Cigarette smoking and urinary oestrogen excretion in premenopausal and post-menopausal women

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.

Women and COPD: do we need more evidence?

The increasingly female face of chronic obstructive pulmonary disease (COPD) prevalence among women has equalled that of men since 2008, due in part to increased tobacco use among women worldwide and exposure to biomass fuels. This finding is supported by a number of characteristics. There is evidence of susceptibility to smoking and other airborne contaminants, along with epidemiological and phenotypic manifestations. COPD has thus become the leading cause of death in women in the USA. The clinical presentation is characterised by increasingly pronounced dyspnoea with a marked tendency towards anxiety and depression, undernutrition, nonsmall cell lung cancer (especially adenocarcinoma) and osteoporosis. Quality of life is also more significantly impacted. The theories advanced to explain these differences involve the role played by oestrogens, impaired gas exchange in the lungs and smoking habits. While these differences require appropriate therapeutic responses (smoking cessation, pulmonary rehabilitation, long-term oxygen therapy), barriers to the treatment of women with COPD include greater under-diagnosis than in men, fewer spirometry tests and medical consultations. Faced with this serious public health problem, we need to update and adapt our knowledge to the epidemiological changes.

The face of COPD is increasingly female. We need more evidence and a change in how the disease is managed. http://ow.ly/zueL30mWqlS

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.

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.

Epidemiology of Endometrial Carcinoma: Etiologic Importance of Hormonal and Metabolic Influences

Endometrial carcinoma is the most common gynecologic cancer in developed nations, and the annual incidence is projected to increase, secondary to the high prevalence of obesity, a strong endometrial carcinoma risk factor. Although endometrial carcinomas are etiologically, biologically, and clinically diverse, hormonal and metabolic mechanisms are particularly strongly implicated in the pathogenesis of endometrioid carcinoma, the numerically predominant subtype. The centrality of hormonal and metabolic disturbances in the pathogenesis of endometrial carcinoma, combined with its slow development from well-characterized precursors in most cases, offers a substantial opportunity to reduce endometrial carcinoma mortality through early detection, lifestyle modification, and chemoprevention. In this chapter, we review the epidemiology of endometrial carcinoma, emphasizing theories that link risk factors for these tumors to hormonal and metabolic mechanisms. Future translational research opportunities related to prevention are discussed.

Cigarette smoking and endometrial carcinoma risk: the role of effect modification and tumor heterogeneity

PURPOSE

The inverse relationship between cigarette smoking and endometrial carcinoma risk is well established. We examined effect modification of this relationship and associations with tumor characteristics in the National Institutes of Health-AARP Diet and Health Study.

METHODS

We examined the association between cigarette smoking and endometrial carcinoma risk among 110,304 women. During 1,029,041 person years of follow-up, we identified 1,476 incident endometrial carcinoma cases. Multivariable Cox proportional hazards regression models were used to estimate relative risks (RRs) and 95 % confidence intervals (CIs) for the association between smoking status, years since smoking cessation, and endometrial carcinoma risk overall and within strata of endometrial carcinoma risk factors. Effect modification was assessed using likelihood ratio test statistics. Smoking associations by histologic subtype/grade and stage at diagnosis were also evaluated.

RESULTS

Reduced endometrial carcinoma risk was evident among former (RR 0.89, 95 % CI 0.80, 1.00) and current (RR 0.65, 95 % CI 0.55, 0.78) smokers compared with never smokers. Smoking cessation 1-4 years prior to baseline was significantly associated with endometrial carcinoma risk (RR 0.65, 95 % CI 0.48, 0.89), while cessation ≥ 10 years before baseline was not. The association between smoking and endometrial carcinoma risk was not significantly modified by any endometrial carcinoma risk factor, nor did we observe major differences in risk associations by tumor characteristics.

CONCLUSION

The cigarette smoking-endometrial carcinoma risk relationship was consistent within strata of important endometrial carcinoma risk factors and by clinically relevant tumor characteristics.

Lack of an association between passive smoking and incidence of female breast cancer in non-smokers: evidence from 10 prospective cohort studies

BACKGROUND

Several case-control studies have suggested that passive smoking may increase the incidence of female breast cancer. However, the results of cohort studies have been inconsistent in establishing an association. The present study evaluated the association between passive smoking and incidence of female breast cancer through a meta-analysis of prospective cohort studies.

METHODS

Relevant articles published before August 2012 were identified by searching the electronic databases PubMed, Embase, and Web of Science. Pooled relative risks (RRs) were determined with either a fixed or random effects model and were used to assess the strength of the association. Sensitivity and subgroup analyses according to ethnicity, menopausal status, and the period and place of exposure to passive smoking were also performed.

RESULTS

Ten prospective cohort studies involving 782 534 female non-smokers were included in the meta-analysis and 14 831 breast cancer cases were detected. Compared with the women without exposure to passive smoking, the overall combined RR of breast cancer was 1.01 (95% confidence interval: 0.96 to 1.06, P = 0.73) among women with exposure to passive smoking. Similar results were achieved through the subgroup analyses. No evidence of publication bias was observed.

CONCLUSION

The results suggest that passive smoking may not be associated with increased incidence of breast cancer. However, the present conclusion should be considered carefully and confirmed with further studies.

Estrogen replacement therapy and asthma

A growing body of clinical and experimental evidence indicates that female sex hormones, particularly estrogen, have significant effects on normal airway function as well as on respiratory disorders, such as asthma. These effects are very complex and are exerted at several levels, directly on airway reactivity or indirectly through regulation of the immune and inflammatory responses in the lung. They can have relevant clinical implications not only according to the phases of the reproductive life in women, but also in relation to the therapeutical administration of estrogen, as in the case of menopausal hormone therapy. Clinical evidence suggests that administration of estrogen to menopausal women is associated with increased rates of newly diagnosed asthma. Conversely, functional studies show that estrogen can improve objective indexes of respiratory functionality.

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

BACKGROUND

Smoking has been hypothesized to decrease biosynthesis of parent estrogens (estradiol and estrone) and increase their metabolism by 2-hydroxylation. However, comprehensive studies of smoking and estrogen metabolism by 2-, 4-, or 16-hydroxylation are sparse.

METHODS

Fifteen urinary estrogens and estrogen metabolites (jointly called EM) were measured by liquid chromatography/tandem mass spectrometry (LC/MS-MS) in luteal phase urine samples collected during 1996 to 1999 from 603 premenopausal women in the Nurses' Health Study II (NHSII; 35 current, 140 former, and 428 never smokers). We calculated geometric means and percentage differences of individual EM (pmol/mg creatinine), metabolic pathway groups, and pathway ratios, by smoking status and cigarettes per day (CPD).

RESULTS

Total EM and parent estrogens were nonsignificantly lower in current compared with never smokers, with estradiol significant (P(multivariate) = 0.02). We observed nonsignificantly lower 16-pathway EM (P = 0.08) and higher 4-pathway EM (P = 0.25) and similar 2-pathway EM in current versus never smokers. EM measures among former smokers were similar to never smokers. Increasing CPD was significantly associated with lower 16-pathway EM (P-trend = 0.04) and higher 4-pathway EM (P-trend = 0.05). Increasing CPD was significantly positively associated with the ratios of 2- and 4-pathway to parent estrogens (P-trend = 0.01 and 0.002), 2- and 4-pathway to 16-pathway (P-trend = 0.02 and 0.003), and catechols to methylated catechols (P-trend = 0.02).

CONCLUSIONS

As hypothesized, we observed lower urinary levels of total EM and parent estrogens in active smokers. Our results also suggest smoking is associated with altered estrogen metabolism, specifically increased 2- and 4-hydroxylation, decreased 16-hydroxylation, and decreased catechol methylation.

IMPACT

Our study suggests how smoking might influence estrogen-related cancers and conditions.

Asthma and the menopause: a systematic review and meta-analysis

OBJECTIVE

To review the available literature to determine whether the menopausal transition is associated with asthma incidence.

METHODS

We performed a systematic review and meta-analysis of cohort and cross-sectional studies providing a definition/assessment of menopausal status, incidence or prevalence of a defined diagnosis of asthma, and providing a measure of the association or of menopausal state and asthma or enough data for a calculation of this association. Where possible these meta-analytic estimates were also stratified by intake of menopausal hormone therapy (MHT).

RESULTS

Of 76 potentially relevant articles, 8 studies met the inclusion criteria and were included in the review, and 6 in the meta-analysis. There was heterogeneity across studies: four studies reported slightly increased prevalence rates of asthma in post-menopause, one large cohort yielded a lower asthma incidence and one cross-sectional study a lower prevalence in post-menopause. Overall, the meta-analysis showed no significant association between menopause and asthma rates. When stratifying by use of MHT, the association between menopause and asthma rates was increased in women reporting use of MHT (RR 1.32, 95%CI 1.01-1.74), but not in women not using MHT.

CONCLUSION

We found no significant association of menopause with asthma prevalence or incidence except for women reporting use of MHT. However, these findings result from a small number of studies, including only 1 large cohort with incidence rates for pre- as well as post-menopause. Further studies are needed addressing more closely subgroup analyses and a possible modification of the association of menopause and asthma by MHT.

Postmenopausal hormone therapy and asthma onset in the E3N cohort

BACKGROUND

Epidemiological studies have suggested that female hormones might play a role in asthma and that menopausal hormone therapy (MHT or hormone replacement therapy (HRT)) might increase the risk of asthma in postmenopausal women. The only prospective study addressing this issue reports an increase in the risk of developing asthma which was similar for oestrogen alone and oestrogen/progestagen treatment.

METHODS

The association between the use of different types of MHT and the risk of asthma onset in postmenopausal women was investigated prospectively from 1990 to 2002 by biennial questionnaires as part of the French E3N cohort study. Asthma onset was considered to be the time of medical diagnosis of asthma cases occurring during the follow-up of women who were asthma free at baseline. Cox proportional hazards models were used, adjusting for potential confounding factors.

RESULTS

Among 57 664 women free of asthma at menopause, 569 incident cases of asthma were identified during 495 448 years of follow-up. MHT was related to an increased risk of asthma onset (HR=1.20, 95% CI 0.98 to 1.46) among recent users. The increase in risk of asthma onset was only significant among women reporting the use of oestrogen alone (HR=1.54, 95% CI 1.13 to 2.09) particularly in never smokers (HR=1.80, 95% CI 1.15 to 2.80) and women reporting allergic disease prior to asthma onset (HR=1.86, 95% CI 1.18 to 2.93). A small increase in the risk of asthma onset associated with the use of oestrogen/progestagen was also observed in these subgroups.

CONCLUSION

Postmenopausal use of oestrogen alone was associated with an increased rate of newly diagnosed asthma in menopausal women.

Mutagen sensitivity, tobacco smoking and breast cancer risk: a case-control study

Given the high incidence of breast cancer and that more than half of cases remain unexplained, the need to identify risk factors for breast cancer remains. Deficiencies in DNA repair capacity have been associated with cancer risk. The mutagen sensitivity assay (MSA), a phenotypic marker of DNA damage response and repair capacity, has been consistently shown to associate with the risk of tobacco-related cancers.

METHODS

In a case-control study of 164 women with breast cancer and 165 women without the disease, we investigated the association between mutagen sensitivity and risk of breast cancer using bleomycin as the mutagen.

RESULTS

High bleomycin sensitivity (>0.65 breaks per cell) was associated with an increased risk of breast cancer, with an adjusted odds ratio of 2.8 [95% confidence interval (CI) = 1.7-4.5]. Risk increased with greater number of bleomycin-induced chromosomal breaks (P(trend) = 0.01). The association between bleomycin sensitivity and breast cancer risk was greater for women who were black, premenopausal and ever smokers. Our data also suggest that bleomycin sensitivity may modulate the effect of tobacco smoking on breast cancer risk. Among women with hypersensitivity to bleomycin, ever smokers had a 1.6-fold increased risk of breast cancer (95% CI = 0.6-3.9, P for interaction between tobacco smoking and bleomycin sensitivity = 0.32).

CONCLUSIONS

Increased bleomycin sensitivity is significantly associated with an increased risk of breast cancer in both pre- and postmenopausal women. Our observation that the effect of tobacco smoking on breast cancer risk may differ based on mutagen sensitivity status warrants further investigation.

Cigarette Smoking,STAT4andTNFRSF1BPolymorphisms, and Systemic Lupus Erythematosus in a Japanese Population

Objective.

Recent studies have identified signal transducer and activator of transcription 4 (STAT4) as a susceptibility gene for systemic lupus erythematosus (SLE) in different populations. Similarly, tumor necrosis factor receptor superfamily, member 1B (TNFRSF1B) has been reported to be associated with SLE risk in Japanese populations. Along with environmental factors such as smoking, both polymorphisms may modulate an individual’s susceptibility to SLE. We investigated these relationships in a case-control study to evaluate risk factors for SLE among Japanese women.

Methods.

We investigated the relationship of theSTAT4rs7574865 andTNFRSF1Brs1061622 polymorphisms to SLE risk with special reference to their combination and interaction with cigarette smoking among 152 SLE cases and 427 controls.

Results.

The TT genotype ofSTAT4rs7574865 was significantly associated with increased risk of SLE (OR 2.21, 95% CI 1.10–4.68). Subjects with at least one G allele ofTNFRSF1Brs1061622 had an increased risk of SLE (OR 1.56, 95% CI 0.99–2.47). The attributable proportion due to the interaction between theTNFRSF1Brs1061622 genotypes and smoking was estimated to be 0.49 (95% CI 0.07–0.92), indicating that 49% of the excess risk for SLE in smokers with at least one G allele was due to an additive interaction. A lack of significant associations ofSTAT4with smoking was observed. No significant gene-gene interactions were found among polymorphisms ofSTAT4andTNFRSF1B.

Conclusion.

Our findings suggest that the association between cigarette smoking and SLE could be differentiated by theTNFRSF1Brs1061622 T allele among female Japanese subjects. This preliminary exploratory result should be confirmed in a larger study.

Cigarette smoking, N-acetyltransferase 2 polymorphisms and systemic lupus erythematosus in a Japanese population

Cigarette smoking may be associated with an increased risk of systemic lupus erythematosus (SLE), but the underlying mechanism of this association remains unclear. N-acetyltransferase 2 (NAT2) is highly variable and detoxifies aromatic amines, an important class of carcinogens in tobacco smoke. Individuals who possess homozygous polymorphic alleles have a slower rate of metabolic detoxification of aromatic amines. We investigated the relationship of the NAT2 polymorphism to the risk of SLE with special reference to the interaction with cigarette smoking among 152 SLE cases and 427 controls in a female Japanese population. NAT2*4, NAT2*5B, NAT2*6A and NAT2*7B alleles were detected with polymerase chain reaction–restriction fragment length polymorphism. Individuals carrying the *4/*4 genotype are rapid acetylators, whereas those with homozygous non-*4 genotypes have a slow acetylator phenotype. Cigarette smoking was associated with an increased risk of SLE (odds ratio [OR] = 2.26; 95% confidence interval [CI] = 1.46–3.50). The slow acetylator genotype of NAT2 was significantly associated with an increased risk of SLE (OR = 2.34, 95% CI = 1.21–4.52) compared with the rapid acetylator genotype. A gene-environment interaction was suggested, with a combination of the NAT2 slow acetylator genotype and smoking conferring significantly higher risk (OR = 6.44, 95% CI = 3.07–13.52; attributable proportion due to interaction = 0.50, 95% CI = 0.12–0.88), compared with the NAT2 rapid acetylator genotype and no history of smoking. This study suggests that, in this Japanese population, the NAT2 slow acetylator status may be a determinant in susceptibility to SLE.

The influence of the environment and other exogenous agents on spontaneous abortion risk

It is estimated that close to 30% of all pregnancies end in spontaneous abortion. Although about 60% of spontaneous abortions are thought to be due to genetic, infectious, hormonal, and immunological factors, the role of the environment remains poorly understood. Pregnancy involves a delicate balance of hormonal and immunological functions, which may be affected by environmental substances. Many toxic substances that are persistent in the environment and accumulate in the fatty tissues may disrupt this equilibrium. This overview addresses known risk factors for spontaneous abortions and examines the role, if any, that environmental factors (chemical and physical) may play in the etiology of this adverse health outcome.

Alcohol consumption and endometrial cancer risk: the multiethnic cohort

The role of alcohol intake in the etiology of endometrial cancer is unclear. We examined the impact of alcohol intake on endometrial cancer risk among 41,574 postmenopausal African-American, Japanese-American, Latina, Native-Hawaiian and White women recruited to the prospective Multiethnic Cohort Study in 1993-1996. During an average of 8.3 years of follow-up, 324 incident invasive endometrial cancer cases were identified among these women. Data on alcohol intake and endometrial cancer risk factors were obtained from the baseline questionnaire. Relative risks (RRs) and 95% confidence intervals (CIs) for endometrial cancer associated with alcohol intake were estimated using log-linear (Cox) proportional hazard models stratified by age, year of recruitment, ethnicity and study center, and adjusted for several confounding factors. Increased alcohol consumption was associated with increased risk (p trend = 0.013). Compared to nondrinkers, women consuming >or=2 drinks/day had a multivariate RR of 2.01 (95% CI: 1.30, 3.11). There was no increase in risk associated with <1 drink/day (RR = 1.01; 95% CI: 0.77, 1.33) and 1 to <2 drinks/day (RR = 1.09; 95% CI: 0.62, 1.93). There was no clear effect modification by body mass index, postmenopausal hormone use, parity, oral contraceptive use or smoking status, though our power to detect such interactions was limited. Our results suggest that only alcohol consumption equivalent to 2 or more drinks per day increases risk of endometrial cancer in postmenopausal women.

Lung function, respiratory symptoms, and the menopausal transition

BACKGROUND

There is limited information on potential changes in respiratory health when women enter the menopausal transition.

OBJECTIVE

We sought to investigate whether the menopausal transition is related to lung function and asthma and whether body mass index (BMI) modifies associations.

METHODS

Four thousand two hundred fifty-nine women from 21 centers (ECRHS II, 2002) responded to a questionnaire concerning women's health. Women aged 45 to 56 years not using exogenous sex hormones (n = 1274) were included in the present analysis. Lung function measurements (n = 1120) and serum markers of hormonal status (follicle-stimulating hormone, luteinizing hormone, and estradiol; n = 710) were available. Logistic and linear regression analyses were adjusted for BMI, age, years of education, smoking status, center, and height.

RESULTS

Women not menstruating for the last 6 months (n = 432, 34%) had significantly lower FEV(1) values (-120 mL [95% CI, -177 to -63]), lower forced vital capacity values (-115 mL [95% CI, -181 to -50]), and more respiratory symptoms (odds ratio [OR], 1.82 [95% CI, 1.27-2.61]) than those menstruating regularly. Results were similar when restricting analyses to those who never smoked. Associations were significantly stronger in women with BMIs of less than 23 kg/m(2) (respiratory symptoms: OR, 4.07 [95% CI, 1.88-8.80]; FEV(1) adjusted difference: -166 [95% CI, -263 to -70]) than in women with BMIs of 23 to 28 kg/m(2) (respiratory symptoms: OR, 1.10 [95% CI, 0.61-1.97], P(interaction): .04; FEV(1) adjusted difference, -54 [95% CI, -151 to 43], P(interaction) = .06).

CONCLUSIONS

Menopause is associated with lower lung function and more respiratory symptoms, especially among lean women.

Nucleotide excision repair genotype and the incidence of endometrial cancer: effect of other risk factors on the association

OBJECTIVES

Certain nucleotide excision repair (NER) genotypes appear to be associated with an altered risk of endometrial cancer. These associations could be modified by characteristics and exposures that themselves influence risk of disease.

METHODS

We conducted a population-based case-control study in western Washington State to address the role of specific NER genotypes in conjunction with relevant exposures, such as postmenopausal hormone therapy, obesity, parity, oral contraceptive use, and cigarette smoking on risk of endometrial cancer. Case women (n=371), ages 50-69 years, were diagnosed with invasive endometrial cancer between 1994 and 1999. Control women (n=420), matched to cases on age and county of residence, were selected using random-digit dialing (ages 50-65) and random selection from HCFA data files (ages 66-69).

RESULTS

Risk of endometrial cancer was not associated with ERCC1, ERCC2 (XPD), ERCC4 (XPF), or ERCC5 (XPG) genotype. A reduced risk of endometrial cancer was observed with presence of the XPA g23a variant allele, but only among women with a history of oral contraceptive use (OR 0.47, 95% CI 0.32-0.69). A decreased risk associated with carriage of at least one variant allele for both XPC A499V and XPC K939Q was restricted to women with BMI<30 kg/m2 (OR 0.45, 95% CI 0.25-0.82). The size of the association between these genotypes and risk of endometrial cancer did not differ by postmenopausal hormone use, parity, or smoking.

CONCLUSIONS

Our study provides limited evidence for interactions between NER genotypes and DNA damage-causing exposures in the etiology of endometrial cancer. Subsequent studies are needed to confirm the observed associations.

Hormone replacement therapy, body mass index and asthma in perimenopausal women: a cross sectional survey

BACKGROUND

Hormone replacement therapy (HRT) and obesity both appear to increase the risk of asthma. A study was undertaken to investigate the association of HRT with asthma and hay fever in a population of perimenopausal women, focusing on a possible interaction with body mass index (BMI).

METHODS

A postal questionnaire was sent to population based samples in Denmark, Estonia, Iceland, Norway, and Sweden in 1999-2001, and 8588 women aged 25-54 years responded (77%). Pregnant women, women using oral contraceptives, and women <46 years were excluded. Analyses included 2206 women aged 46-54 years of which 884 were menopausal and 540 used HRT. Stratified analyses by BMI in tertiles were performed.

RESULTS

HRT was associated with an increased risk for asthma (OR 1.57 (95% CI 1.07 to 2.30)), wheeze (OR 1.60 (95% CI 1.22 to 2.10)), and hay fever (OR 1.48 (95% CI 1.15 to 1.90)). The associations with asthma and wheeze were significantly stronger among women with BMI in the lower tertile (asthma OR 2.41 (95% CI 1.21 to 4.77); wheeze OR 2.04 (95% CI 1.23 to 3.36)) than in heavier women (asthma: p(interaction) = 0.030; wheeze: p(interaction) = 0.042). Increasing BMI was associated with more asthma (OR 1.08 (95% CI 1.05 to 1.12) per kg/m2). This effect was only found in women not taking HRT (OR 1.10 (95% CI 1.05 to 1.14) per kg/m2); no such association was detected in HRT users (OR 1.00 (95% CI 0.92 to 1.08) per kg/m2) (p(interaction) = 0.046). Menopause was not significantly associated with asthma, wheeze, or hay fever.

CONCLUSIONS

In perimenopausal women there is an interaction between HRT and BMI in the effects on asthma. Lean women who were HRT users had as high a risk for asthma as overweight women not taking HRT. It is suggested that HRT and overweight increase the risk of asthma through partly common pathways.

Cigarette smoking and effects on hormone function in premenopausal women

Cigarette smoke contains compounds that are suspected to cause reproductive damage and possibly affect hormone activity; therefore, we examined hormone metabolite patterns in relation to validated smoking status. We previously conducted a prospective study of women of reproductive age (n = 403) recruited from a large health maintenance organization, who collected urine daily during an average of three to four menstrual cycles. Data on covariates and daily smoking habits were obtained from a baseline interview and daily diary, and smoking status was validated by cotinine assay. Urinary metabolite levels of estrogen and progesterone were measured daily throughout the cycles. For the present study, we measured urinary levels of the pituitary hormone follicle-stimulating hormone (FSH) in a subset of about 300 menstrual cycles, selected by smoking status, with the time of transition between two cycles being of primary interest. Compared with nonsmokers, moderate to heavy smokers (>/= 10 cigarettes/day) had baseline levels (e.g., early follicular phase) of both steroid metabolites that were 25-35% higher, and heavy smokers (>/= 20 cigarettes/day) had lower luteal-phase progesterone metabolite levels. The mean daily urinary FSH levels around the cycle transition were increased at least 30-35% with moderate smoking, even after adjustment. These patterns suggest that chemicals in tobacco smoke alter endocrine function, perhaps at the level of the ovary, which in turn effects release of the pituitary hormones. This endocrine disruption likely contributes to the reported associations of smoking with adverse reproductive outcomes, including menstrual dysfunction, infertility, and earlier menopause.

Smoking and the risk of endometrial cancer: results from the Nurses' Health Study

An inverse association between smoking and endometrial cancer has generally been observed, primarily among current smokers. To assess this association, we analyzed data from the prospective Nurses' Health Study. From 1976 to 2000, 702 cases of invasive endometrial cancer were identified during 1.8 million person-years of follow-up. Smoking status was assessed in 1976 and updated every 2 years. Cox proportional hazards models were used to calculate multivariate relative risks (RRs), controlling for endometrial cancer risk factors. Compared to never smokers, the multivariate RR of endometrial cancer was significantly lower among both current smokers (RR = 0.63; 95% CI = 0.50-0.79) and past smokers (RR = 0.73; 95% CI = 0.62-0.87). When additionally adjusting for body mass index (BMI), the RR for current smokers was attenuated (RR = 0.72; 95% CI = 0.57-0.90), but the RR for past smokers did not change. Risk was lower among women who smoked 35 or more cigarettes a day (RR = 0.60; 95% CI = 0.39-0.91) and among those who smoked for 40 or more years (RR = 0.63; 95% CI = 0.45-0.87). Tests for trend, which excluded never smokers, were not statistically significant for any of the smoking variables analyzed. These data indicate that both current and past smoking are associated with a lower risk of endometrial cancer. The findings provide insight into disease etiology and suggest that the influence of smoking on endometrial cancer risk occurs even in early adulthood, is long-lasting, and may not be attributed solely to short-term hormonal modulation.

Lung cancer in women

Lung cancer is one of the most important avoidable causes of death around the world, it is the most widespread carcinoma with a very poor prognosis, and is the leading cause of cancer death in both developed and developing countries. At present more men than women die each year from lung cancer, but in recent years a rapid increase in lung cancer mortality has been observed among women in developed countries, contrasting with a levelling off or decrease among men. The rising trend in female lung cancer mortality has been observed to parallel with the past and current prevalence of cigarette smoking among women in the United States and elsewhere. An important role of other factors acting either as independent risk factors or interacting with the effect of smoking has been suggested by some studies among women, among them genetic, biologic and hormonal factors, and probably some factors related to the environment and lifestyle. There is a controversy concerning the claim that women have a different susceptibility to tobacco carcinogens, which might or might not be greater than men do. Since tobacco is far and away the strongest epidemiological risk factor for the development of lung cancer, comprehensive smoking control efforts are the priority in the prevention of lung cancer among women.

SULT1A1 genotype, active and passive smoking, and breast cancer risk by age 50 years in a German case-control study

INTRODUCTION

Sulfotransferase 1A1 (encoded by SULT1A1) is involved in the metabolism of procarcinogens such as heterocyclic amines and polycyclic aromatic hydrocarbons, both of which are present in tobacco smoke. We recently reported a differential effect of N-acetyltransferase (NAT) 2 genotype on the association between active and passive smoking and breast cancer. Additional investigation of a common SULT1A1 genetic polymorphism associated with reduced enzyme activity and stability might therefore provide deeper insight into the modification of breast cancer susceptibility.

METHODS

We conducted a population-based case-control study in Germany. A total of 419 patients who had developed breast cancer by age 50 years and 884 age-matched control individuals, for whom risk factor information and detailed smoking history were available, were included in the analysis. Genotyping was performed using a fluorescence-based melting curve analysis method. Multivariate logistic regression analysis was used to estimate breast cancer risk associated with the SULT1A1 Arg213His polymorphism alone and in combination with NAT2 genotype in relation to smoking.

RESULTS

The overall risk for breast cancer in women who were carriers of at least one SULT1A1*2 allele was not significantly different from that for women with the SULT1A1*1/*1 genotype (adjusted odds ratio 0.83, 95% confidence interval 0.66-1.06). Risk for breast cancer with respect to several smoking variables did not differ substantially between carriers of the *2 allele and noncarriers. However, among NAT2 fast acetylators, the odds ratio associated with passive smoking only (3.23, 95% confidence interval 1.05-9.92) was elevated in homozygous carriers of the SULT1A1*1 allele but not in carriers of the SULT1A1*2 allele (odds ratio 1.28, 95% confidence interval 0.50-3.31).

CONCLUSION

We found no evidence that the SULT1A1 genotype in itself modifies breast cancer risk associated with smoking in women up to age 50 years. In combination with NAT2 fast acetylator status, however, the SULT1A1*1/*1 genotype might increase breast cancer risk in women exposed to tobacco smoke.

Environmental tobacco smoke and breast cancer incidence

To evaluate whether environmental tobacco smoke (ETS) influences breast cancer incidence, data from a population-based case-control study were analyzed. Respondents with available ETS information assessed by in-person questionnaires included 1356 newly diagnosed cases and 1383 controls. Relative to nonsmokers who reported no residential ETS exposure throughout the life course, the odds ratios (OR) for breast cancer were not substantially elevated in relation to ETS exposure, active smoking, or a joint measure of active and passive smoking (OR, 1.15, 95% CI, 0.90, 1.48). An increased OR, however, was noted among nonsmokers who lived with a smoking spouse for over 27 years (2.10, 95% CI, 1.47, 3.02), although no dose-response was evident. Also, among women with hormone-receptor-positive tumors only, the OR for both active and passive smoking was increased (1.42 for ER+ PR+, 95% CI, 1.00, 2.00). Our data suggest that if there is an effect for ETS on breast cancer, that effect is restricted to selected subgroups of women, such as those with long-term exposure from a smoking spouse.

Tools for making correct decisions regarding hormone therapy. Part II. organ response and clinical applications

OBJECTIVE

To review existing scientific knowledge of the complicated and variable behavior and response to hormone therapy (HT) of different organs during aging, and to summarize long-term consequences on human health.

DESIGN

A MEDLINE computer search was performed to identify relevant articles.

RESULT(S)

Five body organs were evaluated. [1]. Physiologic aging of the bone has deleterious consequences on women's health and quality of life. Bone fractures could be attributed to the combination of estrogen depletion and osteoporosis, mechanisms of applied forces, and disturbed brain function, partially reversible by timely estrogen administration. [2]. Estrogen seems to have a profound neuroprotective effect. As physiologic aging of the brain is an unhealthy phenomenon, possible intervention is justified. The therapeutic time window seems crucial. [3]. The differentiation between response of a healthy or already damaged organ to sex hormones is the key factor to understanding the possible cardioprotective effects. [4]. Based on doubling time of tumor cells, intracrinology, epidemiological data on breast cancer, and behavior of breast cancer survivors in response to estrogen treatment, estrogen seems to be mainly a promoter and even a protector of breast cancer survivors. [5]. Colon cancer appears to be an estrogen-dependent tumor with a wide therapeutic window, as every report regardless of age and dose demonstrates protective effects.

CONCLUSION(S)

Knowledge of each organ's response to aging and sex hormone substitutions demonstrates that the organs could benefit from properly designed intervention. In the wake of the publication of the Women's Health Initiative study, which shocked the medical community, we suggest that the results be reevaluated according to the aforementioned principles, and that menopausal medicine could play an important role.

Cigarette smoking and the risk of systemic lupus erythematosus: a meta-analysis

OBJECTIVE

Existing studies present conflicting evidence for the role of cigarette smoking as a risk factor in the development of systemic lupus erythematosus (SLE). We performed an extensive search of the medical literature for all studies examining this relationship, and performed a meta-analysis to arrive at a more precise estimate of effect.

METHODS

We performed a computerized literature search for all studies (in all languages), using Medline and EMBASE (1966 to present) and the Cochrane Collaboration database, and completed hand searches of relevant bibliographies and abstracts of conference proceedings. Several investigators systematically extracted data from the relevant studies. Unpublished data were obtained from the author of one abstract. Studies were examined in aggregate for heterogeneity and publication bias. The relationships of current smoking and past smoking (prior to the onset of SLE) to development of SLE were analyzed separately.

RESULTS

Fifty-two studies were identified and chosen for detailed review. Of these, 9 (7 case-control and 2 cohort studies) were appropriate for inclusion in our meta-analyses. For current smokers compared with nonsmokers, the odds ratio (OR) for development of SLE was significantly elevated (OR 1.50, 95% confidence interval [95% CI] 1.09-2.08). Former smokers, compared with nonsmokers, did not demonstrate an increased risk of SLE (OR 0.98, 95% CI 0.75-1.27). Several subgroups were also analyzed.

CONCLUSION

Our meta-analysis of the 7 existing case-control and 2 cohort studies revealed a small but statistically significant association between current smoking and development of SLE. However, no association between past smoking and development of SLE was observed.

Cigarette smoking and the risk of endometrial cancer

Epidemiological studies have shown that cigarette smoking is associated with a reduced risk of endometrial cancer, in contrast to the increased risks observed with many other non-respiratory-tract cancers, including those of the bladder, pancreas, and cervix uteri. Some studies of endometrial cancer suggest that the inverse association with smoking is limited to certain groups of women, such as those who are postmenopausal or those taking hormone-replacement therapy. The biological mechanisms that might underlie this association remain unclear, although several have been proposed, including an antioestrogenic effect of cigarette smoking on circulating oestrogen concentrations, a reduction in relative bodyweight, and an earlier age at menopause. We have examined the evidence for an association between cigarette smoking and risk of endometrial cancer, including studies related to the proposed biological mechanisms.

Cigarette smoking and the risk of rheumatoid arthritis among postmenopausal women: results from the Iowa Women's Health Study

PURPOSE

To determine whether cigarette smoking increases the risk of rheumatoid arthritis among postmenopausal women.

SUBJECTS AND METHODS

We followed a cohort of 31 336 women in Iowa who were aged 55 to 69 years in 1986 and who had no history of rheumatoid arthritis. Through 1997, 158 cases of rheumatoid arthritis were identified and validated based on review of medical records and supplementary information provided by physicians. Multivariable Cox proportional hazards regression was used to derive rate ratios (RRs) and 95% confidence intervals (CIs) for the association between cigarette smoking and rheumatoid arthritis.

RESULTS

Compared with women who had never smoked, women who were current smokers (RR = 2.0; 95% CI: 1.3 to 2.9) or who had quit 10 years or less before study baseline (RR = 1.8; 95% CI: 1.1 to 3.1) were at increased risk of rheumatoid arthritis, but women who had quit more than 10 years before baseline were not at increased risk (RR = 0.9; 95% CI: 0.5 to 2.6). Both the duration and intensity of smoking were associated with rheumatoid arthritis. Multivariable adjustments for age, marital status, occupation, body mass index, age at menopause, oral contraceptive use, hormone replacement therapy, alcohol use, and coffee consumption did not alter these results.

CONCLUSION

These results suggest that abstinence from smoking may reduce the risk of rheumatoid arthritis among postmenopausal women.

Exogenous female sex steroid hormones and risk of asthma and asthma-like symptoms: a cross sectional study of the general population

BACKGROUND

Recent evidence suggests a role for hormonal factors in the aetiology of asthma.

METHODS

Data from a large study of women selected from the general population were used to relate treatment with oral hormonal contraceptives (OCP) and postmenopausal hormone replacement therapy (HRT) to the following asthma indicators: self-reported asthma, wheezing, cough at exertion, and use of medication for asthma. The study sample comprised 1536 premenopausal and 3016 postmenopausal women who participated in the third round of the Copenhagen City Heart Study in 1991–4. A total of 377 women were taking OCP (24.5% of premenopausal women) and 458 were on HRT (15.2% of postmenopausal women).

RESULTS

In premenopausal women 4.8% reported having asthma. The prevalence of self-reported asthma, wheeze, use of asthma medication, and cough at exertion was not significantly related to use of OCP. In postmenopausal women the prevalence of self-reported asthma was 6.2%. A weak but consistent association was observed between HRT and self-reported asthma (OR 1.42 (95% CI 0.95 to 2.12)), wheeze (OR 1.29 (95% CI 1.02 to 1.64)), cough at exertion (OR 1.34 (95% CI 1.01 to 1.77)), and use of asthma medication (OR 1.45 (95% CI 0.97 to 2.18)).

CONCLUSIONS

In this study of the general population no relationship was found between the use of OCP and asthma. Although an association was observed between HRT and asthma and asthma-like symptoms, this was relatively weak and it is concluded that there is no necessity to change present prescription practice.

Exogenous female sex steroid hormones and risk of asthma and asthma-like symptoms: a cross sectional study of the general population

BACKGROUND

Recent evidence suggests a role for hormonal factors in the aetiology of asthma.

METHODS

Data from a large study of women selected from the general population were used to relate treatment with oral hormonal contraceptives (OCP) and postmenopausal hormone replacement therapy (HRT) to the following asthma indicators: self-reported asthma, wheezing, cough at exertion, and use of medication for asthma. The study sample comprised 1536 premenopausal and 3016 postmenopausal women who participated in the third round of the Copenhagen City Heart Study in 1991-4. A total of 377 women were taking OCP (24.5% of premenopausal women) and 458 were on HRT (15.2% of postmenopausal women).

RESULTS

In premenopausal women 4.8% reported having asthma. The prevalence of self-reported asthma, wheeze, use of asthma medication, and cough at exertion was not significantly related to use of OCP. In postmenopausal women the prevalence of self-reported asthma was 6.2%. A weak but consistent association was observed between HRT and self-reported asthma (OR 1.42 (95% CI 0.95 to 2.12)), wheeze (OR 1.29 (95% CI 1.02 to 1.64)), cough at exertion (OR 1.34 (95% CI 1.01 to 1.77)), and use of asthma medication (OR 1.45 (95% CI 0.97 to 2.18)).

CONCLUSIONS

In this study of the general population no relationship was found between the use of OCP and asthma. Although an association was observed between HRT and asthma and asthma-like symptoms, this was relatively weak and it is concluded that there is no necessity to change present prescription practice.

Estimating steroid oestrogen inputs into activated sludge treatment works and observations on their removal from the effluent

A method to predict steroid oestrogen inputs into sewage works is described and tested against available data. For oestradiol (E2), 68% of the predictions were within 50% of the actual measured value, and for oestrone (E1), 52% of the estimations were within 50% of the measured value. Predictions for ethinyloestradiol (EE2), which are particularly sensitive to assumptions on the number of people taking the oral contraceptive, were less accurate. Five Italian and three Dutch activated sludge treatment works (STW) were sampled on two to three occasions for E2, E1, EE2 and E3 (E3 only in Italy) in both influent and effluent waters. High concentrations of E3 were found in the influent, as predicted, with a mean of 57 ng/1 and a mean of 10 ng/l in the effluent. Using the currently available data collected from composite samples, an average of 88% of E2 and 74% of E1 would appear to be removed by the activated sludge process.

Catecholestrogens excretion in smoking and non-smoking postmenopausal women receiving estrogen replacement therapy

Estrogens are involved in the etiology of breast cancer. Their blastomogenic influence may be partly realized through their conversion into catecholestrogens, rate of which may be modified by smoking. The risk of having breast cancer diagnosed can increase in women using estrogen replacement therapy (ERT). The principal aim of this investigation was to compare the excretion of classical estrogens and catecholestrogens in smoking and non-smoking postmenopausal women receiving Progynova (estradiol valerate, 2 mg/day, 1 month). Total 16 women were studied before and after treatment. Urinary estrogen profile method based on isotope dilution capillary gas chromatography-mass spectrometry was used. Before ERT, significantly lower excretion of 16-epiestriol and 4-hydroxyestrone (4-OHE1) and lower ratio of 4-OHE1/E1 were revealed in smokers. After ERT, much higher excretion of 2-OHE1, and 4-hydroxyestradiol (4-OHE2), higher ratios of 2-OHE1/E1 and 4-OHE1/E1 and lower ratio of 2-methoxyestrone/2-OHE1 were discovered in smokers as compared to non-smoking women. In conclusion only combination of ERT + smoking and not smoking itself leads to the specific prevalence of catecholestrogens (2-OH- and carcinogenic and DNA-damaging 4-OH-metabolites) that may increase risk of genotoxic variant of hormone-induced breast carcinogenesis without influence on the total morbidity.