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Background: Black women have a disproportionately higher burden of both preeclamptic pregnancy and stroke compared with White women, but virtually all existing evidence on this possible association has been generated from women of European ancestry. Methods: In the Black Women's Health Study, a prospective cohort of U.S. Black women who enrolled in 1995, 42,924 participants were parous and free of cardiovascular disease at baseline. Biennial questionnaires included questions on preeclampsia, gestational hypertension, and stroke. We sought the medical records for participants who reported a stroke, and we reviewed them blinded to reproductive history. Cox proportional-hazards models, with control for potential confounders, were used to estimate hazard ratios and 95% confidence intervals (CIs). Results: Over a median of 22 years of follow-up, there were 1555 incident strokes, including 310 among 4938 women with a history of hypertensive disorders of pregnancy (HDOP). The multivariable hazard ratio for stroke for women with any HDOP compared with those who had never experienced HDOP was 1.66 (95% CI, 1.46 to 1.89). Comparable hazard ratios were 1.53 (95% CI, 1.29 to 1.82) for preeclampsia and 1.81 (95% CI, 1.53 to 2.13) for gestational hypertension only. Associations were similar among women under age 55 years and those aged 55 years and older. Conclusions: In this prospective study of Black women, a history of HDOP was associated with an estimated 66% increased long-term risk of stroke. This association may contribute to the disproportionately higher stroke incidence in Black women given the higher prevalence of HDOP in this population. (Funded by the U.S. National Institutes of Health.) [ABSTRACT FROM AUTHOR]

In 2022, more than 100 000 non‐Hodgkin lymphoma (NHL) diagnoses are expected, yet few risk factors are confirmed. In this study, data from six US‐based cohorts (568 717 individuals) were used to examine body size and risk of NHL. Over more than 20 years of follow‐up, 11 263 NHLs were identified. Hazard ratios (HRs) and 95% confidence intervals (CI) estimated associations with NHLs for adult body mass index (BMI), height, weight change, waist circumference and predicted fat mass. Adult height was broadly associated with NHL, but most strongly with B‐cell NHLs among non‐White participants (e.g. HRBLACK = 2.06, 95% CI: 1.62–2.62). However, the strongest association among the anthropometric traits examined was for young adult BMI and risk of diffuse large B‐cell lymphoma (DLBCL), particularly those who maintained a higher BMI into later adulthood. Individuals with BMI over 30 kg/m2 throughout adulthood had more than double the DLBCL risk (HR = 2.67, 95% CI: 1.71–4.17) compared to BMI 18.5–22.9 kg/m2. Other anthropometric traits were not associated with NHL after controlling for BMI. These results suggest that sustained high BMI is a major driver of DLBCL risk. If confirmed, we estimate that up to 23.5% of all DLBCLs (and 11.1% of all NHLs) may be prevented with avoidance of young adult obesity. [ABSTRACT FROM AUTHOR]

Background: Research on psychosocial stress and risk of breast cancer has produced conflicting results. Few studies have assessed this relation by breast cancer subtype or specifically among Black women, who experience unique chronic stressors.Methods: We used prospective data from the Black Women's Health Study, an ongoing cohort study of 59,000 US Black women, to assess neighborhood- and individual-level psychosocial factors in relation to risk of breast cancer. We used factor analysis to derive two neighborhood score variables after linking participant addresses to US Census data (2000 and 2010) on education, employment, income and poverty, female-headed households, and Black race for all households in each residential block group. We used Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for established breast cancer risk factors.Results: During follow-up from 1995 to 2017, there were 2167 incident invasive breast cancer cases (1259 estrogen receptor positive (ER +); 687 ER negative (ER-)). For ER- breast cancer, HRs were 1.26 (95% CI 1.00-1.58) for women living in the highest quartile of neighborhood disadvantage relative to women in the lowest quartile, and 1.24 (95% CI 0.98-1.57) for lowest versus highest quartile of neighborhood socioeconomic status (SES). For ER+ breast cancer, living in the lowest quartile of neighborhood SES was associated with a reduced risk of ER+ breast cancer (HR = 0.83, 95% CI 0.70-0.98). With respect to individual-level factors, childhood sexual abuse (sexual assault ≥ 4 times vs. no abuse: HR = 1.35, 95% CI 1.01-1.79) and marital status (married/living together vs. single: HR = 1.29, 95% CI 1.08-1.53) were associated with higher risk of ER+, but not ER- breast cancer.Conclusion: Neighborhood disadvantage and lower neighborhood SES were associated with an approximately 25% increased risk of ER- breast cancer in this large cohort of Black women, even after control for multiple behaviors and lifestyle factors. Further research is need to understand the underlying reasons for these associations. Possible contributing factors are biologic responses to the chronic stress/distress experienced by individuals who reside in neighborhoods characterized by high levels of noise, crime and unemployment or the direct effects of environmental toxins. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC), the most commonly occurring type of primary liver cancer, has been increasing in incidence worldwide. Vitamin D, acquired from sunlight exposure, diet, and dietary supplements, has been hypothesized to impact hepatocarcinogenesis. However, previous epidemiologic studies examining the associations between dietary and serum vitamin D reported mixed results. The purpose of this study was to examine the association between ambient ultraviolet (UV) radiation exposure and HCC risk in the U.S.Methods: The Surveillance, Epidemiology, and End Results (SEER) database provided information on HCC cases diagnosed between 2000 and 2014 from 16 population-based cancer registries across the U.S. Ambient UV exposure was estimated by linking the SEER county with a spatiotemporal UV exposure model using a geographic information system. Poisson regression with robust variance estimation was used to calculate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the association between ambient UV exposure per interquartile range (IQR) increase (32.4 mW/m2) and HCC risk adjusting for age at diagnosis, sex, race, year of diagnosis, SEER registry, and county-level information on prevalence of health conditions, lifestyle, socioeconomic, and environmental factors.Results: Higher levels of ambient UV exposure were associated with statistically significant lower HCC risk (n = 56,245 cases; adjusted IRR per IQR increase: 0.83, 95% CI 0.77, 0.90; p < 0.01). A statistically significant inverse association between ambient UV and HCC risk was observed among males (p for interaction = 0.01) and whites (p for interaction = 0.01).Conclusions: Higher ambient UV exposure was associated with a decreased risk of HCC in the U.S. UV exposure may be a potential modifiable risk factor for HCC that should be explored in future research. [ABSTRACT FROM AUTHOR]

Background: Radon and its decay products, a source of ionizing radiation, are primarily inhaled and can deliver a radiation dose to breast tissue, where they may continue to decay and emit DNA damage-inducing particles. Few studies have examined the relationship between radon and breast cancer.Methods: The Nurses' Health Study II (NHSII) includes U.S. female registered nurses who completed biennial questionnaires since 1989. Self-reported breast cancer was confirmed from medical records. County-level radon exposures were linked with geocoded residential addresses updated throughout follow-up. Time-varying Cox regression models adjusted for established breast cancer risk factors were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).Results: From 1989 to 2013, 3966 invasive breast cancer cases occurred among 112,639 participants. Increasing radon exposure was not associated with breast cancer risk overall (adjusted HR comparing highest to lowest quintile = 1.06, 95% CI: 0.94, 1.21, p for trend = 0.30). However, women in the highest quintile of exposure (≥74.9 Bq/m3) had a suggested elevated risk of ER-/PR- breast cancer compared to women in the lowest quintile (<27.0 Bq/m3) (adjusted HR = 1.38, 95% CI: 0.97, 1.96, p for trend = 0.05). No association was observed for ER+/PR+ breast cancer.Conclusions: Although we did not find an association between radon exposure and risk of overall or ER+/PR+ breast cancer, we observed a suggestive association with risk of ER-/PR- breast cancer. [ABSTRACT FROM AUTHOR]

Background: Limited knowledge regarding the reproducibility of biomarkers in 24-h urine samples has hindered the collection and use of the samples in epidemiologic studies. Objective: We aimed to evaluate the reproducibility of various markers in repeat 24-h urine samples. Design: We calculated intraclass correlation coefficients (ICCs) of biomarkers measured in 24-h urine samples that were collected in 3168 participants in the NHS (Nurses' Health Study), NHSII (Nurses' Health Study II), and Health Professionals Follow-Up Study. Results: In 742 women with 4 samples each collected over the course of 1 y, ICCs for sodium were 0.32 in the NHS and 0.34 in the NHSII. In 2439 men and women with 2 samples each collected over 1 wk to =1 mo, the ICCs ranged from 0.33 to 0.68 for sodium at various intervals between collections. The urinary excretion of potassium, calcium, magnesium, phosphate, sulfate, and other urinary markers showed generally higher reproducibility (ICCs >0.4). In 47 women with two 24-h urine samples, ICCs ranged from 0.15 (catechin) to 0.75 (enterolactone) for polyphenol metabolites. For phthalates, ICCs were generally =0.26 except for monobenzyl phthalate (ICC: 0.55), whereas the ICC was 0.39 for bisphenol A (BPA). We further estimated that, for the large majority of the biomarkers, the mean of three 24-h urine samples could provide a correlation of =0.8 with true long-term urinary excretion. Conclusions: These data suggest that the urinary excretion of various biomarkers, such as minerals, electrolytes, most polyphenols, and BPA, is reasonably reproducible in 24-h urine samples that are collected within a few days or =1 y. Our findings show that three 24-h samples are sufficient for the measurement of long-term exposure status in epidemiologic studies. [ABSTRACT FROM AUTHOR]

Background: Vitamin D deficiency, which has been linked to an increased risk of colorectal cancer, is particularly common among African Americans. Previous studies of vitamin D status and breast cancer risk, mostly conducted in white women, have had conflicting results. We examined the relationship between predicted vitamin D status and incidence of breast cancer in a cohort of 59,000 African American women.Methods: Participants in the Black Women's Health Study have been followed by biennial mail questionnaires since 1995, with self-reported diagnoses of cancer confirmed by hospital and cancer registry records. Repeated five-fold cross-validation with linear regression was used to derive the best 25-hydroxyvitamin D (25(OH)D) prediction model based on measured 25(OH)D in plasma specimens obtained from 2856 participants in 2013-2015 and questionnaire-based variables from the same time frame. In the full cohort, including 1454 cases of incident invasive breast cancer, Cox proportional hazards models were used to compute the incidence rate ratio (IRR) for each quartile of predicted vitamin D score relative to the highest quartile. Predicted vitamin D score for each two-year exposure period was a cumulative average of predicted scores from all exposure periods up to that time.Results: Twenty-two percent of women with measured 25(OH)D were categorized as "deficient" (<20 ng/mL) and another 25 % as "insufficient" (20-29 ng/mL). The prediction model explained 25 % of variation in measured 25(OH)D and the correlation coefficient for predicted versus observed 25(OH)D averaged across all cross-validation runs was 0.49 (SD 0.026). Breast cancer risk increased with decreasing quartile of predicted 25(OH)D, p for trend 0.015; the IRR for the lowest versus highest quartile was 1.23 (95 % confidence interval 1.04, 1.46).Conclusions: In prospective data, African American women in the lowest quartile of cumulative predicted 25(OH)D were estimated to have a 23 % increased risk of breast cancer relative to those with relatively high levels. Preventing vitamin D deficiency may be an effective means of reducing breast cancer incidence in African American women. [ABSTRACT FROM AUTHOR]

Background: To date, there is limited and inconsistent epidemiologic evidence for associations of adolescent diet with mammographic breast density, a strong and consistent predictor of breast cancer. We investigated the association of adolescent fiber intake with mammographic density in premenopausal women.Methods: This study included 743 cancer-free premenopausal women (mean age, 44.9 years) within the Nurses' Health Study II cohort. Percent breast density, absolute dense and non-dense areas were measured from digitized film mammograms using a computer-assisted thresholding technique. Adolescent and adult diet were assessed with a food frequency questionnaire; energy-adjusted nutrient intakes were estimated for each food item. Information regarding breast cancer risk factors was obtained from baseline or biennial questionnaires closest to the mammogram date. We used generalized linear regression to quantify associations between quartiles of adolescent fiber intake and each of the breast density measures, adjusted for potential confounders. Associations were examined separately for total fiber intake; fiber from fruits, vegetables, legumes, and cereal; and food sources of fiber (fruits, vegetables, and nuts).Results: In multivariable analyses, total fiber intake during adolescence was not associated with percent breast density (p for trend = 0.64), absolute dense area (p for trend = 0.80), or non-dense area (p for trend = 0.75). Similarly, neither consumption of fiber from fruits, vegetables, legumes, or cereal nor specific sources of fiber intake (fruits, vegetables, or nuts) during adolescence were associated with any of the mammographic density phenotypes.Conclusions: Our findings do not support the hypothesis that adolescent fiber intake is associated with premenopausal mammographic breast density. [ABSTRACT FROM AUTHOR]

Ambient dioxin exposure from industrial sources, excluding exposures from occupations and accidental releases/contamination, may be associated with risk of developing hepatocellular carcinoma (HCC). The objective of this study was to examine the association between county-level ambient dioxin air emissions from industrial sources and HCC risk in the US. We obtained information on 90,359 incident HCC cases diagnosed between 2000 and 2016 from population-based cancer registries across the US in the Surveillance, Epidemiology, and End Results (SEER) database. Dioxin emissions from 1987 to 2007 from a nationwide spatial database of historical dioxin-emitting facilities were linked to the SEER county of residence at diagnosis using a geographic information system (GIS). Poisson regression with robust variance estimation was used to calculate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the association between county-level dioxin emissions and HCC rates adjusting for individual-level age at diagnosis, sex, race/ethnicity, year of diagnosis, SEER registry, and county-level information on health conditions, lifestyle factors, and socioeconomic status. There was no association between dioxin emissions based on the number of dioxin-emitting facilities within a county or average annual emissions within a county and HCC risk. In analyses by facility type, there were positive associations between county-level dioxin emissions from coal-fired power plants (adjusted IRR 1.09, 95% CI 1.01–1.17), but not with the number of these facilities. Similarly, positive associations for industrial boilers and sewage sludge incinerators were evident, but not consistent across both exposure metrics. Future research should incorporate individual-level data to further explore the findings suggested by these ecologic analyses. • An ecological study examined dioxin exposure and hepatocellular carcinoma risk. • Exposure was estimated from a historical database of dioxin-emitting facilities. • Cases were ascertained from population-based cancer registries. • There was no association with dioxin emissions from all industrial sources. • These findings should be interpreted as hypothesis-generating. [ABSTRACT FROM AUTHOR]

Epidemiological and other evidence suggests that vitamin D may be protective against several chronic diseases. Assessing vitamin D status in epidemiological studies, however, is challenging given finite resources and limitations of commonly used approaches. Using multivariable linear regression, we derived predicted 25-hydroxyvitamin D (25(OH)D) scores based on known determinants of circulating 25(OH)D, including age, race, UV-B radiation flux at residence, dietary and supplementary vitamin D intakes, BMI, physical activity, alcohol intake, post-menopausal hormone use (women only) and season of blood draw, in three nationwide cohorts: the Nurses' Health Study, Nurses' Health Study II and the Health Professionals Follow-up Study. The model r2 for each cohort ranged from 0·25 to 0·33. We validated the prediction models in independent samples of participants from these studies. Mean measured 25(OH)D levels rose with increasing decile of predicted 25(OH)D score, such that the differences in mean measured 25(OH)D between the extreme deciles of predicted 25(OH)D were in the range 8·7–12·3 ng/ml. Substituting predicted 25(OH)D scores for measured 25(OH)D in a previously published case–control analysis of colorectal cancer yielded similar effect estimates with OR of approximately 0·8 for a 10 ng/ml difference in either plasma or predicted 25(OH)D. We conclude that these data provide reasonable evidence that a predicted 25(OH)D score is an acceptable marker for ranking individuals by long-term vitamin D status and may be particularly useful in research settings where biomarkers are not available for the majority of a study population. [ABSTRACT FROM PUBLISHER]

Background: Environmental exposure to polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyldichloroethylene (p, p'-DDE) has been associated with the risk of non-Hodgkin lymphoma.Methods: We conducted a case-control study nested within the Physicians' Health Study, a prospective cohort established in 1982. We measured concentrations of PCBs and p,p'-DDE in baseline blood samples from 205 men later diagnosed with non-Hodgkin lymphoma and 409 age- and race-matched controls. Lipid-adjusted organochlorine concentrations were categorized into quintiles based on the distribution among controls. We used conditional logistic regression to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for each quintile relative to the lowest quintile. We also evaluated these associations for major histologic subtypes of non-Hodgkin lymphoma.Results: The risk of non-Hodgkin lymphoma was positively associated with the sum of 51 PCB congeners assayed (SigmaPCB); the group of immunotoxic congeners; the individual congeners 118, 138, 153, and 180; and the sum of these 4 congeners. The simple OR for the highest quintile of lipid-adjusted SigmaPCB versus the lowest was 1.9 (95% CI = 1.1-3.2; test for trend, P = 0.001), with similar trends for individual congeners and groups defined as above. Adjustment for height, body mass index, alcohol intake, smoking, and fish intake did not substantially change the effect estimates. No association was observed for p,p'-DDE. There was no evidence of statistical heterogeneity in effects by histologic subtype of lymphoma; however, this analysis was underpowered.Conclusions: These results support the hypothesis of a positive association between PCB exposure and development of NHL in men. [ABSTRACT FROM AUTHOR]

Background: Obesity and elevated breast density are common risk factors for breast cancer, and their effects may vary by estrogen receptor (ER) subtype. However, their joint effects on ER subtype-specific risk are unknown. Understanding this relationship could enhance risk stratification for screening and prevention. Thus, we assessed the association between breast density and ER subtype according to body mass index (BMI) and menopausal status.Methods: We conducted a case-control study nested within two mammography screening cohorts, the Mayo Mammography Health Study and the San Francisco Bay Area Breast Cancer SPORE/San Francisco Mammography Registry. Our pooled analysis contained 1538 ER-positive and 285 ER-negative invasive breast cancer cases and 4720 controls matched on age, menopausal status at time of mammogram, and year of mammogram. Percent density was measured on digitized film mammograms using computer-assisted techniques. We used polytomous logistic regression to evaluate the association between percent density and ER subtype by BMI subgroup (normal/underweight, < 25 kg/m2 versus overweight/obese, ≥ 25 kg/m2). We used Wald chi-squared tests to assess for interactions between percent density and BMI. Our analysis was stratified by menopausal status and hormone therapy usage at the time of index mammogram.Results: Percent density was associated with increased risk of overall breast cancer regardless of menopausal status or BMI. However, when analyzing breast cancer across ER subtype, we found a statistically significant (p = 0.008) interaction between percent density and BMI in premenopausal women only. Specifically, elevated percent density was associated with a higher risk of ER-negative than ER-positive cancer in overweight/obese premenopausal women [OR per standard deviation increment 2.17 (95% CI 1.50-3.16) vs 1.33 (95% CI 1.11-1.61) respectively, Pheterogeneity = 0.01]. In postmenopausal women, elevated percent density was associated with similar risk of ER-positive and ER-negative cancers, and no substantive differences were seen after accounting for BMI or hormone therapy usage.Conclusions: The combination of overweight/obesity and elevated breast density in premenopausal women is associated with a higher risk of ER-negative compared with ER-positive cancer. Eighteen percent of premenopausal women in the USA have elevated BMI and breast density and may benefit from lifestyle modifications involving weight loss and exercise. [ABSTRACT FROM AUTHOR]

Background: Findings from a recent prospective cohort study in California suggested increased risk of breast cancer associated with higher exposure to certain carcinogenic and estrogen-disrupting hazardous air pollutants (HAPs). However, to date, no nationwide studies have evaluated these possible associations. Our objective was to examine the impacts of mammary carcinogen and estrogen disrupting HAPs on risk of invasive breast cancer in a nationwide cohort.Methods: We assigned HAPs from the US Environmental Protection Agency's 2002 National Air Toxics Assessment to 109,239 members of the nationwide, prospective Nurses' Health Study II (NHSII). Risk of overall invasive, estrogen receptor (ER)-positive (ER+), and ER-negative (ER-) breast cancer with increasing quartiles of exposure were assessed in time-varying multivariable proportional hazards models, adjusted for traditional breast cancer risk factors.Results: A total of 3321 invasive cases occurred (2160 ER+, 558 ER-) during follow-up 1989-2011. Overall, there was no consistent pattern of elevated risk of the HAPs with risk of breast cancer. Suggestive elevations were only seen with increasing 1,2-dibromo-3-chloropropane exposures (multivariable adjusted HR of overall breast cancer = 1.12, 95% CI: 0.98-1.29; ER+ breast cancer HR = 1.09; 95% CI: 0.92, 1.30; ER- breast cancer HR = 1.14; 95% CI: 0.81, 1.61; each in the top exposure quartile compared to the lowest).Conclusions: Exposures to HAPs during adulthood were not consistently associated with an increased risk of overall or estrogen-receptor subtypes of invasive breast cancer in this nationwide cohort of women. [ABSTRACT FROM AUTHOR]

Evidence suggests that aspirin use reduces the occurrence of colorectal neoplasia. Few studies have investigated the association among Black Americans, who are disproportionately burdened by the disease. We assessed aspirin use in relation to colorectal adenoma among Black women. The Black Women's Health Study is a prospective cohort of self-identified Black American women established in 1995. Participants reported regular aspirin use on baseline and follow-up questionnaires. Beginning in 1999, participants reported undergoing a colonoscopy or sigmoidoscopy, the only procedures through which colorectal adenomas can be diagnosed. Multivariable logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between aspirin use and colorectal adenoma among 34 397 women who reported at least 1 colonoscopy or sigmoidoscopy. From 1997 through 2018, 1913 women were diagnosed with an adenoma. Compared to nonaspirin users, regular users had 14% (OR = 0.86, 95% CI: 0.78-0.95) lower odds of adenoma. The odds of adenoma decreased with increasing duration of aspirin use (≥10 years: OR = 0.80, 95% CI: 0.66-0.96). Initiating aspirin at a younger age was associated with a reduced adenoma occurrence (age < 40 years at initiation: OR = 0.69, 95% CI: 0.55-0.86). Regular aspirin use was associated with a decreased odds of colorectal adenoma in our study of Black women. These findings support evidence demonstrating a chemopreventive impact of aspirin on colorectal neoplasia and suggest that aspirin may be a useful prevention strategy among US Black women., (© 2023 UICC.)

Background: Socioeconomic and health-related factors, including comorbid illness, may affect mammography screening rates and subsequently contribute to breast cancer outcomes. We explored the association between diabetes and mammography screening, and whether this association varied between racial, ethnic, and geographic groups. Methods: Cross-sectional data from the 2012, 2014, 2016, and 2018 Behavioral Risk Factor Surveillance System were used to fit logistic regression models assessing the association between diabetes and up-to-date mammography screening in 497,600 women, aged 50-74 years. Participants were considered exposed if they responded "yes" to "(Ever told) you have diabetes?" and up to date on screening if they responded "yes" to having a mammogram within the past 2 years. Models were adjusted for age, health status, socioeconomic, and access variables. Results: The majority of participants were White (79.6%), non-Hispanic (88.9%), and up to date on screening (78.8%). Overall, 16.8% reported having diabetes. In fully adjusted models, White women with diabetes were 12% more likely to be up to date on screening (odds ratio [OR]: 1.12, 95% confidence interval [CI]: 1.06-1.19) than those without diabetes. Black/African American women and those of Hispanic ethnicity with diabetes were more likely to report being up to date with mammography (OR Black : 1.28, 95% CI: 1.12-1.45; OR Hispanic : 1.19, 95% CI: 1.13-1.24) than those without. Patterns were similar across geographic regions. Conclusions: Women of ages 50-74 years with diabetes were more likely to be up to date on screening than women without diabetes. Chronic disease management may represent an opportunity to address cancer screening.

Purpose: Breast cancer risk prediction models are used to identify high-risk women for early detection, targeted interventions, and enrollment into prevention trials. We sought to develop and evaluate a risk prediction model for breast cancer in US Black women, suitable for use in primary care settings., Methods: Breast cancer relative risks and attributable risks were estimated using data from Black women in three US population-based case-control studies (3,468 breast cancer cases; 3,578 controls age 30-69 years) and combined with SEER age- and race-specific incidence rates, with incorporation of competing mortality, to develop an absolute risk model. The model was validated in prospective data among 51,798 participants of the Black Women's Health Study, including 1,515 who developed invasive breast cancer. A second risk prediction model was developed on the basis of estrogen receptor (ER)-specific relative risks and attributable risks. Model performance was assessed by calibration (expected/observed cases) and discriminatory accuracy (C-statistic)., Results: The expected/observed ratio was 1.01 (95% CI, 0.95 to 1.07). Age-adjusted C-statistics were 0.58 (95% CI, 0.56 to 0.59) overall and 0.63 (95% CI, 0.58 to 0.68) among women younger than 40 years. These measures were almost identical in the model based on estrogen receptor-specific relative risks and attributable risks., Conclusion: Discriminatory accuracy of the new model was similar to that of the most frequently used questionnaire-based breast cancer risk prediction models in White women, suggesting that effective risk stratification for Black women is now possible. This model may be especially valuable for risk stratification of young Black women, who are below the ages at which breast cancer screening is typically begun., Competing Interests: Tracy BattagliaResearch Funding: American Cancer Society, Patient Centered Outcomes Research Institute, NIH NCATs (Inst) Elisa V. BanderaConsulting or Advisory Role: PfizerNo other potential conflicts of interest were reported.

Hair relaxers and leave-in conditioners and oils, commonly used by Black/African American women, may contain estrogens or estrogen-disrupting compounds. Thus, their use may contribute to breast cancer risk. Results of the few previous studies on this topic are inconsistent. We assessed the relation of hair relaxer and leave-in conditioner use to breast cancer incidence in the Black Women's Health Study, a nationwide prospective study of Black women. Among 50 543 women followed from 1997 to 2017, 2311 incident breast cancers occurred. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression for breast cancer overall and by estrogen receptor (ER) status. For heavy use (≥15 years of use for ≥7 times/year) of hair relaxers relative to never/light use (<4 years, no more than 1-2 times/year), the multivariable HR for breast cancer overall was 1.13 (95%CI: 0.96-1.33). Duration, frequency, age at first use and number of scalp burns were not associated with overall breast cancer risk. For heavy use of hair relaxers containing lye, the corresponding HR for ER+ breast cancer was 1.32 (95% CI: 0.97, 1.80); there was no association for non-lye products. There was no association of conditioner use and breast cancer. Results of this study were largely null, but there was some evidence that heavy use of lye-containing hair relaxers may be associated with increased risk of ER+ breast cancer. Consistent results from several studies are needed before it can be concluded that use of certain hair relaxers impacts breast cancer development., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Air pollution contains numerous carcinogens and endocrine disruptors which may be relevant for breast cancer. Previous research has predominantly been conducted in White women; however, Black women may have higher air pollution exposure due to geographic and residential factors., Objective: We evaluated the association between air pollution and breast cancer risk in a large prospective population of Black women., Methods: We estimated annual average ambient levels of particulate matter <2.5 μm (PM 2.5 ), nitrogen dioxide (NO 2 ) and ozone (O 3 ) at the 1995 residence of 41,317 participants in the Black Women's Health Study who resided in 56 metropolitan areas across the United States. Cox proportional hazards regression was used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for an interquartile range (IQR) increase in each pollutant. We evaluated whether the association varied by menopausal status, estrogen receptor (ER) status of the tumor and geographic region of residence., Results: With follow-up through 2015 (mean = 18.3 years), 2146 incident cases of breast cancer were confirmed. Higher exposure to NO 2 or O 3 was not associated with a higher risk of breast cancer. For PM 2.5 , although we observed no association overall, there was evidence of modification by geographic region for both ER- (p for heterogeneity = 0.01) and premenopausal breast cancer (p for heterogeneity = 0.01). Among women living in the Midwest, an IQR increase in PM 2.5 (2.87 μg/m 3 ), was associated with a higher risk of ER- (HR = 1.53, 95% CI: 1.07-2.19) and premenopausal breast cancer (HR = 1.32, 95% CI: 1.03-1.71). In contrast, among women living in the South, PM 2.5 was inversely associated with both ER- (HR = 0.74, 95% CI: 0.56-0.97) and premenopausal breast cancer risk (HR = 0.75, 95% CI: 0.62-0.91)., Discussion: Overall, we observed no association between air pollution and increased breast cancer risk among Black women, except perhaps among women living in the Midwestern US., (Published by Elsevier Inc.)

Background: Use of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) has been hypothesized to be associated with reduced risk of breast cancer; however, results of epidemiological studies have been mixed. Few studies have investigated these associations among African American women., Methods: To assess the relation of aspirin use to risk of breast cancer in African American women, we conducted a prospective analysis within the Black Women's Health Study, an ongoing nationwide cohort study of 59,000 African American women. On baseline and follow-up questionnaires, women reported regular use of aspirin (defined as use at least 3 days per week) and years of use. During follow-up from 1995 through 2017, 1919 invasive breast cancers occurred, including 1112 ER+, 569 ER-, and 284 triple-negative (TN) tumors. We used age-stratified Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations of aspirin use with risk of ER+, ER-, and TN breast cancer, adjusted for established breast cancer risk factors., Results: Overall, the HR for current regular use of aspirin relative to non-use was 0.92 (95% CI 0.81, 1.04). For ER+, ER-, and TN breast cancer, corresponding HRs were 0.98 (0.84, 1.15), 0.81 (0.64, 1.04), and 0.70 (0.49, 0.99), respectively., Conclusions: Our findings with regard to ER- and TN breast cancer are consistent with hypothesized inflammatory mechanisms of ER- and TN breast cancer, rather than hormone-dependent pathways. Aspirin may represent a potential opportunity for chemoprevention of ER- and TN breast cancer.

Background: Compared to U.S. white women, African American women are more likely to die from ductal carcinoma in situ (DCIS). Elucidation of risk factors for DCIS in African American women may provide opportunities for risk reduction., Methods: We used data from three epidemiologic studies in the African American Breast Cancer Epidemiology and Risk Consortium to study risk factors for estrogen receptor (ER) positive DCIS (488 cases; 13,830 controls). Results were compared to associations observed for ER+ invasive breast cancer (n = 2,099)., Results: First degree family history of breast cancer was associated with increased risk of ER+ DCIS [odds ratio (OR): 1.69, 95% confidence interval (CI): 1.31, 2.17]. Oral contraceptive use within the past 10 years (vs. never) was also associated with increased risk (OR: 1.43, 95%CI: 1.03, 1.97), as was late age at first birth (≥25 years vs. <20 years) (OR: 1.26, 95%CI: 0.96, 1.67). Risk was reduced in women with older age at menarche (≥15 years vs. <11 years) (OR: 0.62, 95%CI: 0.42, 0.93) and higher body mass index (BMI) in early adulthood (≥25 vs. <20 kg/m 2 at age 18 or 21) (OR: 0.75, 95%CI: 0.55, 1.01). There was a positive association of recent BMI with risk in postmenopausal women only. In general, associations of risk factors for ER+ DCIS were similar in magnitude and direction to those for invasive ER+ breast cancer., Conclusions: Our findings suggest that most risk factors for invasive ER+ breast cancer are also associated with increased risk of ER+ DCIS among African American women., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Circadian misalignment may increase the risk of developing hepatocellular carcinoma (HCC). The aim of this study was to examine the association between distance from time zone meridian, a proxy for circadian misalignment, and HCC risk in the United States adjusting for known HCC risk factors. Methods: Surveillance, Epidemiology, and End Results (SEER) provided information on 56,347 HCC cases diagnosed between 2000 and 2014 from 16 population-based cancer registries in the United States. Distance from time zone meridian was estimated using the location of each SEER county's Center of Population in a geographic information system. Poisson regression with robust variance estimation was used to calculate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the association between distance from time zone meridian and HCC risk adjusting for individual-level age at diagnosis, sex, race/ethnicity, year of diagnosis, SEER registry, and county-level prevalence of health conditions, lifestyle factors, shift work occupation, socioeconomic status, and demographic and environmental factors. Results: A 5-degree increase in longitude moving east to west within a time zone was associated with a statistically significant increased risk for HCC (IRR, 1.07; 95% CI, 1.01-1.14, P = 0.03). A statistically significant positive association was observed among those <65 years old, while no association was observed among individuals ≥65 years old ( P for interaction Circadian misalignment from residing in the western region of a time zone may impact hepatocarcinogenesis. Conclusions: Circadian misalignment from residing in the western region of a time zone may impact hepatocarcinogenesis. Impact: Circadian misalignment may be an independent risk factor for HCC. Cancer Epidemiol Biomarkers Prev; 27(7); 719-27. ©2018 AACR ., (©2018 American Association for Cancer Research.)

Purpose: To conduct the first epidemiologic study prospectively examining the association between particulate matter air pollution < 2.5 µm in diameter (PM 2.5 ) exposure and hepatocellular carcinoma (HCC) risk in the U.S., Methods: Surveillance, Epidemiology, and End Results (SEER) provided information on HCC cases diagnosed between 2000 and 2014 from 16 population-based cancer registries across the U.S. Ambient PM 2.5 exposure was estimated by linking the SEER county with a spatial PM 2.5 model using a geographic information system. Poisson regression with robust variance estimation was used to calculate incidence rate ratios and 95% confidence intervals (CIs) for the association between ambient PM 2.5 exposure per 10 µg/m 3 increase and HCC risk adjusting for individual-level age at diagnosis, sex, race, year of diagnosis, SEER registry, and county-level information on health conditions, lifestyle, demographic, socioeconomic, and environmental factors., Results: Higher levels of ambient PM 2.5 exposure were associated with a statistically significant increased risk for HCC (n = 56,245 cases; adjusted IRR per 10 µg/m 3 increase = 1.26, 95% CI 1.08, 1.47; p < 0.01)., Conclusions: If confirmed in studies with individual-level PM 2.5 exposure and risk factor information, these results suggest that ambient PM 2.5 exposure may be a risk factor for HCC in the U.S.

Prior research suggests that several endogenous hormones in premenopausal women are associated with breast cancer risk; however, few studies have evaluated associations of endogenous hormones with mammographic density (MD) in premenopausal women. We conducted a cross-sectional study of plasma hormone levels in relation to MD among 634 cancer-free premenopausal women in the Nurses' Health Study II. We measured percent MD from screening mammograms using a computer-assisted method. We assayed estradiol, estrone, and estrone sulfate in blood samples timed in early follicular and mid-luteal phases of the menstrual cycle as well as testosterone, androstenedione, progesterone, dehydroepiandrosterone (DHEA), DHEA sulfate, sex hormone-binding globulin (SHBG), and anti-Müllerian hormone in luteal or untimed samples. We used multivariable linear regression to quantify the association of %MD with quartiles of each hormone, adjusting for age, body mass index, and breast cancer risk factors. Women in the highest quartile of follicular estradiol levels had significantly greater %MD compared to those in the lowest quartile [difference, 6.7 percentage points; 95% confidence interval (CI) 2.2, 11.3; p-trend < 0.001]. Similar associations were observed for follicular free estradiol but not luteal-phase estradiol. Also, women in the top (vs. bottom) quartile of free testosterone had significantly lower %MD (difference, - 4.7; 95% CI - 8.7, - 0.8; p-trend = 0.04). Higher SHBG was significantly associated with higher percent MD (difference, 4.8; 95% CI 1.1, 8.6; p-trend = 0.002). Percent MD was not strongly associated with other measured hormones. Results were similar in analyses that excluded women with anovulatory cycles. Our findings suggest that follicular estradiol and SHBG may play an important role in premenopausal percent MD.

Epidemiologic evidence for an association between plasma 25-hydroxyvitamin D [25(OH)D] and breast cancer is inconsistent. Data are especially limited for premenopausal women and for associations with mammographic density. To test the hypothesis that plasma concentration of 25(OH)D is associated with mammographic density, we conducted a cross-sectional study among 835 premenopausal women in the Nurses' Health Studies. We measured 25(OH)D in blood samples and used multivariable linear regression to quantify the association of average percent density by quartile of plasma 25(OH)D. In a nested case-control analysis including 493 breast cancer cases, we evaluated risk of breast cancer associated with vitamin D status within tertiles of mammographic density. Women in the top quartile of plasma 25(OH)D levels had an average percent breast density 5.2 percentage points higher than women in the bottom quartile (95 % confidence interval: 1.8, 8.7; P trend <0.01), after adjusting for predictors of 25(OH)D and established breast cancer risk factors. Plasma 25(OH)D concentration was significantly inversely associated with breast cancer risk among women with high mammographic density (P trend < 0.01) but not among women in lower tertiles of mammographic density (P-interaction < 0.01). These results do not support the hypothesis that vitamin D is inversely associated with percent mammographic density in premenopausal women. There was evidence that the association between premenopausal 25(OH)D and breast cancer risk varies by mammographic density, with an inverse association apparent only among women with high mammographic density.

Objective: To examine the association between ultraviolet-B (UV-B) light exposure and rheumatoid arthritis (RA) risk among women in two large prospective cohort studies, the Nurses' Health Study (NHS) and the Nurses' Health Study II (NHSII)., Methods: A total of 106 368 women from NHS, aged 30-55 years in 1976, and 115 561 women from NHSII, aged 25-42 in 1989, were included in the analysis. We identified women with incident RA from the start of each cohort until 2008 (NHS) and 2009 (NHSII). Cumulative average UV-B flux, a composite measure of ambient UV exposure based on latitude, altitude and cloud cover, was estimated according to state of residence and categorised as low, medium or high. Estimates of UV-B at birth and age 15 years were also examined. We used multivariable-adjusted Cox proportional hazards models to estimate HR and 95% CI., Results: 1314 incident RA cases were identified in total. Among NHS participants, higher cumulative average UV-B exposure was associated with decreased RA risk; those in the highest versus lowest category had a 21% decreased RA risk (HR (95% CI); 0.79 (0.66 to 0.94)). UV-B was not associated with RA risk among younger women in NHSII (1.12 (0.87 to 1.44)). Results were similar for UV-B at birth and at age 15., Conclusions: These results suggest that ambient UV-B exposure is associated with a lower RA risk in NHS, but not NHSII. Differences in sun-protective behaviours (eg, greater use of sun block in younger generations) may explain the disparate results.

Background: Despite safety reports of the artificial sweetener aspartame, health-related concerns remain., Objective: We prospectively evaluated whether the consumption of aspartame- and sugar-containing soda is associated with risk of hematopoetic cancers., Design: We repeatedly assessed diet in the Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS). Over 22 y, we identified 1324 non-Hodgkin lymphomas (NHLs), 285 multiple myelomas, and 339 leukemias. We calculated incidence RRs and 95% CIs by using Cox proportional hazards models., Results: When the 2 cohorts were combined, there was no significant association between soda intake and risks of NHL and multiple myeloma. However, in men, ≥1 daily serving of diet soda increased risks of NHL (RR: 1.31; 95% CI: 1.01, 1.72) and multiple myeloma (RR: 2.02; 95% CI: 1.20, 3.40) in comparison with men who did not consume diet soda. We observed no increased risks of NHL and multiple myeloma in women. We also observed an unexpected elevated risk of NHL (RR: 1.66; 95% CI: 1.10, 2.51) with a higher consumption of regular, sugar-sweetened soda in men but not in women. In contrast, when sexes were analyzed separately with limited power, neither regular nor diet soda increased risk of leukemia but were associated with increased leukemia risk when data for men and women were combined (RR for consumption of ≥1 serving of diet soda/d when the 2 cohorts were pooled: 1.42; 95% CI: 1.00, 2.02)., Conclusion: Although our findings preserve the possibility of a detrimental effect of a constituent of diet soda, such as aspartame, on select cancers, the inconsistent sex effects and occurrence of an apparent cancer risk in individuals who consume regular soda do not permit the ruling out of chance as an explanation.

Vital statistics for the lymphoid malignancies obtained from the Surveillance, Epidemiology and End Results (SEER) Program have seldom been directly compared to data from alternative national databases. While SEER is recognized as the standard, some lymphoid malignancies-especially the chronic ones--may be underreported. We compared the incidence, all-cause and cause-specific mortality for Hodgkin's lymphoma (HL), non-Hodgkin's lymphoma (NHL), multiple myeloma (MM) and chronic lymphocytic leukaemia (CLL) in SEER to that in the Nurses' Health Study (NHS), a national cohort study of 121,700 female registered nurses, matching for age and race. In over 2.5 million person-years, the incidence of HL was the same as in SEER (SIR=1.01 [0.75, 1.26]), while the incidence of NHL, CLL and MM were slightly higher. All-cause mortality was lower for the lymphoid malignancies except for MM, which was the same; there were no differences in cause-specific mortality, except for MM (HR=1.26 [1.07, 1.48]). Our analysis suggests that, at least among white women, SEER is a reliable data source with respect to lymphoid malignancies., (© 2009 John Wiley & Sons, Ltd.)