Associations between common contraceptive use and circulating inflammatory biomarkers.

Ovarian cancer incidence has declined in recent decades, due in part to oral contraceptive (OC) use and tubal ligation. However, intrauterine device (IUD) use has increasingly replaced OC use. As ovarian cancer is an inflammation-related disease, we examined the association of OC use, IUD use, and tubal ligation with plasma levels of C-reactive protein (CRP), interleukin 6 (IL-6), and soluble tumor necrosis factor α receptor 2 (sTNFR2), in the Nurses' Health Study (NHS) and NHSII. After adjusting for reproductive, hormonal, and lifestyle factors, and mutual adjustment for other methods of contraception, there were no differences in inflammatory markers between ever and never use of each method. However, CRP levels decreased from an average 30.4% (-53.6, 4.4) with every 5 years since initial IUD use (P-trend=0.03), while CRP increased an average 9.9% (95% CI: 5.7, 14.3) with every 5 years of use of OC (P-trend<0.0001) as well as differences by BMI and menopausal status. Our results suggest IUD use and tubal ligation are not associated with higher circulating inflammatory markers long term, although long duration of OC use may increase generalized inflammation, which may in part explain why its protective effect wanes over time.

Quantifiable TCR repertoire changes in prediagnostic blood specimens among patients with high-grade ovarian cancer.

High-grade ovarian cancer (HGOC) is a major cause of death in women. Early detection of HGOC usually leads to a cure, yet it remains a clinical challenge with over 90% HGOCs diagnosed at advanced stages. This is mainly because conventional biomarkers are not sensitive enough to detect the microscopic yet metastatic early lesions. In this study, we sequence the blood T cell receptor (TCR) repertoires of 466 patients with ovarian cancer and controls and systematically investigate the immune repertoire signatures in HGOCs. We observe quantifiable changes of selected TCRs in HGOCs that are reproducible in multiple independent cohorts. Importantly, these changes are stronger during stage I. Using pre-diagnostic patient blood samples from the Nurses' Health Study, we confirm that HGOC signals can be detected in the blood TCR repertoire up to 4 years preceding conventional diagnosis. Our findings may provide the basis for future immune-based HGOC early detection criteria.

Impact of insomnia on ovarian cancer risk and survival: a Mendelian randomization study.

BACKGROUND: Insomnia is the most common sleep disorder in patients with epithelial ovarian cancer (EOC). We investigated the causal association between genetically predicted insomnia and EOC risk and survival through a two-sample Mendelian randomization (MR) study. METHODS: Insomnia was proxied using genetic variants identified in a genome-wide association study (GWAS) meta-analysis of UK Biobank and 23andMe. Using genetic associations with EOC risk and overall survival from the Ovarian Cancer Association Consortium (OCAC) GWAS in 66,450 women (over 11,000 cases with clinical follow-up), we performed Iterative Mendelian Randomization and Pleiotropy (IMRP) analysis followed by a set of sensitivity analyses. Genetic associations with survival and response to treatment in ovarian cancer study of The Cancer Genome Atlas (TCGA) were estimated controlling for chemotherapy and clinical factors. FINDINGS: Insomnia was associated with higher risk of endometrioid EOC (OR = 1.60, 95% CI 1.05-2.45) and lower risk of high-grade serous EOC (HGSOC) and clear cell EOC (OR = 0.79 and 0.48, 95% CI 0.63-1.00 and 0.27-0.86, respectively). In survival analysis, insomnia was associated with shorter survival of invasive EOC (OR = 1.45, 95% CI 1.13-1.87) and HGSOC (OR = 1.4, 95% CI 1.04-1.89), which was attenuated after adjustment for body mass index and reproductive age. Insomnia was associated with reduced survival in TCGA HGSOC cases who received standard chemotherapy (OR = 2.48, 95% CI 1.13-5.42), but was attenuated after adjustment for clinical factors. INTERPRETATION: This study supports the impact of insomnia on EOC risk and survival, suggesting treatments targeting insomnia could be pivotal for prevention and improving patient survival. FUNDING: National Institutes of Health, National Cancer Institute. Full funding details are provided in acknowledgments.

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.

Characteristics of Patients With Cancer and COVID-19 Who Discontinued Cancer Treatment.

This cross-sectional study evaluates the prevalence of and characteristics associated with discontinuation of cancer treatment among patients who received a diagnosis of COVID-19 during their treatment planning.

Racial and Ethnic Inequities in Cancer Care Continuity During the COVID-19 Pandemic Among Those With SARS-CoV-2.

Importance: Racially and ethnically minoritized US adults were disproportionately impacted by the COVID-19 pandemic and experience poorer cancer outcomes, including inequities in cancer treatment delivery. Objective: To evaluate racial and ethnic disparities in cancer treatment delays and discontinuations (TDDs) among patients with cancer and SARS-CoV-2 during different waves of the COVID-19 pandemic in the United States. Design, Setting, and Participants: This cross-sectional study used data from the American Society of Clinical Oncology Survey on COVID-19 in Oncology Registry (data collected from April 2020 to September 2022), including patients with cancer also diagnosed with SARS-CoV-2 during their care at 69 US practices. Racial and ethnic differences were examined during 5 different waves of the COVID-19 pandemic in the United States based on case surge (before July 2020, July to November 2020, December 2020 to March 2021, April 2021 to February 2022, and March to September 2022). Exposures: Race and ethnicity. Main Outcomes and Measures: TDD was defined as any cancer treatment postponed more than 2 weeks or cancelled with no plans to reschedule. To evaluate TDD associations with race and ethnicity, adjusted prevalence ratios (aPRs) were estimated using multivariable Poisson regression, accounting for nonindependence of patients within clinics, adjusting for age, sex, body mass index, comorbidities, cancer type, cancer extent, and SARS-CoV-2 severity (severe defined as death, hospitalization, intensive care unit admission, or mechanical ventilation). Results: A total of 4054 patients with cancer and SARS-CoV-2 were included (143 [3.5%] American Indian or Alaska Native, 176 [4.3%] Asian, 517 [12.8%] Black or African American, 469 [11.6%] Hispanic or Latinx, and 2747 [67.8%] White; 2403 [59.3%] female; 1419 [35.1%] aged 50-64 years; 1928 [47.7%] aged ≥65 years). The analysis focused on patients scheduled (at SARS-CoV-2 diagnosis) to receive drug-based therapy (3682 [90.8%]), radiation therapy (382 [9.4%]), surgery (218 [5.4%]), or transplant (30 [0.7%]), of whom 1853 (45.7%) experienced TDD. Throughout the pandemic, differences in racial and ethnic inequities based on case surge with overall TDD decreased over time. In multivariable analyses, non-Hispanic Black (third wave: aPR, 1.56; 95% CI, 1.31-1.85) and Hispanic or Latinx (third wave: aPR, 1.35; 95% CI, 1.13-1.62) patients with cancer were more likely to experience TDD compared with non-Hispanic White patients during the first year of the pandemic. By 2022, non-Hispanic Asian patients (aPR, 1.51; 95% CI, 1.08-2.12) were more likely to experience TDD compared with non-Hispanic White patients, and non-Hispanic American Indian or Alaska Native patients were less likely (aPR, 0.37; 95% CI, 0.16-0.89). Conclusions and Relevance: In this cross-sectional study of patients with cancer and SARS-CoV-2, racial and ethnic inequities existed in TDD throughout the pandemic; however, the disproportionate burden among racially and ethnically minoritized patients with cancer varied across SARS-CoV-2 waves. These inequities may lead to downstream adverse impacts on cancer mortality among minoritized adults in the United States.

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.

Barriers to endocrine therapy adherence: perspectives of Black breast cancer survivors and their providers.

PURPOSE: Adherence to oral endocrine therapy (ET) remains an issue for up to half of women prescribed these medications. There is emerging data that Black breast cancer survivors (BCS) have lower rates of ET adherence. Given the disparities in breast cancer recurrence and survival for Black BCS compared to their White counterparts, the goal of this study is to better understand barriers to ET adherence among Black BCS from the patient and provider perspectives. METHODS: In this qualitative study, we conducted semi-structured interviews between October 29, 2021, and March 1, 2023. Interviews were recorded and transcribed, and coded data were organized into primary and secondary themes. Participants were recruited from a single academic cancer center. A convenience sample of 24 Black BCS and 9 medical oncology providers was included. Eligible BCS were 18 years or older, English-speaking, diagnosed with stage I-III hormone receptor-positive breast cancer, who had initiated ET. RESULTS: Mean age of the BCS was 55 years (interquartile range, IQR 17 years). About one-fourth had a high school diploma or less (26.1%) and 47% completed a college education or higher. Approximately one-third of participants had annual household incomes of $40,000 or less (30.4%) or more than $100,000 (30.4%). Forty-three percent of the patient participants had private insurance; 11% were insured through Medicaid or the federal healthcare exchange; 26.1% had Medicare; and 13% were uninsured. Of the 9 medical oncology providers interviewed, 2 were advanced practice providers, and 7 were medical oncologists. We found 3 major themes: (1) Black BCS often had concerns about ET before initiation; (2) after initiation, both BCS and providers reported side effects as the most impactful barrier to ET adherence; and (3) survivors experienced challenges with managing ET side effects. CONCLUSIONS: Our results suggest that multifaceted support interventions for managing ET-related symptoms may lead to improved adherence to ET among Black women and may reduce disparities in outcomes. IMPLICATIONS FOR CANCER SURVIVORS: Multifaceted support interventions for managing ET-related symptoms may lead to improved adherence to ET among Black breast cancer survivors.

Impact of Pre-Diagnostic Risk Factors on Short- and Long-Term Ovarian Cancer Survival Trajectories: A Longitudinal Observational Study.

Tumor- and treatment-related factors are established predictors of ovarian cancer survival. New studies suggest a differential impact of exposures on ovarian cancer survival trajectories (i.e., rapidly fatal to long-term disease). This study examined the impact of pre-diagnostic risk factors on short- and long-term ovarian cancer survival trajectories in the Canadian context. This population-based longitudinal observational study included women diagnosed with invasive epithelial ovarian cancer from 1995 to 2004 in Ontario. Data were obtained from medical records, interviews, and the provincial cancer registry. Extended Cox proportional hazard models estimated the association between risk factors and all-cause and ovarian cancer-specific mortality by survival time intervals (<3 years (i.e., short-term survival), 3 to <6 years, 6 to <10 years, and ≥10 years (i.e., long-term survival)). Among 1421 women, histology, stage, and residual disease were the most important predictors of all-cause mortality in all survival trajectories, particularly for short-term survival. Reproductive and lifestyle factors did not strongly impact short-term overall survival but were associated with long-term overall survival. As such, among long-term survivors, history of breastfeeding significantly decreased the risk of all-cause mortality (HR 0.65; 95% CI 0.46, 0.93; p < 0.05), whereas smoking history (HR 1.75; 95% CI 1.27, 2.40; p < 0.05) and obesity (HR 1.81; 95% CI 1.24, 2.65; p < 0.05) significantly increased the risk of all-cause mortality. The findings were consistent with ovarian cancer-specific mortality. These findings suggest that pre-diagnostic exposures differentially influence survival time following a diagnosis of ovarian cancer.

Lifetime Exposure to Cigarette Smoke, B-Cell Tumor Immune Infiltration, and Immunoglobulin Abundance in Ovarian Tumors.

BACKGROUND: Cigarette smoke exposure has been linked to systemic immune dysfunction, including for B-cell and immunoglobulin (Ig) production, and poor outcomes in patients with ovarian cancer. No study has evaluated the impact of smoke exposure across the life-course on B-cell infiltration and Ig abundance in ovarian tumors. METHODS: We measured markers of B and plasma cells and Ig isotypes using multiplex immunofluorescence on 395 ovarian cancer tumors in the Nurses' Health Study (NHS)/NHSII. We conducted beta-binomial analyses evaluating odds ratios (OR) and 95% confidence intervals (CI) for positivity of immune markers by cigarette exposure among cases and Cox proportional hazards models to evaluate hazard ratios (HR) and 95% CI for developing tumors with low (

Impact of COVID-19-related experiences on health-related quality of life in cancer survivors in the United States.

OBJECTIVE: Little evidence exists on the impact of the COVID-19 pandemic on cancer survivors, limiting recommendations to improve health-related quality of life (HRQoL) in this population. We describe survivors' pandemic experiences and examine associations between COVID-19-related exposures, psychosocial experiences, and HRQoL. METHODS: Between May 2020-April 2021, survivors completed cross-sectional questionnaires capturing COVID-19-related exposures (e.g., exposure to virus, job loss); psychosocial experiences (i.e., COVID-19-related anxiety/depression, disruptions to health care and daily activities/social interactions, satisfaction with providers' response to COVID, financial hardship, perceived benefits of the pandemic, social support, and perceived stress management ability); and HRQoL. RESULTS: Data were collected from N = 11,325 survivors in the United States. Participants were mostly female (58%), White (89%) and non-Hispanic (88%), and age 63 on average. Breast cancer was the most common diagnosis (23%). Eight percent of participants reported being exposed to COVID-19; 1% tested positive. About 6% of participants lost their jobs, while 24% lost household income. Nearly 30% avoided attending in-person oncology appointments because of the pandemic. Poorer HRQoL was associated with demographic (younger age; female; non-Hispanic White), clinical (Medicare; stage IV disease; hematologic/digestive/respiratory system cancer), and psychosocial factors (low perceived benefits and stress management ability; more disruption to health care and daily activities/social interactions; financial hardship). CONCLUSIONS: COVID-19-related stressors were associated with various psychosocial experiences in cancer survivors, and these psychosocial experiences were associated with HRQoL above and beyond demographic and clinical factors.

Risk factors and health behaviors associated with loneliness among cancer survivors during the COVID-19 pandemic.

Loneliness may exacerbate poor health outcomes particularly among cancer survivors during the COVID-19 pandemic. Little is known about the risk factors of loneliness among cancer survivors. We evaluated the risk factors of loneliness in the context of COVID-19 pandemic-related prevention behaviors and lifestyle/psychosocial factors among cancer survivors. Cancer survivors (n = 1471) seen at Huntsman Cancer Institute completed a survey between August-September 2020 evaluating health behaviors, medical care, and psychosocial factors including loneliness during COVID-19 pandemic. Participants were classified into two groups: 'lonely' (sometimes, usually, or always felt lonely in past month) and 'non-lonely' (never or rarely felt lonely in past month). 33% of cancer survivors reported feeling lonely in the past month. Multivariable logistic regression showed female sex, not living with a spouse/partner, poor health status, COVID-19 pandemic-associated lifestyle factors including increased alcohol consumption and marijuana/CBD oil use, and psychosocial stressors such as disruptions in daily life, less social interaction, and higher perceived stress and financial stress were associated with feeling lonely as compared to being non-lonely (all p < 0.05). A significant proportion of participants reported loneliness, which is a serious health risk among vulnerable populations, particularly cancer survivors. Modifiable risk factors such as unhealthy lifestyle behaviors and psychosocial stress were associated with loneliness. These results highlight the need to screen for unhealthy lifestyle factors and psychosocial stressors to identify cancer survivors at increased risk of loneliness and to develop effective management strategies.

Inequities in the Impacts of Hurricanes and Other Extreme Weather Events for Cancer Survivors.

In this minireview, we examine the impacts of hurricanes and other extreme weather events on cancer survivors, focusing on structural and social determinants of health. We briefly explore influences on biological, psychosocial, and behavioral outcomes and discuss risk and resilience factors in cancer survivorship during and after hurricanes. Our goal is to inform future directions for research that can identify areas in which we can most efficiently improve cancer outcomes and inform changes in health systems, clinical practice, and public health policies. This timely minireview provides researchers and clinicians with an overview of challenges and opportunities for improving disaster preparedness and response for cancer survivors.

Fulfilled Mind, Healthy Gut? Relationships of Eudaimonic Psychological Well-Being With the Gut Microbiome in Postmenopausal Women.

OBJECTIVE: Eudaimonic facets of psychological well-being (PWB), like purpose in life and sense of mastery, are associated with healthy aging. Variation in the gut microbiome may be one pathway by which mental health influences age-related health outcomes. However, associations between eudaimonic PWB and the gut microbiome are understudied. We examined whether purpose in life and sense of mastery, separately, were associated with features of the gut microbiome in older women. METHODS: Participants were from the Mind-Body Study ( N = 206, mean age = 61 years), a substudy of the Nurses' Health Study II cohort. In 2013, participants completed the Life Engagement Test and the Pearlin Mastery Scale. Three months later, up to two pairs of stool samples were collected, 6 months apart. Covariates included sociodemographics, depression, health status, and health behaviors. Analyses examined associations of PWB with gut microbiome taxonomic diversity, overall community structure, and specific species/pathways. To account for multiple testing, statistical significance was established using Benjamini-Hochberg adjusted p values (i.e., q values ≤0.25). RESULTS: We found no evidence of an association between PWB and gut microbiome alpha diversity. In multivariate analysis, higher purpose levels were significantly associated with lower abundance of species previously linked with poorer health outcomes, notably Blautia hydrogenotrophica and Eubacterium ventriosum ( q values ≤0.25). No significant associations were found between PWB and metabolic pathways. CONCLUSIONS: These findings offer early evidence suggesting that eudaimonic PWB is linked with variation in the gut microbiome, and this might be one pathway by which PWB promotes healthy aging.

WITHDRAWN: Impact of spatial clustering of cytotoxic and tumor infiltrating lymphocytes on overall survival in women with high grade serous ovarian cancer.

The authors have withdrawn their manuscript owing to incorrect handling of multiple measures in the survival analyses. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

Breast density analysis of digital breast tomosynthesis.

Mammography shifted to digital breast tomosynthesis (DBT) in the US. An automated percentage of breast density (PD) technique designed for two-dimensional (2D) applications was evaluated with DBT using several breast cancer risk prediction measures: normalized-volumetric; dense volume; applied to the volume slices and averaged (slice-mean); and applied to synthetic 2D images. Volumetric measures were derived theoretically. PD was modeled as a function of compressed breast thickness (CBT). The mean and standard deviation of the pixel values were investigated. A matched case-control (CC) study (n = 426 pairs) was evaluated. Odd ratios (ORs) were estimated with 95% confidence intervals. ORs were significant for PD: identical for volumetric and slice-mean measures [OR = 1.43 (1.18, 1.72)] and [OR = 1.44 (1.18, 1.75)] for synthetic images. A 2nd degree polynomial (concave-down) was used to model PD as a function of CBT: location of the maximum PD value was similar across CCs, occurring at 0.41 × CBT, and PD was significant [OR = 1.47 (1.21, 1.78)]. The means from the volume and synthetic images were also significant [ORs ~ 1.31 (1.09, 1.57)]. An alternative standardized 2D synthetic image was constructed, where each pixel value represents the percentage of breast density above its location. Several measures were significant and an alternative method for constructing a standardized 2D synthetic image was produced.

Quantifiable TCR repertoire changes in pre-diagnostic blood specimens among high-grade ovarian cancer patients.

High grade serous ovarian cancer (HGOC) is a major cause of death in women. Early detection of HGOC usually leads to a cure, yet it remains a clinical challenge with over 90% HGOCs diagnosed at advanced stages. This is mainly because conventional biomarkers are not sensitive to detect the microscopic yet metastatic early HGOC lesions. In this study, we sequenced the blood T cell receptor (TCR) repertoires of 466 ovarian cancer patients and controls, and systematically investigated the immune repertoire signatures in HGOCs. We observed quantifiable changes of selected TCRs in HGOCs that are reproducible in multiple independent cohorts. Importantly, these changes are stronger during stage I. Using pre-diagnostic patient blood samples from the Nurses' Health Study, we confirmed that HGOC signals can be detected in the blood TCR repertoire up to 4 years proceeding conventional diagnosis. Our findings may provide the basis of an immune-based HGOC early detection criterion.

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: We investigated cross-sectional associations between self-reported alcohol intake and serum or plasma concentrations of oestradiol, oestrone, progesterone (in pre-menopausal women only), testosterone, androstenedione, DHEAS (dehydroepiandrosterone sulphate) and SHBG (sex hormone binding globulin) in 45 431 pre-menopausal and 173 476 post-menopausal women. We performed multivariable linear regression separately for UK Biobank, EPIC (European Prospective Investigation into Cancer and Nutrition) and EHBCCG (Endogenous Hormones and Breast Cancer Collaborative Group), and meta-analysed the results. For testosterone and SHBG, we also conducted two-sample Mendelian Randomization (MR) and colocalisation using the ADH1B (Alcohol Dehydrogenase 1B) variant (rs1229984). Results: Alcohol intake was positively, though weakly, associated with all hormones (except progesterone in pre-menopausal women), with increments in concentrations per 10 g/day increment in alcohol intake ranging from 1.7% for luteal oestradiol to 6.6% for post-menopausal DHEAS. There was an inverse association of alcohol with SHBG in post-menopausal women but a small positive association in pre-menopausal women. MR 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%, -4.9%). Colocalisation suggested a shared causal locus at ADH1B between alcohol intake and higher free testosterone and lower SHBG (PP4: 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.