The impact of lifecourse socio-economic position and individual social mobility on breast cancer risk

Biological embodiment of educational attainment and future risk of breast cancer: findings from a French prospective cohort

BACKGROUND

Women with higher educational attainment have a higher risk of developing breast cancer (BC). Despite the acknowledged impact of reproductive and lifestyle factors, some excess risks remain unexplained. Many studies support the hypothesis that education has a distinctive effect on physiological processes associated with health, independently of known risk factors.

OBJECTIVES

In this study, we aimed to determine whether the biological embodiment of education could be part of the observed social inequalities in BC risk. We focused on biomarkers from several physiological systems examined individually, and jointly through a biological health score (BHS).

DESIGN

Prospective cohort study.

SETTING

This study, based on a subsample of the French E3N cohort, included women with biological data from four nested case-control studies.

PARTICIPANTS

The study included 3048 postmenopausal women (17% BC).

MAIN OUTCOME MEASURES

We first evaluated the association between educational attainment and each biomarker, separately (N=11) and by combining them into a BHS, indicative of an augmented biological health hazard when elevated. Finally, we explored the relationships between the socially patterned biomarkers and BHS, and risk of incident BC.

RESULTS

Women with higher educational attainment exhibited a lower BHS in comparison to those with lower educational attainment (βhigh education=-0.21 (95% CI -0.42; 0.01), model 2). Specific biomarkers associated with the cardiovascular (systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides (TG), high-density lipoprotein (HDL)), inflammatory (C reactive protein (CRP)) and hormonal systems (sex hormone-binding globulin (SHBG) and oestradiol) were found socially distributed (OR CRP-high=0.70 (95% CI 0.54; 0.91), OR TG-high=0.79 (95% CI 0.61; 1.04), OR DBP-high=0.69 (95% CI 0.53; 0.90), OR SBP-high=0.57 (95% CI 0.44; 0.74), OR HDL-high=0.79 (95% CI 0.60; 1.03), (OR SHBG-high=0.67 (95% CI 0.52; 0.88), OR oestradiol-high=1.34 (95% CI 1.00; 1.79); model 1). Associations persisted after adjustment for cofounders and a large set of potential mediators for two of the investigated cardiovascular markers (OR DBP-high=0.75 (95% CI 0.57; 1.00), OR SBP-high=0.61 (95% CI 0.46; 0.81); model 2). No associations were found between the socially stratified biomarkers and BHS with risk of BC.

CONCLUSION

Educational attainment has a direct impact on biological processes suggesting that the biological embodiment of the social environment could be a potential pathway that mediates the association between educational attainment and health. Further studies are needed to specifically investigate the relationships between socially stratified biomarkers and BC risk.

Educational level and characteristics of invasive breast cancer: findings from a French prospective cohort

PURPOSE

Breast cancer (BC) characteristics are known to influence patients survival. Social differences have been reported by previous studies for those characteristics but questions persist because of inconsistent conclusions. We aimed to investigate the impact of education on BC stage, grade, and hormone receptor (HR) status, while adjusting for potential confounders including a broad set of health behaviors, anthropometric measures, and reproductive factors.

METHODS

In the French E3N cohort, 5236 women developed a primary invasive BC for which there was available information on stage, grade, and HR status. No multivariate analyses was performed for BC stage based on the lack of association in bivariate analyses. Odds ratios and confidence intervals were estimated using multinomial logistic regression models for BC grade or binomial logistic regression models for HR status of BC.

RESULTS

Women with a lower education were diagnosed with higher grade BC compared to women with a higher education (1.32 [1.12; 1.57]). This association was slightly attenuated after adjustment for covariates independently and more strongly affected in the fully adjusted model (1.20 [0.99; 1.45]). A significant association was observed between lower education and HR- status of BC (1.20 [1.02; 1.42]) attenuated after adjustment for age at first childbirth (1.12 [0.95; 1.33]).

CONCLUSION

In this cohort, education was associated with BC grade and HR status but not stage at diagnosis. The link between education and BC grade was not entirely explained by the different adjustments. A specific mechanism could be at play and deserves further investigations.

Interaction of sedentary behaviour and educational level in breast cancer risk

OBJECTIVE

This cross-sectional study aims to analyse the relationship between sedentary behaviour and breast cancer (BC) risk from a social perspective.

METHODS

Women aged 45-70 who participated in the Valencia Region Breast Cancer Screening Programme (2018-2019) were included, with a total of 121,359 women analysed, including 506 with cancer and 120,853 without cancer. The response variable was BC (screen-detected) and the main explanatory variable was sedentary behaviour (≤2 / >2-≤3 / >3-≤5 / >5 hours/day, h/d). Nested logistic regression models (M) were estimated: M1: sedentary behaviour adjusted for age and family history of BC; M2: M1 + hormonal/reproductive variables (menopausal status, number of pregnancies, hormone replacement therapy; in addition, months of breastfeeding was added for a subsample of women with one or more live births); M3: M2 + lifestyle variables (body mass index, smoking habits); M4: M3 + socioeconomic variables (educational level, occupation); Final model: M4 + gender variables (childcare responsibilities, family size). Interaction between sedentary behaviour and educational level was analysed in the Final model. Moreover, for the whole sample, postmenopausal women and HR+ BC, the Final model was stratified by educational level.

RESULTS

Sedentary behaviour was associated with an increased risk of BC with a nearly statistically significant effect in the Final model (>2-≤3 h/d: OR = 1.22 (0.93-1.61); >3-≤5 h/d: OR = 1.14 (0.86-1.52); >5: OR = 1.19 (0.89-1.60)). For women with a low educational level, sitting more than 2 h/d was associated with an increased risk of BC in the whole sample (>2-≤3 h/d OR = 1.93 (1.19-3.21); in postmenopausal women (>2-≤3 h/d, OR = 2.12 (1.18-2.96), >5h/d OR = 1.75 (1.01-3.11)) and in HR+ BC (>2-≤3h/d, OR = 2.15 (1.22-3.99)). Similar results were observed for women with one or more live births. Conclusions Sitting >2 h/d is associated with BC risk in women with low educational level, especially in postmenopausal women and those with live births.

Risk factors for breast cancer among women in Freetown, Sierra Leone, 2017: a case-control study

Introduction

breast cancer is the most commonly diagnosed malignancy and an important cause of cancer death among females worldwide. The disease accounted for 25% (1.67 million) of new cancer cases and the fifth cause of cancer deaths. Incidence of all types of cancers is approximately 25% in Sierra Leone. However, there was no documented evidence on risk factors for breast cancer among women in the country. The main aim of this study was to assess risk factors associated with breast cancer among women screened for breast cancer in Freetown Sierra Leone.

Methods

we conducted a case-control study on breast cancer involving 116 confirmed breast cancer cases and 116 controls. Questionnaire was designed to collect data on socio-demographic, reproductive and behavioral risk factors. Analysis was carried using logistic regression to assess the associations between breast cancer and the risk factors.

Results

in the final multiple logistic regression, had formal educational level, (aOR 0.1, 0.03-0.26, p= 0.001) physical activity for more than 30 minutes per week (aOR 0.5 (0.9- 0.7, p=0.001). Cigarette smoking (aOR 4.8, 1.2-18.5, p=0.023) and family history of breast cancer (aOR 9.9 cigarette smoking (OR 4.4, 1.2-18.5, p=0.023) and family history of breast cancer (OR 9.9, 2.7-36.45, p=0.040) were identified as the main risk factors for breast cancer. This study did not find any statistically significant associations between reproductive risk factors and breast cancer.

Conclusion

risk factors for breast cancer among women in Sierra Leone include educational level, physical activity, cigarette smoking and family history of breast cancer. We recommended screening program for women above 40 years and had history of breast cancer. Also, to establish breast cancer registry.

Mediating Role of Lifestyle Behaviors in the Association between Education and Cancer: Results from the European Prospective Investigation into Cancer and Nutrition

BACKGROUND

Many studies have shown that socioeconomic position (SEP) is associated with the incidence of malignant tumors at different sites. This study aims to estimate the association between educational level (as proxy for SEP) and cancer incidence and to understand whether the observed associations might be partially explained by lifestyle behaviors.

METHODS

The analyses were performed on data from the European Prospective Investigation into Cancer and Nutrition (EPIC) study, globally and by sex. We used Cox proportional hazards models together with mediation analysis to disentangle the total effect (TE) of educational level [measured through the Relative Index of Inequality (RII)] on cancer incidence into pure direct (PDE) and total indirect (TIE) effect, unexplained and explained by mediators, respectively. PDE and TIE were then combined to compute the proportions mediated (PM).

RESULTS

After an average of 14 years of follow-up, 52,422 malignant tumors were ascertained. Low educated participants showed higher risk of developing stomach, lung, kidney (in women), and bladder (in men) cancers, and, conversely, lower risk of melanoma and breast cancer (in post-menopausal women), when compared with more educated participants. Mediation analyses showed that portions of the TE of RII on cancer could be explained by site-specific related lifestyle behaviors for stomach, lung, and breast (in women).

CONCLUSIONS

Cancer incidence in Europe is determined at least in part by a socioeconomically stratified distribution of risk factors.

IMPACT

These observational findings support policies to reduce cancer occurrence by altering mediators, such as lifestyle behaviors, particularly focusing on underprivileged strata of the population.

Breast Cancer Characteristics in the Population of Survivors Participating in the World Trade Center Environmental Health Center Program 2002-2019

The destruction of World Trade Center on 11 September 2001 exposed local community members to a complex mixture of known carcinogens and potentially carcinogenic substances. To date, breast cancer has not been characterized in detail in the WTC-exposed civilian populations. The cancer characteristics of breast cancer patients were derived from the newly developed Pan-Cancer Database at the WTC Environmental Health Center (WTC EHC). We used the Surveillance, Epidemiology, and End Results (SEER) Program breast cancer data as a reference source. Between May 2002 and 31 December 2019, 2840 persons were diagnosed with any type of cancer at the WTC EHC, including 601 patients with a primary breast cancer diagnosis (592 women and 9 men). There was a higher proportion of grade 3 (poorly differentiated) tumors (34%) among the WTC EHC female breast cancers compared to that of the SEER-18 data (25%). Compared to that of the SEER data, female breast cancers in the WTC EHC had a lower proportion of luminal A (88% and 65%, respectively), higher proportion of luminal B (13% and 15%, respectively), and HER-2-enriched (5.5% and 7%, respectively) subtypes. These findings suggest considerable differences in the breast cancer characteristics and distribution of breast cancer intrinsic subtypes in the WTC-exposed civilian population compared to that of the general population. This is important because of the known effect of molecular subtypes on breast cancer prognosis.