Reproductive factors and mammographic density within the International Consortium of Mammographic Density: A cross-sectional study.

BACKGROUND: Elevated mammographic density (MD) for a woman's age and body mass index (BMI) is an established breast cancer risk factor. The relationship of parity, age at first birth, and breastfeeding with MD is less clear. We examined the associations of these factors with MD within the International Consortium of Mammographic Density (ICMD). METHODS: ICMD is a consortium of 27 studies with pooled individual-level epidemiological and MD data from 11,755 women without breast cancer aged 35-85 years from 22 countries, capturing 40 country-& ethnicity-specific population groups. MD was measured using the area-based tool Cumulus. Meta-analyses across population groups and pooled analyses were used to examine linear regression associations of square-root (√) transformed MD measures (percent MD (PMD), dense area (DA), and non-dense area (NDA)) with parity, age at first birth, ever/never breastfed and lifetime breastfeeding duration. Models were adjusted for age at mammogram, age at menarche, BMI, menopausal status, use of hormone replacement therapy, calibration method, mammogram view and reader, and parity and age at first birth when not the association of interest. RESULTS: Among 10,988 women included in these analyses, 90.1% (n = 9,895) were parous, of whom 13% (n = 1,286) had ≥ five births. The mean age at first birth was 24.3 years (Standard deviation = 5.1). Increasing parity (per birth) was inversely associated with √PMD (ß: - 0.05, 95% confidence interval (CI): - 0.07, - 0.03) and √DA (ß: - 0.08, 95% CI: - 0.12, - 0.05) with this trend evident until at least nine births. Women who were older at first birth (per five-year increase) had higher √PMD (ß:0.06, 95% CI:0.03, 0.10) and √DA (ß:0.06, 95% CI:0.02, 0.10), and lower √NDA (ß: - 0.06, 95% CI: - 0.11, - 0.01). In stratified analyses, this association was only evident in women who were post-menopausal at MD assessment. Among parous women, no associations were found between ever/never breastfed or lifetime breastfeeding duration (per six-month increase) and √MD. CONCLUSIONS: Associations with higher parity and older age at first birth with √MD were consistent with the direction of their respective associations with breast cancer risk. Further research is needed to understand reproductive factor-related differences in the composition of breast tissue and their associations with breast cancer risk.

Sexual Orientation-Related Disparities in Neonatal Outcomes.

OBJECTIVE: To evaluate whether disparities exist in adverse neonatal outcomes among the offspring of lesbian, gay, bisexual, and other sexually minoritized (LGB+) birthing people. METHODS: We used longitudinal data from 1995 to 2017 from the Nurses' Health Study II, a cohort of nurses across the United States. We restricted analyses to those who reported live births (N=70,642) in the 2001 or 2009 lifetime pregnancy questionnaires. Participants were asked about sexual orientation identity (current and past) and same-sex attractions and partners. We examined preterm birth, low birth weight, and macrosomia among 1) completely heterosexual; 2) heterosexual with past same-sex attractions, partners, or identity; 3) mostly heterosexual; 4) bisexual; and 5) lesbian or gay participants. We used log-binomial models to estimate risk ratios for each outcome and weighted generalized estimating equations to account for multiple pregnancies per person over time and informative cluster sizes. RESULTS: Compared with completely heterosexual participants, offspring born to parents in all LGB+ groups combined (groups 2-5) had higher estimated risks of preterm birth (risk ratio 1.22, 95% CI, 1.15-1.30) and low birth weight (1.27, 95% CI, 1.15-1.40) but not macrosomia (0.98, 95% CI, 0.94-1.02). In the subgroup analysis, risk ratios were statistically significant for heterosexual participants with past same-sex attractions, partners, or identity (preterm birth 1.25, 95% CI, 1.13-1.37; low birth weight 1.32, 95% CI, 1.18-1.47). Risk ratios were elevated but not statistically significant for lesbian or gay participants (preterm birth 1.37, 95% CI, 0.98-1.93; low birth weight 1.46, 95% CI, 0.96-2.21) and bisexual participants (preterm birth 1.29, 95% CI, 0.85-1.93; low birth weight 1.24, 95% CI, 0.74-2.08). CONCLUSION: The offspring of LGB+ birthing people experience adverse neonatal outcomes, specifically preterm birth and low birth weight. These findings highlight the need to better understand health risks, social inequities, and health care experiences that drive these adverse outcomes.

Germline polygenic risk scores are associated with immune gene expression signature and immune cell infiltration in breast cancer.

The tumor immune microenvironment (TIME) plays key roles in tumor progression and response to immunotherapy. Previous studies have identified individual germline variants associated with differences in TIME. Here, we hypothesize that common variants associated with breast cancer risk or cancer-related traits, represented by polygenic risk scores (PRSs), may jointly influence immune features in TIME. We derived 154 immune traits from bulk gene expression profiles of 764 breast tumors and 598 adjacent normal tissue samples from 825 individuals with breast cancer in the Nurses' Health Study (NHS) and NHSII. Immunohistochemical staining of four immune cell markers were available for a subset of 205 individuals. Germline PRSs were calculated for 16 different traits including breast cancer, autoimmune diseases, type 2 diabetes, ages at menarche and menopause, body mass index (BMI), BMI-adjusted waist-to-hip ratio, alcohol intake, and tobacco smoking. Overall, we identified 44 associations between germline PRSs and immune traits at false discovery rate q < 0.25, including 3 associations with q < 0.05. We observed consistent inverse associations of inflammatory bowel disease (IBD) and Crohn disease (CD) PRSs with interferon signaling and STAT1 scores in breast tumor and adjacent normal tissue; these associations were replicated in a Norwegian cohort. Inverse associations were also consistently observed for IBD PRS and B cell abundance in normal tissue. We also observed positive associations between CD PRS and endothelial cell abundance in tumor. Our findings suggest that the genetic mechanisms that influence immune-related diseases are also associated with TIME in breast cancer.

Analysis of more than 400,000 women provides case-control evidence for BRCA1 and BRCA2 variant classification.

Clinical genetic testing identifies variants causal for hereditary cancer, information that is used for risk assessment and clinical management. Unfortunately, some variants identified are of uncertain clinical significance (VUS), complicating patient management. Case-control data is one evidence type used to classify VUS, and previous findings indicate that case-control likelihood ratios (LRs) outperform odds ratios for variant classification. As an initiative of the Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) Analytical Working Group we analyzed germline sequencing data of BRCA1 and BRCA2 from 96,691 female breast cancer cases and 303,925 unaffected controls from three studies: the BRIDGES study of the Breast Cancer Association Consortium, the Cancer Risk Estimates Related to Susceptibility consortium, and the UK Biobank. We observed 11,227 BRCA1 and BRCA2 variants, with 6,921 being coding, covering 23.4% of BRCA1 and BRCA2 VUS in ClinVar and 19.2% of ClinVar curated (likely) benign or pathogenic variants. Case-control LR evidence was highly consistent with ClinVar assertions for (likely) benign or pathogenic variants; exhibiting 99.1% sensitivity and 95.4% specificity for BRCA1 and 92.2% sensitivity and 86.6% specificity for BRCA2. This approach provides case-control evidence for 785 unclassified variants, that can serve as a valuable element for clinical classification.

History of infertility and anti-Müllerian hormone levels among participants in the Nurses' Health Study II.

OBJECTIVES: To better understand whether history of infertility is associated with anti-Müllerian hormone (AMH) levels later in life, outside of reproduction. METHODS: Among 1,758 premenopausal women in the Nurses' Health Study II with measured AMH, we used multivariable generalized linear models to compare log-transformed plasma AMH for women with a history of infertility compared with fertile women. We investigated AMH levels by cause of infertility and effect modification by menstrual cycle regularity. Lastly, we investigated AMH levels by history of primary and secondary infertility and age at reported infertility. RESULTS: Mean age at blood collection was 40 years. We observed no association between overall history of infertility and AMH levels (% difference AMH: -8.1% [CI, -19.4 to 4.8]). The association between overall infertility and AMH was strongest among women who first reported infertility at >30 years (-17.7% [CI, -32.1 to -0.3]). CONCLUSIONS: Overall, we observed no association between the history of infertility and AMH levels later in life. However, specific subgroups of women with a history of infertility may have lower AMH levels throughout life compared with fertile women. This association was observed among subgroups, such as those who first experienced infertility at >30 years. These findings have implications for mechanisms through which infertility may be associated with premature menopause and chronic disease risk.

Circulating Estrogen Metabolites and Risk of Breast Cancer among Postmenopausal Women in the Nurses' Health Study.

BACKGROUND: Estradiol and estrone are well-established risk factors for postmenopausal breast cancer (BC). Experimental evidence suggests that specific estrogen metabolites, produced via irreversible hydroxylation of estrone and estradiol at the 2- or 16-position may independently influence carcinogenesis. METHODS: We performed a nested case-control study of BC (328 BC cases; 639 controls) among postmenopausal women within the Nurses' Health Study (NHS)to examine the role of estrogens and estrogen metabolites (jointly referred to as EM). Plasma concentrations of each EM (unconjugated+conjugated forms) were measured by liquid chromatography-tandem mass spectrometry. Multivariable conditional logistic regression, adjusting for BC risk factors, estimated relative risks (RR) and 95% confidence intervals (CI) of BC across quintiles of individual EM, EM pathways, and pathway ratios. Associations by estrogen/progesterone receptor (ER/PR) status were analyzed by unconditional logistic regression. RESULTS: Estradiol and estrone were strongly associated with increased BC risk [estradiol: RRQ5v.Q1 (95% CI)=2.64 (1.64-4.26), estrone: 2.78 (1.74-4.45); both p-trends<0.001]. The 2-hydroxylation pathway was strongly associated with risk [RRQ5v.Q1=3.09 (1.81-5.27), p-trend<0.001], and remained so after adjusting for unconjugated estradiol [RRQ5v.Q1=2.23 (1.25-3.96), p-trend=0.01]. While the 16-hydroxylation pathway was modestly associated with risk [RRQ5v.Q1=1.62 (1.03-2.54), p-trend=0.01], the association was attenuated after unconjugated estradiol adjustment [RRQ5v.Q1=1.24 (0.77-1.99), p-trend=0.19]. Similar positive associations with the 2-pathway and 16-pathway were observed for ER+/PR+ and ER-/PR- tumors. CONCLUSIONS: In this cohort of postmenopausal women, 2-hydroxylation of estrone and estradiol was associated with increased BC risk, independent of unconjugated estradiol. IMPACT: These results highlight the need to revisit the role of estrogen metabolism in BC etiology and prevention.

Pre-Diagnostic Amino Acid Metabolites and Risk of Gout, Accounting for Serum Urate: Prospective Cohort Study and Mendelian Randomization.

OBJECTIVES: Our objective was to prospectively investigate pre-diagnostic population-based metabolome for risk of hospitalized gout (i.e., most accurate, severe, and costly cases), accounting for serum urate. METHODS: We conducted pre-diagnostic metabolome-wide analyses among 249,677 UK Biobank participants with NMR metabolomic profiling (N=168 metabolites, including eight amino acids) from baseline blood samples (2006-2010), without a history of gout. We calculated multivariable hazard ratios (HRs) for incident hospitalized gout, before and after adjusting for serum urate levels; we included non-hospitalised incident gout cases in a sensitivity analysis. Potential causal effects were evaluated with two-sample Mendelian randomization. RESULTS: Correcting for multiple testing, 107 metabolites were associated with incidence of hospitalized gout (N=2735) before urate adjustment, including glycine and glutamine (inversely; HR=0.64 [95% CI: 0.54, 0.75], P=8.3x10-8 and HR=0.69 [0.61, 0.78], P=3.3x10-9 between extreme quintiles, respectively), and glycoprotein acetyls (GlycA; HR=2.48 [2.15, 2.87], P=1.96x10-34). Associations remained significant and directionally-consistent following urate adjustment (HR=0.83 [0.70, 0.98], 0.86 [0.76, 0.98], 1.41 [1.21, 1.63] between extreme quintiles), respectively; corresponding HR per SD were 0.91 (0.86, 0.97), 0.94 (0.91, 0.98), and 1.10 (1.06, 1.14). Findings persisted when including non-hospitalised incident gout cases. Mendelian randomization corroborated their potential causal role on hyperuricemia or gout risk; with change in urate levels of -0.05 mg/dL (-0.08, -0.01), and -0.12 mg/dL (-0.22, -0.03), per SD of glycine and glutamine, respectively, and ORs 0.94 (0.88, 1.00), and 0.81 (0.67, 0.97), for gout. CONCLUSION: These prospective findings with causal implications could lead to biomarker-based risk prediction and potential supplementation-based interventions with glycine or glutamine.

Pet Attachment and Anxiety and Depression in Middle-Aged and Older Women.

Importance: Understanding how attachment to pets can alleviate depression and anxiety offers valuable insights for developing preventive and therapeutic strategies, particularly for those with insecure attachment styles from childhood trauma. Objective: To determine if a close bond with a pet is associated with reduced depression and anxiety, especially among women who experienced childhood abuse. Design, Setting, and Participants: This cross-sectional study involved women who voluntarily enrolled in the Mind Body Study (MBS), a substudy of the Nurses' Health Study II (NHS2) focusing on psychosocial factors. Women reporting childhood abuse were oversampled to capture their psychosocial distress in adulthood. MBS participants were invited to complete comprehensive online questionnaires, which were administered twice (March 2013 and February 2014). Exposure: Pet attachment measured by Lexington Attachment to Pets Scale (LAPS). Main Outcomes and Measures: Levels of depression and anxiety (10-item Centre for Epidemiologic Studies Depression Scale [CESD-10]; Kessler Psychological Distress Scale [K6]; 7-item Generalized Anxiety Disorder scale [GAD-7]; Crown Crisp Experiential Index phobic anxiety subscale [CCI]), considered individually and combined into an overall z-score measure of anxiety and depression symptoms. Results: A total of 214 women (mean [SD] age, 60.8 [3.9] years) were included; 156 women (72.6%) reported a history of childhood abuse. Of 688 invited MBS participants in 2013, 293 (42.6%) expressed interest; there were 228 completed questionnaires (response rate, 77.8%) in 2013 and 208 questionnaires (response rate, 71.0%) in 2014. LAPS scores were provided by 140 participants (65.4%), 78 (55.7%) for dogs and 46 (32.9%) for cats. Overall higher pet attachment on the LAPS score was significantly associated with lower GAD-7 scores (ß = -0.17; 95% CI, -0.29 to -0.06), but there was no association for phobic anxiety or depression. There were no statistically significant associations between cat attachment and depression or anxiety. Higher dog attachment was associated with significantly lower scores in depression (CESD-10: ß, -0.47; 95% CI, -0.68 to -0.26; K6: ß = -0.42; 95% CI, -0.54 to -0.31), generalized anxiety (GAD-7: ß = -0.47; 95% CI, -0.65 to -0.3), and the overall measure of anxiety and depression (z score: ß = -0.12; 95% CI, -0.17 to -0.08), but there was no association between dog attachment and phobic anxiety (CCI: ß = -0.08; 95% CI, -0.24 to 0.09). All effect sizes for associations were higher when analyses were restricted to women with a history of childhood abuse. Conclusions and relevance: In this explorative cross-sectional study, strong attachment to pets, especially dogs, was associated with lower anxiety and depression symptoms. The favorable association was particularly apparent in women with a history of childhood abuse.

Integration of epidemiological and blood biomarker analysis links haem iron intake to increased type 2 diabetes risk.

Dietary haem iron intake is linked to an increased risk of type 2 diabetes (T2D), but the underlying plasma biomarkers are not well understood. We analysed data from 204,615 participants (79% females) in three large US cohorts over up to 36 years, examining the associations between iron intake and T2D risk. We also assessed plasma metabolic biomarkers and metabolomic profiles in subsets of 37,544 (82% females) and 9,024 (84% females) participants, respectively. Here we show that haem iron intake but not non-haem iron is associated with a higher T2D risk, with a multivariable-adjusted hazard ratio of 1.26 (95% confidence interval 1.20-1.33; P for trend <0.001) comparing the highest to the lowest quintiles. Haem iron accounts for significant proportions of the T2D risk linked to unprocessed red meat and specific dietary patterns. Increased haem iron intake correlates with unfavourable plasma profiles of insulinaemia, lipids, inflammation and T2D-linked metabolites. We also identify metabolites, including L-valine and uric acid, potentially mediating the haem iron-T2D relationship, highlighting their pivotal role in T2D pathogenesis.

Sexual orientation disparities in gestational diabetes and hypertensive disorders of pregnancy.

BACKGROUND: Sexual minority (SM) individuals (e.g., those with same-sex attractions/partners or who identify as lesbian/gay/bisexual) experience a host of physical and mental health disparities. However, little is known about sexual orientation-related disparities in gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP; gestational hypertension [gHTN] and preeclampsia). OBJECTIVE: To estimate disparities in GDM, gHTN and preeclampsia by sexual orientation. METHODS: We used data from the Nurses' Health Study II-a cohort of nurses across the US enrolled in 1989 at 25-42 years of age-restricted to those with pregnancies ≥20 weeks gestation and non-missing sexual orientation data (63,518 participants; 146,079 pregnancies). Our primary outcomes were GDM, gHTN and preeclampsia, which participants reported for each of their pregnancies. Participants also reported their sexual orientation identity and same-sex attractions/partners. We compared the risk of each outcome in pregnancies among heterosexual participants with no same-sex experience (reference) to those among SM participants overall and within subgroups: (1) heterosexual with same-sex experience, (2) mostly heterosexual, (3) bisexual and (4) lesbian/gay participants. We used modified Poisson models to estimate risk ratios (RR) and 95% confidence intervals (CI), fit via weighted generalised estimating equations, to account for multiple pregnancies per person over time and informative cluster sizes. RESULTS: The overall prevalence of each outcome was ≤5%. Mostly heterosexual participants had a 31% higher risk of gHTN (RR 1.31, 95% CI 1.03, 1.66), and heterosexual participants with same-sex experience had a 31% higher risk of GDM (RR 1.31, 95% CI 1.13, 1.50), compared to heterosexual participants with no same-sex experience. The magnitudes of the risk ratios were high among bisexual participants for gHTN and preeclampsia and among lesbian/gay participants for gHTN. CONCLUSIONS: Some SM groups may be disparately burdened by GDM and HDP. Elucidating modifiable mechanisms (e.g., structural barriers, discrimination) for reducing adverse pregnancy outcomes among SM populations is critical.

All-cause and cause-specific mortality risk and loss in life expectancy associated with incident type 2 diabetes onset age and duration.

BACKGROUND: Evidence on type 2 diabetes onset age and duration on mortality risk has been limited by short follow-up, inadequate control for confounding, missing repeated measurements, and inability to cover the full range of onset age, duration, and major causes of death. Moreover, scarce data dissect how type 2 diabetes onset age and duration shape life expectancy. METHODS: We evaluate prospectively these topics based on 270,075 eligible participants in the Nurses' Health Studies and Health Professionals Follow-up Study, leveraging repeated measurements throughout up to 40 years of follow-up. Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: In fully adjusted analyses, incident early onset type 2 diabetes (diagnosed <40 years of age) was associated with significantly higher mortality from all-causes (HR, 95% CI was 3.16, 2.64-3.79; vs. individuals without type 2 diabetes), cardiovascular disease (6.56, 4.27-10.1), respiratory disease (3.43, 1.38-8.51), neurodegenerative disease (5.13, 2.09-12.6), and kidney disease (8.55, 1.98-36.9). The relative risk elevations declined dramatically with each higher decade of age at diagnosis for deaths from most of these causes, though the absolute risk difference increased continuously. A substantially higher cumulative incidence of mortality and a greater loss in life expectancy were associated with younger age at type 2 diabetes diagnosis. Longer disease duration was associated with generally higher relative and absolute risk of mortality. CONCLUSION: Early onset of type 2 diabetes and longer disease duration are associated with substantially increased risk of all-cause and cause-specific mortality and greater loss in life expectancy.

Alcohol intake and endogenous sex hormones in women: Meta-analysis of cohort studies and Mendelian randomization.

BACKGROUND: The mechanisms underlying alcohol-induced breast carcinogenesis are not fully understood but may involve hormonal changes. METHODS: Cross-sectional associations were investigated between self-reported alcohol intake and serum or plasma concentrations of estradiol, estrone, progesterone (in premenopausal women only), testosterone, androstenedione, dehydroepiandrosterone sulfate, and sex hormone binding globulin (SHBG) in 45 431 premenopausal and 173 476 postmenopausal women. Multivariable linear regression was performed separately for UK Biobank, European Prospective Investigation into Cancer and Nutrition, and Endogenous Hormones and Breast Cancer Collaborative Group, and meta-analyzed the results. For testosterone and SHBG, we also conducted Mendelian randomization and colocalization using the ADH1B (alcohol dehydrogenase 1B) variant (rs1229984). RESULTS: Alcohol intake was positively, though weakly, associated with all hormones (except progesterone in premenopausal women), with increments in concentrations per 10 g/day increment in alcohol intake ranging from 1.7% for luteal estradiol to 6.6% for postmenopausal dehydroepiandrosterone sulfate. There was an inverse association of alcohol with SHBG in postmenopausal women but a small positive association in premenopausal women. Two-sample randomization identified positive associations of alcohol intake with total testosterone (difference per 10 g/day increment: 4.1%; 95% CI, 0.6-7.6) and free testosterone (7.8%; 4.1-11.5), and an inverse association with SHBG (-8.1%; -11.3% to -4.9%). Colocalization suggested a shared causal locus at ADH1B between alcohol intake and higher free testosterone and lower SHBG (posterior probability for H4, 0.81 and 0.97, respectively). CONCLUSIONS: Alcohol intake was associated with small increases in sex hormone concentrations, including bioavailable fractions, which may contribute to its effect on breast cancer risk.

Association of early menarche with breast tumor molecular features and recurrence.

BACKGROUND: Early menarche is an established risk factor for breast cancer but its molecular contribution to tumor biology and prognosis remains unclear. METHODS: We profiled transcriptome-wide gene expression in breast tumors (N = 846) and tumor-adjacent normal tissues (N = 666) from women in the Nurses' Health Studies (NHS) to investigate whether early menarche (age < 12) is associated with tumor molecular and prognostic features in women with breast cancer. Multivariable linear regression and pathway analyses using competitive gene set enrichment analysis were conducted in both tumor and adjacent-normal tissue and externally validated in TCGA (N = 116). Subgroup analyses stratified on ER-status based on the tumor were also performed. PAM50 signatures were used for tumor molecular subtyping and to generate proliferation and risk of recurrence scores. We created a gene expression score using LASSO regression to capture early menarche based on 28 genes from FDR-significant pathways in breast tumor tissue in NHS and tested its association with 10-year disease-free survival in both NHS (N = 836) and METABRIC (N = 952). RESULTS: Early menarche was significantly associated with 369 individual genes in adjacent-normal tissues implicated in extracellular matrix, cell adhesion, and invasion (FDR ≤ 0.1). Early menarche was associated with upregulation of cancer hallmark pathways (18 significant pathways in tumor, 23 in tumor-adjacent normal, FDR ≤ 0.1) related to proliferation (e.g. Myc, PI3K/AKT/mTOR, cell cycle), oxidative stress (e.g. oxidative phosphorylation, unfolded protein response), and inflammation (e.g. pro-inflammatory cytokines IFN α and IFN γ ). Replication in TCGA confirmed these trends. Early menarche was associated with significantly higher PAM50 proliferation scores (ß = 0.082 [0.02-0.14]), odds of aggressive molecular tumor subtypes (basal-like, OR = 1.84 [1.18-2.85] and HER2-enriched, OR = 2.32 [1.46-3.69]), and PAM50 risk of recurrence score (ß = 4.81 [1.71-7.92]). Our NHS-derived early menarche gene expression signature was significantly associated with worse 10-year disease-free survival in METABRIC (N = 952, HR = 1.58 [1.10-2.25]). CONCLUSIONS: Early menarche is associated with more aggressive molecular tumor characteristics and its gene expression signature within tumors is associated with worse 10-year disease-free survival among women with breast cancer. As the age of onset of menarche continues to decline, understanding its relationship to breast tumor characteristics and prognosis may lead to novel secondary prevention strategies.

Differences in metabolomic profiles between Black and White women in the U.S.: Analyses from two prospective cohorts.

There is growing interest in incorporating metabolomics into public health practice. However, Black women are under-represented in many metabolomics studies. If metabolomic profiles differ between Black and White women, this under-representation may exacerbate existing Black-White health disparities. We therefore aimed to estimate metabolomic differences between Black and White women in the U.S. We leveraged data from two prospective cohorts: the Nurses' Health Study (NHS; n = 2077) and Women's Health Initiative (WHI; n = 2128). The WHI served as the replication cohort. Plasma metabolites (n = 334) were measured via liquid chromatography-tandem mass spectrometry. Observed metabolomic differences were estimated using linear regression and metabolite set enrichment analyses. Residual metabolomic differences in a hypothetical population in which the distributions of 14 risk factors were equalized across racial groups were estimated using inverse odds ratio weighting. In the NHS, Black-White differences were observed for most metabolites (75 metabolites with observed differences ≥ |0.50| standard deviations). Black women had lower average levels than White women for most metabolites (e.g., for N6, N6-dimethlylysine, mean Black-White difference = - 0.98 standard deviations; 95% CI: - 1.11, - 0.84). In metabolite set enrichment analyses, Black women had lower levels of triglycerides, phosphatidylcholines, lysophosphatidylethanolamines, phosphatidylethanolamines, and organoheterocyclic compounds, but higher levels of phosphatidylethanolamine plasmalogens, phosphatidylcholine plasmalogens, cholesteryl esters, and carnitines. In a hypothetical population in which distributions of 14 risk factors were equalized, Black-White metabolomic differences persisted. Most results replicated in the WHI (88% of 272 metabolites available for replication). Substantial differences in metabolomic profiles exist between Black and White women. Future studies should prioritize racial representation.

Identifying modifiable risk factors to prevent aggressive colorectal cancer.

It remains unclear if pre-diagnostic factors influence the developmental pathways of colorectal cancer (CRC) that could enhance tumor aggressiveness. This study used prospective data from 205,489 cancer-free US health professionals to investigate the associations of 31 known or putative risk factors with the risk of aggressive CRC. Tumor aggressiveness was characterized by three endpoints: aggressive CRC (cancer that causes death within 5 years of diagnosis), fatal CRC, and tumor stage at diagnosis. The data augmentation method was used to assess the difference in the associations between risk factors and endpoints. We documented 3201 CRC cases, of which 899 were aggressive. The protective associations of undergoing lower endoscopy (hazard ratios [HR] 0.43, 95% confidence interval (CI) 0.37, 0.49 for aggressive versus HR 0.61, 95% CI 0.56, 0.67 for non-aggressive) and regular use of aspirin (HR 0.70, 95% CI 0.61, 0.81 versus HR 0.84, 95% CI 0.77, 0.92) were stronger for aggressive than non-aggressive CRC (pHeterogeneity <0.05). Lower intake of whole grains or cereal fiber and greater dietary inflammatory potential were associated with a higher risk of aggressive but not non-aggressive CRC. The remaining risk factors showed comparable associations with aggressive CRC and non-aggressive CRC. Aggressive cases were more likely to have KRAS-mutated tumors but less likely to have distal or MSI-high tumors (p < .007). Similar results were observed for fatal CRC and advanced tumor stages at diagnosis. These findings provide initial evidence for the role of pre-diagnostic risk factors in the pathogenesis of aggressive CRC and suggest research priorities for preventive interventions.

Disparities in cancer incidence by sexual orientation.

INTRODUCTION: Cancer risk factors are more common among sexual minority populations (e.g., lesbian, bisexual) than their heterosexual peers, yet little is known about cancer incidence across sexual orientation groups. METHODS: The 1989-2017 data from the Nurses' Health Study II, a longitudinal cohort of female nurses across the United States, were analyzed (N = 101,543). Sexual orientation-related cancer disparities were quantified by comparing any cancer incidence among four sexual minority groups based on self-disclosure-(1) heterosexual with past same-sex attractions/partners/identity; (2) mostly heterosexual; (3) bisexual; and (4) lesbian women-to completely heterosexual women using age-adjusted incidence rate ratios (aIRR) calculated by the Mantel-Haenszel method. Additionally, subanalyses at 21 cancer disease sites (e.g., breast, colon/rectum) were conducted. RESULTS: For all-cancer analyses, there were no statistically significant differences in cancer incidence at the 5% type I error cutoff among sexual minority groups when compared to completely heterosexual women; the aIRR was 1.17 (95% CI,0.99-1.38) among lesbian women and 0.80 (0.58-1.10) among bisexual women. For the site-specific analyses, incidences at multiple sites were significantly higher among lesbian women compared to completely heterosexual women: thyroid cancer (aIRR, 1.87 [1.03-3.41]), basal cell carcinoma (aIRR, 1.85 [1.09-3.14]), and non-Hodgkin lymphoma (aIRR, 2.13 [1.10-4.12]). CONCLUSION: Lesbian women may be disproportionately burdened by cancer relative to their heterosexual peers. Sexual minority populations must be explicitly included in cancer prevention efforts. Comprehensive and standardized sexual orientation data must be systematically collected so nuanced sexual orientation-related cancer disparities can be accurately assessed for both common and rare cancers.

Recreational physical activity and breast cancer risk by menopausal status and tumor hormone receptor status: results from the Nurses' Health Studies.

PURPOSE: Physical activity is associated with lower breast cancer risk, especially in postmenopausal women. Associations in premenopausal women are less well established. METHODS: We evaluated recreational physical activity and breast cancer risk in the Nurses' Health Study (NHS) and NHSII (187,278 women; n = 12,785 breast cancers; follow-up: NHS = 1986-2016, NHSII = 1989-2017) by menopausal status and estrogen (ER) and progesterone (PR) receptor status. Physical activity was evaluated as updated cumulative average of metabolic equivalent of task (MET)-h/week. Cox proportional hazards models were used to estimate multivariable hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: Recreational physical activity was inversely associated with breast cancer risk in pre- and postmenopausal women. Higher activity levels were associated with lower risk of ER+/PR + breast cancer in both pre- and postmenopausal women (e.g., total recreational activity, ≥ 27 vs < 3 MET-h/week, premenopausal HR = 0.83, 95%CI = (0.70-0.99), postmenopausal HR = 0.86 (0.78-0.95); pheterogeneity = 0.97). Results were attenuated with adjustment for current body mass index (BMI) among postmenopausal, but not premenopausal, women (e.g., ≥ 27 vs < 3 MET-h/week, premenopausal HR = 0.83 (0.69-0.98); postmenopausal HR = 0.95 (0.85-1.05); pheterogeneity = 0.99). In analyses of moderate-vigorous activity and breast cancer risk, no heterogeneity by menopausal status was observed (phet ≥ 0.53; e.g., ≥ 27 vs < 3 MET-h/week, ER+/PR+, premenopausal HR = 0.88 (0.69-1.11); postmenopausal HR = 0.71 (0.58-0.88). No associations were observed for ER-/PR- disease. CONCLUSIONS: Recreational physical activity was associated with lower breast cancer risk in both pre- and postmenopausal women, supporting recreational physical activity as an accessible, modifiable exposure associated with reduced breast cancer risk regardless of menopausal status.

Maternal One-Carbon Nutrient Intake and Risk of Being Overweight or Obese in Their Offspring-A Transgenerational Prospective Cohort Study.

We aimed to investigate the associations between maternal intake of folate, vitamin B12, B6, B2, methionine, choline, phosphatidylcholine and betaine during the period surrounding pregnancy and offspring weight outcomes from birth to early adulthood. These associations were examined among 2454 mother-child pairs from the Nurses' Health Study II and Growing Up Today Study. Maternal energy-adjusted nutrient intakes were derived from food frequency questionnaires. Birth weight, body size at age 5 and repeated BMI measurements were considered. Overweight/obesity was defined according to the International Obesity Task Force (<18 years) and World Health Organization guidelines (18+ years). Among other estimands, we report relative risks (RRs) for offspring ever being overweight with corresponding 95% confidence intervals across quintiles of dietary factors, with the lowest quintile as the reference. In multivariate-adjusted models, higher maternal intakes of phosphatidylcholine were associated with a higher risk of offspring ever being overweight (RRQ5vsQ1 = 1.16 [1.01-1.33] p-trend: 0.003). The association was stronger among offspring born to mothers with high red meat intake (high red meat RRQ5vsQ1 = 1.50 [1.14-1.98], p-trend: 0.001; low red meat RRQ5vsQ1 = 1.05 [0.87-1.27], p-trend: 0.46; p-interaction = 0.13). Future studies confirming the association between a higher maternal phosphatidylcholine intake during pregnancy and offspring risk of being overweight or obese are needed.

Metabolomic signatures of inflammation and metabolic dysregulation in relation to colorectal cancer risk.

BACKGROUND: Inflammation and metabolic dysregulation are associated with increased risk of colorectal cancer (CRC); the underlying mechanisms are not fully understood. We characterized metabolomic signatures of inflammation and metabolic dysregulation and evaluated the association of the signatures and individual metabolites with CRC risk. METHODS: Among 684 incident CRC cases and 684 age-matched controls in the Nurses' Health Study (n = 818 women) and Health Professionals Follow-up Study (n = 550 men), we applied reduced rank and elastic net regression to 277 metabolites for markers of inflammation (C-reactive protein, interleukin 6, tumor necrosis factor receptor superfamily member 1B, and growth differentiation factor 15) or metabolic dysregulation (body mass index, waist circumference, C-peptide, and adiponectin) to derive metabolomic signatures. We evaluated the association of the signatures and individual metabolites with CRC using multivariable conditional logistic regression. All statistical tests were 2-sided. RESULTS: We derived a signature of 100 metabolites that explained 24% of variation in markers of inflammation and a signature of 73 metabolites that explained 27% of variation in markers of metabolic dysregulation. Among men, both signatures were associated with CRC (odds ratio [OR] = 1.34, 95% confidence interval [CI] = 1.07 to 1.68 per 1-standard deviation increase, inflammation; OR = 1.25, 95% CI = 1.00 to 1.55 metabolic dysregulation); neither signature was associated with CRC in women. A total of 11 metabolites were individually associated with CRC and biomarkers of inflammation or metabolic dysregulation among either men or women. CONCLUSION: We derived metabolomic signatures and identified individual metabolites associated with inflammation, metabolic dysregulation, and CRC, highlighting several metabolites as promising candidates involved in the inflammatory and metabolic dysregulation pathways for CRC incidence.