
Abstract Background Research has found that diet and dietary patterns are associated with blood pressure and hypertension. Limited research in this area has been conducted in a Mexican population. Methods We investigated the relation between dietary patterns (principal component analysis) and the incidence of self-reported treated hypertension in 62,913 women from the Mexican Teachers’ Cohort, a large population-based cohort of female Mexican teachers, who were free of hypertension at baseline in 2006–2008 when diet was assessed using a food frequency questionnaire. Dietary patterns were categorized into quartiles and logistic regression models were fit. Results Participants were 42.1 ± 7.3 years old, had a BMI 27.0 ± 4.4 and a cumulative incidence of hypertension of 4.6%. Between baseline and first follow-up (2011–2014) we identified 2916 incident cases of hypertension. We identified three major components. The first was loaded heavily with vegetables, fruits and legumes; the second component was loaded heavily with processed meats, fast foods, and red meat; and finally the third component was loaded heavily with corn tortillas, hot peppers, and sodas. We named the components as Fruits & Vegetables (FV), Western (W), and Modern Mexican (MM). The multivariable-adjusted odds of hypertension in the highest quartile of the W pattern were 24% higher than the odds for individuals in the lowest quartile (95%CI = 1.10, 1.40; P-trend = 0.0004); women in the highest quartile of the MM pattern had 15% higher odds than women in the lowest quartile (95%CI = 1.02, 1.29; P-trend = 0.01). The FV pattern was not significantly associated with hypertension (OR for extreme quartiles = 0.94; 95%CI = 0.84, 1.05; P-trend = 0.19). Conclusion The Western pattern and the Modern Mexican pattern, which showcases an undergoing nutrition transition, may affect the incidence of hypertension, whereas the FV pattern was not associated with hypertension. These findings are important in the prevention of hypertension and cardiovascular diseases in Mexico and possibly among Mexican people living in the US
Lifetime exposure to violence and other life stressors and hair cortisol concentration in women
Women are exposed to a variety of life stressors, particularly violence, during their lifetime which increases the risk of developing various psychiatric and somatic diseases, with the dysregulated secretion of cortisol as one potential biological mechanism. We examined the association between violence and other life stressors and hair cortisol concentration (HCC) in a population of urban women. We included 470 adult women (age = 21-86 years) attending the Cancer Detection Clinic in Iceland. The Life Stressor Checklist-Revised (LSC-R; 30-items) was used to assess exposure. HCC was measured with liquid chromatography coupled with tandem mass spectrometry. We used linear regression models to assess the association between life stressors and log-transformed HCC. The median HCC (pg/mg) in the study population was 4.9 (range 0.6-616.6). HCC was not associated with background covariates, including age (p = 0.868), education level (p = 0.824), marital status (p = 0.545), income (p = 0.363), occupation (p = 0.192), but associated with current smoking (p = 0.013). We noted a 3.3% (95% CI: 0.17-6.6%) associated increase in HCC per endorsed life stressor after adjusting for age and smoking, while non-violent life stressors were not associated with HCC. Per endorsed violence item, we observed a 10.2% (95% CI: 1.4-19.7%) associated increase in HCC after age and smoking adjustment. Women with lifetime exposure to both physical and sexual violence presented with higher HCC than unexposed women (p = 0.010), after age and smoking adjustment. Lifetime exposure to violence was associated with higher levels of HCC in a community sample of women. These findings need confirmation with prospective studies
Perceived stress and hair cortisol concentration in a study of Mexican and Icelandic women.
Hair cortisol concentration (HCC) represent a potential biomarker of chronic psychological stress. Previous studies exploring the association between perceived stress and HCC have been limited to relatively small and selected populations. We collected hair samples from 881 women from the Mexican Teachers' Cohort (MTC) and 398 women from the Icelandic SAGA pilot-cohort following identical protocols. HCC was quantified using liquid chromatography coupled with tandem mass spectrometry. The self-reported Perceived Stress Scale (PSS, 10 and 4 item, range 0-40 and 0-16) was used to assess psychological stress. We conducted multivariable linear regression analyses to assess the association between perceived stress and log-transformed HCC in the combined sample and in each cohort separately. MTC participants had slightly higher HCC and PSS scores than SAGA participants (median HCC 6.0pg/mg vs. 4.7pg/mg and mean PSS-10 score 12.4 vs. 11.7, respectively). After adjusting for sociodemographic factors and health behaviors, we observed a 1.4% (95% CI 0.6, 2.1) increase in HCC for each unit increase in the PSS-10 score in the combined sample. Furthermore, PSS-10 quintiles were associated with a 24.3% (95% CI 8.4, 42.6, mean logHCC 1.8 vs 1.6) increase in HCC when comparing the highest to the lowest quintile, after multivariable adjustment. Similar results were obtained when we analyzed each cohort separately and when using the PSS-4. Despite relatively small absolute differences, an association between perceived stress and HCC was found in a sample of women from two diverse geographical and cultural backgrounds supporting the hypothesis that HCC is a viable biomarker in studies of chronic psychological stress