Early Menarche and Risk of Metabolic Syndrome: A Systematic Review and Meta-Analysis

Lifestyle Factors Influencing Metabolic Syndrome after Adjusting for Socioeconomic Status and Female Reproductive Health Indicators: A National Representative Survey in Korean Pre- and Postmenopausal Women

Metabolic syndrome (MetS) is increasing markedly among postmenopausal women. Although studies suggest multiple risk factors for its development, few have investigated changes in socioeconomic status (SES), female reproductive health indicators (menarche age, experience of pregnancy, delivery, breastfeeding, and postmenopausal status), and lifestyle factors. This study investigated lifestyle factors affecting MetS prevalence among pre- and post-menopausal women after adjusting for SES and female reproductive health indicators. Data from the Korea National Health and Nutrition Examination Survey VII (2016-2018) on 2856 pre- and postmenopausal women aged 40-59 years were analyzed. Differences in SES (e.g., age, education, and household income), female reproductive health indicators (e.g., age of menarche and menopause), and lifestyle (e.g., total calorie intake, fats, and proteins, percentage of energy from carbohydrates, fats, and proteins, smoking, physical activity, and obesity) between MetS and non-MetS groups were calculated by performing χ2 or t-tests. Consequently, current smoking, physical inactivity, overweight, and obesity were significantly associated with increased MetS after adjusting for SES and female reproductive health indicators using logistic regression analysis. Hence, health policies and programs focusing on modifiable MetS risk factors-encouraging healthy eating habits, smoking cessation, and regular exercise-must be formulated to prevent the development of MetS in pre- and postmenopausal women.

Trends in the prevalence of obesity, overweight, and thinness among schoolchildren aged 7-14 years from southern Brazil (2002-2019)

OBJECTIVE

To analyze the obesity, overweight, and thinness trends among Brazilian schoolchildren by sex, age group, and type of school according to World Health Organization (WHO) and International Obesity Task Force (IOTF) criteria.

METHODS

We conducted four surveys between 2002 and 2018/19 involving schoolchildren aged 7-14 years from a state capital in southern Brazil. Weight status was classified using both WHO and IOTF criteria.

RESULTS

In the total sample, obesity prevalence based on the IOTF and the WHO criteria were 72% and 44% higher in 2018/19 compared with 2002, respectively. Over the whole period, the obesity prevalence increased among children (WHO: 10.1% vs. 14.1%; IOTF: 5.0% vs. 8.3%), and those from public schools (WHO: 10.5% vs. 16.4%; IOTF: 5.6% vs. 10.1%). There was no significant reduction in thinness prevalence over the analyzed period.

CONCLUSION

Obesity prevalence remains on an upward trend in a state capital in southern Brazil, especially among children from public schools. A higher prevalence of overweight and obesity was observed using the WHO criteria compared with IOTF criteria.

Early menarche and other endocrine disrupting effects of per- and polyfluoroalkyl substances (PFAS) in adolescents from Northern Norway. The Fit Futures study

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) comprise a large group of chemicals that are ubiquitous in the environment and include recognized persistent organic pollutants. The aim of this cross-sectional study was to investigate possible endocrine disrupting effects of different PFAS in adolescents.

METHODS

Serum concentrations of PFAS, thyroid, parathyroid and steroid hormones were measured in 921 adolescents aged 15-19 years in the Fit Futures study, Northern Norway. The questionnaire included data on self-reported age at menarche and puberty development score (PDS). Multiple linear and logistic regression analyses and principle component analyses (PCA) were used to assess associations of PFAS with hormones concentrations and puberty indices.

RESULTS

In girls, total PFAS (∑PFAS), perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoate (PFNA), perfluorodecanoate (PFDA) were positively associated with dehydroepiandrosterone sulfate (DHEAS) and negatively associated with 11-deoxycorticosterone (11-DOC)/DHEAS ratio. In boys, the associations with 11-DOC/DHEAS ratio were positive for ∑PFAS, perfluoroheptanoate (PFHpA), perfluoroheptane sulfonate (PFHpS), PFOA, and PFOS. Perfluoroundecanoate (PFUnDA) was negatively associated with free thyroxine (fT4) and free triiodothyronine (fT3) in boys. PFNA and PFDA were also negatively associated with fT3 in boys. Serum parathyroid hormone concentration (PTH) was negatively associated with ∑PFAS and perfluorohexane sulfonate (PFHxS) in girls, and with PFOS in boys. PFDA and PFUnDA were positively associated with early menarche, while ∑PFAS and PFOA were positively associated with PDS in boys. No associations of PFAS with serum testosterone, follicle-stimulating hormone, or luteinizing hormone were found in either sex. In girls, PFOA was positively associated with free testosterone index (FTI). In boys, PFOA was positively associated with androstendione and 17-OH-progesterone, while PFHpA was positively associated with estradiol.

CONCLUSIONS

Serum concentrations of several PFAS were associated with parathyroid and steroid hormones in both sexes, and with thyroid hormones in boys, as well as with early menarche in girls and higher PDS in boys.

The J shaped association of age at menarche and cardiovascular events: systematic review and meta-analysis

This study aimed to evaluate the association between age at menarche and cardiovascular (CV) events through a systematic review and meta-analysis of observational studies. A comprehensive literature search covering studies published from January 1, 2000, to October 31, 2023, was conducted in PubMed, MEDLINE, Embase, and Scopus. Twenty-nine observational studies involving 4,931,160 adult women aged 18 years or older were included. The meta-analysis revealed a J-shaped association between age at menarche and CV events. Individuals with menarche at 12-13 years exhibited the lowest risk, while those with younger (≤ 11 years) or older ages (14-15 years and ≥ 16 years) showed an increased risk. Notably, individuals with age at menarche of 16 years and older had the highest risk of CV events. The pooled odds of CV mortality in age at menarche categories 14-15 years and ≥ 16 years were 37% (OR: 1.37, 95% CI 1.14-1.64, I2: 76.9%) and 64% (OR: 1.64, 95% CI 1.20-2.24, I2: 87%) higher than referent age at menarche 12-13 years. No statistically significant difference was found in CV mortality risk between individuals with age at menarche ≤ 11 years and those with age at menarche 12-13 years. The ORs for coronary heart disease were significantly higher for age at menarche ≥ 16 years (35% increase), while no significant difference was found for age at menarche ≤ 11 years or 14-15 years compared to age at menarche 12-13 years. Regarding stroke, the ORs for age at menarche ≤ 11, 14-15, and ≥ 16 years were significantly higher (7%, 24%, and 94% increase, respectively) compared to age at menarche 12-13 years. Dose-response meta-analysis and one-stage random-effect cubic spline models confirmed the J-shaped risk pattern. Meta-regression indicated that age and BMI were not significant sources of heterogeneity. Sensitivity analyses and the absence of publication bias further supported the robustness of the findings. This study concludes that age at menarche is independently associated with CV events, with a J-shaped pattern. The findings underscore the significance of considering menarche age as an independent risk factor for CV events. Further research is warranted to validate these findings and explore potential underlying mechanisms.

Separate and combined effects of famine exposure and menarche age on metabolic syndrome among the elderly: a cross-sectional study in China

BACKGROUND

Epidemiological studies have revealed multiple risk factors for metabolic syndrome. However, there are no consistent findings on the association between famine exposure, age at menarche, and the prevalence of metabolic syndrome. This cross-sectional study aimed to reveal the individual and combined effects of famine exposure and age at menarche on the prevalence of metabolic syndrome among elderly women.

METHODS

Four thousand seven hundred seventy participants between 60 and 93 years of age were selected from the China Health and Retirement Longitudinal Study. Statistical differences between the baseline characteristics of famine exposure, age at menarche, and metabolic syndrome were evaluated using the t-test, F-test, and Chi-square test. Three multivariable-adjusted logistic regression models were used to test the association between famine exposure, age of menarche, and the odds ratio of metabolic syndrome.

RESULTS

Two thousand one hundred ninety-eight (46.08%) participants had metabolic syndrome, while 2572 (53.92%) participants did not. Furthermore, 3068 (64.32%) women reported onset of menarche under 15 years of age, while 1702 (35.68%) women reported onset of menarche above 16 years of age. Regarding the separate association of famine exposure and age of menarche with metabolic syndrome, in model three, the adolescence/adulthood famine exposure group vs. no famine exposure group odds ratio was 2.45 (95% CI 2.02, 2.97), and the older than 16 years vs. younger than 15 years group odds ratio was 1.23 (95% CI 1.09, 1.39), which was the highest odds ratio among the three models. Regarding the combined association of famine exposure and age of menarche with metabolic syndrome, in model three, among the age of menarche ≤ 15 years group, the adolescence/adulthood famine exposure vs. no famine exposure group odds ratio was 2.45 (95% CI: 1.91, 3.14); among the menarche age ≥ 16 years group, the adolescence/adulthood famine exposure stages vs. exposed group odds ratio was 3.27 (95% CI: 2.44, 4.38), which was the highest odds ratio among the three models.

CONCLUSION

These findings suggested that famine exposure and age at menarche, either separately or in combination, were positively associated with the prevalence of metabolic syndrome among older women.

Impact of puberty, sex determinants and chronic inflammation on cardiovascular risk in young people

Worrying trends of increased cardiovascular disease (CVD) risk in children, adolescents and young people in the Modern Era have channelled research and public health strategies to tackle this growing epidemic. However, there are still controversies related to the dynamic of the impact of sex, age and puberty on this risk and on cardiovascular health outcomes later in life. In this comprehensive review of current literature, we examine the relationship between puberty, sex determinants and various traditional CVD-risk factors, as well as subclinical atherosclerosis in young people in general population. In addition, we evaluate the role of chronic inflammation, sex hormone therapy and health-risk behaviours on augmenting traditional CVD-risk factors and health outcomes, ultimately aiming to determine whether tailored management strategies for this age group are justified.

Association of reproductive factors and exogenous hormone use with distal sensory polyneuropathy among postmenopausal women in the United States: results from 1999 to 2004 NHANES

Postmenopausal status is a risk factor for distal sensory polyneuropathy-the most common type of peripheral neuropathy. We aimed to investigate associations between reproductive factors and history of exogenous hormone use with distal sensory polyneuropathy among postmenopausal women in the United States using data from the National Health and Nutrition Examination Survey 1999-2004, and to explore the modifying effects of ethnicity on these associations. We conducted a cross-sectional study among postmenopausal women aged ≥ 40 years. Women with a history of diabetes, stroke, cancer, cardiovascular disease, thyroid disease, liver disease, weak or failing kidneys, or amputation were excluded. Distal sensory polyneuropathy was measured using a 10-g monofilament test, and a questionnaire was used to collect data on reproductive history. Multivariable survey logistic regression was used to test the association between reproductive history variables and distal sensory polyneuropathy. In total, 1144 postmenopausal women aged ≥ 40 years were included. The adjusted odds ratios were 8.13 [95% confidence interval (CI) 1.24-53.28] and 3.18 (95% CI 1.32-7.68) for age at menarche < 11 years and time since menopause > 20 years, respectively, which were positively associated with distal sensory polyneuropathy; adjusted odds ratios were 0.45 for the history of breastfeeding (95% CI 0.21-0.99) and 0.41 for exogenous hormone use (95% CI 0.19-0.87) were negatively associated. Subgroup analysis revealed ethnicity-based heterogeneity in these associations. Age at menarche, time since menopause, breastfeeding, and exogenous hormone use were associated with distal sensory polyneuropathy. Ethnicity significantly modified these associations.

Early Life Environmental Exposure to Cadmium, Lead, and Arsenic and Age at Menarche: A Longitudinal Mother-Child Cohort Study in Bangladesh

BACKGROUND

Several metals act as endocrine disruptors, but there are few large longitudinal studies about associations with puberty onset.

OBJECTIVES

We evaluated whether early life cadmium, lead, and arsenic exposure was associated with timing of menarche.

METHODS

In a mother-child cohort in rural Bangladesh (n=935), the exposure was assessed by concentrations in maternal erythrocytes in early pregnancy and in girls' urine at 5 and 10 years of age using inductively coupled plasma mass spectrometry. The girls were interviewed twice, at average ages 13.3 [standard deviation (SD)=0.43] and 13.8 (SD=0.43) y, and the date of menarche, if present, was recorded. Associations were assessed using Kaplan-Meier analysis and multivariable-adjusted Cox regression.

RESULTS

In total, 77% of the girls (n=717) had reached menarche by the second follow-up. The median age of menarche among all girls was 13.0 y (25th-75th percentiles: 12.4-13.7 y). At 10 years of age, median urinary cadmium was 0.25μg/L (5th-95th percentiles: 0.087-0.72μg/L), lead 1.6μg/L (0.70-4.2μg/L), and arsenic 54μg/L (19-395μg/L). Given the same age, girls in the highest quartile of urinary cadmium at 5 and 10 years of age had a lower rate of menarche than girls in the lowest quartile, with an adjusted hazard ratio of (HR) 0.80 (95% CI: 0.62, 1.01) at 5 years of age, and 0.77 (95% CI: 0.60, 0.98) at 10 years of age. This implies that girls in the highest cadmium exposure quartile during childhood had a higher age at menarche. Comparing girls in the highest to the lowest quartile of urinary lead at 10 years of age, the former had a higher rate of menarche [adjusted HR = 1.23 (95% CI: 0.97, 1.56)], implying lower age at menarche, whereas there was no association with urinary lead at 5 years of age. Girls born to mothers in the highest quartile of erythrocyte arsenic during pregnancy were less likely to have attained menarche than girls born to mothers in the lowest quartile [adjusted HR= 0.79 (95% CI: 0.62, 0.99)]. No association was found with girls' urinary arsenic exposure.

DISCUSSION

Long-term childhood cadmium exposure was associated with later menarche, whereas the associations with child lead exposure were inconclusive. Maternal exposure to arsenic, but not cadmium or lead, was associated with later menarche. https://doi.org/10.1289/EHP11121.

Relationship between age at menarche and metabolic diseases in Korean postmenopausal women: The Korea National Health and Nutrition Examination Survey 2016-2018

BACKGROUND

Cardiovascular disease is the leading cause of morbidity and mortality in postmenopausal women. Early menarche may be associated with an increased risk of metabolic diseases such as diabetes and cardiovascular disease. This study aimed to investigate the effect of menarche age and the risk of diabetes and metabolic syndrome in Korean postmenopausal women.

METHODS

We analyzed 4,933 postmenopausal women (mean age: 64.7 years) using the Korean National Health and Nutritional Examination Survey 2016-2018. Subjects were divided into three groups according to menarche age (early menarche: ≤ 12 years (n = 451), reference: 13-16 years (n = 3,421), and late menarche: ≥ 17 years (n = 1,061)). Logistic regression analysis was used to estimate the odds ratio (OR) for diabetes and metabolic syndrome.

RESULTS

Women with an early menarche age were younger, more educated, and had higher income than the other groups (p-value < 0.001). There were no differences in body mass index, blood pressure, fasting glucose, HbA1c, and cholesterol levels among the three groups. After adjusting for potential confounding factors, early menarche age was significantly associated with the risk of diabetes (OR 1.435, 95% confidence interval (CI): 1.069-1.928). The prevalence of metabolic syndrome in all subjects was 41.1%. After adjusting for potential confounding factors, the OR of metabolic syndrome in the early menarche group was 1.213 (95% CI: 0.971-1.515).

CONCLUSION

The risk of diabetes was 1.43 times higher in postmenopausal Korean women with early menarche. Although the risk of metabolic syndrome was not statistically significant, it showed a tendency to increase in the early menarche group. Our results suggest that age at menarche may be helpful in diabetes risk stratification and early interventions for postmenopausal women.

Level of Psychological and Somatic Symptoms Predict Perimenopausal Syndrome Severity Better Than Obstetric and Psychiatric History Do Among Korean Women

OBJECTIVE

Menopause symptoms can vary in type, duration, and severity. The purpose of this study was to investigate the key factors predicting severe symptoms among Korean perimenopausal women with various demographic data, obstetric and psychiatric histories, and menopausal symptoms screening scale scores.

METHODS

Data were collected from 1,060 women, and 4 latent classes were identified using latent profile analysis, with 6 major categories of menopausal complaints. Among the 4 classes, we selectively used data from the "all unimpaired" and "all impaired" groups. Menopause rating scale (MRS), sociodemographic, obstetric, and psychiatric factors were assessed, and hierarchical logistic regression analyses were conducted with the "all impaired" group as a dependent variable.

RESULTS

Marital status and scores on the psychological and somatic subscales of the MRS were statistically related to being in the "all impaired" group. Otherwise, family history of menopausal symptoms, menarche age, and history of other psychiatric disorders were not statistically significant predictors of being in the "all impaired" group.

CONCLUSION

The psychological and somatic subscales of the MRS predict the severity of perimenopausal syndrome better than obstetric and psychiatric history do among Korean perimenopausal women. Psychological and somatic symptoms as well as genitourinary symptoms in menopausal patients should be closely evaluated.

Long-term health outcomes of early menarche in women: an umbrella review

BACKGROUND

There is limited comprehensive evidence on the potential association between early menarche and subsequent health outcomes.

AIM

To evaluate the existing evidence for the association of early menarche with later health outcomes and assesse the strength and validity of the evidence for these associations.

DESIGN

Umbrella review.

METHODS

We searched PubMed, Web of Science, Embase, CINAHL, Cochrane Database of Systematic Reviews and Google Scholar, and manually screened retrieved references to find systematic reviews and meta-analyses from inception to July 2021. Early menarche was defined by taking into account ethnicity and birth year, and the outcomes were long-term consequences in adulthood.

RESULTS

Thirteen reviews encompassing 283 original articles and over 6.8 million participants from 39 countries across 5 continents were included. In categorical outcomes, early menarche was associated with metabolic syndrome (n = 37 543 pooled adjusted relative risk [aRR] 1.56, 95% confidence interval (CI) 1.33, 1.83; high certainty [Hi]), endometrial cancer (n = 874 188, aRR 1.40, 95% CI 1.17, 1.68; Hi), type 2 diabetes mellitus/impaired glucose tolerance (n = 1 185 444, aRR 1.30, 95% CI 1.19, 1.42; Hi), breast cancer (n = 103 574, aRR 1.19, 95% CI 1.06, 1.33; Hi), death from all causes (n = 152 747, aRR 1.11, 95% CI 1.03, 1.19; Hi), obesity (n = 54 006, aRR 1.68, 95% CI 1.53, 1.84; moderate certainty [Mod]), gestational diabetes mellitus (n = 48 535, aRR 1.32, 95% CI 1.09, 1.58; Mod), hypertension (n = 1 682 689, aRR 1.24, 95% CI 1.20, 1.29; Mod), endometriosis (n = 885 390, aRR 1.22, 95% CI 1.09, 1.37; Mod), ovarian cancer (n = 1 022 451, aRR 1.17, 95% CI 1.04, 1.31; Mod) and asthma (n = 22 859, aRR 1.31, 95% CI 1.09, 1.57; low certainty [Lo]). For continuous outcomes, early menarche was associated with increased body mass index (BMI) in adults ≥40 years of age (n = 121 943, adjusted pooled standardized mean difference [aSMD] 0.30, 95% CI 0.28, 0.32; Mod), BMI in adults <40 years of age (n = 124 728, aSMD 0.39, 95% CI 0.36, 0.43; Mod), serum fasting insulin level (n = 17 020, aSMD 0.52, 95% CI 0.48, 0.57; Mod) and homeostatic model assessment of insulin resistance (n = 7925, aSMD 0.27, 95% CI 0.19, 0.35; Mod).

CONCLUSION

We found varied levels of evidence for the association between early menarche and the development of subsequent health problems. Our results recommend that physicians should pay attention to these associations, as early menarche can be a potential indicator of metabolic disorders and female-specific cancer and cause death in women.

Cohort-based analysis of maternal age at menarche in relation to young adult offspring anthropometric and metabolic parameters

OBJECTIVES

Age of menarche is a determinant factor of cardiometabolic risk, adiposity and stature at adulthood. However, little is known about the transgenerational effects of age of menarche, especially beyond childhood of any offspring, and the studies remain limited to anthropometric outcomes in children at birth or before adolescence. In the present study, we aim to investigate the relationship of maternal age at menarche (MAM) with anthropometric and metabolic parameters in the young adult offspring (aged 15-35 years) in a Persian population.

DESIGN, PATIENTS AND MEASUREMENTS

In this cohort-based cross-sectional study, we recruited 1139 mother-young adult dyads enroled in Rafsanjan Cohort Study (RCS) at adult RCS (aged 35-70 years) and youth RCS (aged 15-35 years) as part of the comprehensive PERSIAN (Prospective Epidemiological Research Studies in IrAN). In this study, MAM was categorized to early (MAM < 12 years), normal (12 ≤ MAM ≤ 14) and late menarche (MAM > 14 years). For these analyses, bivariate and multiple logistic regression models were used to investigate the relationships between late or early MAM and offspring anthropometric and metabolic parameters.

RESULTS

Early MAM displayed a significant association with an increased odds ratio (OR) of tall stature adjusting for sex, age, socioeconomic status index, maternal age at birth and maternal height (as genetically determined factor). Sensitivity analysis by sex indicated this relationship to be specific to male offspring only (adjusted OR: 1.84 95% CI: 1.13-3.00, p value: .014). In addition, late MAM displayed a significant association with reduced OR of overweight/obesity and abdominal obesity in daughters only (obesity adjusted OR: 0.49, 95% CI: 0.27-0.88, p value: .018, abdominal obesity adjusted OR: 0.44, 95% CI: 0.23-0.82, p value: .010). dose-response analysis by categorization of MAM, further supported our results. On the contrary, our analyses do not support a significant relationship between MAM and youth metabolic indices, that is, metabolic syndrome, fasting blood sugar (FBS), high-density lipoprotein (HDL) and triglyceride (TG).

CONCLUSIONS

The results of the present study indicate an association of maternal age of menarche with anthropometric measures of offspring in young adulthood in a sex differential manner. The data does not support a significant relationship between the metabolic indices FBS, TG and HDL in offspring with MAM. Overall, this study provides evidence for the intergenerational effects of age at menarche in the development of anthropometric measures in offspring in young adulthood (15-35), which is the first study of this kind in this age range.

Parity and Metabolic Syndrome Risk: A Systematic Review and Meta-Analysis of 15 Observational Studies With 62,095 Women

Background

Epidemiological studies have provided inconsistent evidence of the association between parity and metabolic syndrome (MetS) risk. We conducted this first systematic review and meta-analysis to comprehensively and precisely quantify this topic.

Methods

Comprehensive searches of PubMed, Embase, and the Web of Science databases were conducted to identify observational studies of the association between parity and MetS risk up to 30 January 2022. Study inclusion, data extraction, and quality assessment were checked and reviewed by two investigators independently. Random-effects models were applied to estimate pooled odds ratios (ORs) and 95% CIs. This study has been registered with PROSPERO.

Results

Two high-quality cohorts and thirteen medium-quality cross-sectional studies involving 62,095 women were finally included. Compared with the nulliparous, the pooled OR of MetS for the ever parity was 1.31 (95% CI = 0.91–1.88, I² = 72.6%, n = 3). Compared with the lowest parity number, the pooled OR of MetS for the highest parity number was 1.38 (95% CI = 1.22–1.57, I² = 60.7%, n = 12). For the dose-response analysis, the pooled OR of MetS for each increment of one live birth was 1.12 (95% CI = 1.05–1.19, I² = 78.6%, n = 6). These findings were robust across subgroups and sensitivity analyses. No evidence of heterogeneity between subgroups was indicated by meta-regression analyses.

Conclusion

The findings suggested that parity was associated with an increased risk of MetS. A sufficient number of large prospective cohort studies are required to fully verify our findings.

Systematic Review Registration

[https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42022307703].

Mediator or moderator? The role of obesity in the association between age at menarche and blood pressure in middle-aged and elderly Chinese: a population-based cross-sectional study

OBJECTIVE

We investigated the moderation/mediation between the age of menarche and obesity parameters in predicting blood pressure (BP) in middle-aged and elderly Chinese.

DESIGN

Our study is a population-based cross-sectional study.

SETTING

Participants in this study came from the China Health and Retirement Longitudinal Study (CHARLS).

PARTICIPANTS

The analytical sample included 4513 participants aged 45-96 years.

MAIN OUTCOME MEASUREMENTS

Data were selected from the CHARLS, a cross-sectional study. Between-group differences were evaluated using χ², t-test and one-way analysis of variance. The trend of related variables by characteristics was also tested using contrast analysis, as appropriate. Then, correlations between characteristics, moderator, mediator, and independent and dependent variables were used by Spearman's correlation test and Pearson's correlation test. Finally, the mediation analysis was performed by model 4 in PROCESS V3.3 macro for SSPSS, and moderation analysis was used by model 1 for assessment. All covariates were adjusted in the moderation or mediation models.

RESULTS

In the correlation analysis, body mass index (BMI) and waist circle (WC) level were positively correlated with both systolic blood pressure (SBP) and diastolic blood pressure (DBP) in women (BMI and DBP: r=0.221, p<0.001; WC and DBP: r=0.183, p<0.001; BMI and SBP: r=0.129, p<0.001; WC and SBP: r=0.177, p<0.001). Age of menarche was negatively correlated with DBP (r=-0.060, p<0.001). However, the age of menarche was not significantly correlated with SBP (r=-0.014, p=0.335). In the moderator analysis, after controlling for the potential confounders, the interaction term of obesity parameters×age of menarche was not significant for predicting either DBP (BMI: B=0.0260, SE=0.0229, p=0.2556, 95% CI -0.0189 to 0.071; WC: B=0.0099, SE=0.0074, p=0.1833, 95% CI -0.0047 to 0.0244) or SBP (BMI: B=0.0091, SE=0.0504, p=0.8561, 95% CI -0.0897 to 0.108; WC: B=-0.0032, SE=0.0159, p=0.8427, 95% CI -0.0343 to 0.028). All correlations were significant correlation between age of menarche, obesity parameters and BP except the path of the menarche age→SBP (with the addition of the BMI indicator: β=-0.0004, B=-0.0046, p=0.9797, 95% CI -0.3619 to 0.3526; with the addition of the WC indicator: β=0.0004, B=0.0044, p=0.9804, 95% CI -0.3439 to 0.3526) in crude model. In general, after controlling for potential confounders, BMI (DBP: β=-0.0471, B= -0.2682, p=0.0021, 95% CI -0.4388 to -0.0976; SBP: β=-0.0515, B=-0.6314, p<0.001, 95% CI -0.9889 to -0.2739) and WC (DBP: β=-0.0474, B= -0.2689, p<0.001, 95% CI -0.4395 to -0.0984; SBP: β=-0.0524, B=-0.6320, p<0.001, 95% CI -0.9832 to -0.2807) partly mediated the relationship between age of menarche and BP.

CONCLUSIONS

The interaction term of obesity parameters×age of menarche was not significant for predicting either DBP or SBP in women. Moreover, obesity parameters partly mediated the relationship between the age of menarche and BP.

The role of multiparity and maternal age at first pregnancy in the association between early menarche and metabolic syndrome among middle-aged and older women

OBJECTIVE

To analyze whether maternal age at first pregnancy and parity are mediators of the association between early menarche and metabolic syndrome in a sample of middle-aged and older women.

METHODS

Cross-sectional study of 428 women (40 to 80 y), who had experienced a pregnancy in their lifetime, was performed between 2014 and 2016. Age at first pregnancy, parity, and early menarche were self-reported. Metabolic syndrome was assessed using the criteria described by the National Cholesterol Education Program's Adult Treatment Panel III. The association between metabolic syndrome and early menarche was assessed by logistic regression analysis. The mediating role of age at first pregnancy and multiparity in the relationship between early menarche and metabolic syndrome was assessed through mediation analysis, adjusted for covariates.

RESULTS

According to adjusted logistic regression models, early menarche was associated with higher odds of prevalent metabolic syndrome (OR: 2.26; 95% CI: 1.15-4.46). Mediation analysis showed a significant direct effect of early menarche on metabolic syndrome (β: 0.808; 95% CI: 0.107-1.508). Of the two mediators tested, age at first pregnancy was significant (β: 0.065; 95% CI: 0.004-0.221), ie, participants with and without early menarche differ, on average, by 0.879 SDs in the log odds of MetS (total effect), of which 0.065 SDs (8%), on average, would be attributable to the effect of early menarche on age at first pregnancy (indirect effect), which, in turn, affects MetS.

CONCLUSIONS

Age at first pregnancy may partially contribute to the association between early menarche and metabolic syndrome among middle-aged and older women who had experienced a pregnancy over their lifetime.

Longitudinal association of dietary sources of animal and plant protein throughout childhood with menarche

Background

Inconsistent findings have been reported for associations between protein intake and age at menarche. We aimed to investigate the association between intake of protein and protein-containing food groups during childhood with menarche among Iranian girls.

Methods

Girls aged 6–18 years who did not experience menarche in the third or fourth examination cycles of the Tehran Lipid and Glucose Study were selected and were followed to the fifth examination cycle. Daily intakes of protein from different animal/plant sources and ten protein-containing food groups were assessed using a food frequency questionnaire at baseline (the third or fourth examination cycles). Occurrence of menarche and its onset age were asked during each examination cycle. Cox proportional hazards regression was used to estimating hazard ratios (HRs) and 95% confidence interval (95%CI) for the occurrence of menarche per one standard deviation (SD) of dietary intakes. Logistic regression was also used to estimate the odds of reaching menarche ≤12 years.

Results

During the study, 147(61%) of girls reached menarche, the median age at menarche was 12 years. The adjusted HRs (95% CI) for the occurrence of menarche per one-SD of dietary intakes were 0.68 (0.48, 0.98; p = 0.040) for plant protein and 1.36 (1.01, 1.84; p = 0.042) for animal protein after adjusting for baseline age, BMI Z-score, energy intake, and mother’s early menarche and education. Substituting 10-g animal protein with plant protein was associated with a 16% (95%CI: 5–25%; p = 0.006) lower risk of menarche. Dietary intakes of poultry (adjusted HR: 1.35; 95% CIs: 1.00–1.82; p = 0.049) and low-fat dairy (adjusted HR: 1.20; 95%CIs: 0.99–1.46; p = 0.064) were marginally associated with the increased risk of menarche. However, the odds of early menarche was significant only for plant protein (adjusted odds ratio = 0.39; 95% CI: 0.16–0.96; p = 0.040).

Conclusions

Our findings indicate that the risk of menarche increases by higher intakes of animal protein and decreases by plant protein. Intakes of poultry and low-fat dairy associate with a higher risk of menarche. The odds of menarche occurrence ≤12 years reduces by higher intakes of plant protein.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02670-8.

Clinical Implications for Women of a Low-Carbohydrate or Ketogenic Diet With Intermittent Fasting

Obesity in the United States is pervasive and associated with morbidity, mortality, and increased health care costs. For women, obesity may affect stages of life including early menarche, fertility, pregnancy, and menopause as a result of hormonal imbalances and insulin resistance. The insulin-carbohydrate model of obesity has been proposed as an explanation for growing obesity rates and can be used to target weight loss strategies by increasing insulin sensitivity. Together, low-carbohydrate dietary patterns along with intermittent fasting may help individuals with insulin resistance not only lose weight but also increase their insulin sensitivity. The purpose of this article is to review the epidemiology and physiology of obesity and the indicators for health while outlining strategies for nurses and other clinicians to use when counseling women who are following a low-carbohydrate or ketogenic diet with intermittent fasting for weight management.

Longitudinal 15-year follow-up of women with former early puberty: abnormal metabolic profiles not associated with earlier age at onset of puberty, but associated with obesity

BACKGROUND

In 2011, we described 104 girls who were diagnosed as early puberty (EP) during 2003-2005. In 2019-2020, the former EP women had been followed up 14 years after attaining their final height.

OBJECTIVE

To determine the reproductive function and metabolic profiles of former EP women.

STUDY DESIGN

Fifty-seven former EP women were evaluated for reproductive function and examined for health status. Blood samples were obtained for metabolic profiles of glucose, lipids and insulin, and testosterone levels.

RESULTS

In 2020, the average age of the study women was 22.9 ± 1.7 years. The average height was 156.7 ± 5.6 cm. The average weight had increased from 52.5 ± 7.8 kg in 2011 to 58.5 ± 11.1 kg in 2020 and average body mass index (BMI) from 21.4 ± 2.9 to 23.8 ± 4.0 kg/m². Obesity (BMI>25 kg/m²) was found in 8.8% (five participants) in 2011 and had increased to 22.8% (13 participants) in 2020. Most participants (79%) had regular menstrual cycle. Of the 17 married women, 4 (23.5%) had 1-2 children. Dividing the participants into obese and nonobese groups, the average fasting plasma glucose, lipid profiles, and testosterone levels were similar in both groups. However, the average systolic blood pressure and the serum insulin levels and HOMA-IR assessments were significantly higher in the obese group than in the nonobese group.

CONCLUSION

The former EP women had normal menstruation and reproductive function. The former EP women with average BMI at the follow-up had normal metabolic profiles while those who later became obese had significantly higher systolic blood pressure, serum insulin, and HOMA-IR assessments.

Early age at menarche and metabolic cardiovascular risk factors: mediation by body composition in adulthood

Evidence suggests that early menarche increases cardiometabolic risk, and adiposity would be a possible mediator of this association. We assessed the association between age at menarche and metabolic cardiovascular risk factors and estimated the indirect effect of body composition in adulthood. In 1982, all hospital births in the city of Pelotas/Brazil, were identified and live births were examined and have been prospectively followed. At 30 years, information on age at menarche and metabolic cardiovascular risk factors was available for 1680 women. Mediation analysis was performed using G-computation to estimate the direct effect of age at menarche and the indirect effect of body composition. The prevalence of age at menarche < 12 years was 24.5% and was associated with higher mean diastolic blood pressure [β: 1.98; 95% CI: 0.56, 3.40], total cholesterol (β: 8.28; 95% CI: 2.67, 13.88), LDL-cholesterol (β: 6.53; 95% CI: 2.00, 11.07), triglycerides (β: 0.11; 95% CI: 0.03, 0.19). For diastolic blood pressure, total cholesterol, LDL-cholesterol, triglycerides, body composition assessed by fat mass index captured from 43.8 to 98.9% of the effect of early menarche, except to systolic blood pressure, HDL-cholesterol, C-reactive-protein. Suggesting that the effect of menarche age < 12 years on some metabolic cardiovascular risk factors is mediated partially by body composition in adulthood.

Association between age at menarche and age at menopause among women of an indigenous population of North Bengal, India

Menarche and menopause are two major components of a woman's reproductive life. Ages at menarche and menopause vary widely between and within populations and are influenced by various factors, both genetic and environmental. The present community-based cross-sectional investigation aimed to assess the association between ages at menarche and natural menopause among women belonging to the indigenous Rajbanshi population of North Bengal, India. The investigation was carried out from January 2015 to May 2015 among 510 Rajbanshi women aged between 45 and 55 years residing in the district of Darjeeling, West Bengal, India. A structured schedule was used to collect data on ages at menarche and natural menopause, marital status, parity, education, age of first and last pregnancies, duration of breastfeeding, nature of occupation, health status, smoking and monthly family income. Anthropometric measurements of height and weight were recorded and Body Mass Index (BMI) calculated. The statistical analyses, which included descriptive statistics and binary logistic regression (BLR), were done using SPSS. The women's mean age of menarche and median age of natural menopause were 12.52 years and 50 years, respectively. The BLR analysis indicated that education, age at first pregnancy had significant effects on the age at natural menopause among women who experienced menarche at <12 years of age (p<0.05). In the case of women who attained menarche at ≥12 years of age, marital status, age at last pregnancy, parity, education, duration of breastfeeding, smoking, occupation, monthly income and BMI had a greater influence on age at natural menopause. There appears to be an indirect association between age at menarche and age at natural menopause, along with different predictor variables, among the Rajbanshi women.

Skin disease related to metabolic syndrome in women

Sex hormones are involved in pathways of metabolic syndrome (MetS), an observation supported by animal studies. The relationships of sex hormones with components of MetS, such as insulin resistance and dyslipidemia, have been studied in pre- and postmenopausal women. High testosterone, low sex hormone-binding globulin, and low estrogen levels increase the risks of MetS and type 2 diabetes in women. Cutaneous diseases that are sex hormone mediated, such as polycystic ovary syndrome, acanthosis nigricans, acne vulgaris, and pattern alopecia, have been associated with insulin resistance and increased risk for MetS. Furthermore, inflammatory skin conditions, such as hidradenitis suppurativa and psoriasis, increase the risk for MetS. Patients with such skin conditions should be followed for metabolic complications, and early lifestyle interventions toward these populations may be warranted.