Cigarette smoking and effects on hormone function in premenopausal women

The influence of ovarian hormones on the putative mechanisms that promote female nicotine use

Nicotine use is driven by pleasurable effects, but following chronic exposure, nicotine use becomes largely driven by the desire need to avoid withdrawal symptoms. Current cessation strategies focusing on alleviating withdrawal, but current cessation interventions are less effective for women than men. Also, hormone fluctuations across the menstrual cycle appear to impact use patterns, withdrawal severity, and treatment efficacy. This raises important questions regarding optimal quit dates and the application of hormone interventions to alleviate withdrawal in women. This review surveys the existing literature assessing the impact of ovarian hormones on nicotine withdrawal severity. This is an important issue because women seeking cessation treatments may be using hormone-based contraceptives or hormone replacement post-menopause. Hormone interventions may also offer a novel treatment avenue that is more effective than current cessation approaches. Future work in this area is important for reducing health disparities produced by excessive nicotine use in women.

Association between secondhand smoke exposure and serum sex hormone concentrations among US female adults: a cross-sectional analysis using data from the National Health and Nutrition Examination Survey, 2013-2016

OBJECTIVE

To estimate the association between secondhand smoke (SHS) exposure and serum sex hormone concentrations in female adults (never smokers and former smokers).

DESIGN

Cross-sectional analysis.

SETTING

US National Health and Nutrition Examination Survey, 2013-2016.

OUTCOME MEASURES

Serum sex hormone measures included total testosterone (TT) and oestradiol (E2), sex hormone-binding globulin (SHBG), the ratio of TT and E2 and free androgen index (FAI). Isotope dilution-liquid chromatography tandem mass spectrometry was used to measure serum TT and E2. SHBG was measured using immunoassay. The ratio of TT and E2 and FAI were calculated. SHS exposure was defined as serum cotinine concentration of 0.05-10 ng/mL.

PARTICIPANTS

A total of 622 female participants aged ≥20 years were included in the analysis.

RESULTS

For never smokers, a doubling of serum cotinine concentration was associated with a 2.85% (95% CI 0.29% to 5.47%) increase in TT concentration and a 6.29% (95% CI 0.68% to 12.23%) increase in E2 in fully adjusted models. The never smokers in the highest quartile (Q4) of serum cotinine level exhibited a 10.30% (95% CI 0.78% to 20.72%) increase in TT concentration and a 27.75% (95% CI 5.17% to 55.17%) increase in E2 compared with those in the lowest quartile (Q1). For former smokers, SHBG was reduced by 4.36% (95% CI -8.47% to -0.07%, p for trend=0.049) when the serum cotinine level was doubled, and the SHBG of those in Q4 was reduced by 17.58% (95% CI -31.33% to -1.07%, p for trend=0.018) compared with those in Q1.

CONCLUSION

SHS was associated with serum sex hormone concentrations among female adults. In never smokers, SHS was associated with increased levels of TT and E2. In former smokers, SHS was associated with decreased SHBG levels.

Exploring the triggers of premature and early menopause in India: a comprehensive analysis based on National Family Health Survey, 2019-2021

Due to ovarian insufficiency, some women attain menopause at an early age due to lifestyle factors and hormonal imbalances. Menopause occurring before the age of 40 is premature and between 40 and 44 years age is early, since the natural age of menopause lies between 45 and 50. The study estimated the prevalence of both premature and early menopause, and examined the potential associated factors that could trigger its occurrence in India. The National Family Health Survey, conducted during 2019-2021, was used to fulfil the study objective. The study sample was divided into two parts, with age group 15-39 and 40-44 for estimating premature and early menopause, respectively. Cox-proportional hazard model was used for the multivariate analysis. The estimated prevalence of premature menopause is 2.2% and early menopause is 16.2%. Lower educational level, poor economic condition, smoking, fried food consumption, early age at menarche are some of the significant explanatory factors. In India, both the proportion and the absolute number of post-menopausal women are growing, therefore it is critical to revamp public reproductive healthcare facilities to include menopausal health segment in women's health as well. Future detailed micro-studies would help in better understanding of the premature or early menopausal cases.

Association of serum leptin and ghrelin levels with smoking status on body weight: a systematic review and meta-analysis

Background and aims

Smoking cigarettes is a major global health problem that affects appetite and weight. The aim of this systematic review was to determine how smoking affected plasma leptin and ghrelin levels.

Methods

A comprehensive search of PubMed, Scopus, Web of Science, and Ovid was conducted using a well-established methodology to gather all related publications.

Results

A total of 40 studies were included in the analysis of 11,336 patients. The overall effect showed a with a mean difference (MD) of -1.92[95%CI; -2.63: -1.20] and p = 0.00001. Subgroup analysis by study design revealed significant differences as well, but with high heterogeneity within the subgroups (I2 of 82.3%). Subgroup by sex showed that there was a significant difference in mean difference between the smoking and non-smoking groups for males (MD = -5.75[95% CI; -8.73: -2.77], p = 0.0002) but not for females (MD = -3.04[95% CI; -6.6:0.54], p = 0.10). Healthy, pregnant, diabetic and CVD subgroups found significant differences in the healthy (MD = -1.74[95% CI; -03.13: -0.35], p = 0.01) and diabetic (MD = -7.69[95% CI, -1.64: -0.73], p = 0.03). subgroups, but not in the pregnant or cardiovascular disease subgroups. On the other hand, the meta-analysis found no statistically significant difference in Ghrelin serum concentration between smokers and non-smokers (MD = 0.52[95% CI, -0.60:1.63], p = 0.36) and observed heterogeneity in the studies (I2 = 68%).

Conclusion

This study demonstrates a correlation between smoking and serum leptin/ghrelin levels, which explains smoking's effect on body weight.

Systematic review registration

https://www.crd.york.ac.uk/ prospero/display_record.php, identifier (Record ID=326680).

Study on depletion of ovarian function and late-life chronic diseases in India

OBJECTIVE

The current study aims to understand premature and early menopausal age in association with chronic conditions.

METHODS

The present cross-sectional study analyzed nationally representative data from LASI (Longitudinal Aging Study in India) from 2017 to 2018. Bivariate analysis including cross-tabulation and χ2 tests were performed. Further multiple regression analysis was performed, using the generalized linear model of logit link.

RESULTS

Approximately 2533 (8%) older women reported that they had experienced premature menopause (before age 40), while 3889 (12.4%) reported having early menopause (age 40-44). The likelihood of a woman with premature menopause developing cardiovascular diseases (CVDs) is 15% higher (adjusted odds ratio [AOR], 1.15; P < 0.05) than those who do not experience premature menopause, while women with early menopause have a 13% higher risk (AOR, 1.13; P < 0.05). For women who experienced premature menopause and were also smokers, the probability of developing CVDs was higher. Other chronic diseases such as bone or joint problems, diabetes, and eye vision problems were also shown to be significant health problems among women who had premature ovarian failure.

CONCLUSION

Our results show significant association between women with premature or early depletion of ovarian function and chronic health conditions such as cardiovascular diseases, bone or joint problems, vision problems, and neurological or psychiatric disorders at their later life ages. Comprehensive strategies in the form of lifestyle changes may regulate hormonal levels and allow the body to reach menopause at the appropriate age.

Association between smoking cessation and non-alcoholic fatty liver disease using NAFLD liver fat score

Background

Smoking is well known to be associated with a higher prevalence and incidence of liver diseases such as advanced fibrosis. However, the impact of smoking on developing nonalcoholic fatty liver disease remains controversial, and clinical data on this is limited. Therefore, this study aimed to investigate the association between smoking history and nonalcoholic fatty liver disease (NAFLD).

Methods

Data from the Korea National Health and Nutrition Examination Survey 2019-2020 were used for the analysis. NAFLD was diagnosed according to an NAFLD liver fat score of >-0.640. Smoking status was classified as into nonsmokers, ex-smokers, and current smokers. Multiple logistic regression analysis was conducted to examine the association between smoking history and NAFLD in the South Korean population.

Results

In total, 9,603 participants were enrolled in this study. The odds ratio (OR) for having NAFLD in ex-smokers and current smokers in males was 1.12 (95% confidence interval [CI]: 0.90-1.41) and 1.38 (95% CI: 1.08-1.76) compared to that in nonsmokers, respectively. The OR increased in magnitude with smoking status. Ex-smokers who ceased smoking for <10 years (OR: 1.33, 95% CI: 1.00-1.77) were more likely to have a strong correlation with NAFLD. Furthermore, NAFLD had a dose-dependent positive effect on pack-years, which was 10 to 20 (OR: 1.39, 95% CI: 1.04-1.86) and over 20 (OR: 1.51, 95% CI: 1.14-2.00).

Conclusion

This study found that smoking may contribute to NAFLD. Our study suggests cessation of smoking may help management of NAFLD.

Dietary, Psychological and Lifestyle Factors Associated with Premenstrual Symptoms

Purpose

To measure the associations of diet, psycological distress, and lifestyle factors with premenstrual symptoms (PMSx) in women in Riyadh, Saudi Arabia.

Patients and Methods

An interview-based, cross-sectional study was conducted on 1831 women aged 18-50 years seen in primary healthcare centers and teaching institutes in Riyadh from December 2015 to June 2016. Question topics included sociodemographics, physical activity, smoking, and dietary habits information. PMSx were assessed using a symptom checklist with 6 domains: anxiety/mood changes; abdominal/back/joint pain; increased appetite/weight gain, breast pain/tenderness, severe headache, and ≥3 PMS symptoms (any). Multivariable logistic regression analyses were conducted to provide adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for factors associated with each PMSx domain.

Results

Except for breast pain, drinking >5 cups of Arabic coffee was associated with increased odds of anxiety/mood [aOR 2.44 (95% CI 1.44, 4.12)], pain [1.83 (1.13, 2.98)], appetite/weight gain [1.66 (1.10, 2.50)], headache [1.57 (1.00, 2.56)] and ≥3 symptoms [1.50 (1.07, 2.11)]. A significant association was noted between sugar intake and anxiety/mood symptoms [1.53 (1.07, 2.19)] and abdominal/back pain symptoms [1.84 (1.17, 2.88)]. Increased severity of psychological distress was associated with all symptom domains: anxiety/mood [2.75 (1.92, 3.94)]; pain [1.45 (0.92, 2.28)]; appetite/weight gain [2.01 (1.53, 2.65)]; breast pain [2.19 (1.68, 2.88)]; headache [1.86 (1.37, 2.54)] and ≥3 symptoms [3.52 (2.49, 4.95)]. Low physical activity was significantly associated with odds of breast pain symptoms [1.29 (1.04, 1.59)]. Smokers were 3.41 (1.19, 9.77) times as likely to report any ≥3 symptoms compared to nonsmokers.

Conclusion

Several potentially modifiable factors, such as diet and stress, were positively associated with PMSx. Thus, we suggest that increasing women's awareness of healthy lifestyles, particularly diet and stress reduction, may help to reduce the occurrence of premenstrual symptoms.

Potential Disruption of Systemic Hormone Transport by Tobacco Alkaloids Using Computational Approaches

Tobacco/nicotine is one of the most toxic and addictive substances and continues to pose a significant threat to global public health. The harmful effects of smoking/nicotine affect every system in the human body. Nicotine has been associated with effects on endocrine homeostasis in humans such as the imbalance of gonadal steroid hormones, adrenal corticosteroid hormones, and thyroid hormones. The present study was conducted to characterize the structural binding interactions of nicotine and its three important metabolites, cotinine, trans-3'-hydroxycotinine, and 5'-hydroxycotinine, against circulatory hormone carrier proteins, i.e., sex-hormone-binding globulin (SHBG), corticosteroid-binding globulin (CBG), and thyroxine-binding globulin (TBG). Nicotine and its metabolites formed nonbonded contacts and/or hydrogen bonds with amino acid residues of the carrier proteins. For SHBG, Phe-67 and Met-139 were the most important amino acid residues for nicotine ligand binding showing the maximum number of interactions and maximum loss in ASA. For CBG, Trp-371 and Asn-264 were the most important amino acid residues, and for TBG, Ser-23, Leu-269, Lys-270, Asn-273, and Arg-381 were the most important amino acid residues. Most of the amino acid residues of carrier proteins interacting with nicotine ligands showed a commonality with the interacting residues for the native ligands of the proteins. Taken together, the results suggested that nicotine and its three metabolites competed with native ligands for binding to their carrier proteins. Thus, nicotine and its three metabolites may potentially interfere with the binding of testosterone, estradiol, cortisol, progesterone, thyroxine, and triiodothyronine to their carrier proteins and result in the disbalance of their transport and homeostasis in the blood circulation.

Factors associated with regularity and length of menstrual cycle: Korea Nurses’ Health Study

Background

Menstrual cycle characteristics are linked to reproductive function and long-term health outcomes. This study aimed to evaluate menstrual cycle patterns, characterized by regularity and length, and associated factors among women in the Korea Nurses’ Health Study.

Methods

A total of 9335 premenopausal women aged 22–45 years were included in this cross-sectional study. Regularity and length of menstrual cycles were self-reported, and their associations with reproductive, lifestyle, and occupational factors were examined using binomial and multinomial logistic regression models. Adjusted least-square means of menstrual distress, depressive symptoms, stress, fatigue, anxiety, and sleep problems were estimated according to menstrual cycle characteristics using generalized linear models.

Results

Twenty-one percent of nurses reported having irregular menstrual cycles (variability > 7 days). Ten percent, 64%, and 26% had menstrual cycle length of < 26, 26–31, and 32–50 days, respectively. Variability and length of cycles decreased with age and increased with age at menarche. Parous women showed low tendency of irregular cycles. Women with body mass index (BMI) > 25 kg/m² had higher odds of irregular (odds ratio [OR] 1.68; 95% confidence interval [CI] 1.40–2.03) and long cycles (OR 1.31; 95% CI 1.08–1.58) than those with BMI 18.5– < 23 kg/m². Irregular cycles were less common in women performing vigorous physical activity, but more common in those with prolonged standing or frequent heavy lifting at work. Frequent rotating night shift was associated with irregular cycles among nulliparous women. Levels of menstrual and premenstrual distress, depressive symptoms, perceived stress, physical and mental fatigue, anxiety, and sleep problems were higher in women with irregular cycles than in those with regular cycles (p < 0.001, each).

Conclusions

The study suggests that irregular and long menstrual cycles are associated with reproductive, lifestyle, and occupational factors; also with menstrual distress and perceived health status. Our findings contribute to a better understanding of potential risk factors for menstrual dysfunction, and thus, may help improve women’s health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01947-z.

Commonalities in Metabolic Reprogramming between Tobacco Use and Oral Cancer

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

Relationships of Tobacco Use and Kava Consumption to Sex-Associated Variation in Body Composition and Obesity Risk in Melanesian Adults From Vanuatu

Obesity prevalence has increased in low- and middle-income countries (LMICs) over the past several decades, with generally greater occurrence among adult females compared with males. Gendered variation in health behaviors, such as substance use, may play a role in how differences in obesity, body size, and composition manifest in association with sex. This study examines sex-moderated relationships of tobacco smoking and kava consumption with body composition and obesity among 301 Ni-Vanuatu (local self-identification meaning “of Vanuatu”) adults. Data collected included self-reported frequency of substance use as well as anthropometric measurements to assess body mass, composition, and obesity. Tobacco and kava use were associated with reduced measurements of body mass and adiposity in males, and kava use was associated with some elevated measurements of body mass and hip circumference in females. Kava use was also negatively associated with obesity based on waist-to-height ratio among males. These results have implications for evaluation and future research on substance control programs in this population.

Ginseng alleviates folliculogenesis disorders via induction of cell proliferation and downregulation of apoptotic markers in nicotine-treated mice

Background

Ginseng is a powerful phytoestrogen with high antioxidant properties.

Objective

This study aimed to evaluate the effect of Panax Ginseng (PG) on folliculogenesis, proliferation, and apoptosis in the ovary impaired by nicotine.

Methods

Forty adult mice were divided into five groups. Control, sham, and nicotine groups, and co-treated groups of nicotine and ginseng in doses of 0.5 and 1 g/kg. Folliculogenesis was assessed via histopathology and serum evaluation of estradiol, progesterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) by ELISA. Lipid peroxidation and antioxidant enzyme activities both in homogenate tissue and serum were assayed by colorimetric analysis. Apoptotic markers of cytochrome c (Cyt c), Bax, and Bcl-2 were evaluated by RT-PCR. Proliferative index was studied by the Ki-67 immunostaining procedure.

Results

In comparison to the control or sham groups, nicotine significantly reduced the levels of FSH, LH, and estradiol hormones. An insignificant reduction was observed in the progesterone hormone. Nicotine reduced all healthy follicle numbers, except primordial (P = 0.001). Malondialdehyde (MDA) was increased in tissue and serum in the nicotine group (P = 0.01). Serum catalase (CAT) and enzymatic activity of superoxide dismutase (SOD) both were reduced in tissue and the serum, in the nicotine group. Nicotine induced a reduction in the proliferative indexes of granulosa and theca cells in pre-antral and antral follicles (P = 0.001). However, its effect on the proliferative index of stroma cells was not significant. Apoptotic markers were elevated in the nicotine group (P = 0.001). Co-treatment with ginseng elevated all sex hormones, increased healthy follicles, and reduced tissue or serum lipid peroxidation, compared with the nicotine group (p < 0.05). Co-Treatment with ginseng also reduced the expression of apoptotic markers and increased the proliferative indexes in granulosa and theca cells in pre-antral and antral follicles and also in stroma cells, in comparison to the nicotine group (P = 0.001). All above-mentioned alterations following treatment with ginseng were remarkable, especially in the dose of 1 g/kg.

Conclusion

This study showed ginseng protects folliculogenesis via alteration of hypothalamic- pituitary–gonadal (HPG) axis, induction of proliferation in ovarian somatic cells, reduction of lipid peroxidation, and downregulation of apoptotic markers in the mouse ovary, treated with nicotine.

Joint effect of particulate matter and cigarette smoke on women's sex hormones

BACKGROUND

Although relationships between exposure to air pollution and reproductive health are broadly studied, mechanisms behind these phenomena are still unknown. The aim of the study was to assess whether exposure to particulate matter (PM10) and tobacco smoking have an impact on menstrual profiles of 17β-estradiol (E2) and progesterone (P) and the E2/P ratio.

METHODS

Levels of sex hormones were measured daily in saliva during the entire menstrual cycle among 132 healthy, urban women. Exposure to smoking (active or passive) was assessed by questionnaire, whilst exposure to PM10 with municipal monitoring data.

RESULTS

During the early luteal phase, profiles of E2 were elevated among women with higher versus lower exposure to PM10 (p = 0.02, post-hoc tests). Among those who were exposed versus unexposed to tobacco smoking, the levels of mean E2 measured during the entire cycle were higher (p = 0.02). The difference in mean E2 levels between the group of joint exposure (i.e. to high PM10 and passive or active smoking) versus the reference group (low PM10, no smoking) was statistically significant at p = 0.03 (18.4 vs. 12.4 pmol/l, respectively). The E2/P ratios were higher among women with higher versus lower exposure to PM10 and this difference was seen only in the early luteal phase (p = 0.01, exploratory post-hoc tests).

CONCLUSIONS

We found that PM10 and tobacco smoking affect ovarian hormones independently and do not interact with each other. Both exposures appear to have estrogenic effects even though women's susceptibility to these effects differs across the menstrual cycle. We propose that the hormonal mechanisms are involved in observed relationships between air pollution and smoking with women's reproductive health.

Premature menopause among women in India: Evidence from National Family Health Survey-IV

AIM

Women who experience premature menopause either due to biological or induced reasons have a longer duration of exposure to severe symptoms and adverse health consequences when compared to those who undergo menopause at later age. Despite the fact that premature menopause has a profound effect on the health of women, there has been limited study on this issue. Therefore, this study attempted to determine the prevalence and factors associated with premature menopause among 302 557 women aged 25-39 years in India.

METHODS

This study utilized secondary data from the fourth round of the National Family Health Survey-IV (NFHS-4), conducted during 2015-2016 in India. Descriptive statistics and multinomial logistic regression were used for statistical analyses of the data.

RESULTS

The results revealed that the prevalence of premature menopause in this sample of Indian women was 3.7%, out of which 2.1% of women had experienced natural premature menopause, whereas 1.7% had surgical premature menopause. The prevalence of premature menopause was highest in the southern region of India. Factors like age, education, wealth index, place of residence, smoking status, children ever born, age at first birth, use of hormonal contraception, sterilization, and body mass index were found to be associated with premature menopause in India.

CONCLUSION

A sizeable proportion of women in India are attaining menopause prematurely. Furthermore, the percentage and likelihood of experiencing premature menopause are relatively high among rural women, women with higher parity, early age at childbearing, and women who smoke.

Electronic Cigarettes and Fecundability: Results From a Prospective Preconception Cohort Study

Although electronic cigarette (e-cigarette) aerosol contains similar toxicants to combustible cigarettes, few studies have examined their influence on fecundability. We assessed the association between e-cigarette use and fecundability, overall and according to combustible cigarette smoking history, in a cohort of 4,586 North American women (aged 21-45 years) enrolled during 2017-2020 in Pregnancy Study Online, a Web-based prospective preconception study. Women reported current and former e-cigarette use on baseline and follow-up questionnaires, and they completed bimonthly follow-up questionnaires until self-reported pregnancy or censoring. Fecundability ratios and 95% confidence intervals were calculated using proportional probabilities models, controlling for potential confounders. Overall, 17% of women had ever used e-cigarettes and 4% were current users. Compared with never use of e-cigarettes, current e-cigarette use was associated with slightly lower fecundability (fecundability ratio = 0.84, 95% confidence interval (CI): 0.67, 1.06). Compared with current nonusers of e-cigarettes and combustible cigarettes, fecundability ratios were 0.83 (95% CI: 0.54, 1.29) for current dual users of e-cigarettes and combustible cigarettes, 0.91 (95% CI: 0.70, 1.18) for current e-cigarette users who were nonsmokers of combustible cigarettes, and 1.01 (95% CI: 0.85, 1.20) for nonusers of e-cigarettes who were current smokers of combustible cigarettes. Current e-cigarette use was associated with slightly reduced fecundability, but estimates of its independent and joint associations with combustible cigarette smoking were inconsistent and imprecise.

Effects of past environmental tobacco smoke exposure on the menstrual cycle and menstrual phase-related symptoms: A cross-sectional study

AIM

This study examined the effects of current and past environmental tobacco smoke exposure on the menstrual cycle and menstrual phase-related symptoms in nonsmoking Japanese women of child-bearing age.

METHODS

Of 5000 women who agreed to participate, 3935 were analyzed (932 smokers, 2326 nonsmokers, and 677 past smokers). Nonsmokers were divided into three groups based on smoking status and environmental tobacco smoke exposure: nonsmokers without exposure (n = 352), nonsmokers with past exposure (n = 1196) and nonsmokers with current exposure (n = 778). Participants completed a questionnaire on background characteristics, environmental tobacco smoke exposure (location and relationship to smokers), abnormal menstrual cycle, days of menstrual cycle and menstrual cycle-related symptoms experienced in the past 3 months (assessed by the Menstrual Distress Questionnaire).

RESULTS

Mean age was 29.7 ± 7.0 (20-44) years. Compared with nonsmokers without environmental tobacco smoke exposure, current smokers had the highest risk of an abnormal menstrual cycle (adjusted odds ratio [OR], 1.74 [1.194-2.545]), followed by nonsmokers with past exposure (adjusted OR, 1.70 [1.171-2.464]), past smokers (adjusted OR, 1.60 [1.081-2.366]) and nonsmokers with current environmental tobacco smoke exposure (adjusted OR, 1.49 [0.901-1.212]). Irrespective of environmental tobacco smoke exposure, current smokers reported significantly more severe premenstrual and menstrual symptoms than nonsmokers, and nonsmokers with past environmental tobacco smoke exposure had significantly more severe premenstrual and menstrual symptoms than nonsmokers without environmental tobacco smoke exposure.

CONCLUSION

Past environmental tobacco smoke exposure, especially during childhood or adolescence, might harm women's reproductive health when they reach reproductive age.

[Cannabis: Similarities and differences with tobacco]

Nicotine is the specific psychoactive substance of tobacco while tetrahydrocannabinol (THC) is the specific component of cannabis. The inhalation technique of cannabis is different from that of tobacco smoking: the volume of puffs is larger, inhalation is deeper, and pulmonary retention time is longer. Cannabis addiction is difficult to evaluate, both products often being smoked concomitantly. The principle physical side effects of cannabis affect organs and functions in a similar way to tobacco: pulmonary, cardiovascular, endocrine and stomatological. Gastrointestinal complications such as cannabinoid hyperemesis are specific to cannabis. Some psychological effects of THC may be acute (altered time and space perception, sensory disability, decreased vigilance, mood and dissociative disorders, hallucinations and delirium, impaired learning and memory, impaired cognitive and motor performance, panic attacks and anxiety) or chronic (lack of motivation, disorganisation of thoughts, increase in frequency and severity of schizophrenic crises). Cannabis can also be implicated in traffic and workplace accidents. Synthetic cannabinoids have increased psychotropic and somatic effects due to a greater affinity for brain cannabinoid receptors.

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.

Sex-based differences in inflammatory bowel diseases: a review

Sex-based differences in inflammatory bowel disease (IBD) pathogenesis, disease course, and response to therapy have been increasingly recognized, however, not fully understood. Experimental and translational models have been leveraged to investigate hypothesized mechanisms for these observed differences, including the potential modifying role of sex hormones and sex-dependent (epi)genetic and gut microbiome changes. The primary objective of this review is to comprehensively describe sex-based differences in IBD including epidemiology, pathogenesis, phenotypic differences, therapeutic response, and outcomes.

Trichostatin A alleviated ovarian tissue damage caused by cigarette smoke exposure

Cigarette smoke (CS) has a negative impact on women's health and fertility. Studies have shown that histone deacetylases 1 and 2 (HDAC1/2) were involved in oocyte development. However, the roles of HDAC1/2 in ovarian toxicity caused by CS exposure and the therapeutic potential of trichostatin A (TSA, a HDAC inhibitor) for ovarian tissue damage have not been investigated. In this study, Female C57BL/6 mice were exposed to CS from six cigarettes mixed with indoor air for 120 min (one cigarette for 20 min) using a whole-body mainstream smoke exposure system twice daily for 30 days. TSA (0.6 mg/kg body weight) was injected intraperitoneally into mice in the Control + TSA group and CS + TSA group every two days for 30 days. We found that exposure to CS resulted in ovarian tissue damage and HDAC1/2 over-expression. TSA alleviated the structural changes of ovarian tissue induced by smoking and prevented the activation of HDAC1/2. Exposure to CS caused autophagy inhibition and pyroptosis activation. TSA treatment restored the expression of autophagy-associated proteins and decreased the levels of pyroptosis-related proteins induced by CS exposure. The TSA effect may be mediated by inhibition of HDAC1/2 involved in autophagy and pyroptosis process.

N-acetylcysteine yields sex-specific efficacy for cue-induced reinstatement of nicotine seeking

Women report greater craving during certain phases of the menstrual cycle. As well, research indicates that pharmacotherapies for smoking may be less efficacious in women compared with men, which may be due to interactions with natural fluctuations in ovarian hormone levels. N-Acetylcysteine (NAC) is a glutamatergic compound that has shown some efficacy in treating substance use disorders and aids in the prevention of relapse. However, it is unclear whether NAC has sex-specific effectiveness for nicotine relapse treatment. Given that NAC has shown promise to reduce nicotine reinstatement in preclinical models using male rats, the exploration of potential sex differences in the efficacy of NAC is warranted. Using a rat model, we first investigated the ability of NAC treatment (100 mg/kg, ip) during nicotine withdrawal with extinction training to reduce cue-induced nicotine seeking in male and female rats. Next, we assessed whether NAC's effects were estrous cycle-dependent for female rats. Results show that following NAC treatment during extinction, reinstatement of nicotine seeking was significantly decreased in males but not females, indicating a sex-specific effect of NAC. Furthermore, for females, both vehicle- and NAC-treated groups significantly reinstated nicotine-seeking behavior compared with extinction, regardless of estrous cycle phase. These results suggest that NAC is inefficacious in reducing nicotine relapse in females regardless of estrous cycle phase at the dose evaluated here. These collective findings could have important clinical implications for use and efficacy of NAC as a pharmacotherapy for freely cycling women smokers.

Sex-based differences in the incidence of inflammatory bowel diseases-pooled analysis of population-based studies from the Asia-Pacific region

BACKGROUND

There appear to be differences in risk factor profiles for IBD between Asia-Pacific and Western populations, which might suggest idiosyncrasies in pathogenesis. Recently, sex-based differences in IBD according to the age of diagnosis have been described in Western populations.

AIM

To identify whether sex-based differences in IBD incidence similarly exist across the age spectrum for Asia-Pacific populations.

METHODS

We identified Asia-Pacific population-based cohorts where IBD incidence data stratified by sex were available for the full age spectrum. Cohorts were included only if IBD diagnoses were confirmed and validated. We calculated incidence rate ratios of Crohn's disease (CD) and ulcerative colitis (UC) according to age and compared differences between males and females using random-effects meta-analysis.

RESULTS

Among 567.8 million people from 11 Asia-Pacific countries/provinces/nations, we identified 10 553 incident CD cases (7060 males; 3493 females) and 16 946 incident UC cases (9754 males; 7192 females). Starting in early adolescence until age 50 years, there was a 36%-64% higher incidence of CD in males vs females (P < 0.001). UC incidence ranged from 20%-42% higher in males vs females in the age groups between 15 and 65 years (P < 0.05).

CONCLUSIONS

In a pooled analysis of population-based studies from the Asia-Pacific region, we found a male predominance of both CD and UC for the majority of the age spectrum from adolescence to middle/late-middle age. Additional studies are needed to clarify biological and nonbiological determinants of sex differences in IBD, which might be distinct between Asia-Pacific and Western populations.

Adolescent smoking: The relationship between cigarette consumption and BMI

Background

Studies relating cigarette smoking and body weight yield conflicting results. Weight-lowering effects in women and men have been associated with smoking, however, no effects on weight have been proven. This study examined the association between cigarette smoking and relative weight in adolescent males and females as they age into young adults.

Methods

Data from the National Longitudinal Survey of Youth—a nationally representative survey conducted annually—was used for this analysis. The sample consists of 4225 males and females observed annually from 1997 at age 12 to 17 through 2011 at age 27 to 31. Hierarchical generalized models (HGM) assess the impact of smoking on the likelihood of having higher BMI controlling for demographic, household and environmental impacts. The second estimation considers the possibility that smoking is endogenous and utilizes a multinomial instrument (IV) for smoking level.

Results

HGM models reveal a negative association between cigarette smoking and BMI for both males and females. Individuals who smoke more have lower BMI compared to infrequent or non-smokers. General health rating, region of residence and income were used instrument for smoking in a linear two-stage IV specification. The instrument is highly correlated with BMI and results mirror the HGM. Finally, models run on early, middle and advanced adolescents show that the relationship diminishes over time. The relationship between BMI and smoking decreases as females age but increases for males.

Conclusions

Empirical models confirm an association cigarette consumption and BMI in both males and females. This negative relationship varies with age. It is important to identify health risks—obesity—and modifiable risk factors—smoking—that contribute to health disparities among adolescents. However, the increase in one risky behavior leading to the decrease in the prevalence of the other, complicates the issue. The higher prevalence of frequent cigarette uses among both adolescents and young adults of lower BMI suggest that smoking could be used curb or suppress appetite.

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The weight impact of tobacco use by adolescents, unlike adults, has not been conclusively determined.

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This study examines the relationship between cigarette use and the body weight (BMI) of high school aged youth.

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Since smoking can be considered endogeneous in weight studies, smoking is instrumented in a two-stage process.

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Cigarette use is associated with higher BMI, but magnitudes vary by age.

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Models run on early, middle and older adolescents show that the relationship diminishes over time.

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The relationship between BMI and smoking decreases as females age but increases for males.

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Overweight and obese adolescents were more frequent tobacco users.

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Results suggest that electronic and conventional tobacco has similar BMI associations when used independently.

Sex-Based Differences in Incidence of Inflammatory Bowel Diseases-Pooled Analysis of Population-Based Studies From Western Countries

BACKGROUND & AIMS

Although the incidence of inflammatory bowel diseases (IBDs) varies with age, few studies have examined variations between the sexes. We therefore used population data from established cohorts to analyze sex differences in IBD incidence according to age at diagnosis.

METHODS

We identified population-based cohorts of patients with IBD for which incidence and age data were available (17 distinct cohorts from 16 regions of Europe, North America, Australia, and New Zealand). We collected data through December 2016 on 95,605 incident cases of Crohn's disease (CD) (42,831 male and 52,774 female) and 112,004 incident cases of ulcerative colitis (UC) (61,672 male and 50,332 female). We pooled incidence rate ratios of CD and UC for the combined cohort and compared differences according to sex using random effects meta-analysis.

RESULTS

Female patients had a lower risk of CD during childhood, until the age range of 10-14 years (incidence rate ratio, 0.70; 95% CI, 0.53-0.93), but they had a higher risk of CD thereafter, which was statistically significant for the age groups of 25-29 years and older than 35 years. The incidence of UC did not differ significantly for female vs male patients (except for the age group of 5-9 years) until age 45 years; thereafter, men had a significantly higher incidence of ulcerative colitis than women.

CONCLUSIONS

In a pooled analysis of population-based studies, we found age at IBD onset to vary with sex. Further studies are needed to investigate mechanisms of sex differences in IBD incidence.

The influence of smoking and cessation on the human reproductive hormonal balance

Smoking is the most widespread substance dependence in the world. Nicotine and some other components of the cigarette smoke cause various endocrine imbalances, and have negative effects on pituitary, thyroid, adrenal, testicular and ovarian functions. Here, we examined studies that describe the influence of smoking and smoking cessation on the male and female reproductive systems. We also focused on studies providing an account of differences in cessation success rates between men and women. In men, the most common effects associated with smoking are erectile dysfunction and decreasing spermiogram quality. Several groups have studied the effects of cigarette smoking on testosterone levels in men. However, the results have been conflicting. In women, nicotine has an anti-estrogen effect and increases the ratio of androgens to estrogens throughout life. Beside nicotine, other cigarette toxins also cause dysregulation of reproductive and hormonal system, and essentially influence the probability of a successful pregnancy not only in cases of assisted reproduction but also in healthy women. Tobacco addiction is one of the forms of addiction that are generally thought to be different for men and for women. Women are less successful than men in quitting smoking, and nicotine replacement therapy is less effective in female smokers. We also summarize recent studies that have indicated possible reasons.

Thyroid hormones and menstrual cycle function in a longitudinal cohort of premenopausal women

BACKGROUND

Previous studies have reported that hyperthyroid and hypothyroid women experience menstrual irregularities more often compared with euthyroid women, but reasons for this are not well-understood and studies on thyroid hormones among euthyroid women are lacking. In a prospective cohort study of euthyroid women, this study characterised the relationship between thyroid hormone concentrations and prospectively collected menstrual function outcomes.

METHODS

Between 2004-2014, 86 euthyroid premenopausal women not lactating or taking hormonal medications participated in a study measuring menstrual function. Serum thyroid hormones were measured before the menstrual function study began. Women then collected first morning urine voids and completed daily bleeding diaries every day for three cycles. Urinary oestrogen and progesterone metabolites (estrone 3-glucuronide (E₁ 3G) and pregnanediol 3-glucuronide (Pd3G)) and follicle-stimulating hormone were measured and adjusted for creatinine (Cr).

RESULTS

Total thyroxine (T₄ ) concentrations were positively associated with Pd3G and E₁ 3G. Women with higher (vs lower) T₄ had greater luteal phase maximum Pd3G (Pd3G = 11.7 μg/mg Cr for women with high T₄ vs Pd3G = 9.5 and 8.1 μg/mg Cr for women with medium and low T₄ , respectively) and greater follicular phase maximum E₁ 3G (E₁ 3G = 41.7 ng/mg Cr for women with high T₄ vs E₁ 3G = 34.3 and 33.7 ng/mg Cr for women with medium and low T₄ , respectively).

CONCLUSIONS

Circulating thyroid hormone concentrations were associated with subtle differences in menstrual cycle function outcomes, particularly sex steroid hormone levels in healthy women. Results contribute to the understanding of the relationship between thyroid function and the menstrual cycle, and may have implications for fertility and chronic disease.

Association between smoking and non-alcoholic fatty liver disease: A systematic review and meta-analysis

Background/aims

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases. Some risk factors are known to influence the development of non-alcoholic fatty liver disease, but the effect of tobacco smoking on the progression of non-alcoholic fatty liver disease is controversial. The main goal of this systematic review and meta-analysis is to investigate the association between smoking and non-alcoholic fatty liver disease.

Method

Electronic databases (PubMed, Scopus, and ISI Web of Science) were searched to find published articles on non-alcoholic fatty liver disease and smoking until December 2016. All relevant studies were screened by inclusion and exclusion criteria and compatible studies were chosen. The Newcastle-Ottawa Scale was used to assess the methodological quality of eligible articles. Subsequently, information was gathered based on the following: author, publication year, keywords, country, inclusion and exclusion criteria, main results, study design, conclusion, and confounder variables (age, body mass index, gender, ethnicity, and diabetes). Finally, analyses were performed using Comprehensive Meta-Analysis Software.

Results

Data were extracted from 20 observational studies (9 cross-sectional, 6 case-control, 4 cohort studies, and 1 retrospective cohort study). A significant association was observed between smoking and non-alcoholic fatty liver disease with a pooled odds ratio of 1.110 (95% confidence interval, 1.028-1.199), p-value = 0.008. The statistical heterogeneity was medium with an I2 of 40.012%, p-heterogeneity = 0.074. Also there was a significant relation between non-alcoholic fatty liver disease and passive smoking with a pooled odds ratio of 1.380 (95% confidence interval, 1.199-1.588; p-value = 0.001; I2 = 59.41; p-heterogeneity = 0.117).

Conclusion

Our meta-analysis demonstrated that smoking is significantly associated with non-alcoholic fatty liver disease. Further prospective studies exploring the underlying mechanisms of this association should be pursued. Also passive smoking increases the risk of non-alcoholic fatty liver disease about 1.38-fold. The effects of smoking cigarettes on active smokers (current smoker, former smoker, and total smoker) are less than passive smokers. Further studies are needed to compare the of effects of passive and active smoking on non-alcoholic fatty liver disease.

Associations of Demographic Factors and Tobacco Use With Progesterone and Estradiol During Pregnancy

OBJECTIVE

To evaluate the association of biochemically validated prenatal tobacco use with serum progesterone and estradiol in the second trimester of pregnancy, controlling for demographic and personal factors.

STUDY DESIGN

This secondary analysis of a multicenter longitudinal study included 114 women with singleton pregnancies. Multiple regression analysis assessed whether prenatal tobacco use was related to hormone levels during the second trimester, controlling for covariates (age, body mass index, and race or ethnicity, with gestational age added to subsequent models).

RESULT

In the initial regressions, tobacco users had significantly lower progesterone level compared with nonsmokers (p = .037), while estradiol was unrelated to prenatal tobacco use. Women with greater body mass index also had significantly lower progesterone (p = .028), but body mass index was unrelated to estradiol. With gestational age as an additional covariate, prenatal tobacco use was no longer a significant predictor of progesterone, but both body mass index and gestational age were significant (F = 10.6, p < .001, R 2 = 0.35). For estradiol, the overall regression of estradiol on age, body mass index, and race or ethnicity was not significant (F = 1.2, p = .31). With gestational age added to the model, the overall model was significant (F = 7.2, p < .001, R 2 = 0.27).

CONCLUSION

This study provides additional evidence that prenatal tobacco use may influence lower serum progesterone during the second trimester. This is of particular concern given the link between depressed progesterone activity and risk for preterm birth.

Age at Pubertal Onset in Girls and Tobacco Smoke Exposure During Pre- and Postnatal Susceptibility Windows

BACKGROUND

Tobacco smoke contains known hormonally active chemicals and reproductive toxicants. Several studies have examined prenatal maternal smoking and offspring age at menarche, but few examined earlier pubertal markers, nor accounted for exposure during childhood. Our objective was to examine pre- and postnatal smoke exposure in relation to timing of early pubertal events.

METHODS

An ethnically diverse cohort of 1239 girls was enrolled at age 6-8 years old for a longitudinal study of puberty at three US sites. Girls participated in annual or semi-annual exams to measure anthropometry and Tanner breast and pubic hair stages. Prenatal and current tobacco smoke exposures, as well as covariates, were obtained from parent questionnaire. Cotinine was measured in urine collected at enrollment. Using accelerated failure time models, we calculated adjusted time ratios for age at pubertal onset (maturation stages 2 or higher) and smoke exposure.

RESULTS

Girls with higher prenatal (≥5 cigarettes per day) or secondhand smoke exposure had earlier pubic hair development than unexposed (adjusted time ratio: 0.92 [95% CI = 0.87, 0.97] and 0.94 [95% CI = 0.90, 0.97], respectively). Including both exposures in the same model yielded similar associations. Higher urinary cotinine quartiles were associated with younger age at breast and pubic hair onset in unadjusted models, but not after adjustment.

CONCLUSIONS

Greater prenatal and childhood secondhand smoke exposure were associated with earlier onset of pubic hair, but not breast, development. These exposures represent modifiable risk factors for early pubertal development that should be considered for addition to the extensive list of adverse effects from tobacco smoke.

Cigarette Smoking and Risk of Incident Rosacea in Women

The relationship between smoking and rosacea is poorly understood. We aimed to conduct the first cohort study to determine the association between smoking and risk of incident rosacea. We included 95,809 women from Nurses' Health Study II (1991-2005). Information on smoking was collected biennially during follow-up. Information on history of clinician-diagnosed rosacea and year of diagnosis was collected in 2005. We used Cox proportional hazards models to estimate age- and multivariable-adjusted hazard ratios and 95% confidence intervals for the association between different measures of smoking and risk of rosacea. During follow-up, we identified 5,462 incident cases of rosacea. Compared with never smoking, we observed an increased risk of rosacea associated with past smoking (multivariable-adjusted hazard ratio = 1.09, 95% confidence interval: 1.03, 1.16) but a decreased risk associated with current smoking (hazard ratio = 0.65, 95% confidence interval: 0.58, 0.72). We further found that increasing pack-years of smoking was associated with an elevated risk of rosacea among past smokers (P for trend = 0.003) and with a decreased risk of rosacea among current smokers (P for trend < 0.0001). The risk of rosacea was significantly increased within 3-9 years since smoking cessation, and the significant association persisted among past smokers who had quit over 30 years before.

Risk factors for cryptorchidism

Undescended testis - known as cryptorchidism - is one of the most common congenital abnormalities observed in boys, and is one of the few known risk factors for testicular cancer. The key factors that contribute to the occurrence of cryptorchidism remain elusive. Testicular descent is thought to occur during two hormonally-controlled phases in fetal development - between 8-15 weeks (the first phase of decent) and 25-35 weeks gestation (the second phase of descent); the failure of a testis to descend permanently is probably caused by disruptions to one or both of these phases, but the causes and mechanisms of such disruptions are still unclear. A broad range of putative risk factors have been evaluated in relation to the development of cryptorchidism but their plausibility is still in question. Consistent evidence of an association with cryptorchidism exists for only a few factors, and in those cases in which evidence seems unequivocal the factor is likely to be a surrogate for the true causal exposure. The relative importance of each risk factor could vary considerably between mother-son pairs depending on an array of genetic, maternal, placental and fetal factors - all of which could vary between regions. Thus, the role of causative factors in aetiology of cryptorchidism requires further research.

Association between single nucleotide polymorphisms in the antioxidant genes CAT, GR and SOD1, erythrocyte enzyme activities, dietary and life style factors and breast cancer risk in a Danish, prospective cohort study

Exposure to estrogens and alcohol consumption - the two only well-established risk factors for breast cancer - are capable of causing oxidative stress, which has been linked to progression of breast cancer. Here, five functional polymorphisms in the antioxidant genes SOD1, CAT and GSR were investigated in 703 breast cancer case-control pairs in the Danish, prospective “Diet, Cancer and Health” cohort together with gene-environment interactions between the polymorphisms, enzyme activities and intake of fruits and vegetables, alcohol and smoking in relation to breast cancer risk. Our results showed that genetically determined variations in the antioxidant enzyme activities of SOD1, CAT and GSR were not associated with risk of breast cancer per se. However, intake of alcohol, fruit and vegetables, and smoking status interacted with some of the polymorphisms in relation to breast cancer risk. Four polymorphisms were strongly associated with enzyme activity, but there was no interaction between any of the studied environmental factors and the polymorphisms in relation to enzyme activity. Additionally, single measurement of enzyme activity at entry to the cohort was not associated with risk of breast cancer. Our results therefore suggest that the antioxidant enzyme activities studied here are not major determinants of breast cancer risk.

Preconception health behaviours: A scoping review

Preconception health refers to the health of males and females at any point in time prior to a potential pregnancy. A goal of preconception health research is to use preventive behaviour and healthcare to optimize the health of future offspring that result from both planned and unplanned pregnancies. This paper briefly reviews evidence of the importance of various preconception health behaviours, and examines the extent to which specific preconception health behaviours have been included in recent studies of such knowledge, behaviours, and intentions. To describe this recent research in highly developed countries, a scoping review of the literature was completed of studies published within the past seven years. A total of 94 studies on preconception health were identified and reviewed: (a) 15 examined knowledge and attitudes, (b) 68 studied behaviours, (c) 18 examined interventions designed to improve knowledge or behaviour, and (d) no studies examined intentions to engage in preconception health behaviours. Over 40% of studies examining preconception health behaviour focussed exclusively on folic acid. Overall, folic acid, alcohol, and cigarettes have consistently been topics of focus, while exposure to harmful environmental substances, stress, and sleep have been largely neglected. Despite strong evidence for the importance of men's health during the preconception period, only 11% of all studies included male participants. Based on existing gaps in the research, recommendations are provided, such as including men in future research, assessing a wider variety of behaviours, consideration of behavioural intentions, and consideration of the relationships between preconception health knowledge, intentions, and behaviour.

Associations between urinary biomarkers of polycyclic aromatic hydrocarbon exposure and reproductive function during menstrual cycles in women

Essentially all women are exposed to polycyclic aromatic hydrocarbons (PAHs), formed during incomplete combustion of organic materials, including fossil fuels, wood, foods, and tobacco. PAHs are ovarian toxicants in rodents, and cigarette smoking is associated with reproductive abnormalities in women. Biomonitoring of hydroxylated PAH (OH-PAH) metabolites in urine provides an integrated measure of exposure to PAHs via multiple routes and has been used to characterize exposure to PAHs in humans. We hypothesized that concentrations of OH-PAHs in urine are associated with reproductive function in women. We recruited women 18-44years old, living in Orange County, California to conduct daily measurement of urinary luteinizing hormone (LH) and estrone 3-glucuronide (E₁3G) using a microelectronic fertility monitor for multiple menstrual cycles; these data were used to calculate endocrine endpoints. Participants also collected urine samples on cycle day 10 for measurement of nine OH-PAHs. Models were constructed for eight endpoints using a Bayesian mixed modeling approach with subject-specific random effects allowing each participant to act as a baseline for her set of measurements. We observed associations between individual OH-PAH concentrations and follicular phase length, follicular phase LH and E₁3G concentrations, preovulatory LH surge concentrations, and periovulatory E₁3G slope and concentration. We have demonstrated the feasibility of using urinary reproductive hormone data obtained via fertility monitors to calculate endocrine endpoints for epidemiological studies of ovarian function during multiple menstrual cycles. The results show that environmental exposure to PAHs is associated with changes in endocrine markers of ovarian function in women in a PAH-specific manner.

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.

Knowledge about and sources of smoking-related knowledge, and influencing factors among male urban secondary school students in Chongqing, China

Objectives

This study examined smoking-related knowledge, sources of smoking-related knowledge and its influencing factor among male urban secondary school students.

Methods

We conducted a cross-sectional survey, using a self-administered questionnaire, among 1297 male secondary school students in municipal areas of Chongqing, China.

Results

Non-smokers had a better knowledge of smoking hazards than smokers. Less than 20% of students knew that smoking can cause heart disease, peptic ulcer, and cerebral stroke. Sources of smoking-related knowledge differed between smokers and non-smokers, respectively: TV (76.5 vs. 76.7%), teacher (70.1 vs. 62.4%), social network (66.6 vs. 73.1%), parents (57.0 vs. 59.2%), newspaper (55.4 vs. 61.6%), and friends (37.7 vs. 33.9%). Non-smokers’ hobbies of reading were significantly higher than smokers’ (χ² = 11.5845, p = 0.0007). Smokers’ hobbies of online games (χ² = 14.9106, p = 0.0001), and sports (χ² = 4.8609, p = 0.0275) were significantly higher than non-smokers’. Generalized estimating equations (GEE) found that students whose both father and mother smoke were unable to receive tobacco-related knowledge. GEE also found that students in high school, with affluent family economic condition and with an opposing attitude towards father smoking possessed a better smoking-related knowledge. However, male students with disagreement or neutral attitude towards friends smoking were negatively associated with the knowledge of smoking hazards.

Conclusions

The findings of the present study suggest that a significant proportion of male secondary school students in urban Chongqing lack specific knowledge about smoking-related diseases. Targeted educational programs for secondary school students in China are needed to promote tobacco control and tobacco use reduction and cessation among students.

Detrimental Effects of Higher Body Mass Index and Smoking Habits on Menstrual Cycles in Korean Women

BACKGROUND

Alteration of menstrual cycle by individual lifestyles and unfavorable habits may cause menstrual irregularity. We aimed to investigate the relationship between lifestyle factors and menstrual irregularity in Korean women using data from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES) 2010-2012.

MATERIALS AND METHODS

This cross-sectional study included 3779 nondiabetic Korean women aged 19-49 years who did not take any oral contraceptives or sex hormonal compounds. We examined the association of menstrual irregularity with age, body mass index (BMI), drinking experience, and smoking habits.

RESULTS

Age, Asian BMI, marriage status, age at menarche, and smoking habits were significantly associated with menstrual cycle irregularity (p < 0.01). The prevalence of menstrual irregularity was significantly increased at younger ages: 18.4%, 10.3%, and 10.5% at 19-29, 30-39, and 40-49 years, respectively. Moreover, obesity groups, defined as per Asian BMI using modified WHO criteria, were strongly associated with menstrual irregularity. BMI 25.0-29.9 [obesity class I] (adjusted odds ratios [OR], 1.94; 95% confidence intervals [CI], 1.37-2.74) and ≥30.0 [obesity class II] (adjusted OR, 2.18; 95% CI, 1.22-3.91) presented significantly higher risk of menstrual irregularity compared with BMI 18.5-22.9 [normal weight]. Multivariable analysis revealed that high BMI in younger women aged 19-29 years (p < 0.001) and smoking habits in middle-aged women aged 30-39 years (p < 0.005) significantly predicted menstrual irregularity.

CONCLUSION

This study substantiated that menstrual irregularity was closely associated with higher BMI and smoking habits in nondiabetic Korean women. Weight loss and smoking cessation should be recommended to promote women's reproductive health.

A comparative evaluation of self-report and biological measures of cigarette use in nondaily smokers

A large subset of individuals who smoke cigarettes do not smoke regularly, but the assessments used to collect data on cigarette consumption in nondaily smokers have not been rigorously evaluated. The current study examined several self-report and biomarker approaches to the assessment of cigarette use in a sample of nondaily smokers (n = 176). Participants were randomly assigned to a daily monitoring condition (n = 89), requiring a daily report of the number of cigarettes smoked in the previous 24 hours, or a no monitoring condition (n = 87). Number of cigarettes smoked over the first 28 days of the study was assessed using 2 quantity frequency measures, a graduated frequency measure, and a timeline follow back (TLFB) interview at the Session 5 study visit. Hair nicotine (NIC), hair cotinine (COT), and expired-air carbon monoxide (CO) were collected from each participant. Total cigarettes reported via daily report were strongly correlated with all Session 5 measures of total cigarettes, but were most strongly associated with TLFB total cigarettes. Collapsed CO across 5 sessions was the biomarker most strongly correlated with daily report total cigarettes. The results support the use of daily report and TLFB methods of assessing cigarette use in nondaily smokers. Results also support the use of CO as appropriate biological markers of exposure in nondaily smokers, and point to some limitations in the use of hair biomarkers in this population. (PsycINFO Database Record

Smoking, alcohol and caffeine in relation to two hormonal indicators of ovarian age during the reproductive years

OBJECTIVE

To examine whether or not cigarette smoking, alcohol and caffeine intake are related to two indicators of ovarian age-anti-Müllerian hormone (AMH) and follicle stimulating hormone (FSH).

STUDY DESIGN

Cross-sectional study of 477 women with a recent index spontaneous abortion (SA) (105 trisomic, 93 non-trisomic) or livebirth (LB) (279) with hormones measured on days 2-4 of an apparently normal menstrual cycle after the index pregnancy.

RESULTS

Current smoking is associated with about a 15% increase in median FSH (β for ln(FSH)=0.14, 95% CI 0.03,0.25). It is not significantly related to AMH (β for ln(AMH)=-0.25, 95% CI -0.56,0.06). Neither alcohol 2-7days per week nor caffeine 122-<553mg per day is independently related to AMH or FSH.

CONCLUSIONS

The observation that current smoking is associated with FSH, but not with AMH, suggests that current smoking either impairs the development of antral follicles or dysregulates the hypothalamic-pituitary-ovarian axis. The absence of an association with AMH argues against mechanisms related to accelerated follicle atresia.

Predictors of coronary artery disease in middle-aged Taiwanese women at premenopause, postmenopause and after undergoing hysterectomy

AIMS AND OBJECTIVES

To examine the predictors of coronary artery disease among middle-aged women at various menopausal statuses.

BACKGROUND

Few studies have explored coronary artery disease predictors among middle-aged women at various menopausal statuses, particularly with the inclusion of women who underwent a hysterectomy.

DESIGN

A cross-sectional design was adopted.

METHODS

Two hundred and twenty-five middle-aged women who were waiting for catheterisation examinations because of possible coronary artery disease were selected. These patients were divided into premenopausal (n = 41), postmenopausal (n = 143) and women who had undergone a hysterectomy groups (n = 41). The differences in the risk factors for coronary artery disease between patients with coronary artery disease (catheterisation results showing stenosis of >50% in at least one major coronary artery) and those without coronary artery disease in the three groups were compared.

RESULTS

The participants were aged 56·8 ± 5·9 years. In the premenopausal group, the odds of coronary artery disease among ever or current smokers was 8·46 times the odds of coronary artery disease for the never smokers. In the postmenopausal group, the odds of coronary artery disease among diabetes patients was 2·89 times the odds of coronary artery disease for those without diabetes. Each additional point on the Chinese Beck Depression Inventory-II increased the risk of coronary artery disease by 5%. In the hysterectomy group, each additional increase in 1 mmHg in systolic blood pressure increased the risk of coronary artery disease by 4%.

CONCLUSIONS

Smoking, diabetes, depression and systolic blood pressure are predictors of coronary artery disease in middle-aged women at premenopause, postmenopause and after undergoing hysterectomy respectively.

RELEVANCE TO CLINICAL PRACTICE

These results are beneficial for middle-aged women at various menopausal stages to effectively implement prevention of coronary artery disease. These findings were among women being evaluated for possible coronary artery disease, we suggest the need for further study in lager, longitudinal studies.

Interaction of smoking and obesity susceptibility loci on adolescent BMI: The National Longitudinal Study of Adolescent to Adult Health

BACKGROUND

Adolescence is a sensitive period for weight gain and risky health behaviors, such as smoking. Genome-wide association studies (GWAS) have identified loci contributing to adult body mass index (BMI). Evidence suggests that many of these loci have a larger influence on adolescent BMI. However, few studies have examined interactions between smoking and obesity susceptibility loci on BMI. This study investigates the interaction of current smoking and established BMI SNPs on adolescent BMI. Using data from the National Longitudinal Study of Adolescent to Adult Health, a nationally-representative, prospective cohort of the US school-based population in grades 7 to 12 (12-20 years of age) in 1994-95 who have been followed into adulthood (Wave II 1996; ages 12-21, Wave III; ages 18-27), we assessed (in 2014) interactions of 40 BMI-related SNPs and smoking status with percent of the CDC/NCHS 2000 median BMI (%MBMI) in European Americans (n = 5075), African Americans (n = 1744) and Hispanic Americans (n = 1294).

RESULTS

Two SNPs showed nominal significance for interaction (p < 0.05) between smoking and genotype with %MBMI in European Americans (EA) (rs2112347 (POC5): β = 1.98 (0.06, 3.90), p = 0.04 and near rs571312 (MC4R): β 2.15 (-0.03, 4.33) p = 0.05); and one SNP showed a significant interaction effect after stringent correction for multiple testing in Hispanic Americans (HA) (rs1514175 (TNNI3K): β 8.46 (4.32, 12.60), p = 5.9E-05). Stratifying by sex, these interactions suggest a stronger effect in female smokers.

CONCLUSIONS

Our study highlights potentially important sex differences in obesity risk by smoking status in adolescents, with those who may be most likely to initiate smoking (i.e., adolescent females), being at greatest risk for exacerbating genetic obesity susceptibility.

The impact of lifestyle modifications, diet, and vitamin supplementation on natural fertility

BACKGROUND

Infertility is a relatively common condition. When patients are confronted with this diagnosis, there are medical, psychological, and financial sequelae. Patients often wonder if there is anything they can do to optimize their natural fertility or increase the effectiveness of infertility treatments.

FINDINGS

If there is a clear impact on fertility, such as with smoking and alcohol, cessation should be advised. Similarly, weight loss should be recommended if the BMI is in the overweight and obese category, and weight gain should be recommended for an underweight BMI. The evidence surrounding other lifestyle modifications is less clear. There are conflicting data regarding an optimal fertility diet and consumption of vitamins and supplements. Antioxidants seem to improve semen parameters in men, but the effect on female fertility is less clear. If conflicting evidence exists, such as with caffeine consumption or exercise, moderation should be emphasized. Finally, the diagnosis of infertility and subsequent fertility treatments are stressful for both partners. The psychological aspects should not be ignored and methods such as yoga and cognitive behavioral therapy may be beneficial.

CONCLUSION

Continued research will determine the optimal lifestyle modifications to achieve pregnancy.

In utero exposure to cigarette smoking, environmental tobacco smoke and reproductive hormones in US girls approaching puberty

BACKGROUND/AIMS

Evidence is unclear whether prenatal smoking affects age at menarche and pubertal development, and its impact upon hormones has not been well studied. We aim to identify potential pathways through which prenatal smoking and environmental tobacco smoke (ETS) affect reproductive hormones in girls approaching puberty.

METHODS

We examined the association between prenatal smoking, current ETS and luteinizing hormone (LH) and inhibin B (InB) in 6- to 11-year-old girls in the 3rd National Health and Nutrition Examination Survey, 1988-1994. Parents/guardians completed interviewer-assisted questionnaires on health and demographics at the time of physical examination. Residual blood samples were analyzed for reproductive hormones in 2008.

RESULTS

Of 660 girls, 19 and 39% were exposed to prenatal smoke and current ETS, respectively. Accounting for multiple pathways in structural equation models, prenatally exposed girls had significantly lower LH (β = -0.205 log-mIU/ml, p < 0.0001) and InB (β = -0.162, log-pg/ml, p < 0.0001). Prenatal smoking also influenced LH positively and InB negatively indirectly through BMI-for-age. ETS was positively associated with LH, but not with InB.

CONCLUSION

Exposure to maternal smoking may disrupt reproductive development manifesting in altered hormone levels near puberty.

[Menstrual cycle length and source of its variation in female university students majoring in nursing sciences]

OBJECTIVES

To acquire fundamental knowledge on menstrual cycle and its intraindividual variation in healthy Japanese female students and their association with biological attributes, lifestyle and food habit.

METHODS

We asked female students of a nursing school to keep a diary of their menstruation over 5 consecutive months and to fill a questionnaire on their biological attributes, lifestyle and consumption frequency of some food items during the period from November 2012 to January 2014.

RESULTS

The mean±standard deviation (SD) of cycle lengths of 180 women (20.4±0.9 yrs) was 34.2±10.5 days. Of these 180 women, 141 had a cycle length within the normal range (25-38 days) while 10 had a shorter cycle and 20 had a longer cycle. The intraindividual variations of the cycle, defined as "range" (difference between the longest and shortest cycles of an individual) and "SD" (SD of mean of multiple lengths within an individual), were 11.4±10.3 and 7.9±11.8 days, respectively. Of 177 women, 73 and 109 had normal range and SD (≤6 days), respectively. The mean age of women with long cycles was older than that of women with short cycle (Kruscal-Wallis test, p<0.05), and women with greater intraindividual variations were older than those with small variations (U-test, p<0.05). Subjects with menstrual pain had greater "SD" than did those without pain (Chi-square test, p<0.05). Neither lifestyle nor food habit was associated with the length and intraindividual variations of the menstrual cycle.

CONCLUSIONS

The present results provided fundamental knowledge on the length and intraindividual variations of the menstrual cycle and the sources of these variations in female Japanese university students.

How Smoking Cessation Influence Hormonal Levels in Postmenopausal Women?

Smoking represents the most widespread substance dependence in the world. Nicotine alters women hormonal homeostasis. Women smokers have higher testosterone and lower estradiol levels throughout life compared to non-smokers. We monitored the effect of smoking discontinuation on steroid spectrum with 25 postmenopausal women smokers. They had been examined before discontinuation of smoking and after 6, 12, 24 and 48 weeks of abstinence. Blood was collected to determine steroid spectrum (measured by GC-MS), luteinizing hormone, follicle stimulating hormone and sex hormone binding globulin (measured by IRMA). Repeated measures ANOVA model was used for evaluation of the data. In postmenopausal women, an increase in testosterone, dihydrotestosterone, dehydroepiandrosterone and other androgens occurred. Neither nicotine replacement therapy nor weight changes nor age play a role in androgen level increase. The higher androgens levels correlated with failure in smoking cessation. Women smokers have higher androgen levels, which might play a role in smoking dependence development. Women successful in smoking cessation, compared to the non-successful ones, have lower androgen levels initially and also after smoking discontinuation.