Genetic polymorphisms, hormone levels, and hot flashes in midlife women

Functional variant rs10175368 which affects the expression of CYP1B1 plays a protective role against breast cancer in a Chinese Han population

OBJECTIVE

Cytochrome P450 1B1 ( CYP1B1 ) genetic variants are relevant in the pathogenesis of breast cancer. Exploring the relationships between CYP1B1 functional variants and breast cancer could improve our understanding of breast cancer molecular pathophysiology.

METHODS

This is a two-stage hospital-based case-control study of a Chinese Han population. Genotyping was performed to identify candidate gene variants. 3DSNP, ANNOVAR, and RegulomeDB were used to determine functional single nucleotide polymorphisms (SNPs). The relationship between candidate variants and breast cancer risk was evaluated through unconditional logistic regression analysis. The PancanQTL platform was used to perform cis and trans expression quantitative trait loci (eQTL) analysis of positive SNPs. The GSCA platform was then used to compare the gene expression levels of potential target genes between breast cancer tissue and normal tissue adjacent to the cancer.

RESULTS

rs10175368-T acted as a protective factor against breast cancer based on an additive model [odds ratio (OR) = 0.722, 95% confidence interval (CI) = 0.613-0.850; P < 0.001], and was identified as a protective factor in the postmenopausal population (OR = 0.601; 95% CI, 0.474-0.764; P < 0.001). eQTL analysis and analysis of differential expression in carcinoma and paracancerous tissues revealed that the expression level of CYP1B1 - AS1 was associated with rs10175368 and that CYP1B1-AS1 had significantly higher expression levels in breast cancer tissues than in paracancerous tissues.

CONCLUSION

We show, for the first time in a Chinese Han population, that the functional variant rs10175368 plays a protective role against breast cancer, especially in the postmenopausal population.

Alcohol Consumption Patterns and Risk of Early-Onset Vasomotor Symptoms in Premenopausal Women

The role of alcohol consumption in the risk of vasomotor symptoms (VMS), the most cardinal climacteric symptoms, is not well established. We examined their relationship with early-onset VMS among premenopausal women. Moderately-to-severely bothersome VMS, the primary outcome, was assessed using the Korean version of the Menopause-Specific Quality of Life questionnaire. The alcohol consumption categories included lifetime abstainer, former drinker, or current drinker, categorized as light, moderate, heavy, and very heavy. Compared with the lifetime-abstinence (reference), the multivariable-adjusted odds ratio (95% CIs) for prevalent VMS in alcohol consumption of <10, 10−19, 20−39, and ≥40 g/day were 1.42 (1.02−1.99), 1.99 (1.27−3.12), 2.06 (1.19−3.57), and 3.52 (1.72−7.20), respectively (p trend <0.01). Compared with the lifetime-abstinence, the multivariable-adjusted hazard ratios (95% CIs) for incident bothersome VMS among average alcohol consumption of <10, 10−19, 20−39, and ≥40 g/day were 1.10 (0.85−1.41), 1.03 (0.70−1.51), 1.72 (1.06−2.78), and 2.22 (1.16−4.23), respectively (p trend = 0.02). Increased alcohol consumption positively and consistently showed a relationship with increased risk of both prevalent and incident early-onset VMS. Refraining from alcohol consumption may help prevent bothersome VMS in premenopausal women.

Are serum estrogen concentrations associated with menopausal symptom bother among postmenopausal women? Baseline results from two MsFLASH clinical trials

OBJECTIVES

To evaluate whether single measurements of serum estradiol (E₂), estrone (E₁) and sex hormone-binding globulin (SHBG) concentration distinguishes between women with and without menopausal symptom bother.

STUDY DESIGN

We analyzed baseline data from two clinical trials conducted in 2012-2017: MsFLASH 03 (178 peri-/post-menopausal women aged 40-62 years with bothersome vasomotor symptoms, mean age 54) and MsFLASH 05 (181 post-menopausal women aged 45-70 years with moderate-to-severe vulvovaginal symptoms, mean age 61).

MAIN OUTCOME MEASURES

Symptom bother (hot flushes or flashes, night sweats, sweating, aching in muscles and joints, change in sexual desire, vaginal dryness during intercourse, and avoiding intimacy) in the past month was assessed using the Menopause-Specific Quality of Life questionnaire. Using logistic regression, we calculated the area under the receiver operating characteristic curve (AUC) values for E₁, E₂, and SHBG concentration in relation to being at least somewhat bothered (symptom bother score ≥3) by each symptom within each trial study population.

RESULTS

AUC values (95% confidence interval) ranged between 0.51 (0.41-0.60) and 0.62 (0.53, 0.72) for MsFLASH 03 and between 0.51 (0.42, 0.59) and 0.64 (0.53, 0.75) for MsFLASH 05. There was little evidence of associations between serum hormone levels and bother by a given menopausal symptom.

CONCLUSION

These findings do not support the clinical utility of a single measurement of serum of E₁, E₂, or SHBG concentrations in differentiating between women who are bothered by a given menopausal symptom and those who are not.

Association between vasomotor symptoms and sarcopenia assessed by L3 skeletal muscle index among Korean menopausal women

OBJECTIVE

To evaluate the association between vasomotor symptoms (VMS), skeletal muscle index (SMI), and sarcopenia in menopausal women.

METHODS

This cross-sectional study included 295 Korean menopausal women 40 to 65 years old who underwent abdominal computed tomography during routine health checkups between January 2014 and May 2016. The cross-sectional areas of adipose and skeletal muscles were measured at the L3 level using computed tomography. The SMI is defined as the sum of the skeletal muscle area (cm2)/height2 (m2). Sarcopenia was identified by an SMI of <34.9 cm2/m2. VMS were assessed using the Menopause Rating Scale.

RESULTS

The mean age of the participants was 54.93 ± 6.20 years. VMS were reported in 160 women (54.2%). Sarcopenia was more prevalent in women without VMS (18.5%) than in those with (6.9%). Multivariate logistic regression showed that the prevalence of sarcopenia was inversely associated with the prevalence of VMS (odds ratio, 0.32; 95% CI, 0.15-0.67). Moreover, the paraspinal muscle index was positively associated with the prevalence of VMS (odds ratio, 1.06; 95% CI, 1.01-1.11) after adjusting for age, body mass index, waist circumference, adipose tissue area, history of hormone therapy, systolic and diastolic blood pressures, total cholesterol, insulin resistance, alcohol intake, and exercise.

CONCLUSIONS

VMS are less common in women with sarcopenia than in those without and are positively associated with paraspinal muscle mass in Korean menopausal women. Further longitudinal studies are required to investigate the causal relationships and underlying mechanisms.

Moderate Consumption of Beer (with and without Ethanol) and Menopausal Symptoms: Results from a Parallel Clinical Trial in Postmenopausal Women

The menopausal transition can be a challenging period for women’s health and a trigger of uncomfortable symptoms. Beer is the main food source of isoxanthohumol, a precursor of 8-prenylnaringenin, the strongest phytoestrogen identified to date. As phytoestrogens are reported to reduce perimenopausal symptoms, we evaluated if a daily moderate consumption of beer with (AB) and without alcohol (NAB) could improve menopausal symptoms and modify cardiovascular risk factors. A total of 37 postmenopausal women were enrolled in a parallel controlled intervention trial and assigned to three study groups: 16 were administered AB (330 mL/day), 7 NAB (660 mL/day), and 14 were in the control group. After a 6-month follow-up of the 34 participants who finished the trial, both interventions (AB and NAB) significantly reduced the severity of the menopause-related symptoms (p-value AB vs. Control: 0.009; p-value NAB vs. Control: 0.033). Moreover, AB had a beneficial net effect on psychological menopausal discomforts compared to the control group. As the sex hormone profile did not differ significantly between the study groups, the effects of both types of beers (AB and NAB) are attributed to the non-alcoholic fraction of beer. Furthermore, moderate NAB consumption improved the lipid profile and decreased blood pressure in postmenopausal women.

Genetic Variation and Hot Flashes: A Systematic Review

CONTEXT

Approximately 70% of women report experiencing vasomotor symptoms (VMS, hot flashes and/or night sweats). The etiology of VMS is not clearly understood but may include genetic factors.

EVIDENCE ACQUISITION

We searched PubMed and Embase in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. We included studies on associations between genetic variation and VMS. We excluded studies focused on medication interventions or prevention or treatment of breast cancer.

EVIDENCE SYNTHESIS

Of 202 unique citations, 18 citations met the inclusion criteria. Study sample sizes ranged from 51 to 17 695. Eleven of the 18 studies had fewer than 500 participants; 2 studies had 1000 or more. Overall, statistically significant associations with VMS were found for variants in 14 of the 26 genes assessed in candidate gene studies. The cytochrome P450 family 1 subfamily A member 1 (CYP1B1) gene was the focus of the largest number (n = 7) of studies, but strength and statistical significance of associations of CYP1B1 variants with VMS were inconsistent. A genome-wide association study reported statistically significant associations between 14 single-nucleotide variants in the tachykinin receptor 3 gene and VMS. Heterogeneity across trials regarding VMS measurement methods and effect measures precluded quantitative meta-analysis; there were few studies of each specific genetic variant.

CONCLUSIONS

Genetic variants are associated with VMS. The associations are not limited to variations in sex-steroid metabolism genes. However, studies were few and future studies are needed to confirm and extend these findings.

Obesity, smoking, and risk of vasomotor menopausal symptoms: a pooled analysis of eight cohort studies

BACKGROUND

Frequent and severe vasomotor symptoms during menopause are linked with adverse health outcomes. Understanding modifiable lifestyle factors for the risk of vasomotor menopausal symptoms is important to guide preventive strategies.

OBJECTIVE

We investigated the associations between body mass index and smoking, their joint effects with the risk of vasomotor symptoms, and whether the associations differed by menopausal stage.

STUDY DESIGN

The International Collaboration for a Life Course Approach to Reproductive Health and Chronic Disease Events pooled data on 21,460 midlife women from 8 studies (median age, 50 years; interquartile range, 49-51 years) for the cross-sectional analysis. Four studies provided data for the prospective analysis (n=11,986). Multinomial logistic regression models with 4 categories of frequency/severity for the outcome of vasomotor symptoms were used to estimate relative risk ratios and 95% confidence intervals that were adjusted for within-study correlation and covariates.

RESULTS

At baseline, nearly 60% of the women experienced vasomotor symptoms. One-half of them were overweight (30%) or obese (21%), and 17% were current smokers. Cross-sectional analyses showed that a higher body mass index and smoking more cigarettes with longer duration and earlier initiation were all associated with more frequent or severe vasomotor symptoms. Never smokers who were obese had a 1.5-fold (relative risk ratio, 1.52; 95% confidence interval, 1.35-1.73) higher risk of often/severe vasomotor symptoms, compared with never smokers who were of normal-weight. Smoking strengthened the association because the risk of often/severe vasomotor symptoms was much greater among smokers who were obese (relative risk ratio, 3.02; 95% confidence interval, 2.41-3.78). However, smokers who quit at <40 years of age were at similar levels of risk as never smokers. Prospective analyses showed a similar pattern, but the association attenuated markedly after adjustment for baseline vasomotor symptoms. Furthermore, we found that the association between body mass index and vasomotor symptoms differed by menopausal status. Higher body mass index was associated with increased risk of vasomotor symptoms in pre- and perimenopause but with reduced risk in postmenopause.

CONCLUSION

High body mass index (≥25 kg/m2) and cigarette smoking substantially increased women's risk for experiencing frequent or severe vasomotor symptoms in a dose-response manner, and smoking intensified the effect of obesity. However, the effect of body mass index on the risk of vasomotor symptoms was opposite among postmenopausal women. Maintaining a normal weight before the menopausal transition and quitting smoking at <40 years of age may mitigate the excess risk of vasomotor symptoms in midlife.

Vasomotor, urogenital, psychological, and somatic symptoms in association with CYP1B1 polymorphisms in Slovak women of different menopausal status

OBJECTIVES

The aim of this study was to examine if the Arg48Gly, Ala119Ser, Leu432Val, and Asn453Ser polymorphisms in the CYP1B1 estrogen-metabolizing gene are associated with menopausal symptom experience in healthy Slovak women aged 40-60 years. We also investigated the possible association of other factors with menopausal symptoms, including health status, physical activity, reproductive history, psychological status, and smoking.

METHODS

The total sample consisted of 367 women (mean age 49.11 ± 5.86 years), encompassing 180 premenopausal (mean age 45.06 ± 3.81 years), 29 peri-menopausal (mean age 49.41 ± 3.94 years), and 158 postmenopausal (mean age 53.71 ± 4.54 years) women. The research comprised anthropometric and bioelectrical impedance analysis measurements (BIA), blood or saliva samples collected for DNA analysis, and a specific menopausal questionnaire.

RESULTS

CYP1B1 Arg48Gly is significantly associated with vasomotor, psychological, and somatic symptoms. It appears that the Gly/Gly genotype is a risk factor during the postmenopause and protective in the pre- and peri-menopause. CYP1B1 Ala119Ser was associated with all menopausal symptoms, with the Ser/Ser genotype increasing risk in the premenopause and offering protection in the peri- and postmenopause. Polymorphisms Leu432Val and Asn453Ser gave unequivocal results; independent of menopausal status, the Leu/Leu genotype was associated with increasing risk of vasomotor, urogenital, and psychological symptoms and the Asn/Asn genotype provided a protective effect against psychological symptoms.

CONCLUSIONS

Our results suggest possible associations of CYP1B1 polymorphisms with the occurrence and manifestation of particular menopausal symptoms in healthy mid-life Slovak women.

The Midlife Women’s Health Study – a study protocol of a longitudinal prospective study on predictors of menopausal hot flashes

Background

The Midlife Women’s Health Study (MWHS) was developed to address some of the gaps in knowledge regarding risk factors for hot flashes among generally healthy midlife women during their menopausal transition. This manuscript describes the methods from the study and the main findings that were published to date, with a focus on predictors of hot flashes. This study was initially funded to test the hypothesis that obesity is associated with an increased risk of hot flashes through mechanisms that involve ovarian failure, altered sex steroid hormone levels, and selected genetic polymorphisms.

Methods/Design

The MWHS was conducted between 2006 and 2015 as a prospective longitudinal population-based study of generally healthy midlife women (ages 45 to 54 years) during their natural menopausal transition. Women were eligible if they had intact uteri and both ovaries and reported having at least 3 menstrual periods in the last 12 months. Exclusion criteria included pregnancy, cancer, and use of hormonal/hormone-like supplements. Overall, 780 women were recruited into the study. The majority of study participants were followed for 4 to 7 years. At annual visits, women donated blood and urine samples, completed questionnaires, had a vaginal ultrasound, and had their anthropometric measurements taken.

Discussion

Several risk factors for menopausal hot flashes were identified or confirmed, including older age, perimenopausal status, current and former cigarette smoking, lower estradiol levels, lower progesterone levels, black race, and depressive symptoms. Factors that were associated with decreased odds of hot flashes included moderate alcohol consumption and more than 5 years of cessation of cigarette smoking. Body mass index was not associated with hot flashes. The MWHS has provided important information regarding hot flashes. The study methods are rigorous and can be easily adopted by research groups investigating naturally occurring menopausal hot flashes.

Association of genetic variation in the tachykinin receptor 3 locus with hot flashes and night sweats in the Women's Health Initiative Study

OBJECTIVE

Vasomotor symptoms (VMS, ie, hot flashes or night sweats) are reported by many, but not all, women. The extent to which VMS are genetically determined is unknown. We evaluated the relationship of genetic variation and VMS.

METHODS

In this observational study, we accessed data from three genome-wide association studies (GWAS) (SNP Health Association Resource cohort [SHARe], WHI Memory Study cohort [WHIMS+], and Genome-Wide Association Studies of Treatment Response in Randomized Clinical Trials [GARNET] studies, total n = 17,695) of European American, African American, and Hispanic American postmenopausal women aged 50 to 79 years at baseline in the Women's Health Initiative Study. We examined genetic variation in relation to VMS (yes/no) in each study and using trans-ethnic inverse variance fixed-effects meta-analysis. A total of 11,078,977 single-nucleotide polymorphisms (SNPs) met the quality criteria.

RESULTS

After adjustment for covariates and population structure, three SNPs (on chromosomes 3 and 11) were associated with VMS at the genome-wide threshold of 5 × 10 in the African American SHARe GWAS, but were not associated in the other cohorts. In the meta-analysis, 14 SNPs, all located on chromosome 4 in the tachykinin receptor 3 (TACR3) locus, however, had P < 5 × 10. These SNPs' effect sizes were similar across studies/participants' ancestry (odds ratio ∼1.5).

CONCLUSIONS

Genetic variation in TACR3 may contribute to the risk of VMS. To our knowledge, this is the first GWAS to examine SNPs associated with VMS. These results support the biological hypothesis of a role for TACR3 in VMS, which was previously hypothesized from animal and human studies. Further study of these variants may lead to new insights into the biological pathways involved in VMS, which are poorly understood.

Treatment of climacteric symptoms with an ammonium succinate-based dietary supplement: a randomized, double-blind, placebo-controlled trial

Peri- and postmenopausal women commonly suffer from climacteric symptoms. We evaluated the effectiveness and safety of dietary supplement Amberen to relieve vasomotor and psychosomatic symptoms during the course of a 3-month, randomized, double-blind, placebo-controlled study. General clinical assessment, evaluation using the Greene climacteric test and Spielberger-Hanin test, determination of plasma levels of gonadotropins, estradiol, leptin and apolipoproteins were used to evaluate 42-60-year-old women with vasomotor and psychosomatic menopausal symptoms. One hundred and twenty-five women were enrolled in the study and randomized between two groups. Based on the Greene test results, there was a statistically significant improvement (р < 0.05) in 13 out of 21 menopausal symptoms in women who took Amberen. During the course and by the end of the study, patients showed statistically significant changes in the levels of estradiol, gonadotropins and leptin, and decreases in body weight and waist circumference. Spielberger-Hanin test showed that Amberen stabilizes patients' psychological state with a statistically significant decrease in anxiety, increased stress resistance and improved adaptability. Comparative analysis of the vital signs measurements, blood tests and urinalysis did not show any negative effects of Amberen on the patients. Our findings indicate that Amberen can be considered a method of choice to relief mild/moderate climacteric symptoms.

Risk factors for hot flashes among women undergoing the menopausal transition: baseline results from the Midlife Women's Health Study

OBJECTIVE

The aim of this study was to examine the associations of demographic characteristics, health behaviors, and hormone concentrations with the experience of any, current, more severe, and more frequent midlife hot flashes.

METHODS

Baseline data from 732 women aged 45 to 54 years who were enrolled in the Midlife Women's Health Study were analyzed. A clinic visit was conducted to collect blood samples for hormone assays and to measure ovarian volume using transvaginal ultrasound. A self-administered questionnaire ascertained information on demographic factors, health habits, and hot flash history. Multivariable logistic regression was conducted to examine associations between potential risk factors and hot flash outcomes.

RESULTS

Approximately 45% of participants reported experiencing midlife hot flashes. In covariate-adjusted models, older age, perimenopause status, current and past cigarette smoking, and depressive symptoms were significantly associated with increased odds of all of the hot flash outcomes. In addition, history of oral contraceptive use was associated with increased odds of any hot flashes. In contrast, higher current alcohol intake was significantly associated with decreased odds of any, current, and more severe hot flashes. Higher estradiol and progesterone concentrations were significantly associated with decreased odds of all hot flash outcomes.

CONCLUSIONS

Although the temporality of such associations is not known because of the cross-sectional nature of the data, these observed relationships can help to identify women at risk for hot flashes.

Risk Factors for Extended Duration and Timing of Peak Severity of Hot Flashes

OBJECTIVE

To identify risk factors associated with the duration of hot flashes and the time of peak hot flash severity in mid-life women.

METHODS

A cohort of 647 women reporting hot flashes were followed for 1-7 years, with survey data and hormone measurements. Survival analysis determined the association of risk factors with the duration of hot flashes. Linear regression determined the association of risk factors with the time of peak severity. Final models were determined through stepwise model selection.

RESULTS

Average hot flash duration was 2.5 years (range: 1-33), with peak severity on average at 2.96 years (range: 1-20). Duration of hot flashes was associated with race, education, menopause status, smoking history, BMI, alcohol consumption, leisure activity levels, and levels of estradiol and progesterone. In the final model, only race, alcohol consumption, leisure activity, and menopause were retained. White women had significantly shorter hot flash durations than non-white women. Women consuming at least 12 alcoholic drinks in the previous year had a significantly shorter duration of hot flashes with a smaller effect of hot flash duration on increasing in time to peak severity compared to those who consumed less than 12 alcoholic drinks in that year. Higher serum progesterone levels were associated with later peak severity if the duration of the hot flashes was less than 2 years and an earlier peak severity otherwise.

CONCLUSIONS

These results suggest that some behaviors (such as moderate alcohol consumption) are associated with shorter durations of hot flashes, and that progesterone was associated with the dynamics of hot flash severity.

A potentially functional variant in the serotonin transporter gene is associated with premenopausal and perimenopausal hot flashes

OBJECTIVE

An increase in the use of selective serotonin reuptake inhibitors (SSRIs) and/or serotonin-norepinephrine reuptake inhibitors (SNRIs) to relieve menopausal hot flashes (HFs) has been observed recently. However, response to them has been heterogeneous. We hypothesized that this heterogeneity might be partially attributed to genetic variations in genes encoding the serotonin and/or norepinephrine transporters (SLC6A4 and SLC6A2). As a first step in testing the role of genetics in response to SSRIs/SNRIs, we examined the association between HFs and genetic variants within these two genes.

METHODS

We tested 29 haplotype-tagging single nucleotide polymorphisms within SLC6A4 and SLC6A2 for their association with HFs separately for European-American (396 cases and 392 controls) and African-American (125 cases and 81 controls) premenopausal and perimenopausal women.

RESULTS

We found that the minor allele of SLC6A4_rs11080121 was associated with protection against HFs (odds ratio, 0.75; 95% CI, 0.60-0.94) only in European-American women. Bioinformatics analyses indicated that rs11080121 is fully correlated with rs1042173 in the 3' untranslated region of SLC6A4. The minor allele of rs1042173 seems to disrupt a conserved binding site for hsa-miR-590-3p microRNA.

CONCLUSIONS

Disruption of a microRNA binding site leads to higher expression of SLC6A4, higher expression of SLC6A4 leads to depletion of serotonin in synaptic clefts, and depletion of serotonin triggers the presynaptic autoreceptor feedback mechanism to produce more serotonin, which is protective against HFs. This is the first study to test the association between HFs in both European-American and African-American premenopausal and perimenopausal women and genetic variants in two neurotransmitter transporter genes, SLC6A2 and SLC6A4. This information can be used in tailoring the pharmaceutical use of SSRIs/SNRIs for HF relief.

Factors that may influence the experience of hot flushes by healthy middle-aged women

BACKGROUND

Interest in menopausal symptoms in general and hot flushes (HFs) in particular has grown in recent years. This is mostly due to increased awareness and the vast impact these symptoms have on women's lives. Despite the high prevalence of women who experience HFs, a definitive etiology for HFs is yet to be found. Our objective was to review the current literature dealing with associated factors for experiencing HFs and to provide a synthesized overview on this common and often debilitating condition.

METHODS

We systematically searched the English-language literature in the PubMed database using relevant key words and included only those articles that contained information on associated factors for HFs in generally healthy midlife women.

RESULTS

Both conflicting scientific results between studies documenting factors that influence HFs and the lack of validated measuring tools make it difficult to truly pinpoint associated factors for HFs. Nonetheless, we identified the following clusters of associated factors: the menopausal stages, sex steroid hormones, other endocrine agents, genetic polymorphisms, race/ethnicity, body mass index (BMI) and obesity, mood disorders, smoking, soy isoflavones and phytoestrogens, alcohol consumption, and physical activity.

CONCLUSIONS

No single associated factor was consistently identified as having a major role in experiencing HFs. More resources should be directed to develop a unified study system along with multivariable analyses to get a better understanding of this condition, which often imposes a tremendous social and personal toll on the women who experience it.

Menopausal symptoms and the risk of young-onset breast cancer

BACKGROUND

Women with menopausal symptoms have been reported to have reduced risk of breast cancer, possibly reflecting differences in endogenous hormone levels. We examined the associations between menopausal symptoms and breast cancer in women under age 50.

METHODS

We carried out a sister-controlled case-control study, the Two Sister Study, comparing 1422 women with breast cancer diagnosed before age 50 and their 1669 sisters who were free of breast cancer and had enrolled in the prospective Sister Study cohort. History and age at first occurrence of menopause-associated symptoms (e.g. hot flashes, poor sleep or night sweats) were ascertained using computer-assisted telephone interviews. To equalise opportunity for exposure, we assessed exposures in relation to a sibship-based index age (the minimum of the age at diagnosis of the case sister and the age at interview of her control sister(s)), and estimated odds ratios using conditional logistic regression with adjustment for menopausal status and birth order.

FINDINGS

Having had menopause-associated symptoms (n=706) prior to the index age was associated with reduced risk of young-onset breast cancer (odds ratio (OR), 0.49; 95% confidence interval (CI), 0.40-0.61). Similar results were seen for hot flashes and for "other" menopausal symptoms. The association between menopausal symptoms and breast cancer risk was somewhat stronger for oestrogen receptor positive tumours than for oestrogen receptor negative tumours (heterogeneity p=0.07). Menopausal status, age at menopause, BMI and hormone replacement therapy did not modify the associations, but the inverse association between menopausal symptoms and breast cancer attenuated with increasing index age (p<0.01).

INTERPRETATION

Menopause-associated symptoms were associated with markedly reduced risk of young-onset breast cancer. Further studies are needed to confirm the association and elucidate possible pathways.

Genetic polymorphisms in the aryl hydrocarbon receptor signaling pathway as potential risk factors of menopausal hot flashes

OBJECTIVE

We sought to determine if genetic polymorphisms in the aryl hydrocarbon receptor signaling pathway are associated with menopausal hot flashes via hormone levels.

STUDY DESIGN

Women (n = 639) aged 45-54 years completed a study survey and provided blood for genetic and hormone analyses. The associations were analyzed using multivariable logistic regression and generalized linear models.

RESULTS

Women carrying CYP1B1 (rs1800440) GG genotype had 3-fold greater odds of experiencing hot flashes for ≥1 year compared to the AA genotype (adjusted odds ratio [OR], 3.05; 95% confidence interval [CI], 1.12-8.25). Adding serum estradiol concentrations to the confounder-adjusted model resulted in a nonsignificant association (adjusted OR, 2.59; 95% CI, 0.91-7.18). Carriers of both CYP1B1 (rs1800440) G and CYP1B1 (rs1058636) G alleles had higher odds of experiencing hot flashes for ≥1 year compared to women homozygous for the major alleles (adjusted OR, 1.77; 95% CI, 1.06-2.96), even after adjustment for serum estradiol.

CONCLUSION

CYP1B1 is associated with menopausal hot flashes via pathways that may involve changes in serum estradiol concentration.

Joint effects of smoking and gene variants involved in sex steroid metabolism on hot flashes in late reproductive-age women

BACKGROUND

Although smoking has a known association with hot flashes, the factors distinguishing smokers at greatest risk for menopausal symptoms have not been well delineated. Recent evidence supports a relationship between menopausal symptoms and variants in several genes encoding enzymes that metabolize substrates such as sex steriods, xenobiotics, and catechols. It is currently not known whether the impact of smoking on hot flashes is modified by the presence of such variants.

OBJECTIVE

The objective of the study was to investigate the relationship between smoking and hot flash occurrence as a function of genetic variation in sex steroid-metabolizing enzymes.

METHODS

A cross-sectional analysis of data from the Penn Ovarian Aging study, an ongoing population-based cohort of late reproductive-aged women, was performed. Smoking behavior was characterized. Single-nucleotide polymorphisms in five genes were investigated: COMT Val158Met (rs4680), CYP1A2*1F (rs762551), CYP1B1*4 (Asn452Ser, rs1800440), CYP1B1*3 (Leu432Val, rs1056836), and CYP3A4*1B (rs2740574).

RESULTS

Compared with nonsmokers, European-American COMT Val158Met double-variant carriers who smoked had increased odds of hot flashes [adjusted odds ratio (AOR) 6.15, 95% confidence interval (CI) 1.32-28.78)]; European-American COMT Val158Met double-variant carriers who smoked heavily had more frequent moderate or severe hot flashes than nonsmokers (AOR 13.7, 95% CI 1.2-154.9). European-American CYP 1B1*3 double-variant carriers who smoked described more frequent moderate or severe hot flashes than nonsmoking (AOR 20.6, 95% CI 1.64-257.93) and never-smoking (AOR 20.59, 95% CI 1.39-304.68) carriers, respectively. African-American single-variant CYP 1A2 carriers who smoked were more likely to report hot flashes than the nonsmoking carriers (AOR 6.16, 95% CI 1.11-33.91).

CONCLUSION

This is the first report demonstrating the effects of smoking within the strata of gene variants involved in sex steroid metabolism on hot flashes in late reproductive-age women. The identification of individuals with a genetic susceptibility to smoking-related menopausal symptoms could contribute to interventions targeted at reducing reproductive morbidity both in the menopause and across the reproductive life course.

The association of cytochrome P450 1B1 Leu432Val polymorphism with biological markers of health and menopausal symptoms in Slovak midlife women

OBJECTIVE

In this study, the CYP1B1 polymorphism was examined in relationship to recognized risk factors for cardiovascular disease. In particular, this study focused on plasma lipid levels, atherogenic indices, and body composition. Furthermore, this polymorphism was analyzed as a predisposing factor for menopausal symptoms among women during midlife, subdivided according to their menopause status.

METHODS

A total of 399 women aged from 39 to 60 years were examined. They were recruited from the western and middle parts of Slovakia. Participants were interviewed during their medical examination, and they were investigated with respect to a variety of aspects such as anthropometric and medical aspects, and a menopause-specific questionnaire was included. The participants provided a saliva or blood sample for DNA genotyping and a blood sample for biochemical analysis.

RESULTS

The Leu432Val genotype demonstrated statistically significant associations with triglycerides, with the ratio of total cholesterol to high-density lipoprotein cholesterol, and with the logarithm of the ratio of plasma concentration of triglycerides to high-density lipoprotein cholesterol in women in their reproductive period. The mean values were significantly lower in women carrying the Val/Val genotype. Four atherogenic indices showed a decreasing trend in relationship to the CYP1B1 genotypes in women during their reproductive period (in the following order of magnitude: Leu/Leu + Leu/Val vs Val/Val) and an increasing trend among postmenopausal women in the same order. Furthermore, the Val/Val genotype diminished experiences of bloated stomach, of vaginal dryness in perimenopausal and postmenopausal women, and of palpitations in premenopausal women.

CONCLUSIONS

The Leu432Val polymorphism may be associated with the lipid profile in midlife women. Moreover, this polymorphism may influence the risk of some menopausal symptoms.

Vasomotor symptoms and menopause: findings from the Study of Women's Health across the Nation

Vasomotor symptoms (VMS), or hot flashes and night sweats, are often considered the cardinal symptoms of menopause. SWAN, one of the largest and most ethnically diverse longitudinal studies of the menopausal transition, has allowed unique insights into VMS. Specifically, SWAN has helped yield important information about the prevalence of, racial/ethnic differences in, risk factors for, and implications of VMS for midlife women's mental and physical health. We have reviewed the literature on VMS, emphasizing findings that have emerged from SWAN and new areas of inquiry in the area of VMS.

A genetic polymorphism in the CYP19A1 gene and the risk of hypertension among midlife women

OBJECTIVE

To test whether a synonymous single nucleotide polymorphism (A→G; rs700518) in the CYP19A1 gene, which encodes the enzyme aromatase, is associated with an increased risk for hypertension of midlife women.

METHODS

In a cross-sectional study, 639 midlife women were recruited. Eligible women had their blood pressure, weight and height measured, and donated a blood sample for hormone and genetic analyses. The participants also completed a detailed study survey. Women were grouped according to their genotype, blood pressure measurements, and medical history. The data were analyzed using logistic and linear regression models. The study had 80% power to detect small differences in mean systolic blood pressure (SBP; 4.5 mmHg) and diastolic blood pressure (DBP; 3 mmHg).

RESULTS

The selected polymorphism was significantly associated with hypertension and SBP in unadjusted analyses. Interestingly, women with hypertension were more likely to be homozygous for the A allele (AA) compared to women who were not categorized as having hypertension. Further, the mean SBP was significantly higher for women who were homozygous for the A allele when compared to women carrying the other genotypes (AG or GG). The unadjusted association between DBP values and genotype was of borderline statistical significance (p=0.07). However, after adjustment for potential confounders (age, race, body mass index (BMI), smoking and physical activity), the associations between genotype and hypertension/blood pressure were attenuated and not statistically significant.

CONCLUSION

The rs700518 polymorphism in the CYP19A1 is not associated with hypertension in our sample of midlife women. Other factors, including race and BMI, appear to play a greater role.

Menopausal hot flushes and night sweats: where are we now?

OBJECTIVE

An overview of the current knowledge on the etiology and treatment of vasomotor symptoms in postmenopausal women.

MATERIALS AND METHODS

Acknowledged experts in the field contributed a brief assessment of their areas of interest which were combined and edited into the final manuscript.

RESULTS

Women around the world experience vasomotor symptoms as they enter and complete the menopause transition. Vasomotor symptoms, specifically hot flushes, are caused by a narrowing of the thermoneutral zone in the brain. This effect, although related to estrogen withdrawal, is most likely related to changes in central nervous system neurotransmitters. Peripheral vascular reactivity is also altered in symptomatic women. Estrogen replacement therapy is the most effective treatment for hot flushes. Of the other interventions investigated, selective serotonin and selective norepinephrine reuptake inhibitors and gabapentin show efficacy greater than placebo. Objective monitoring of hot flushes indicates a robust improvement with hormone replacement therapy but little to no change with placebo. These data suggest that the subjective assessment of responses to therapy for vasomotor symptom results in inaccurate data. Hot flushes have recently been associated with increased cardiovascular risks and a lower incidence of breast cancer, but these data require confirmation.

CONCLUSIONS

Vasomotor symptoms are experienced by women of all ethnic groups. They are caused by changes in the central nervous system associated with estrogen withdrawal and are best treated with estrogen replacement therapy. Objective monitoring of hot flushes indicates that placebo has little to no effect on their improvement. Subjective assessments of hot flushes in clinical trials may be inaccurate based on objective measurement of the frequency of hot flushes. Based on preliminary reports, women experiencing hot flushes have an increased risk of cardiovascular disease and a reduced incidence of breast cancer.

Genetic polymorphisms and obesity influence estradiol decline during the menopause

OBJECTIVES

Obesity and genetic variation in aromatase and type 1 17-β hydroxysteroid dehydrogenase (HSD) could influence the E2 trajectory of decline during the menopause transition.

DESIGN AND PARTICIPANTS

E2 trajectories during the menopause transition (phenotype) were identified using 5934 data points acquired annually from 681 women in Study of Women's Health across the Nation (SWAN), a multiethnic study of the mid-life. E2 trajectories were related to CYP19 and type I 17-βHSD single-nucleotide polymorphisms (SNPs) and obesity.

RESULTS

(log) E2 trajectories began to decline precipitously 2 years before the final menstrual period (FMP). The trajectory of the (log) E2 decline varied with genotypes and obesity. (log) E2 rates of decline were greater in nonobese women than in obese women, P < 0·05. Women with the CYP19rs936306 CT variant had (log) E2 rate of decline that was 54% as rapid as the rate of decline of women with the TT variant, P < 0·05. (log) E2 rate of decline in women with the CYP19rs749292 GG variant was two-thirds the rate of (log) E2 decline in women with the AG variant, P < 0·05. (log) Rates of E2 decline with 17-βHSD SNPs (rs2830, rs592389, and rs615942) varied according to genotype within obesity groups. Within each obesity group, (log) E2 rate of decline was greater in heterozygous variants and much less in homozygotes (P < 0·05). Obese women with selected CYP19 and 17-β HSD gene variants had remarkably different E2 trajectories around the FMP, resulting in different postmenopausal E2 levels. The rate of the E2 decline and the subsequent postmenopausal E2 levels may be relevant to oestrogen-sensitive chronic diseases including cancers.

Effect of hormone metabolism genotypes on steroid hormone levels and menopausal symptoms in a prospective population-based cohort of women experiencing the menopausal transition

OBJECTIVE

This study evaluated whether genes involved in the metabolism of steroid hormones are associated with hormone levels or menopausal symptoms.

METHODS

We used a population-based prospective sample of 436 African American (AA) and European American (EA) women who were premenopausal at enrollment and were followed longitudinally through menopause. We evaluated the relationship between steroid hormone metabolism genotypes at COMT, CYP1A2, CYP1B1, CYP3A4, CYP19, SULT1A1, and SULT1E1 with hormone levels and menopausal features.

RESULTS

In EA women, SULT1E1 variant carriers had lower levels of dehydroepiandrosterone sulfate, and SULT1A1 variant carriers had lower levels of estradiol, dehydroepiandrosterone sulfate, and testosterone compared with women who did not carry these variant alleles. In AA women, CYP1B1*3 genotypes were associated with hot flashes (odds ratio [OR], 0.62; 95% CI, 0.40-0.95). Interactions of CYP1A2 genotypes were associated with hot flashes across menopausal stage (P = 0.006). Interactions of CYP1B1*3 (P = 0.02) and CYP1B1*4 (P = 0.03) with menopausal stage were associated with depressive symptoms. In EA women, SULT1A1*3 was associated with depressive symptoms (OR, 0.53; 95% CI, 0.41-0.68) and hot flashes (OR, 2.08; 95% CI, 1.64-2.63). There were significant interactions between SULT1A1*3 and hot flashes (P < 0.001) and between SULT1A1*2 and depressive symptoms (P = 0.007) on menopausal stage, and there were race-specific effects of SULT1A1*2, SULT1A1*3, CYP1B1*3, and CYP3A4*1B on menopause.

CONCLUSIONS

Our results suggest that genotypes are associated with the occurrence of menopause-related symptoms or the timing of the menopausal transition.

Menopausal hot flashes: a review of physiology and biosociocultural perspective on methods of assessment

Hot flashes continue to be a troublesome problem for menopausal women the world over. After >50 y of research, we still do not understand the etiology and mechanism of hot flashes, nor do we know how estrogen, the major pharmaceutical treatment, works to reduce hot flashes. We are gaining insight into sociocultural complexities that may affect how and whether women report hot flashes. And we are becoming more sophisticated in our research tools (be it questionnaires, physiological monitors, or brain imaging techniques). New aspects of hot flash research, including neuroimaging and the study of genetic polymorphisms, when combined with increasingly nuanced ways of asking questions of culturally distinct populations, provide challenges but rich complexity from which a better understanding will emerge.

Vasomotor hot flushes and 24-hour ambulatory blood pressure in normotensive women: A placebo-controlled trial on post-menopausal hormone therapy

BACKGROUND

Blood pressure (BP) is one of the most powerful determinants of cardiovascular risk in women. This risk may differ between post-menopausal women with and without vasomotor hot flushes, possibly indicating different vascular responses to hormone therapy (HT). Thus, we compared in a clinical trial the effect of HT on ambulatory BP in normotensive, recently post-menopausal women with or without severe hot flushes.

METHODS

A total of 147 women recorded prospectively their hot flushes for 2 weeks; 70 women were symptomatic (>or=7 moderate/severe hot flush episodes/day), whereas 77 women were defined as asymptomatic (<or=3 mild hot flush episodes/day). Women were treated for 6 months with either transdermal estradiol, oral estradiol with or without medroxyprogesterone acetate, or placebo.

RESULTS

In symptomatic women decreases in BPs were seen during estradiol use. In contrast, in asymptomatic women receiving oral but not transdermal estradiol, increases in 24-h and day-time systolic and diastolic BPs were encountered.

CONCLUSION

Hot flushes modify the HT-mediated responses in ambulatory BP. In asymptomatic women oral but not transdermal estradiol show potentially harmful cardiovascular effect by increasing BP. Our results give additional justification to prescribing HT primarily for the treatment of troublesome hot flushes and avoiding HT in women without vasomotor symptoms.

Menopausal hot flush: is it only a nuisance or also a marker of cardiovascular disease risk?

Hot flush is one of the most commonly reported symptoms during menopause; however, it is not experienced by all menopausal women, for reasons that remain unclear. In this review, we present current evidence that link hot flushes with cardiovascular disease, suggesting that the persistence of hot flushes many years after the menopause may represent a marker of an underlying disorder that increases the risk for cardiovascular disease.

Menopausal hot flushes revisited

Vasomotor symptoms are generally recognized as one of the most common symptoms, or signs, of the menopause, together with menstrual cycle changes. The etiology of hot flushes is unknown, although several mechanisms have been implicated. The reduction in hot flushes with estrogen replacement therapy suggests a hormonal etiology. However, the levels of estrogens do not appear to correlate with hot flushes. It seems more likely that the rate of change of plasma estrogen concentrations influences the thermoregulatory system via the hypothalamus. During the past few decades, remedies for the treatment of hot flushes have advanced from simple sedatives and purgatives to the use of ovarian extracts and, finally, to pharmacological estrogen preparations. In view of the contraindications and side-effects of estrogens and progestogens in postmenopausal women, however, there is a need to consider treatments other than hormone replacement for the relief of hot flushes.

Cigarette smoking, androgen levels, and hot flushes in midlife women

OBJECTIVE

To test the hypothesis that cigarette smoking is associated with hot flushes through a mechanism involving androgen levels, progesterone levels, sex hormone-binding globulin levels, or the ratio of androgens to estrogens.

METHODS

Women with and without hot flushes were recruited from Baltimore, Maryland, and the surrounding counties. Women were between 45 and 54 years of age, with at least three menstrual periods in the previous 12 months, and were not postmenopausal. Study participants completed a questionnaire and gave a blood sample for hormone measurements.

RESULTS

Current smokers had significantly higher androstenedione levels and a higher androgen-to-estrogen ratio than never smokers. Current smokers had significantly lower progesterone levels compared with never smokers. Former and current cigarette smokers had increased odds of experiencing hot flushes compared with never smokers (former: odds ratio [OR] 1.41, 95% confidence interval [CI] 0.99-2.01; current: OR 2.43, 95% CI 1.28-4.62). This association, however, was not attenuated by the addition of hormones to the smoking and hot-flush model.

CONCLUSION

Cigarette smoking is associated with hot flushes through a mechanism that may not involve alterations in hormone levels or their ratios.

LEVEL OF EVIDENCE

II.