Urinary PGE-M Levels and Risk of Ovarian Cancer

BACKGROUND

Regular aspirin use may lower ovarian cancer risk by blocking the cyclooxygenase enzymes, resulting in lower expression of prostaglandins, including prostaglandin E2 (PGE2). We evaluated whether higher prediagnosis PGE-M (a urinary biomarker of PGE2) was associated with increased ovarian cancer risk in three prospective cohorts.

METHODS

We conducted a case-control study nested in the Nurses' Health Study (NHS), NHSII, and Shanghai Women's Health Study. Our analyses included 304 cases of epithelial ovarian cancer diagnosed from 1996 to 2015 and 600 matched controls. We measured urinary PGE-M using LC/MS with normalization to creatinine. Measures from each study were recalibrated to a common standard. We estimated ORs and 95% confidence intervals (CI) using conditional logistic regression, with PGE-M levels modeled in quartiles. Multivariable models were adjusted for ovarian cancer risk factors.

RESULTS

There was no evidence of an association between urinary PGE-M levels and ovarian cancer risk for women with PGE-M levels in the top versus bottom quartile (OR = 0.80; 95% CI, 0.51-1.27; P _trend = 0.37). We did not observe heterogeneity by histotype (P = 0.53), and there was no evidence of effect modification by body mass index (P _interaction = 0.82), aspirin use (P _interaction = 0.59), or smoking (P _interaction = 0.14).

CONCLUSIONS

Prediagnosis urinary PGE-M levels were not significantly associated with ovarian cancer risk. Larger sample sizes are needed to consider a more modest association and to evaluate associations for specific tumor subtypes.

IMPACT

Systemic prostaglandin levels do not appear strongly associated with ovarian cancer risk. Future research into aspirin use and ovarian cancer risk should consider local prostaglandins and prostaglandin-independent mechanisms.

Abstract 5042: Folate and other B-vitamins and the risk of breast cancer in younger women

Purpose: Prior epidemiologic cohort studies have generally found no associations of folate and other B-vitamins with breast cancer overall, but differences by menopause status have been suggested. However, prior studies have been limited by small numbers to examine the relationship between different plasma measures and related polymorphisms and breast cancer risk among younger women. Therefore, we examined the association of plasma B-vitamins and metabolites, and related genetic variants, with risk of breast cancer among predominantly premenopausal women.

Methods: We conducted a nested case-control study within the Nurses’ Health Study II. From blood samples collected in 1996-1999 and follow-up through 2007, plasma measures were available for 610 cases and 1,207 controls. Unconditional multivariable logistic regression was used to estimate relative risks (RR) of breast cancer and 95% confidence intervals (CIs). We examined whether associations varied by methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase polymorphisms, breast cancer risk factors, or tumor characteristics.

Results: Plasma vitamin B12 was associated with a 71% increase in risk of breast cancer comparing the highest versus lowest quintile (95%CI=1.22-2.39, p-trend=0.02). Plasma folate (comparable RR=1.20, 95%CI=0.85-1.68), pyridoxal 5’-phosphate (RR=1.19, 95%CI=0.85-1.65), cysteine (RR=1.15, 95%CI=0.81-1.63), homocysteine (RR=0.90, 95%CI=0.65-1.25), and cysteinylglycine (RR=0.92, 95%CI=0.65-1.31) were not associated with overall breast cancer risk. Folate was significantly positively associated with invasive (RR highest tertile vs. lowest=1.48, 95%CI=1.09-2.01) and estrogen receptor-positive/progesterone receptor-positive breast cancer (RR T3 vs. T1= 1.59, 95%CI= 1.12-2.27) and the invasive association was suggestively stronger for bloods collected post-fortification (p-heterogeneity=0.19). Several nutrient/breast cancer associations varied across subgroups defined by age, smoking, alcohol, multivitamin use and MTHFR status (p-interaction<0.05).

Conclusions: Overall, plasma B-vitamins and metabolites were not consistently associated with lower breast cancer risk. For increasing plasma folate and B12 levels higher risk of invasive breast cancer was observed. Additionally, there may be associations in subgroups defined by related genetic variants, breast cancer risk factors, and tumor factors. Future studies in younger women are needed to confirm findings.

Citation Format: Serena C. Houghton, A Heather Eliassen, Shumin Zhang, Jacob Selhub, Bernard A. Rosner, Walter C. Willett, Susan E. Hankinson. Folate and other B-vitamins and the risk of breast cancer in younger women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5042.

Elucidating Under-Studied Aspects of the Link Between Obesity and Multiple Myeloma: Weight Pattern, Body Shape Trajectory, and Body Fat Distribution

Background

Although obesity is an established modifiable risk factor for multiple myeloma (MM), several nuanced aspects of its relation to MM remain unelucidated, limiting public health and prevention messages.

Methods

We analyzed prospective data from the Nurses' Health Study and Health Professionals Follow-Up Study to examine MM risk associated with 20-year weight patterns in adulthood, body shape trajectory from ages 5 to 60 years, and body fat distribution. For each aforementioned risk factor, we report hazard ratios (HRs) and 95% confidence intervals (CIs) for incident MM from multivariable Cox proportional-hazards models.

Results

We documented 582 incident MM cases during 4 280 712 person-years of follow-up. Persons who exhibited extreme weight cycling, for example, those with net weight gain and one or more episodes of intentional loss of at least 20 pounds or whose cumulative intentional weight loss exceeded net weight loss with at least one episode of intentional loss of 20 pounds or more had an increased MM risk compared with individuals who maintained their weight (HR = 1.71, 95% CI = 1.05 to 2.80); the association was statistically nonsignificant after adjustment for body mass index. We identified four body shape trajectories: lean-stable, lean-increase, medium-stable, and medium-increase. MM risk was higher in the medium-increase group than in the lean-stable group (HR = 1.62, 95% CI = 1.22 to 2.14). Additionally, MM risk increased with increasing hip circumference (HR per 1-inch increase: 1.03, 95% CI = 1.01 to 1.06) but was not associated with other body fat distribution measures.

Conclusions

Maintaining a lean and stable weight throughout life may provide the strongest benefit in terms of MM prevention.

The relation of telomere length at midlife to subsequent 20-year depression trajectories among women

BACKGROUND

Telomeres cap and protect DNA but shorten with each somatic cell division. Aging and environmental and lifestyle factors contribute to the speed of telomere attrition. Current evidence suggests a link between relative telomere length (RTL) and depression but the directionality of the relationship remains unclear. We prospectively examined associations between RTL and subsequent depressive symptom trajectories.

METHODS

Among 8,801 women of the Nurses' Health Study, depressive symptoms were measured every 4 years from 1992 to 2012; group-based trajectories of symptoms were identified using latent class growth-curve analysis. Multinomial logistic models were used to relate midlife RTLs to the probabilities of assignment to subsequent depressive symptom trajectory groups.

RESULTS

We identified four depressive symptom trajectory groups: minimal depressive symptoms (62%), worsening depressive symptoms (14%), improving depressive symptoms (19%), and persistent-severe depressive symptoms (5%). Longer midlife RTLs were related to significantly lower odds of being in the worsening symptoms trajectory versus minimal trajectory but not to other trajectories. In comparison with being in the minimal symptoms group, the multivariable-adjusted odds ratio of being in the worsening depressive symptoms group was 0.78 (95% confidence interval, 0.62-0.97; p = 0.02), for every standard deviation increase in baseline RTL.

CONCLUSIONS

In this large prospective study of generally healthy women, longer telomeres at midlife were associated with significantly lower risk of a subsequent trajectory of worsening mood symptoms over 20 years. The results raise the possibility of telomere shortening as a novel contributing factor to late-life depression.

Predicting Circulating CA125 Levels among Healthy Premenopausal Women

BACKGROUND

Cancer antigen 125 (CA125) is the most promising ovarian cancer screening biomarker to date. Multiple studies reported CA125 levels vary by personal characteristics, which could inform personalized CA125 thresholds. However, this has not been well described in premenopausal women.

METHODS

We evaluated predictors of CA125 levels among 815 premenopausal women from the New England Case Control Study (NEC). We developed linear and dichotomous (≥35 U/mL) CA125 prediction models and externally validated an abridged model restricting to available predictors among 473 premenopausal women in the European Prospective Investigation into Cancer and Nutrition Study (EPIC).

RESULTS

The final linear CA125 prediction model included age, race, tubal ligation, endometriosis, menstrual phase at blood draw, and fibroids, which explained 7% of the total variance of CA125. The correlation between observed and predicted CA125 levels based on the abridged model (including age, race, and menstrual phase at blood draw) had similar correlation coefficients in NEC (r = 0.22) and in EPIC (r = 0.22). The dichotomous CA125 prediction model included age, tubal ligation, endometriosis, prior personal cancer diagnosis, family history of ovarian cancer, number of miscarriages, menstrual phase at blood draw, and smoking status with AUC of 0.83. The abridged dichotomous model (including age, number of miscarriages, menstrual phase at blood draw, and smoking status) showed similar AUCs in NEC (0.73) and in EPIC (0.78).

CONCLUSIONS

We identified a combination of factors associated with CA125 levels in premenopausal women.

IMPACT

Our model could be valuable in identifying healthy women likely to have elevated CA125 and consequently improve its specificity for ovarian cancer screening.

Physical activity is not related to risk of early menopause in a large prospective study

STUDY QUESTION

Is physical activity associated with incident early menopause?

SUMMARY ANSWER

Physical activity is not associated with incident early menopause.

WHAT IS KNOWN ALREADY

Lifestyle factors such as physical activity may influence menopause timing, but results from prior research are inconsistent.

STUDY DESIGN, SIZE, DURATION

We evaluated the association between physical activity and the occurrence of early natural menopause in a prospective cohort study, the Nurses' Health Study II. Women were followed prospectively from 1989 to 2011.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Our analysis included 107 275 women who were premenopausal at baseline. Menopause status was self-reported biennially. Time per week participating in specific activities was reported approximately every 4 years and used to calculate metabolic task hours per week (MET h/week). We used Cox proportional hazards model to evaluate the association between physical activity and incidence of natural menopause before age 45 years while controlling for potential confounding factors.

MAIN RESULTS AND THE ROLE OF CHANCE

There were 2 786 study members who experienced menopause before the age of 45. After adjustment for age, smoking and other factors, we observed no association between adulthood physical activity and early menopause. For example, compared to women reporting <3 MET h/week, the hazard ratio for women in the highest category (≥42 MET h/week) of cumulatively-averaged total physical activity was 0.89 (95% confidence interval: 0.76-1.04; P-trend: 0.26). Neither moderate nor strenuous activity in adolescence and young adulthood were related to risk. The relation of physical activity and early menopause did not vary across strata of body mass index or smoking status.

LIMITATIONS, REASONS FOR CAUTION

Physical activity and menopausal status were self-reported, but repeated assessment of physical activity and prospective report of menopause status likely reduce the potential for non-differential misclassification. While the majority of our study participants were white, it is unlikely that the physiological relation of activity and early menopause varies by ethnicity.

WIDER IMPLICATIONS OF THE FINDINGS

Findings from our large prospective study do not support an important association between physical activity and early menopause.

STUDY FUNDING/COMPETING INTEREST(S)

This project was supported by UM1CA176726 and R01HD078517 from the National Institutes of Health, Department of Health and Human Services. No competing interests are declared.

TRIAL REGISTRATION NUMBER

N/A.

Dietary Pattern and Risk of Multiple Myeloma in Two Large Prospective US Cohort Studies

Background

The limited data on specific dietary components and risk of multiple myeloma (MM) show no consistent association. Studies have not examined the association of dietary pattern with MM risk.

Methods

In prospective cohorts of 69 751 women (Nurses’ Health Study, 1984–2014) and 47 232 men (Health Professionals Follow-up Study, 1986–2014), we examined the association between dietary pattern and risk of MM using Cox proportional hazard models. Diet was assessed repeatedly every 4 years with food frequency questionnaires and was used to calculate dietary patterns including the Alternate Healthy Eating Index-2010, Alternate Mediterranean Diet, Dietary Approaches to Stop Hypertension, Prudent and Western patterns, the empirical dietary inflammatory pattern (EDIP), and empirical dietary indices for insulin resistance (EDIR) and hyperinsulinemia (EDIH).

Results

During 2 792 257 person-years of follow-up, we identified 478 incident MM cases (215 women, 263 men). In men, high EDIP was statistically significantly associated with a 16% increase in MM risk (hazard ratio [HR] = 1.16, 95% confidence interval [CI] = 1.02 to 1.32 per 1-SD increase). Moreover, EDIR and EDIH had a suggestive positive association (EDIR: HR = 1.09, 95% CI = 0.96 to 1.24; and EDIH: HR = 1.11, 95% CI = 0.97 to 1.28 per 1-SD increase). We observed no other associations with MM risk in men and no associations for any dietary pattern with MM risk in women.

Conclusions

We present the first evidence for a role of diets with higher inflammatory or insulinemic potential in MM development. Further studies are warranted to explore these associations in other populations, including the apparent restriction to men.

Association Between Changes in Postpartum Weight and Waist Circumference and Changes in Cardiometabolic Risk Factors Among Women With Recent Gestational Diabetes

INTRODUCTION

Women with gestational diabetes mellitus (GDM) have a 30% to 70% risk for developing type 2 diabetes and are at increased risk for cardiovascular disease. Little is known about how anthropometric changes in the first postpartum year modify cardiometabolic risk factors.

METHODS

We randomly assigned women in the Balance After Baby study to an intervention group consisting of participation in a web-based lifestyle program or to a control group in which no program was offered. We measured weight, height, waist circumference, blood pressure, lipids, insulin, adiponectin, interleukin-6, and high-sensitivity C-reactive protein, and we conducted 2-hour oral glucose tolerance tests at 6 weeks, 6 months, and 12 months postpartum. We evaluated whether women assigned to the intervention had improved cardiometabolic risk markers compared with the control group. We then conducted a post-hoc analysis, pooling the 2 groups to compare changes in weight and waist circumference with changes in cardiometabolic risk factors.

RESULTS

Women in the intervention group did not significantly improve cardiometabolic risk markers compared with women in the control group. We noted a large overlap of weight change and change in waist circumference between groups. In our post-hoc analysis pooling groups, changes in diabetes and cardiovascular risk factors were significantly correlated with changes in weight and waist circumference. The strongest associations were observed for fasting insulin, HOMA, and fasting glucose.

CONCLUSION

Anthropometric changes in weight and waist circumference in women with recent GDM may affect cardiometabolic risk factors, even in the first postpartum year. Our study demonstrates the importance of the postpartum year as an opportunity to decrease future risk for diabetes and cardiovascular disease in women with a history of GDM.

Plasma B-vitamins and one-carbon metabolites and the risk of breast cancer in younger women

PURPOSE

We examined the association of plasma B-vitamins and metabolites, and related genetic variants, with risk of breast cancer among predominantly premenopausal women.

METHODS

We conducted a nested case-control study within the Nurses' Health Study II. From blood samples collected in 1996-1999 and follow-up through 2007, plasma measures were available for 610 cases and 1207 controls. Unconditional multivariable logistic regression was used to estimate relative risks (RR) of breast cancer and 95% confidence intervals (CIs). We examined whether associations varied by methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase polymorphisms, breast cancer risk factors, or tumor characteristics.

RESULTS

Plasma vitamin B₁₂ was associated with a 64% higher risk of breast cancer comparing the highest versus lowest quintile (95% CI 1.17-2.29, p-trend = 0.02). Plasma folate (comparable RR = 1.18, 95% CI 0.84-1.66), pyridoxal 5'-phosphate (RR = 1.18, 95% CI 0.85-1.64), homocysteine (RR = 0.93, 95% CI 0.67-1.28), cysteine (RR = 1.14, 95% CI 0.81-1.62), and cysteinylglycine (RR = 0.93, 95% CI 0.66-1.31) were not associated with overall breast cancer risk. Folate was significantly positively associated with invasive and estrogen receptor-positive/progesterone receptor-positive breast cancer, and this association was suggestively stronger for bloods collected post-fortification. Several nutrient/breast cancer associations varied across subgroups defined by age, smoking, alcohol, multivitamin use, and MTHFR status (p-interaction < 0.05).

CONCLUSIONS

Overall, plasma B-vitamins and metabolites were not associated with lower breast cancer risk. Plasma vitamin B-12 was positively associated with higher risk of overall breast cancer, and plasma folate was positively associated with risk of invasive breast cancer. Additionally, there may be associations in subgroups defined by related genetic variants, breast cancer risk factors, and tumor factors. Further studies in younger women and in the post-fortification era are needed to confirm these findings.

Fruit and vegetable consumption and breast cancer incidence: Repeated measures over 30 years of follow-up

We evaluated the relation of fruit and vegetable consumption, including specific fruits and vegetables, with incident breast cancer characterized by menopausal status, hormone receptor status and molecular subtypes. Fruit and vegetable consumption, cumulatively averaged across repeated, validated questionnaires, was examined in relation to risk of invasive breast cancer among 182,145 women initially aged 27-59 years in the Nurses' Health Study (NHS, 1980-2012) and NHSII (1991-2013). Cox proportional hazards regression, adjusted for known risk factors, was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) and assessed tumors by hormone receptor status and molecular subtypes. We prospectively documented 10,911 invasive breast cancer cases. Greater intake of total fruits and vegetables, especially cruciferous and yellow/orange vegetables, was associated with significantly lower breast cancer risk (>5.5 vs. ≤2.5 servings/day HR = 0.89, 95% CI = 0.83-0.96; ptrend = 0.006). Intake of total vegetables was especially associated with lower risk of estrogen receptor negative tumors (HR per 2 additional servings/day as a continuous variable = 0.84, 95%CI = 0.77-0.93; pheterogeneity = 0.02). Among molecular subtypes, higher intake of total fruits and vegetables (HR per 2 additional servings/day as a continuous variable) was most strongly associated with lower risk of human epidermal growth factor receptor 2 (HER2)-enriched (HR = 0.79, 95%CI = 0.67-0.93), basal-like (HR = 0.84, 95%CI = 0.72-0.97) and luminal A (HR = 0.94, 95%CI = 0.89-0.99), but not with luminal B tumors (pheterogeneity = 0.03). In conclusion, our findings support that higher intake of fruits and vegetables, and specifically cruciferous and yellow/orange vegetables, may reduce the risk of breast cancer, especially those that are more likely to be aggressive tumors.

Sex Differences in Coronary Microvascular Function in Individuals With Type 2 Diabetes

Cardiovascular (CV) disease fatality rates are higher for women compared with men with diabetes despite lower rates of obstructive coronary artery disease (CAD). Impaired coronary flow reserve (CFR), the ratio of adenosine-stimulated to rest myocardial blood flow (MBF), is an indicator of coronary microvascular dysfunction and predicts major adverse CV events. We performed a post hoc analysis to determine whether there was a sex disparity in coronary microvascular dysfunction among 46 men and 27 women with well-controlled type 2 diabetes and without clinical evidence of obstructive CAD. We found that women had a higher rest MBF, lower CFR, and worse diastolic function compared with men. In addition, rest MBF was positively correlated with worse diastolic function in women. We previously showed that mineralocorticoid blockade improved CFR in men and women with type 2 diabetes, implicating aldosterone in the pathophysiology of coronary microvascular dysfunction. We therefore examined aldosterone levels and found that women had larger increases in aldosterone in response to an angiotensin-II infusion than did men. In conclusion, among individuals with type 2 diabetes and good cardiometabolic control, women had worse myocardial perfusion and diastolic function compared with men. The greater aldosterone responsivity in women may be a mechanism for this sex effect.

A Prospective Analysis of Red Blood Cell Trans Fatty Acid Levels and Risk of Non-Hodgkin Lymphoma

To confirm previous reports of increased non-Hodgkin lymphoma (NHL) risk with higher intake of dietary trans fatty acids (TFA), we conducted the first prospective study of pre-diagnosis red blood cell (RBC) TFA levels and risk of NHL and common NHL histologic subtypes (diffuse large-B cell lymphoma (DLBCL), follicular lymphoma, chronic lymphocytic lymphoma/small lymphocytic leukemia, other B-cell NHL, T-cell NHL). Methods: We conducted a nested case-control study in Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS) participants with archived RBC specimens and no history of cancer at sample collection (NHS: 1989–90; HPFS: 1994–5). We confirmed 583 NHL cases (332 women in NHS, 251 men in HPFS) and matched 583 controls by cohort (sex), age, race/ethnicity and blood draw date/time. We analyzed RBC TFAs using gas-liquid chromatography; individual TFA levels were expressed as a percentage of total fatty acids. We used unconditional logistic regression, adjusted for the matching factors, to estimate odds ratios (OR) and 95% confidence intervals (CI) for overall NHL risk per 1 standard deviation (SD) unit increase in TFA level. We fitted multivariate polytomous logistic regression models to assess associations for the specific subtypes listed above. Results: Total and individual RBC TFAs were not associated with overall NHL risk or risk of most histologic subtypes. However, we observed a positive association of total RBC TFA with DLBCL risk (n = 86 cases; OR [95% CI] per 1 SD: 1.29 [1.02, 1.64]), driven primarily by 18:1 TFAs (1.35 [1.07, 1.72]). Among 18:1 TFA isomers, we found a positive association for trans 18:1 n-9 (elaidic acid; 1.33 [1.05, 1.68]) but not for other isomers. Conclusions: We observed significant positive associations for RBC TFA levels with DLBCL risk. These findings are consistent with published studies of self-reported TFA intake; further, previous studies have shown that TFA levels – particularly trans 18:1n-9, which is industrially-derived – are positively correlated with biomarkers of inflammation and immune activation, supporting the biologic plausibility of our findings. Food industry and public health measures to diminish TFA intake may help to reduce risk of NHL, and particularly of DLBCL.

Anti-Müllerian hormone levels and incidence of early natural menopause in a prospective study

STUDY QUESTION

Are anti-Müllerian hormone (AMH) levels assessed in women aged 32-44 associated with risk of incident early natural menopause?

SUMMARY ANSWER

We observed strong, significant associations between lower AMH levels and higher risk of early menopause.

WHAT IS KNOWN ALREADY

The ability to predict risk early menopause, defined as menopause before age 45, prior to fertility decline would improve options for family planning and cardiovascular disease prevention. Though AMH is an established marker of menopause timing in older reproductive-aged women, whether AMH is associated with risk of early menopause has not been evaluated.

STUDY DESIGN, SIZE, DURATION

We assessed these relations in a nested case-control study within the prospective Nurses' Health Study II cohort. Premenopausal blood samples were collected in 1996-1999. Participants were followed until 2011 for early natural menopause, with follow-up rates >94%.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Early menopause cases (n = 327) were women reporting natural menopause between blood collection and age 45. Controls (n = 491) experienced menopause after age 45 and included 327 cases matched to controls on the basis of age at blood draw (±4 months) and other factors. AMH levels up to 12 years before early menopause were assayed in 2016.

MAIN RESULTS AND THE ROLE OF CHANCE

In multivariable conditional logistic regression models adjusting for matching factors, body mass index, smoking, parity, oral contraceptive use, and other factors, each 0.10 ng/ml decrease in AMH was associated with a 14% higher risk of early menopause (95% confidence interval (CI) 1.10 to 1.18; P < 0.001). In polynomial regression models including linear and quadratic terms for AMH, odds ratios for early menopause for women with AMH levels of 1.5, 1.0 and 0.5 ng/ml compared to 2.0 ng/ml were 2.6, 7.5 and 23 (all P < 0.001). Significant associations were observed irrespective of smoking status, adiposity, infertility history and menstrual cycle characteristics. Furthermore, models assessing the predictive ability of AMH showed high concordance, and C-statistics were high, ranging from 0.68 (age ≤35) to 0.93 (age 42).

LIMITATIONS, REASONS FOR CAUTION

Our population was relatively homogenous with respect to race/ethnicity. Further work in more ethnically diverse populations is needed.

WIDE IMPLICATION OF THE FINDINGS

To our knowledge, this is the first prospective study to evaluate whether AMH levels are associated with early menopause. These findings support the utility of AMH as a clinical marker of early menopause in otherwise healthy women.

STUDY FUNDING/COMPETING INTEREST(S)

This project was supported by UM1CA176726, R01CA67262, and R01HD078517 from the U.S. Department of Health and Human Services, National Institutes of Health. No competing interests declared.

Associations of early life and adulthood adiposity with risk of epithelial ovarian cancer

BACKGROUND

Few studies have evaluated the association between early life adiposity and ovarian cancer risk. Adiposity during different periods of life may be differentially associated with the risk.

PATIENTS AND METHODS

We prospectively followed 133 526 women in the Nurses' Health Study (NHS; 1980-2012) and NHSII (1989-2013). Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident ovarian cancer (N = 788) according to validated measures for early life adiposity [body mass index (BMI) at age 10 imputed from somatotype and recalled BMI at age 18) as well as BMI change between age 10 and 18 and after age 18 (current weight assessed on every biennial questionnaire since baseline).

RESULTS

After mutual adjustment for BMI at age 10, BMI at age 18 and current BMI, the HR (95% CI) for ovarian cancer risk per 5 kg/m2 was 0.84 (0.74-0.96) for BMI at age 10 (P-trend = 0.01), 1.17 (1.03-1.33) for BMI at age 18 (P-trend = 0.02), and 1.06 (0.99-1.14) for current BMI (P-trend = 0.08). However, the inverse association with BMI at age 10 was attenuated after adjusting for BMI change between age 10 and 18 and BMI change after age 18 (HR per 5 kg/m2: 1.04; 95% CI 0.91-1.20; P-trend = 0.55). By contrast, BMI change between age 10 and 18 was strongly positively associated with ovarian cancer risk (HR per 5 kg/m2 increase: 1.24; 95% CI 1.11-1.39; P-trend = 0.0002), whereas BMI change since age 18 was only slightly associated with risk (HR per 5 kg/m2 increase: 1.06; 95% CI 0.99-1.14; P-trend = 0.10). These associations were in general stronger for premenopausal cases or non-serous tumors.

CONCLUSION

Early life changes in adiposity were more strongly associated with ovarian cancer risk than adulthood changes. The specific mechanisms underlying the associations with adiposity changes during early life warrant further investigation.

Plasma B-vitamin and one-carbon metabolites and risk of breast cancer before and after folic acid fortification in the United States

Prior epidemiologic findings for plasma folate and B-vitamins and breast cancer risk are inconsistent and have not assessed the influence of folic acid fortification. Therefore, we examined the associations of plasma folate, B₁₂ , pyridoxal 5'-phosphate (PLP), homocysteine, cysteine and cysteinylglycine with breast cancer risk, before and after fortification. We conducted a nested case-control study within the prospective Nurses' Health Study. In 1989-1990 (pre-fortification), 32,826 women donated a blood sample and 18,743 donated an additional blood sample in 2000-2001 (post-fortification). Between the first blood collection and 2006, 1874 incident breast cancer cases with at least one blood sample and 367 with two were 1:1 matched to controls. Conditional logistic regression was used to estimate relative risks (RR) and 95% confidence intervals (CI) adjusting for breast cancer risk factors. Overall, higher plasma folate, B₁₂ , PLP, homocysteine, cysteine and cysteinylglycine levels were not associated with breast cancer risk. Associations did not vary by in situ/invasive, hormone receptor status, or tumor molecular subtype. Additionally, associations were null before and after fortification. For example, the RR (95% CI) for the highest versus lowest tertile of 1990 (pre-fortification) plasma folate with 1990-2000 follow-up was 0.93 (0.75-1.16) and for the 2000 plasma folate (post-fortification) with 2000-2006 follow-up the RR (95% CI) was 1.17 (0.79-1.74). Plasma folate, B₁₂ , PLP, homocysteine, cysteine and cysteinylglycine were not significantly associated with breast cancer overall, before and after fortification, or with specific tumor molecular subtypes. However, long term associations (>8 years) after the implementation of fortification could not be examined.

A Prospective Study of Dairy-Food Intake and Early Menopause

Early natural menopause, the cessation of ovarian function prior to age 45 years, affects approximately 10% of women and increases risk of cardiovascular disease and other adverse conditions. Laboratory evidence suggests a potential role of dairy foods in the ovarian aging process; however, no prior epidemiologic studies have evaluated how dairy-food intake is associated with risk of early menopause. We therefore evaluated how intakes of total, low-fat, high-fat, and individual dairy foods were associated with early menopause in Nurses' Health Study II. Women who were premenopausal at the start of follow-up in 1991 were followed until 2011 for early menopause. Food frequency questionnaires were used to assess dietary intake. In Cox proportional hazards models adjusting for age, smoking, and other factors, total baseline dairy-food intake of ≥4 servings/day versus <4 servings/week was associated with 23% lower risk of early menopause (hazard ratio = 0.77, 95% confidence interval: 0.64, 0.93; P for trend = 0.08). Associations appeared to be limited to low-fat dairy foods (for ≥2 servings/day vs. <3 servings/month, hazard ratio = 0.83, 95% confidence interval: 0.68, 1.01; P for trend = 0.02), whereas high-fat dairy-food intake was not associated with early menopause. Low-fat dairy foods may represent a modifiable risk factor for reducing risk of early menopause among premenopausal women.

Comparison of Performance Between a Short Categorized Lifestyle Exposure-based Colon Cancer Risk Prediction Tool and a Model Using Continuous Measures

Risk prediction models that estimate an individual's risk of developing colon cancer could be used for a variety of clinical and public health interventions, including offering high-risk individuals enhanced screening or lifestyle interventions. However, if risk prediction models are to be translated into actual clinical and public health practice, they must not only be valid and reliable, but also be easy to use. One way of accomplishing this might be to simplify the information that users of risk prediction tools have to enter, but it is critical to ensure no resulting detrimental effects on model performance. We compared the performance of a simplified, largely categorized exposure-based colon cancer risk model against a more complex, largely continuous exposure-based risk model using two prospective cohorts. Using data from the Nurses' Health Study and the Health Professionals Follow-up Study we included 816 incident colon cancer cases in women and 412 in men. The discrimination of models was not significantly different comparing a categorized risk prediction model with a continuous prediction model in women (c-statistic 0.600 vs. 0.609, P _diff = 0.07) and men (c-statistic 0.622 vs. 0.618, P _diff = 0.60). Both models had good calibration in men [observed case count/expected case count (O/E) = 1.05, P > 0.05] but not in women (O/E = 1.19, P < 0.01). Risk reclassification was slightly improved using categorized predictors in men [net reclassification index (NRI) = 0.041] and slightly worsened in women (NRI = -0.065). Categorical assessment of predictor variables may facilitate use of risk assessment tools in the general population without significant loss of performance.

Anti-Inflammatory Drug Use and Ovarian Cancer Risk by COX1/COX2 Expression and Infiltration of Tumor-Associated Macrophages

BACKGROUND

Nonsteroidal anti-inflammatory drug (NSAID) use may affect ovarian cancer risk via prostaglandin synthesis and tumor-associated macrophage (TAM) infiltration. We evaluated if associations between aspirin or non-aspirin NSAID use and ovarian cancer risk differed by tumor expression of prostaglandin-related (COX1, COX2) and TAM-related (CD68, CD163) markers.

METHODS

We evaluated cases and matched controls from the Nurses' Health Study (NHS), NHSII, and New England Case-Control Study (NECC). Cases with IHC data on COX1 and COX2 (n = 532) or CD68 and CD163 (n = 530) were included. We used polytomous logistic regression, adjusted for ovarian cancer risk factors, to estimate OR for NSAID use and ovarian cancer risk by marker level.

RESULTS

Recent aspirin use had a nonsignificant inverse association and recent non-aspirin NSAID use had no association with ovarian cancer risk. NSAID use was not differentially associated with ovarian cancer by COX1 or COX2 expression. However, recent aspirin use was associated with lower ovarian cancer risk for high [OR 0.54; 95% confidence interval (CI), 0.37-0.78], but not low (OR 1.50; 95% CI, 0.97-2.31), CD163 density (P _{heterogeneity} < 0.001). Similar results were observed for aspirin duration and tablets and for recent non-aspirin NSAID use. Results were not clearly different by macrophage density defined by the less specific macrophage marker, CD68.

CONCLUSIONS

NSAID use was inversely associated with risk of ovarian cancer with high density CD163, a marker for M2-type, immunosuppressive macrophages. However, the relationship did not differ by prostaglandin synthesis markers.

IMPACT

Future research should explore prostaglandin-independent mechanisms for the association between NSAID use and ovarian cancer risk, including immune mechanisms.

Adult adiposity and risk of early menopause

STUDY QUESTION

Is adult adiposity associated with early menopause?

SUMMARY ANSWER

Overall and abdominal adiposity were non-linearly associated with odds for early natural menopause with elevated odds observed among women who were underweight in early or mid-adulthood compared to lean-normal weight women.

WHAT IS KNOWN ALREADY

High and low adiposity have been associated with reproductive function and may potentially impact timing of menopause. It is unclear whether various aspects of adiposity are associated with risk of early menopause.

STUDY DESIGN, SIZE, DURATION

Prospective cohort study that examined data from 78 759 premenopausal women from the Nurses' Health Study II who were followed from 1989 to 2011 for incidence of early natural menopause.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were aged 25-42 years and premenopausal at baseline in 1989, when information on menopausal status, height and weight was reported via questionnaire. Information on menopausal status, type of menopause (natural, surgical, radiation/chemotherapy), hormone therapy use and weight was updated every two years along with information on smoking, physical activity and other behavioral and health-related factors. Multivariable logistic regression was used to estimate odds ratios for early menopause, defined as natural menopause before age 45 years, by aspects of adiposity.

MAIN RESULTS AND THE ROLE OF CHANCE

Early natural menopause was reported by 2804 participants. Body mass index (BMI) was non-linearly associated with risk for early menopause. Compared to women with BMI = 18.5-22.4 kg/m2, those with BMI < 18.5 kg/m2 had a significant 30% higher odds of early menopause (95% confidence interval (CI) = 1.08, 1.57), while women with BMIs between 25.0-29.9 kg/m2 had significant 21-30% lower odds. Odds were not higher in women with BMI ≥ 35.0 kg/m2 in fully adjusted analysis. Non-linear associations with higher odds in underweight women were also observed for age 18 and age 35 BMI, though lower odds for overweight women was only observed for age 35 BMI. Odds were highest among women with age 18 BMI < 18.5 kg/m2 reporting severe weight cycling.

LIMITATIONS, REASONS FOR CAUTION

Though weight and early menopause status were self-reported, validation studies conducted among Nurses' Health Study participants suggest that self-reported weight is highly correlated with directly measured weight, and prospective self-reported menopausal status is highly reproducible. It is possible that underweight women may have been misclassified with an earlier age at menopause if being underweight led to amenorrhea.

WIDER IMPLICATIONS OF THE FINDINGS

In one of the few studies to prospectively examine a variety of adiposity measures and risk for early menopause, our findings that women who were underweight in early or mid-adulthood had elevated risk for early menopause can assist in efforts to better understand the etiology of early menopause. Additional prospective research is needed to understand how low adiposity may physiologically impact timing of menopause.

STUDY FUNDING/COMPETING INTEREST(S)

This study was conducted with funding from NIH UM1CA176726 and R01HD078517. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

Not applicable.

Menstrual Cycle Characteristics in Adolescence and Early Adulthood Are Associated With Risk of Early Natural Menopause

CONTEXT

Early natural menopause (i.e., before age 45 years) is associated with increased risk of adverse outcomes. Associations of earlier menopause with younger age at menarche and short and/or regular cycle length are suggested, but study findings are inconsistent and few address early menopause risk.

OBJECTIVE

To evaluate the relationship between menstrual cycle characteristics in early life with incident early natural menopause.

DESIGN

The prospective Nurses' Health Study 2 (1989 to 2011).

SETTING AND PARTICIPANTS

Women ages 25 to 42 years and premenopausal in 1989 (N = 108,811).

MAIN OUTCOME MEASURE(S)

Risk of early natural menopause not due to surgery, radiation, or chemotherapy (n = 2794) was evaluated with Cox proportional hazards models. Anti-Müllerian hormone (AMH) levels were considered in a nested case-control sample (n = 820).

RESULTS

In adjusted models, risk was associated with earlier age at menarche (P for trend = 0.05), shorter (P for trend < 0.0001), and more-regular cycles (P for < 0.0001). The hazard ratio (HR) for women with age at menarche ≤9 (vs. 12) years was 1.28 (95% CI, 0.99 to 1.67). Women reporting usual menstrual cycle lengths <25 days at ages 18 to 22 years had substantially higher risk of early menopause (HR, 1.70; 95% CI, 1.47 to 1.96) than women with 26- to 31-day cycles, whereas women with ≥40 day cycles had lower risk (HR, 0.44; 95% CI, 0.34 to 0.58). Women with irregular cycle length had lower risk compared with women with regular cycles (HR, 0.51; 95% CI, 0.43 to 0.60). Associations with AMH concentrations among the nested case-control subset were consistent with these findings.

CONCLUSION

Results from this large prospective study of early menopause suggest an influence of accelerated oocyte depletion on risk and may help clarify the etiology of early menopause.

Androgen receptor expression in normal breast tissue and subsequent breast cancer risk

Sex steroid hormone signaling is critical in the development of breast cancers, although the role of the androgen receptor remains unclear. This study evaluated androgen receptor (AR) expression in normal breast tissue as a potential marker of breast cancer risk. We conducted a nested case-control study of women with benign breast disease (BBD) within the Nurses' Health Studies. Epithelial AR expression was assessed by immunohistochemistry in normal tissue from the BBD biopsy and the percent of positive nuclei was estimated in ordinal categories of 10% for 78 breast cancer cases and 276 controls. Logistic regression models adjusting for the matching factors and BBD lesion type were used to calculate odds ratios (ORs) for the association between AR expression (tertiles: ≤10%, 11-30%, and >30%) and breast cancer risk. AR expression in normal breast tissue was not associated with subsequent breast cancer risk (OR_T3vsT1 = 0.9, 95% CI = 0.4-1.8, p trend = 0.68). In comparison with low AR/low ER women, ORs of 0.4 (95% CI = 0.1-1.2) for high AR/high ER women, 1.8 (95% CI = 0.4-7.8) for low AR/high ER women, and 0.7 (95% CI = 0.3-1.6) for high AR/low ER women were observed (p interaction = 0.21). Ki67 did not modify the association between AR expression and breast cancer risk (p interaction = 0.75). There was little evidence for an overall association between AR expression in normal breast tissue and breast cancer risk. These findings did not show that the AR association varied by Ki67 expression in normal breast tissue, though there was suggestive heterogeneity by ER expression.

Vitamin D Status Is Not Associated with Risk of Early Menopause

Background

Early natural menopause, the cessation of ovarian function before age 45 y, is positively associated with cardiovascular disease and other conditions. Dietary vitamin D intake has been inversely associated with early menopause; however, no previous studies have evaluated risk with regard to plasma 25-hydroxyvitamin D [25(OH)D] concentrations.

Objective

We prospectively evaluated associations of total and free 25(OH)D and vitamin D-binding protein (VDBP) concentrations and the risk of early menopause in a case-control study nested within the Nurses' Health Study II (NHS2). We also considered associations of 25(OH)D and VDBP with anti-Müllerian hormone (AMH) concentrations.

Methods

The NHS2 is a prospective study in 116,430 nurses, aged 25-42 y at baseline (1989). Premenopausal plasma blood samples were collected between 1996 and 1999, from which total 25(OH)D and VDBP concentrations were measured and free 25(OH)D concentrations were calculated. Cases experienced menopause between blood collection and age 45 y (n = 328) and were matched 1:1 by age and other factors to controls who experienced menopause after age 48 y (n = 328). Conditional logistic regression models were used to estimate ORs and 95% CIs for early menopause according to each biomarker. Generalized linear models were used to estimate AMH geometric means according to each biomarker.

Results

After adjusting for smoking and other factors, total and free 25(OH)D were not associated with early menopause. Quartile 4 compared with quartile 1 ORs were 1.04 (95% CI: 0.60, 1.81) for total 25(OH)D and 0.70 (95% CI: 0.41, 1.20) for free 25(OH)D. 25(OH)D was unrelated to AMH concentrations. VDBP was positively associated with early menopause; the OR comparing the highest with the lowest quartile of VDBP was 1.80 (95% CI: 1.09, 2.98).

Conclusions

Our findings suggest that total and free 25(OH)D are not importantly related to the risk of early menopause. VDBP may be associated with increased risk, but replication is warranted.

Addition of a polygenic risk score, mammographic density, and endogenous hormones to existing breast cancer risk prediction models: A nested case-control study

BACKGROUND

No prior study to our knowledge has examined the joint contribution of a polygenic risk score (PRS), mammographic density (MD), and postmenopausal endogenous hormone levels-all well-confirmed risk factors for invasive breast cancer-to existing breast cancer risk prediction models.

METHODS AND FINDINGS

We conducted a nested case-control study within the prospective Nurses' Health Study and Nurses' Health Study II including 4,006 cases and 7,874 controls ages 34-70 years up to 1 June 2010. We added a breast cancer PRS using 67 single nucleotide polymorphisms, MD, and circulating testosterone, estrone sulfate, and prolactin levels to existing risk models. We calculated area under the curve (AUC), controlling for age and stratified by menopausal status, for the 5-year absolute risk of invasive breast cancer. We estimated the population distribution of 5-year predicted risks for models with and without biomarkers. For the Gail model, the AUC improved (p-values < 0.001) from 55.9 to 64.1 (8.2 units) in premenopausal women (Gail + PRS + MD), from 55.5 to 66.0 (10.5 units) in postmenopausal women not using hormone therapy (HT) (Gail + PRS + MD + all hormones), and from 58.0 to 64.9 (6.9 units) in postmenopausal women using HT (Gail + PRS + MD + prolactin). For the Rosner-Colditz model, the corresponding AUCs improved (p-values < 0.001) by 5.7, 6.2, and 6.5 units. For estrogen-receptor-positive tumors, among postmenopausal women not using HT, the AUCs improved (p-values < 0.001) by 14.3 units for the Gail model and 7.3 units for the Rosner-Colditz model. Additionally, the percentage of 50-year-old women predicted to be at more than twice 5-year average risk (≥2.27%) was 0.2% for the Gail model alone and 6.6% for the Gail + PRS + MD + all hormones model. Limitations of our study included the limited racial/ethnic diversity of our cohort, and that general population exposure distributions were unavailable for some risk factors.

CONCLUSIONS

In this study, the addition of PRS, MD, and endogenous hormones substantially improved existing breast cancer risk prediction models. Further studies will be needed to confirm these findings and to determine whether improved risk prediction models have practical value in identifying women at higher risk who would most benefit from chemoprevention, screening, and other risk-reducing strategies.

A prospective analysis of circulating saturated and monounsaturated fatty acids and risk of non-Hodgkin lymphoma

Circulating saturated (SFA) and monounsaturated fatty acids (MUFA), which are predominantly derived from endogenous metabolism, may influence non-Hodgkin lymphoma (NHL) risk by modulating inflammation or lymphocyte membrane stability. However, few biomarker studies have evaluated NHL risk associated with these fats. We conducted a prospective study of 583 incident NHL cases and 583 individually matched controls with archived pre-diagnosis red blood cell (RBC) specimens in the Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS). RBC membrane fatty acid levels were measured using gas chromatography. Using multivariable logistic regression, we estimated odds ratios (OR) and 95% confidence intervals (CI) for risk of NHL and major NHL subtypes including T cell NHL (T-NHL), B cell NHL (B-NHL) and three individual B-NHLs: chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma. RBC SFA and MUFA levels were not associated with NHL risk overall. However, RBC very long chain SFA levels (VLCSFA; 20:0, 22:0, 23:0) were inversely associated with B-NHLs other than CLL/SLL; ORs (95% CIs) per standard deviation (SD) increase in level were 0.81 (0.70, 0.95) for 20:0, 0.82 (0.70, 0.95) for 22:0 and 0.82 (0.70, 0.96) for 23:0 VLCSFA. Also, both VLCSFA and MUFA levels were inversely associated with T-NHL [ORs (95% CIs) per SD: VLCSFA, 0.63 (0.40, 0.99); MUFA, 0.63 (0.40, 0.99)]. The findings of inverse associations for VLCSFAs with B-NHLs other than CLL/SLL and for VLCSFA and MUFA with T-NHL suggest an influence of fatty acid metabolism on lymphomagenesis.

Testosterone Pathway Genetic Polymorphisms in Relation to Primary Open-Angle Glaucoma: An Analysis in Two Large Datasets

Purpose

Sex hormones may be associated with primary open-angle glaucoma (POAG), although the mechanisms are unclear. We previously observed that gene variants involved with estrogen metabolism were collectively associated with POAG in women but not men; here we assessed gene variants related to testosterone metabolism collectively and POAG risk.

Methods

We used two datasets: one from the United States (3853 cases and 33,480 controls) and another from Australia (1155 cases and 1992 controls). Both datasets contained densely called genotypes imputed to the 1000 Genomes reference panel. We used pathway- and gene-based approaches with Pathway Analysis by Randomization Incorporating Structure (PARIS) software to assess the overall association between a panel of single nucleotide polymorphisms (SNPs) in testosterone metabolism genes and POAG. In sex-stratified analyses, we evaluated POAG overall and POAG subtypes defined by maximum IOP (high-tension [HTG] or normal tension glaucoma [NTG]).

Results

In the US dataset, the SNP panel was not associated with POAG (permuted P = 0.77), although there was an association in the Australian sample (permuted P = 0.018). In both datasets, the SNP panel was associated with POAG in men (permuted P ≤ 0.033) and not women (permuted P ≥ 0.42), but in gene-based analyses, there was no consistency on the main genes responsible for these findings. In both datasets, the testosterone pathway association with HTG was significant (permuted P ≤ 0.011), but again, gene-based analyses showed no consistent driver gene associations.

Conclusions

Collectively, testosterone metabolism pathway SNPs were consistently associated with the high-tension subtype of POAG in two datasets.