Urinary concentrations of estrogens and estrogen metabolites and smoking in caucasian women

Factors affecting age at menopause and their relationship with ovarian reserve: a comprehensive review

OBJECTIVE

The aim of this article was to discuss all the factors affecting the age at menopause and their correlation with ovarian reserve.

MATERIALS AND METHODS

A narrative review of original articles was performed using PubMed until December 2023. The following keywords were used to generate the list of citations: 'menopause', 'ovarian reserve' 'oocytes quality and quantity', 'ovarian ageing'.

RESULTS

Menopause is the final step in the process of ovarian ageing and is influenced by the oocyte pool at birth. Conditions that accelerate follicle depletion during the reproductive lifespan lead to premature ovarian insufficiency (POI) and premature ovarian failure (POF), while a higher ovarian reserve is associated with a delayed time to menopause. Reproductive history, sociodemographic, lifestyle and iatrogenic factors may impact ovarian reserve and the age at menopause.

CONCLUSIONS

Some factors affecting the age at menopause are modifiable and the risks of early menopause may be preventable. We hypothesise that by addressing these modifiable factors we may also preserve ovarian reserve. However, further interventional studies are needed to evaluate the effects of the described strategies on ovarian reserve.

Sex Differences in Oxidative Stress-Mediated Reductions in Microvascular Endothelial Function in Young Adult e-Cigarette Users

BACKGROUND

Chronic electronic-cigarette (EC) use is reported to decrease vascular endothelial function. However, the mechanism(s) mediating this reduction remain unclear. In this study, we examined endothelium- and NO-dependent dilation, and the role of oxidative stress in attenuating these responses, in healthy young EC users (n=20, 10 males/10 females) compared with healthy controls (n=20, 10 males/10 females). We hypothesized that EC would have reduced endothelium- and NO-dependent dilation and administration of the superoxide scavenger tempol would increase these responses in EC. We further hypothesized that female EC would have the greatest reductions in endothelium- and NO-dependent dilation.

METHODS

We assessed microvascular endothelium-dependent vasodilator function in vivo by measurement of cutaneous vascular conductance (%CVCmax) responses to a standardized local heating protocol in control and 10 μM tempol-treated sites. After full expression of the local heating response, 15 mM NG-nitro-L-arginine methyl ester (NO synthase inhibition) was perfused.

RESULTS

EC had significantly reduced endothelium- (73±15 versus 87±9%CVCmax; P<0.001) and NO-dependent (48±17% versus 62±15%; P=0.011) dilation. Tempol perfusion increased endothelium-dependent (84±12%CVCmax P=0.01) and NO-dependent (63±14% P=0.005) dilation in EC but had no effect in healthy control. Within female sex, EC had lower endothelium-dependent (71±13 versus 89±7%CVCmax; P=0.002) and NO-dependent (50±6 versus 69±11%; P=0.005) dilation compared with healthy control, and tempol augmented endothelium-dependent (83±13%CVCmax; P=0.002) and NO-dependent (62±13%; P=0.015) dilation. There were no group or treatment differences within male sex.

CONCLUSION

Healthy young adult EC users have reduced microvascular endothelium-dependent and NO-dependent dilation, driven by greater reductions in female EC users, and mediated in part by superoxide.

Association between periodontitis and osteoporosis in United States adults from the National Health and Nutrition Examination Survey: a cross-sectional analysis

OBJECTIVE

This cross-sectional study aimed to investigate the association between periodontitis and osteoporosis among US adults as well as the subgroup of menopausal women.

BACKGROUND

Periodontitis and osteoporosis are both chronic inflammatory diseases characterized by local or systemic bone resorption. Since they share many risk factors, and the significant decrease in estrogen along with menopause is unfavorable for both diseases, it's reasonable to assume that there exists some links between the two diseases, especially during the menopause.

METHODS

We analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2009-2010 and 2013-2014. Periodontitis (defined according to the CDC/AAP definition) and osteoporosis (assessed by the dual-energy radiation absorptiometry) data were available for 5736 participants, and 519 subjects were enrolled in the subgroup of menopausal women aged 45-60 years old. We used binary logistic regression analysis to examine the association between the two diseases both in crude and fully adjusted model.

RESULTS

In the fully adjusted model, osteoporosis was significantly associated with an increased risk of periodontal disease (OR:1.66, 95% CI: 1.00-2.77) in the whole population. As to the subgroup of menopausal women, osteoporosis group had an adjusted OR of 9.66 (95% CI: 1.13-82.38) for developing severe periodontitis in the fully adjusted model.

CONCLUSIONS

Osteoporosis is significantly associated with periodontitis and the association is even more pronounced in menopausal women with severe periodontitis.

Commonalities in Metabolic Reprogramming between Tobacco Use and Oral Cancer

Tobacco use is a major public health concern and is linked to myriad diseases, including cancer. The link between tobacco use and oral cancer, specifically, is very strong, making tobacco use one of the primary risk factors for oral cancer. While this association is well known, the underlying biochemical changes that result from tobacco use, and how this links to metabolic phenotypes of oral cancer, is not well understood. To address this knowledge gap, a combination of literature reviews and metabolomics studies were performed to identify commonalities in metabolic perturbations between tobacco use and oral cancers. Metabolomics analysis was performed on pooled reference urine from smokers and non-smokers, healthy and malignant oral tissues, and cultured oral cells with or without treatment of the well-known tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Alterations in amino acid metabolism, carbohydrates/oxidative phosphorylation, fatty acid oxidation, nucleotide metabolism, steroid metabolism, and vitamin metabolism were found to be shared between tobacco use and oral cancer. These results support the conclusion that tobacco use metabolically reprograms oral cells to support malignant transformation through these pathways. These metabolic reprogramming events may be potential targets to prevent or treat oral cancers that arise from tobacco use.

A Systematic Review and Meta-Analysis of Smoking and Circulating Sex Hormone Levels Among Premenopausal Women

It is established that higher pre-diagnostic circulating androgen and estrogen levels are associated with increased breast cancer risk in premenopausal and postmenopausal women. Pooled analyses in postmenopausal women report higher androgen and estrogen levels in current heavy cigarette smokers compared to nonsmokers. However, evidence among premenopausal women has been inconsistent. We conducted a systematic review and meta-analysis to estimate differences in standardized mean hormone levels among current premenopausal smokers compared to nonsmokers. We reviewed and collated publications with sex hormone levels by smoking status among healthy, premenopausal women who were nonusers of exogenous hormones, including oral contraceptives, using PubMed through December 2019. A random effects meta-analysis was conducted to combine the standardized mean differences (SMD) and 95% confidence intervals (CIs) for estradiol, progesterone, testosterone, dehydroepiandrosterone, dehydroepiandrosterone-sulfate, and sex hormone-binding globulin by smoking status. Findings were summarized by menstrual cycle phase and overall. Nineteen published peer-reviewed articles were included. Significantly increased testosterone levels among smokers compared to nonsmokers were identified from cross-sectional studies with varied menstrual phase timing (SMD 0.14; 95% CI 0.0005, 0.29) and significantly increased dehydroepiandrosterone-sulfate levels were found over all phases (SMD 0.12; 95% CI 0.01, 0.22). However, substantial heterogeneity existed in these studies. This meta-analysis suggests that smoking may increase blood androgen levels in healthy premenopausal women which may increase breast cancer risk; however, the differences were modest. Larger and covariate-adjusted studies with standardized collection over the menstrual cycle are needed to better understand this relationship and to reduce heterogeneity. Implications: Existing research has described associations between high pre-diagnostic estradiol and androgen levels with breast cancer risk among premenopausal women and has established active smoking as a breast cancer risk factor. However, the smoking and circulating sex hormone associations among premenopausal women remain inadequately studied. In this meta-analysis, we identified an association between smoking and higher mean testosterone and dehydroepiandrosterone-sulfate levels with consideration of menstrual phase, providing additional information on smoking's potential pathway to premenopausal breast cancer.

Association between Serum Cotinine Levels and Bone Mineral Density: An Analysis of the National Health and Nutrition Examination Survey (NHANES)

PURPOSE

To investigate the relationship between serum cotinine and lumbar bone mineral density (BMD) among 7905 participants aged 30 years and over.

METHOD

A total of 3945 men and 3960 women from the National Health and Nutrition Examination Survey 2011-2018 were included in this cross-sectional analysis. Independent variable was serum cotinine, which is a biomarker of cigarette exposure. The outcome variable was lumbar BMD. We investigated the associations of serum cotinine levels and lumbar BMD using multivariable linear regression models.

RESULTS

Serum cotinine concentration was negatively associated with lumbar BMD after adjustment of relevant covariables (β = -0.039, 95% CI: -0.078 to -0.014, P = 0.005). However, in the subgroup analysis stratified by gender, this negative association remained only in women (β = -0.072, 95% CI: -0.132 to -0.012, P = 0.019).

CONCLUSION

Our study suggested that elevated serum cotinine level correlated with decreased lumbar BMD, especially in women. This finding indicated that reducing cigarette exposure and maintaining serum cotinine at a low level may be beneficial to bone health for adults.

Maternal phthalate and phthalate alternative metabolites and urinary biomarkers of estrogens and testosterones across pregnancy

BACKGROUND/OBJECTIVES

Pregnant women are ubiquitously exposed to phthalates from food packaging materials and personal care products. Phthalates alter estrogen and testosterone concentrations in experimental models, but their ability to impact these hormones in human pregnancy is not well characterized.

METHODS

We recruited women ages 18-40 into the Illinois Kids Development Study (I-KIDS) in early pregnancy. Participants provided up to 5 first-morning urine samples across pregnancy (8-40 weeks gestation) that we pooled for quantification of 19 phthalate or phthalate alternative metabolites. Either individual (ng/mL) or molar sums (nmol/mL) of metabolites were used as exposure biomarkers. We summed urinary concentrations (ng/mL) of eight major estrogen (SumEstrogens) and two major testosterone (SumTestosterones) metabolites measured at median 13, 28, and 34 weeks gestation. We also estimated the ratio of estrogens-to-androgens. Linear mixed-effects models assessed relationships of phthalates/alternatives as continuous measures or as concentration quartiles with SumEstrogens, SumTestosterones, and the Estrogen/Androgen ratio in 434 women. In our models, we controlled for age, race, education, parity, smoking in the first trimester, pre-pregnancy body mass index, diet quality, conception season, fetal sex, and gestational age at hormone assessment. We also explored whether gestational age at hormone assessment or fetal sex modified these associations. All biomarkers and outcomes were specific gravity-adjusted, and continuous exposures and outcomes were also natural log-transformed.

RESULTS

Most participants were non-Hispanic white (80.9%), college educated (82.2%), and had urinary phthalate/alternative metabolite concentrations similar to those of reproductive-aged U.S. women. Overall, select phthalate metabolites were positively associated with SumEstrogens and SumTestosterones, but negatively associated with the Estrogen/Androgen ratio. For example, SumEstrogens was 5.1% (95%CI: 1.8, 8.5) higher with every 2-fold increase in sum of di(2-ethylhexyl) phthalate metabolites, while SumTestosterones was 7.9% (95%CI: 1.0, 15.3) higher and Estrogen/Androgen ratio was -7.7% (95%CI: -13.6, -1.4) lower with every 2-fold increase in monoethyl phthalate. However, phthalate alternatives were only positively associated with SumEstrogens, which was 2.4% (95%CI: 0.4, 4.5) and 3.2% (95%CI: 0.7, 5.8) higher with every 2-fold increase in sum of di(isononyl) cyclohexane-1,2-dicarboxylate metabolites and sum of di(2-ethylhexyl) terephthalate metabolites, respectively. Gestational age- and fetal sex-specific associations were only consistently observed for associations of phthalates/alternatives with SumEstrogens, where associations were strongest in mid-to-late pregnancy in women carrying females.

CONCLUSION

Phthalates/alternatives may impact gestational hormones, with potential for gestational age- and fetal sex-specific associations. Whether maternal urinary estrogens and testosterones mediate associations of phthalates/alternatives with pregnancy and fetal outcomes merits further investigation.

Urinary equol levels are positively associated with urinary estradiol excretion in women

Isoflavones found in soy products are a promising class of nutrients that may have a positive effect on human health. In particular, the phytoestrogen metabolite equol is associated with a reduced risk of developing female hormone-related diseases. However, the effect of equol on estrogen remains unclear. Equol can modify blood and urinary estradiol (E2) levels. The aim of this cross-sectional study was to examine the associations between urinary estrogen levels, equol levels, and equol production status in Japanese women. We analyzed urine samples from 520 women by gas chromatography-mass spectrometry. Urinary E2 and 4-hydroxylated E2 levels were higher in equol producers (EQP) than in non-EQPs (P < 0.0001 and P=0.00112, respectively). After adjusting for age and tobacco use by analysis of covariance, the association remained significant (β = 0.299, P < 0.0001). Analysis of covariance demonstrated that equol levels in urine were also positively associated with urinary E2 (β = 0.597, P < 0.0001). The log equol concentration showed a significant, but moderate, negative association with the serum E2 concentration (β = − 0.0225, P = 0.0462). Our findings suggest that equol may promote urinary E2 excretion and modify blood E2 levels in women.

Human beta-defensin-1 rs2738047 polymorphism is associated with shisha smoking risk among Saudi population

Human β-defensin (HBD), a member of the antimicrobial peptides, is essential for respiratory epithelial cells' microbial defense, and is affected by cigarette smoking (CS). Its expression is upregulated by stimulation from microbes or inflammation. Genetic polymorphisms in the HBD-1 gene have been implicated in the development of various smoking-related diseases, including chronic obstructive pulmonary disease and asthma. Thus, we sought to analyze possible associations between HBD-1 single-nucleotide polymorphism (SNP) in HBD-1 gene and CS in ethnic Saudi Arabian subjects. Variants rs1047031 (C/T), rs1799946 (C/T), rs2738047 (C/T), and rs11362 (C/T) were investigated by genotyping 575 blood specimens from males and females, smokers/non-smokers: 288/287. The CT and CT+TT genotypes of rs1799946 presented an ~5-fold increased correlation with CS among the female smokers, compared with the female controls (OR = 5.473, P = 0.02003; and OR = 5.211, P = 0.02028, respectively), an observation similar to rs11362 SNP in female smokers, but with protective effects in TT genotype, compared with the CC reference allele (OR = 0.143, P = 0.04368). In shisha smokers, the heterozygous CT and the CT/TT genotype of rs2738047 polymorphism showed the same results with ~3-fold increased correlation with CS (OR = 2.788; P = 0.03448), compared with the cigarette smokers category. No significant association was shown in genotypic distributions and allelic frequencies of rs1047031. Further investigations, including large study samples, are required to investigate the effects of shisha on human beta-defensin expression and protein levels.

The protective effects of the methylenetetrahydrofolate reductase rs1801131 variant among Saudi smokers

Methylenetetrahydrofolate reductase (MTHFR) polymorphism plays a fundamental role in susceptibility to various diseases, including cancers and autoimmune diseases. In the current study, we aimed to compare genotype and allele frequency variations of rs1801131, one of the most common variants found in the MTHFR gene, among Saudi smokers and non-smokers. We hypothesized that genetic variations of this gene are responsible for many diseases, particularly those caused by cigarette smoking (CS) such as pulmonary diseases, oral cancer and lung cancer. We performed a case-control study on a sample of 235 healthy smokers and 239 healthy non-smokers in Saudi Arabia. The rs1801131 SNP genotypes were determined using a genotyping assay and multiple in silico algorithmic software programs were used to identify the effects and structural functions of the rs1801131 (Glu429Ala) mutation. Using chi-squared tests, we found that, among smokers, TG and GG genotype carriers had 0.209-fold (OR = 0.209, P < 0.005) and 0.427-fold (OR = 0.427, P = 0.003) lower risks of CS-related disease compared to TT reference genotypes. In addition, this protective effect was observed in Saudi smokers independent of age, gender, types of smoking, duration, and average daily smoking consumption. Filling a research gap by exploring this topic in the Saudi population, the current findings indicate that genotype and allele distributions of MTHFR rs1801131 polymorphism present fundamental protective effects against the risk of CS-related disease. These findings should be verified in future studies with larger sample sizes, different ethnicities, and patients suffering from CS-related diseases, such as oral cancer and lung cancer.

[Prevalence of Menstrual Disorders according to Body Mass Index and Lifestyle Factors: The National Health Insurance Service-National Health Screening Cohort in Korea, 2009~2016]

PURPOSE

This study was performed to identify the prevalence of menstrual disorders in Korean women based on body mass index (BMI) and lifestyle factors, by utilizing the Korean National Health Insurance Database.

METHODS

A retrospective observational study design was used for the secondary data analysis. Data of women aged 15 to 49 years who were diagnosed with menstrual disorders were extracted from The National Health Insurance Service-National Health Screening Cohort in Korea from 2009 to 2016. The age-standardized prevalence rate of menstrual disorders was calculated using SAS version 9.4, and a Chi-square test and Cochran-Armitage test were performed.

RESULTS

In total, 2,219,445 cases were extracted from the database. The prevalence of menstrual disorders significantly increased from 8.6% to 11.6% (Z=135.16, p for trend <.001) over the past eight years. In particular, it was higher in underweight women than in women with normal weight across all years (Z=-4.18~-14.72, p<.001). Moreover, statistically significant differences in the prevalence of menstrual disorders were found to be associated with drinking and smoking in all years and with physical activity levels in part (p<.05~.001).

CONCLUSION

These findings present compelling evidence on the prevalence of menstrual disorders based on a national database. Since the prevalence of menstrual disorders has steadily increased and differs based on BMI and lifestyle factors, educational and clinical interventions are necessary to promote risk awareness and appropriate behavioral changes among Korean women.

Urinary bisphenol A and its interaction with ESR1 genetic polymorphism associated with non-small cell lung cancer: findings from a case-control study in Chinese population

Bisphenol A (BPA), a well-known endocrine disruptor, was reported to promote migration and invasion of lung cancer cells, but findings in human study is absent. A case-control study in Chinese population was conducted to evaluate the association between BPA exposure and non-small cell lung cancer (NSCLC), and explore the interaction between BPA exposure and estrogen-related genetic polymorphism on NSCLC. BPA concentrations were measured in urine samples using an UHPLC-MS method and rs2046210 in estrogen receptor α (ESR1) gene was genotyped by TaqMan genotyping system. Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for the association analyses. As a result, 615 NSCLC cases and 615 healthy controls were enrolled from Wuhan, central China. The mean age was 58.0 (SD: 7.9) years old for controls and 59.2 (SD: 8.8) years old for cancer cases. The creatinine-adjusted BPA levels were significantly higher in NSCLC cases than that in healthy controls (median: 0.97 vs 0.73 μg/L, P < 0.001). Exposure to high levels of BPA was significantly associated with NSCLC (adjusted OR = 1.91, 95%CI: 1.39-2.62, P < 0.001 for the highest quartile). We also observed a shallow concave dose-response relationship about the overall association between BPA and NSCLC. Moreover, interaction analyses showed that BPA exposure interacted multiplicatively with rs2046210, with a marginal P value (P = 0.049), to contribute to NSCLC. In conclusion, exposure to high levels BPA may be associated with NSCLC and the relationship may be modified by genetic polymorphism in ESR1.

The Impact of Smoking on Bone Metabolism, Bone Mineral Density and Vertebral Fractures in Postmenopausal Women

BACKGROUND

Smoking is recognized among the risk factors for osteoporosis, but only few studies have comprehensively explored its influence on bone metabolism and strength. We aimed to evaluate smoking effects on calcium-phosphate metabolism, bone mineral density (BMD) and fracture risk in postmenopausal women.

METHODS

Our sample included 1067 postmenopausal women who arrived to our osteoporosis outpatient clinic. Anamnestic data, smoking habits (categorized as never, former, and current; and by smoking intensity and duration), biochemical parameters, lumbar/femoral BMD, and presence of vertebral fractures were recorded. In a subsample of 357 women, the changes in BMD after a 2-yr follow-up period were also assessed.

RESULTS

Current smokers had shorter reproductive age, lower body mass index, and higher prevalence of heavy alcohol consumption than former/never smokers. They also had lower PTH values and weaker linear association between serum vitamin D and parathyroid hormone (current β = -0.11[SE = 0.004]; former β = -0.14[SE = 0.01]; never β = -0.20[SE = 0.003]; p < 0.01 for all). Baseline BMD did not reflect differences based on smoking habits, duration or intensity. However, after 2 years, only current smokers significantly worsened in femural BMD. After adjustment for confounders, the chance of having sustained vertebral fractures at the first evaluation increased by 74% (95% confidence interval:1.07-2.83) in current compared with never smokers, especially among heavy smokers.

CONCLUSIONS

Smoking may negatively affect bone by inhibiting vitamin D-parathyroid hormone axis, reducing estrogen exposure, promoting risky health behaviors, and accelerating bone loss, especially at the femur. No significant differences were observed in these outcomes among former smokers, suggesting that quitting smoking has beneficial effects on bone health.

Evaluation of endocrine disruption and gestational disorders in women residing in areas with intensive pesticide application: An exploratory study

The proximity to areas of intensive pesticide application is a risk factor that favors xenobiotic exposure. Pesticides may interfere with hormonal function and cause alterations in the reproductive system, pregnancy complications, and adverse fetal development. We evaluated potential endocrine disruption and the evolution of the third trimester of pregnancy in women residing in a rural area of Argentina with intense pesticide applications, and the characteristics of their newborns. Blood samples were collected from healthy women in the third trimester of pregnancy during the pesticide spraying (SP) (n = 26) and nonspraying (NSP) (n = 27) periods. Plasma cholinesterase activity and cortisol and DHEA-S levels were lower in SP than in NSP. The percentage of preterm premature rupture of membranes was higher in SP than in NSP. Macrosomia at birth was17% in both periods. This study reinforces the importance of preventing potential cases of cumulative toxicity during the perinatal period through monitoring and epidemiological studies.

Sex-specific risk factors for cardiovascular disease in women-making cardiovascular disease real

PURPOSE OF REVIEW

Sex-specific differences in pathophysiology, prevalence, and impact of cardiovascular disease (CVD) risk factors may explain the high cardiovascular mortality rates in women.

RECENT FINDINGS

We review the sex differences in traditional risk factors (dyslipidemia, hypertension, diabetes, and smoking) and nontraditional risk factors (menopause and hormones, pregnancy, inflammation and autoimmune diseases, anemia, depression, and migraines) and their prognostic and therapeutic implications.

SUMMARY

Recent research indicates that with respect to traditional risk factors such as dyslipidemia, hypertension, diabetes, and smoking, women appear to have a similar risk of CVD when compared to men. The risk is accelerated after menopause, possibly because of vascular and lipid profile changes. Pregnancy offers a unique opportunity and window to screen otherwise healthy women who may be at an increased risk of CVD in the future. Clinicians should be aware of other novel risk factors including inflammation, anemia, migraines, and depression, and further studies are warranted in order to identify therapeutic implications for these conditions and CVD risk.

Demographic, lifestyle, and reproductive risk factors for ectopic pregnancy

OBJECTIVE

To evaluate the relationship between demographic, lifestyle, and reproductive factors and the risk of ectopic pregnancy (EP).

DESIGN

Prospective cohort.

SETTING

United States.

PATIENT(S)

Nurses' Health Study II cohort comprising 41,440 pregnancies from 22,356 women.

INTERVENTION(S)

Demographic, lifestyle, and reproductive factors self-reported in 1989 then updated every 2 years. Multivariable log-binomial regression models with generalized estimating equations were used to estimate adjusted risk ratios (aRR).

MAIN OUTCOME MEASURE(S)

Ectopic pregnancy.

RESULT(S)

Incident EP was reported in 411 (1.0%) pregnancies. Former and current smokers had 1.22 (95% confidence interval [CI], 0.97-1.55) and 1.73 (95% CI, 1.28-2.32) times, respectively, the risk of EP compared with never smokers. The risk of EP 10 years after quitting was similar to never smokers (aRR 0.90; 95% CI, 0.60-1.33). Women consuming ≥10 g/day of alcohol had 1.50 (95% CI, 1.08-2.09) times the risk of EP compared with never consumers. In utero exposure to diethylstilbestrol (aRR 3.55; 95% CI, 2.51-5.01), earlier initiation of oral contraceptives (aRR 2.64; 95% CI, 1.70-4.09 for <16 years vs. never), intrauterine device use (aRR 3.99; 95% CI, 2.06-7.72), or history of infertility (aRR 3.03; 95% CI, 2.48-3.71) or tubal ligation (aRR 16.27; 95% CI, 11.76-22.53) also were associated with a higher risk of EP.

CONCLUSION(S)

Women who were current or former smokers, consumed ≥10 g/day of alcohol, were exposed to diethylstilbestrol in utero, initiated oral contraceptives at earlier than age 16 years (which may be a marker of riskier sexual behaviors), and who had a history of infertility, intrauterine device use, or tubal ligation had a higher risk of EP.

Effect of the thymine-DNA glycosylase rs4135050 variant on Saudi smoker population

Background

Thymine‐DNA glycosylase (TDG) is an essential DNA‐repair enzyme which works in both epigenetic regulation and genome maintenance. It is also responsible for efficient correction of multiple endogenous DNA lesions which occur commonly in mammalian genomes. Research of genetic variants such as SNPs, resulting in disease, is predicted to yield clinical advancements through the identification of sensitive genetic markers and the development of disease prevention and therapy. To that end, the main objective of the present study is to identify the possible interactions between cigarette smoking and the rs4135050 variant of the TDG gene, situated in the intron position, among Saudi individuals.

Methods

TDG rs4135050 (A/T) was investigated by genotyping 239, and 235 blood specimens were obtained from nonsmokers and smokers of cigarette respectively.

Results

T allele frequency was found which showed a significant protective effect on Saudi male smokers (OR = 0.64, p = 0.0187) compared to nonsmoking subjects, but not in female smokers. Furthermore, smokers aged less than 29 years, the AT and AT+TT genotypes decreased more than four times the risk of initiation of smoking related‐diseases compare to the ancestral AA homozygous genotype. Paradoxically, the AT (OR = 3.88, p = 0.0169) and AT+TT (OR = 2.86, p = 0.0420) genotypes were present at a higher frequency in smoking patients aged more than 29 years as compared to nonsmokers at the same ages.

Conclusion

Depending on the gender and age of patients, TDG rs4135050 may provide a novel biomarker for the early diagnosis and prevention of several diseases caused by cigarette smoking.

Estrogen Metabolism in Premenopausal Women Is Related to Early Life Body Fatness

Background: Estrogen metabolism in premenopausal women may be related to early life body fatness.Methods: Premenopausal women participating in the Nurses' Health Study II recalled their body fatness at ages 5, 10, and 20 years using a validated 9-level pictogram. Fifteen estrogens and estrogen metabolites (EM) were measured using LC/MS-MS in luteal phase urines from 603 women ages 32-54 years. Geometric means of individual EM, metabolic pathway groups, and pathway ratios were examined by body fatness categories using linear mixed models.Results: Body fatness at each age was inversely associated with adult concentrations of all EM combined, parent estrogens (estrone, estradiol), and the 2-hydroxylation pathway. Women in the top (vs. bottom) category of body fatness at age 10 had 21% lower levels of all EM (Ptrend = 0.003), 24% lower parent estrogens (Ptrend = 0.002), and 36% lower 2-pathway (Ptrend = 0.0003). Body fatness at age 10 was inversely associated with 2-catechols (35% lower, Ptrend = 0.0004) and 2-methylated catechols (30% lower, Ptrend = 0.002). After adjusting for premenopausal body mass index (BMI), these associations remained inverse but were attenuated; only parent estrogens remained statistically significant (21% lower, Ptrend = 0.01). Body fatness at ages 5 and 20 were similarly, but more weakly, associated with estrogen pathways.Conclusions: Estimates of body fatness during early life were inversely associated with premenopausal levels of all EM combined, parent estrogens, and 2-pathway estrogen metabolites. These relationships were not fully explained by adult BMI.Impact: These findings inform investigations of diseases linked to early life body fatness and estrogen metabolism. Cancer Epidemiol Biomarkers Prev; 27(5); 585-93. ©2018 AACR.

Modification of the Associations Between Duration of Oral Contraceptive Use and Ovarian, Endometrial, Breast, and Colorectal Cancers

IMPORTANCE

Although oral contraceptive (OC) use is common, the influence of OC use on carcinogenesis is not fully understood. A recent Agency for Healthcare Research and Quality report identified a need to understand the consistency of OC use and cancer associations across subpopulations, including smokers and obese women.

OBJECTIVE

To determine whether associations between duration of OC use and risk of specific cancers were modified by lifestyle characteristics.

DESIGN, SETTING, AND PARTICIPANTS

The prospective NIH-AARP Diet and Health Study (enrolled 1995-1996, followed until 2011), with population-based recruitment of AARP members in 6 states and 2 metropolitan areas. All analyses included at least 100 000 women who reported OC use at enrollment. We identified 1241 ovarian, 2337 endometrial, 11 114 breast, and 3507 colorectal cancer cases during follow-up. Data analysis was performed between September 2016 and April 2017.

EXPOSURES

Duration of OC use (never or <1 year [reference], 1-4, 5-9, or ≥10 years).

MAIN OUTCOMES AND MEASURES

Development of ovarian, endometrial, breast, and colorectal cancers. We examined effect modification by modifiable lifestyle characteristics: cigarette smoking, alcohol consumption, body mass index (BMI), and physical activity. We used Cox models adjusted for age, race, age at menarche, and the modifiers of interest.

RESULTS

The analytic population was aged 50 to 71 years (median, 62 years) at enrollment and largely white (91%) and postmenopausal (96%). For ovarian cancer, OC use-associated risk reductions strengthened with duration of use (long-term OC use [≥10 years] HR, 0.60; 95% CI, 0.47-0.76; P < .001 for trend) and were similar across modifiable lifestyle factors. Risk reductions for endometrial cancer strengthened with duration of use (long-term OC use HR, 0.66; 95% CI, 0.56-0.78; P < .001 for trend); the most pronounced reductions were among long-term OC users who were smokers (HR, 0.47; 95% CI, 0.25-0.88), had obese BMIs (0.36; 95% CI, 0.25-0.52), and who exercised rarely (HR, 0.40; 95% CI, 0.29-0.56). Associations between OC use and breast and colorectal cancers were predominantly null.

CONCLUSIONS AND RELEVANCE

Long-term OC use is consistently associated with reduced ovarian cancer risk across lifestyle factors. We observed the greatest risk reductions for endometrial cancer among women at risk for chronic diseases (ie, smokers, obese BMI). Oral contraceptive use may be beneficial for chemoprevention for a range of women with differing baseline cancer risks.

Hormonal factors and pancreatic cancer risk in women: The Malmö Diet and Cancer Study

The incidence of pancreatic cancer is leveling between sexes. Smoking, high age and heredity are established risk factors, but evidence regarding the influence of hormonal factors is unclear. In this study, we investigated the associations of reproductive factors, use of oral contraceptives (OC) and hormone replacement therapy (HRT) with pancreatic cancer risk in the Malmö Diet and Cancer Study, a prospective, population‐based cohort encompassing 17,035 women. Up until 31 December 2015, 110 women were identified with incident pancreatic cancer through the Swedish Cancer Registry. Higher age at menarche was significantly associated with pancreatic cancer risk (age‐adjusted [hazard ratio] HR = 1.17; 95% confidence interval [CI] 1.04–1.32, and fully adjusted HR = 1.17; 95% CI 1.04–1.32). Ever use of OC was not significantly associated with pancreatic cancer risk but ever use of HRT was significantly associated with a decreased risk of pancreatic cancer (age‐adjusted HR = 0.47, 95% CI 0.23–0.97, and fully adjusted HR = 0.48, 95% CI 0.23–1.00), in particular use of estrogen‐only regimen (age‐adjusted HR = 0.21; 95% CI 0.05–0.87 and fully adjusted HR = 0.22; 95% CI 0.05–0.90). Age at menopause or first childbirth, parity and breastfeeding history were not significantly associated with pancreatic cancer risk. Collectively, these findings suggest a protective role of female hormones against pancreatic cancer. Further studies are needed, and potential modifying genetic factors and indirect hazardous effects of smoking should also be considered.

What's new?

Female hormones appear to protect against pancreatic cancer, at least in Sweden. Numerous studies have investigated the relationship between the two, but no clear picture has yet emerged. These authors used data from the Malmö Diet and Cancer study, looking for correlations between hormone levels and cancer risk. They found that a younger start to menstruation—indicating an earlier boost in estrogen—correlated with less chance of developing pancreatic cancer. Use of hormone replacement therapy, particularly estrogen‐only therapy, significantly reduced risk among postmenopausal women. Breastfeeding, oral contraceptive use and parity did not appear to affect pancreatic cancer risk.

Factors associated with menstrual cycle irregularity and menopause

Background

A regular menstrual cycle is an important indicator of a healthy reproductive system. Previous studies reported obesity, stress, and smoking as the factors that are associated with irregular menstruation and early menopause. However, the integrative effects of these modifiable risk factors have not been fully understood. This study aimed to investigate the modifiable risk factors of menstrual cycle irregularity and premature menopause, as well as their individual and combined effects among adult women in Korea.

Method

This study selected adult women aged 19 years and above who had been included in the 2007–2014 Korean National Health and Nutrition Examination Survey. We used a separate dataset to analyze the risk factors of menstrual cycle irregularity and menopause (pre- and postmenopausal women: n = 4788 and n = 10,697, respectively). Univariate and multiple logistic regression analyses were conducted to evaluate the effects of smoking, drinking, obesity, and perceived level of stress on the menstrual cycle and menopause. Both logit and linear models were used in the analyses of the association between smoking and menopausal age. Equivalized household income, marital status, and educational level were considered as covariates. The modifiable risk factor scores were also calculated to integrate the effect of smoking, drinking, and obesity in the analysis.

Result

Results showed that smoking status, pack-year, obesity, and perceived level of stress were significantly associated with irregular menstruation among premenopausal women. Especially, women demonstrating > 3 modifiable risk factor scores had 1.7 times higher risk of having irregular menstruation than those who had a 0 score. Meanwhile, early initiation of smoking (≤19 years) and high pack-year (≥5) were also significantly associated with premature menopause among postmenopausal women.

Conclusion

This study demonstrated that modifiable risk factors, such as smoking, obesity, and stress, were significantly associated with menstrual cycle irregularity. Lifetime smoking was also correlated with early menopause. Our results suggested that healthier lifestyle practices, including, cessation of smoking, weight control, and stress management, were important factors in improving the reproductive health of women throughout life.

Coffee or Tea? A prospective cohort study on the associations of coffee and tea intake with overall and cause-specific mortality in men versus women

Coffee and tea intake have been associated with reduced mortality, but no studies have investigated possible substitution effects. The relationship of mortality with coffee, tea, and substituting coffee with tea was investigated in the Netherlands Cohort Study. In 1986, 120,852 men and women aged 55-69 years provided information on dietary and lifestyle habits. Mortality follow-up until 1996 consisted of linkage to Statistics Netherlands. Multivariate case-cohort analyses were based on 8665 deaths and 3166 subcohort members with complete data on coffee, tea and confounders. Higher coffee intake was significantly, nonlinearly related to lower overall and cause-specific mortality in women. In men, coffee was significantly positively related to cancer and cardiovascular mortality, and inversely to respiratory and other causes of death. Tea intake was significantly, nonlinearly related to lower overall, cancer and cardiovascular mortality in men, but showed no association with mortality in women. In substitution analyses, increasing the proportion tea (replacing coffee with tea) was significantly and nonlinearly related to lower overall, cancer and cardiovascular mortality in men, but in women higher tea proportions were positively associated with overall mortality (and most causes of death). This study suggests that for men, compared to exclusive coffee drinkers, those drinking 30-50% tea showed the lowest mortality; any tea drinking seemed better than only coffee. For women, those who drank exclusively coffee or drinking up to 40% tea had the lowest mortality, but those drinking higher percentages of tea were at increased mortality risk [HR = 1.41 (95% CI 1.01-1.99) for 80-100% tea compared to exclusive coffee drinkers].

Estrogen metabolism in the human lung: impact of tumorigenesis, smoke, sex and race/ethnicity

Previous data from this group demonstrate that the murine lung metabolizes estrogen. Production of the putative carcinogen 4-hydroxyestrogen (4-OHE) is elevated within the lungs of female vs. male mice and accelerated by tobacco smoke. The goal of this study was to determine if the human lung metabolizes estrogen and evaluate the impact of tumor formation, smoke, sex and race/ethnicity on metabolism. Urine and lung tissue (normal, tumor) were obtained from 49 non-small cell lung cancer patients. Healthy postmenopausal Caucasian (n = 19) and Chinese (n = 20) American women (never-smokers) donated urine. Quantitative RT-PCR analyses indicate that multiple estrogen synthesis and metabolism genes are expressed in human bronchoalveolar cells. Estrogen and its metabolites were measured in lung tissue and urine using liquid chromatography/tandem mass spectrometry. Wilcoxon rank tests were used for statistical comparisons. E₁, E₂, E₃ and estrogen metabolites 2-OHE₁, 2-OHE₂, 4-OHE₁, 4-OHE₂, 2-OME₁ and 2-OME₂ were detected at higher levels in tumor vs. adjacent normal tissue and in women vs. men (P < 0.05). The proportion of 4-OHEs was higher in tumors than in normal lung tissue (P < 0.05), and elevated in normal tissue from current- vs. never-smoking women (P = 0.006); similar trends were observed in urine. The proportion of 4-OHEs in the urine of postmenopausal Chinese American women was 1.8-fold higher than that of Caucasian women (P = 0.015). These data indicate that estrogen metabolites are present in the human lung. A shift towards 4-hydroxylation during lung tumorigenesis may contribute to the risk conferred by smoking, sex or race/ethnicity.

A possible dual effect of cigarette smoking on the risk of postmenopausal breast cancer

Smoking seems modestly associated with breast cancer, but the potential dual effect of smoking (with opposing properties: carcinogenic vs anti-estrogenic) is understudied. The relationship between smoking before and after menopause and risk of postmenopausal breast cancer was investigated in the Netherlands Cohort Study (NLCS). In the NLCS, 62,573 women aged 55–69 years provided information on smoking, dietary and other lifestyle habits in 1986. Follow-up for cancer incidence until 2007 (20.3 years) consisted of record linkages with the Netherlands Cancer Registry and the Dutch Pathology Registry PALGA. Multivariate case-cohort analyses were based on 2526 incident breast cancer cases and 1816 subcohort members with complete data on smoking. When smoking during pre- and postmenopausal periods was mutually adjusted for, breast cancer risk was significantly positively associated with premenopausal smoking pack-years, but inversely associated with postmenopausal smoking pack-years, both in a dose-dependent manner. In continuous analyses, the hazard ratios (95% CI) were 1.35 (1.10–1.65), and 0.47 (0.28–0.80) per increment of 20 premenopausal, and postmenopausal pack-years, respectively. The interaction between pre- and postmenopausal pack-years in relation to breast cancer risk was significant (P < 0.001). This study highlights the importance of distinguishing and adjusting for smoking in different life periods, and suggests dual effects of smoking on postmenopausal breast cancer risk.

UPLC-MS/MS method for the determination of tobacco-specific biomarker NNAL, tamoxifen and its main metabolites in rat plasma

Cigarette smoke is known to interact with tamoxifen-metabolizing enzymes and transporters and potentially affect its treatment outcome. 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important metabolite of 4-(methylnitro-samino)-1-(3-pyridyl)-1-butanone (NNK) because it is frequently used as a biomarker to assess human smoke exposure. In order to study the potential pharmacokinetic interaction between cigarette smoke and tamoxifen in rats a UPLC-MS/MS method for the simultaneous determination of NNAL and tamoxifen along with its metabolites in rat plasma has been developed and validated. Analytes were extracted with methanol and separated on a HSS T3 column by a gradient elution with the mobile phase consisting of acetonitrile and water. The lower limits of quantitation ranged from 0.05 to 0.62 ng/mL. Precisions showed RSD <15.8% and accuracy in the range 80.6-116.0%. Mean analyte recoveries ranged from 76.9 to 108.4%. The method was successfully applied to study the effects of cigarette smoke condensate (CSC), NNK and benzo(a)pyrene pre-treatment on the pharmacokinetics of tamoxifen and its metabolites in rats. Significant effects of CSC, NNK, benzo(a)pyrene were observed on pharmacokinetics of tamoxifen and its metabolites. We also found that plasma NNAL levels are statistically significant correlated with plasma 4-hydroxy-tamoxifen and endoxifen.

Prospective evaluation of luteal phase length and natural fertility

OBJECTIVE

To evaluate the impact of a short luteal phase on fecundity.

DESIGN

Prospective time-to-pregnancy cohort study.

SETTING

Not applicable.

PATIENT(S)

Women trying to conceive, ages 30-44 years, without known infertility.

INTERVENTION(S)

Daily diaries, ovulation prediction testing, standardized pregnancy testing.

MAIN OUTCOME MEASURE(S)

Subsequent cycle fecundity.

RESULT(S)

Included in the analysis were 1,635 cycles from 284 women. A short luteal phase (≤11 days including the day of ovulation) occurred in 18% of observed cycles. Mean luteal phase length was 14 days. Significantly more women with a short luteal phase were smokers. After adjustment for age, women with a short luteal phase had 0.82 times the odds of pregnancy in the subsequent cycle immediately following the short luteal phase compared with women without a short luteal phase. Women with a short luteal length in the first observed cycle had significantly lower fertility after the first 6 months of pregnancy attempt, but at 12 months there was no significant difference in cumulative probability of pregnancy.

CONCLUSION(S)

Although an isolated cycle with a short luteal phase may negatively affect short-term fertility, incidence of infertility at 12 months was not significantly higher among these women.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01028365.

Cigarette smoking behaviour and blood metabolomics

BACKGROUND

Identifying circulating metabolites related to cigarette smoking may provide insight into the biological mechanisms of smoking-related diseases and the nature of addiction. However, previous studies are limited, generally small, and have largely targeted a priori metabolites.

METHODS

We examined associations between cigarette smoking and metabolites using an untargeted metabolomics approach in 892 men and women from four studies including participants from Italy, USA, China and Finland. We examined associations between individual log-transformed metabolites and two key smoking phenotypes (current smoking status and cigarettes per day [cig/day]) using linear regression. Fixed-effect meta-analysis was used to combine results across studies. Strict Bonferroni thresholds were used as our significance criteria. We further examined associated metabolites with other metrics of smoking behaviuor (current versus former, former versus never, smoking duration and years since quitting) in the US study.

RESULTS

We identified a total of 25 metabolites associated with smoking behaviours; 24 were associated with current smoking status and eight with cig/day. In addition to three well-established nicotine metabolites (cotinine, hydroxycotinine, cotinine N-oxide), we found an additional 12 xenobiotic metabolites involved in benzoatic (e.g. 3-ethylphenylsulphate) or xanthine metabolism (e.g. 1-methylurate), three amino acids (o-cresol sulphate, serotonin, indolepropionate), two lipids (scyllo-inositol, pregnenolone sulphate), four vitamins or cofactors [e.g. bilirubin (Z,Z)], and one carbohydrate (oxalate).

CONCLUSIONS

We identified associations between cigarette smoking and a diverse range of metabolites. Our findings, with further validation in future studies, have implications regarding aetiology and study design of smoking-related diseases.

Alcohol Consumption and Urinary Estrogens and Estrogen Metabolites in Premenopausal Women

In a cross-sectional analysis, we evaluated the associations of usual total alcohol and wine intake with a comprehensive profile of mid-luteal phase urinary estrogens and estrogen metabolites (referred to jointly as EM) in a sample of 603 premenopausal women participating in the Nurses' Health Study II (NHSII). A total of 15 individual EM (pmol/mg creatinine) were measured by a liquid chromatography/tandem mass spectrometry (LC-MS/MS) method with high accuracy and reproducibility. We used linear mixed models to calculate the adjusted geometric means of individual EM, EM grouped by metabolic pathways, and pathway ratios by category of alcohol intake with non-drinkers of alcohol as the referent. Total alcohol intake was not associated with total EM but was positively associated with estradiol (26% higher among women consuming >15 g/day vs. non-drinkers; P trend = 0.03). Wine consumption was positively associated with a number of EM measures including estradiol (22% higher among women consuming ≥ 5 drinks/week vs. non-drinkers, P trend < 0.0001). In conclusion, the total alcohol intake was positively and significantly associated with urinary estradiol levels. Some differences in urinary estrogen metabolites were observed with wine drinking, when compared with non-drinkers. This study strengthens the evidence that alcohol consumption might play a role in breast cancer and other estrogen-related conditions. Additional studies of premenopausal women are needed to further explore the association of alcohol, particularly the specific types of alcohol, on patterns of estrogen metabolism in blood, urine, and tissue.

Systematic and meta-analytic review of research examining the impact of menstrual cycle phase and ovarian hormones on smoking and cessation

INTRODUCTION

To determine the effect of ovarian hormones on smoking, we conducted a systematic review of menstrual cycle effects on smoking (i.e., ad lib smoking, smoking topography, and subjective effects) and cessation-related behaviors (i.e., cessation, withdrawal, tonic craving, and cue-induced craving).

METHODS

Thirty-six papers were identified on MEDLINE that included a menstrual-related search term (e.g., menstrual cycle, ovarian hormones), a smoking-related search term (e.g., smoking, nicotine), and met all inclusion criteria. Thirty-two studies examined menstrual phase, 1 study measured hormone levels, and 3 studies administered progesterone.

RESULTS

Sufficient data were available to conduct meta-analyses for only 2 of the 7 variables: withdrawal and tonic craving. Women reported greater withdrawal during the luteal phase than during the follicular phase, and there was a nonsignificant trend for greater tonic craving in the luteal phase. Progesterone administration was associated with decreased positive and increased negative subjective effects of nicotine. Studies of menstrual phase effects on the other outcome variables were either small in number or yielded mixed outcomes.

CONCLUSIONS

The impact of menstrual cycle phase on smoking behavior and cessation is complicated, and insufficient research is available upon which to conduct meta-analyses on most smoking outcomes. Future progress will require collecting ovarian hormone levels to more precisely quantify the impact of dynamic changes in hormone levels through the cycle on smoking behavior. Clarifying the relationship between hormones and smoking-particularly related to quitting, relapse, and medication response-could determine the best type and timing of interventions to improve quit rates for women.

Dietary Fat and Fiber Intakes Are Not Associated with Patterns of Urinary Estrogen Metabolites in Premenopausal Women

BACKGROUND

Interindividual differences in the bioavailability of potentially carcinogenic estrogen and estrogen metabolites (EMs) may play a role in the risk of breast cancer.

OBJECTIVE

We examined whether dietary intakes of fiber and fat influence premenopausal EM profiles through effects on estrogen synthesis, metabolism, or excretion.

METHODS

We conducted a cross-sectional analysis of 598 premenopausal women who participated in a reproducibility study (n = 109) or served as controls in a nested case-control study of breast cancer (n = 489) within the Nurses' Health Study II. Dietary intakes of fiber and fat were assessed via semiquantitative food frequency questionnaires in 1995 and 1999. Midluteal urine samples were collected between 1996 and 1999 and EMs were quantified with the use of HPLC-tandem mass spectrometry. Linear mixed models were used to estimate creatinine-adjusted geometric means for individual EMs and their pathway groups across categories of dietary intake while controlling for total energy intake and potential confounders.

RESULTS

Higher total dietary fiber intake (>25 g/d vs. ≤15 g/d) was associated with significantly higher concentrations of 4-methoxyestradiol (50% difference, P-difference = 0.01, P-trend = 0.004) and lower concentrations of 17-epiestriol (-27% difference, P-difference = 0.03, P-trend = 0.03), but was not associated with any other EMs. The associations did not vary by fiber intake from different sources. Total fat intake (>35% energy vs. ≤25% energy) was suggestively positively associated with 17-epiestriol (22.6% difference, P-difference = 0.14, P-trend = 0.06); the association was significant for polyunsaturated fatty acid (37% difference, P-difference = 0.01, P-trend = 0.01) and trans fat (36.1% difference, P-difference = 0.01, P-trend = 0.01) intakes.

CONCLUSION

Fiber and fat intakes were not strongly associated with patterns of estrogen metabolism in premenopausal women. Our data suggest estrogen metabolism is not a major mechanism through which dietary fiber and fat may affect breast or other hormone-related cancer risks.

Caffeine, coffee, and tea intake and urinary estrogens and estrogen metabolites in premenopausal women

BACKGROUND

Prior studies have found weak inverse associations between breast cancer and caffeine and coffee intake, possibly mediated through their effects on sex hormones.

METHODS

High-performance liquid chromatography/tandem mass spectrometry was used to quantify levels of 15 individual estrogens and estrogen metabolites (EM) among 587 premenopausal women in the Nurses' Health Study II with mid-luteal phase urine samples and caffeine, coffee, and/or tea intakes from self-reported food frequency questionnaires. Multivariate linear mixed models were used to estimate geometric means of individual EM, pathways, and ratios by intake categories, and P values for tests of linear trend.

RESULTS

Compared with women in the lowest quartile of caffeine consumption, those in the top quartile had higher urinary concentrations of 16α-hydroxyestrone (28% difference; Ptrend = 0.01) and 16-epiestriol (13% difference; Ptrend = 0.04), and a decreased parent estrogens/2-, 4-, 16-pathway ratio (Ptrend = 0.03). Coffee intake was associated with higher 2-catechols, including 2-hydroxyestradiol (57% difference, ≥4 cups/day vs. ≤6 cups/week; Ptrend = 0.001) and 2-hydroxyestrone (52% difference; Ptrend = 0.001), and several ratio measures. Decaffeinated coffee was not associated with 2-pathway metabolism, but women in the highest (vs. lowest) category of intake (≥2 cups/day vs. ≤1-3 cups/month) had significantly lower levels of two 16-pathway metabolites, estriol (25% difference; Ptrend = 0.01) and 17-epiestriol (48% difference; Ptrend = 0.0004). Tea intake was positively associated with 17-epiestriol (52% difference; Ptrend = 0.01).

CONCLUSION

Caffeine and coffee intake were both associated with profiles of estrogen metabolism in premenopausal women.

IMPACT

Consumption of caffeine and coffee may alter patterns of premenopausal estrogen metabolism.

Association between the Adherence to the International Guidelines for Cancer Prevention and Mammographic Density

Introduction

Mammographic density (MD) is considered a strong predictor of Breast Cancer (BC). The objective of the present study is to explore the association between MD and the compliance with the World Cancer Research Fund and the American Institute for Cancer Research (WCRF/AICR) recommendations for cancer prevention.

Methods

Data of 3584 women attending screening from a population-based multicenter cross-sectional study (DDM-Spain) collected from October 7, 2007 through July 14, 2008, was used to calculate a score that measures the level of compliance with the WCRF/AICR recommendations: R1)Maintain adequate body weight; R2)Be physically active; 3R)Limit the intake of high density foods; R4)Eat mostly plant foods; R5)Limit the intake of animal foods; R6)Limit alcohol intake; R7)Limit salt and salt preserved food intake; R8)Meet nutritional needs through diet. The association between the score and MD (assessed by a single radiologist using a semi-quantitative scale) was evaluated using ordinal logistic models with random center-specific intercepts adjusted for the main determinants of MD. Stratified analyses by menopausal status and smoking status were also carried out.

Results

A higher compliance with the WCRF/AICR recommendations was associated with lower MD (OR_{1-unit increase} = 0.93 95%CI:0.86;0.99). The association was stronger in postmenopausal women (OR = 0.91 95%CI:0.84;0.99) and nonsmokers (OR = 0.87;95%CI:0.80;0.96 for nonsmokers, OR = 1.01 95%CI:0.91;1.12 for smokers, P-interaction = 0.042). Among nonsmokers, maintaining adequate body weight (OR = 0.81 95%CI:0.65;1.01), practicing physical activity (OR = 0.68 95%CI:0.48;0.96) and moderating the intake of high-density foods (OR = 0.58 95%CI:0.40;0.86) and alcoholic beverages (OR = 0.76 95%CI:0.55;1.05) were the recommendations showing the strongest associations with MD.

Conclusions

postmenopausal women and non-smokers with greater compliance with the WCRF/AICR guidelines have lower MD. These results may provide guidance to design specific recommendations for screening attendants with high MD and therefore at higher risk of developing BC.

Risk factors for endometrial cancer in black and white women: a pooled analysis from the Epidemiology of Endometrial Cancer Consortium (E2C2)

PURPOSE

Endometrial cancer (EC) is the most common gynecologic cancer in the USA. Over the last decade, the incidence rate has been increasing, with a larger increase among blacks. The aim of this study was to compare risk factors for EC in black and white women.

METHODS

Data from seven cohort and four case-control studies were pooled. Unconditional logistic regression was used to estimate adjusted odds ratios (OR) and 95 % confidence intervals for each risk factor in blacks and whites separately.

RESULTS

Data were pooled for 2,011 black women (516 cases and 1,495 controls) and 19,297 white women (5,693 cases and 13,604 controls). BMI ≥ 30 was associated with an approximate threefold increase in risk of EC in both black and white women (ORblack 2.93, 95 % CI 2.11, 4.07 and ORwhite 2.99, 95 % CI 2.74, 3.26). Diabetes was associated with a 30-40 % increase in risk among both groups. Increasing parity was associated with decreasing risk of EC in blacks and whites (p value = 0.02 and <0.001, respectively). Current and former smoking was associated with decreased risk of EC among all women. Both black and white women who used oral contraceptives for 10 +years were also at reduced risk of EC (OR 0.49, 95 % CI 0.27, 0.88 and OR 0.69, 95 % CI 0.58, 0.83, respectively). Previous history of hypertension was not associated with EC risk in either group.

CONCLUSIONS

The major known risk factors for EC exert similar effects on black and white women. Differences in the incidence rates between the two populations may be due to differences in the prevalence of risk factors.

The ratio of the estradiol metabolites 2-hydroxyestrone (2-OHE1) and 16α-hydroxyestrone (16-OHE1) may predict breast cancer risk in postmenopausal but not in premenopausal women: two case-control studies

PURPOSE

Two main estradiol metabolites have different biological behavior with tumorigenic features of 16-OHE1 and antiproliferative characteristics of 2-OHE1. We investigated the ratio of these estradiol metabolites in pre- and postmenopausal patients with breast cancer (BC) within two case-control studies.

METHODS

From 41 premenopausal patients with (cases) and without (controls N = 211) BC and 207 postmenopausal patients with and without BC (N = 206), urine samples were collected. Urine samples were collected prior to surgery and stored at -20 °C until measurement by ELISA. The multiple linear regression test with two interactions was performed to evaluate the influence of different factors on the metabolic ratio.

RESULTS

In premenopausal patients, log ratio of 2-OHE1/16-OHE1 was 0.25 (CI 0.20;0.29) and 0.21 (CI 0.11;0.31) for controls and cases without significant difference. In postmenopausal patients, log ratio was 0.22 (CI 0.17;0.26) and 0.11 (CI 0.07;0.15) in controls and cases, respectively, and was statistically significantly lower (p = 0.0002). Log ratio was significantly influenced by BMI, but only in postmenopausal patients, an increased BMI resulted in a significantly (p < 0.042) decreased ratio.

CONCLUSIONS

Our case control studies suggest that in postmenopausal women a different metabolism of estrogens may play a role in the tumorigenesis of breast cancer. This genetically determined metabolism could be influenced by the exogenic factor BMI. In premenopausal women different hormone levels at different time points of the menstrual cycle may be an explanation that why we could not find an influence of estrogen metabolism.

Terminal duct lobular unit involution of the normal breast: implications for breast cancer etiology

BACKGROUND

Greater degrees of terminal duct lobular unit (TDLU) involution have been linked to lower breast cancer risk; however, factors that influence this process are poorly characterized.

METHODS

To study this question, we developed three reproducible measures that are inversely associated with TDLU involution: TDLU counts, median TDLU span, and median acini counts/TDLU. We determined factors associated with TDLU involution using normal breast tissues from 1938 participants (1369 premenopausal and 569 postmenopausal) ages 18 to 75 years in the Susan G. Komen Tissue Bank at the Indiana University Simon Cancer Center. Multivariable zero-inflated Poisson models were used to estimate relative risks (RRs) and 95% confidence intervals (95% CIs) for factors associated with TDLU counts, and multivariable ordinal logistic regression models were used to estimate odds ratios (ORs) and 95% CIs for factors associated with categories of median TDLU span and acini counts/TDLU.

RESULTS

All TDLU measures started declining in the third age decade (all measures, two-sided P trend ≤ .001); and all metrics were statistically significantly lower among postmenopausal women. Nulliparous women demonstrated lower TDLU counts compared with uniparous women (among premenopausal women, RR = 0.79, 95% CI = 0.73 to 0.85; among postmenopausal, RR = 0.67, 95% CI = 0.56 to 0.79); however, rates of age-related TDLU decline were faster among parous women. Other factors were related to specific measures of TDLU involution.

CONCLUSION

Morphometric analysis of TDLU involution warrants further evaluation to understand the pathogenesis of breast cancer and assessing its role as a progression marker for women with benign biopsies or as an intermediate endpoint in prevention studies.

Impact of smoking on estrogenic efficacy

Depending on the type, duration and intensity of cigarette smoking, the efficacy of endogenous and exogenous estrogen can be reduced or completely cancelled. Not only does smoking diminish the beneficial effects of estrogen on hot flushes and urogenital symptoms and its positive effects on lipid metabolism, but smoking also can reduce estrogen's ability to prevent osteoporosis and perhaps also cardiovascular diseases. This is mainly caused by dose-dependent elevated hepatic clearance, partially in conjunction with lower estrogen levels, and has been demonstrated so far only with oral estrogen applications. Compensation for the failure of therapeutic action should not be made by increasing the dose in smokers since this might result in the production of potentially mutagenic estrogen metabolites associated with a higher risk of breast cancer. Since the favorable effects of estrogens seem to be not lost in smokers when estrogens are applied transdermally, this route should be preferred in smokers. The most important conclusion from the data presented is that the effects of smoking are very complex and dependent on a multiplicity of factors, so that different types of clinically relevant negative effects must be expected. Women who continue to smoke despite all warnings should be informed that smoking, in addition to all its other negative effects, can also jeopardize the success of hormone replacement therapy.

Women and Smoking: The Effect of Gender on the Epidemiology, Health Effects, and Cessation of Smoking

Smoking is still the leading cause of premature morbidity and mortality. This paper examines new research on gender differences and the epidemiology of smoking, smoking-related morbidity and mortality, and factors that affect smoking cessation. The rate of decline in the prevalence of smoking has been slowing, especially among adolescent girls. New research suggests that, compared with men, women may be more susceptible to smoking-related morbidity and mortality. Gender-related barriers to smoking cessation include weight gain, sex hormones, and mood. Furthermore, the sensory aspects of smoking may have more of an effect on smoking treatment for women than for men. We discuss new studies that examine smoking-cessation interventions that may be particularly beneficial for women, including exercise (as an adjunct intervention), very low nicotine content cigarettes, and a variety of pharmacotherapy. Further research is needed to identify and target the gender-specific needs of smokers.