Early menarche is associated with an increased risk of type 2 diabetes in rural Chinese women and is partially mediated by BMI: the Henan Rural Cohort Study

Inflammatory markers and androstenedione modify the effect of serum testosterone on obesity among men: Findings from a Chinese population

BACKGROUND

Few studies are available on the relationship of androstenedione with inflammation and obesity and the effect of androstenedione and inflammation on the association between testosterone and obesity. This study intended to examine the mediation effect of inflammatory markers on the association of testosterone with obesity and the moderation effect of androstenedione on the association of testosterone with inflammation and obesity in Chinese rural men.

MATERIALS AND METHODS

This cross-sectional research enrolled 2536 male rural inhabitants from the Henan Rural Cohort study. The serum concentrations of testosterone and androstenedione were determined by liquid chromatography-tandem mass spectrometry. Linear and logistic regression were used to examine the relationships between testosterone, inflammatory markers, and obesity. Mediation and moderation analyses were carried out to evaluate the potential effects of inflammatory markers on the relationship between testosterone and obesity, as well as androstenedione on the relationships of testosterone with inflammation and obesity.

RESULTS

After adjusting for confounding factors, the results showed that testosterone and androstenedione were negatively related to obesity, and inflammatory markers were positively associated with obesity. Besides, testosterone and androstenedione were negatively associated with inflammatory markers. Mediation analysis showed that white blood cell, neutrophil, monocyte, and high-sensitivity C-reactive protein had mediating effects on the association between testosterone and obesity. The most vital mediator was high-sensitivity C-reactive protein, and its proportion of the effect was 11.02% (defined by waist circumference), 11.15% (defined by waist-to-hip ratio), 12.92% (defined by waist-to-height ratio), and full mediating effect (defined by body mass index). Moreover, androstenedione played negative moderation effects on the associations of testosterone with inflammation and obesity.

CONCLUSION

Inflammatory markers and androstenedione were first found to have modifying effects on the association of testosterone with obesity. Higher levels of testosterone and androstenedione could reduce the inflammation level and risk of obesity, indicating their potential roles in the prevention and treatment of chronic diseases.

Genetic prediction of age at menarche, age at natural menopause and type 2 diabetes: A Mendelian randomization study

BACKGROUND AND AIMS

The relationship between reproductive factors and type 2 diabetes (T2D) is controversial; therefore, we explored the causal relationship of age at menarche (AAM), age at natural menopause (ANM), with the risk of T2D and glycemic traits using two-sample Mendelian randomization.

METHODS AND RESULTS

We used publicly available data at the summary level of genome-wide association studies, where AAM (N = 329,345), ANM (N = 69,360), T2D (N = 464,389). The inverse variance weighting (IVW) method was employed as the primary method. To demonstrate the robustness of the results, we also conducted various sensitivity analysis methods including the MR-Egger regression, the weighted median (WM) and the MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test. After excluding IVs associated with confounders, we found a causal association between later AAM and reduced risk of T2D (OR 0.81 [95% CI 0.75, 0.87]; P = 2.20 × 10^-8), lower levels of FI (β -0.04 [95% CI -0.06, -0.01]; P = 2.19 × 10^-3), FPG (β -0.03 [95% CI -0.05, -0.007]; P = 9.67 × 10^-5) and HOMA-IR (β -0.04 [95% CI -0.06, -0.01]; P = 4,95 × 10^-3). As for ANM, we only found a causal effect with HOMA-IR (β -0.01 [95% CI -0.02, -0.005]; P = 1.77 × 10^-3), but not with T2D.

CONCLUSIONS

Our MR study showed a causal relationship between later AAM and lower risk of developing T2D, lower FI, FPG and HOMA-IR levels. This may provide new insights into the prevention of T2D in women.

Mediation Effect of Obesity on the Association of Age at Menarche With Blood Pressure Among Women in Southwest China

Background Previous studies have been inconsistent about the association between age at menarche and high blood pressure. Little is known about such association across a wide range of menarcheal ages in less developed ethnic minority regions in China. We aimed to explore the association between age at menarche and high blood pressure (BP; ≥140/90 mm Hg) and to examine the mediating effect of obesity and the moderating effect of menopausal status on this association. Methods and Results A total of 45 868 women from the baseline data of the CMEC (China Multi-Ethnic Cohort) were included in this study. Binary logistic regression was used to analyze the relationship between age at menarche and high BP, and the mediation model was used to evaluate the mediating effects of body mass index and waist circumference on the association of age at menarche with high BP. The mean age at enrollment and age at menarche of participants in our study were 49.3 (SD=10.7) and 14.7 (SD=2.1) years, respectively. Late menarche was associated with a lower risk of high BP (odds ratio, 0.831 [95% CI, 0.728-0.950]). The risk of high BP decreased by 3.1% with each year's delay in the onset of menarche (P for trend <0.001). Body mass index and waist circumference could partially mediate the association of age at menarche and high BP with the indirect effect of body mass index (odds ratio, 0.998 [95% CI, 0.997-0.998]) and waist circumference (odds ratio, 0.999 [95% CI, 0.998-0.999]). In addition, the mediation effects were modified by the status of menopause. Conclusions Women with late menarche have a lower risk of high BP, and obesity could be one of the important mediators. Obesity prevention is an efficient strategy to reduce the association between age at menarche and high BP, especially in premenopausal women.

Interaction between gut microbiota and sex hormones and their relation to sexual dimorphism in metabolic diseases

Metabolic diseases, such as obesity, metabolic syndrome (MetS) and type 2 diabetes (T2D), are now a widespread pandemic in the developed world. These pathologies show sex differences in their development and prevalence, and sex steroids, mainly estrogen and testosterone, are thought to play a prominent role in this sexual dimorphism. The influence of sex hormones on these pathologies is not only reflected in differences between men and women, but also between women themselves, depending on the hormonal changes associated with the menopause. The observed sex differences in gut microbiota composition have led to multiple studies highlighting the interaction between steroid hormones and the gut microbiota and its influence on metabolic diseases, ultimately pointing to a new therapy for these diseases based on the manipulation of the gut microbiota. This review aims to shed light on the role of sexual hormones in sex differences in the development and prevalence of metabolic diseases, focusing on obesity, MetS and T2D. We focus also the interaction between sex hormones and the gut microbiota, and in particular the role of microbiota in aspects such as gut barrier integrity, inflammatory status, and the gut-brain axis, given the relevance of these factors in the development of metabolic diseases.

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.

Ideal Cardiovascular Health Metrics Attenuated Association of Age at Menarche With Type 2 Diabetes in Rural China

Objective: It is not clear whether ideal cardiovascular health (ICH) metrics have an impact on the association between age at menarche and type 2 diabetes (T2DM) in rural postmenopausal Chinese women.

Methods: In all, 15,450 postmenopausal women were enrolled from the Henan Rural Cohort study. Logistic regression models and interaction plots were used to analyze associations between age at menarche, ICH metrics and T2DM and interactive effects.

Results: Age at menarche was inversely associated with risk of T2DM, with adjusted OR of 1.224, 1.116, 1.00 and 0.971, 0.850 for those with age at menarche ≤13, 14, 15–16 (reference), 17, and ≥18 years, respectively, and each year of delay in menarche age correlated with a 5.1% lower risk of T2DM. Negative interaction effects of age at menarche and number of ICH metrics on the risk of T2DM was observed.

Conclusion: Meeting more ICH metrics might attenuate the association between early menstrual age and increased risk of T2DM, implying that meeting a higher number of ICH metrics may be an effective way to prevent T2DM for women of early menarche age.

Is age of menarche directly related to vitamin D levels?

INTRODUCTION

Very few studies have examined the direct link between age of menarche and vitamin D level and controversial results have been reported. This study aimed to investigate the association between vitamin D and age of menarche in a group of adolescent girls in an area with plenty of sunshine.

METHODS

At baseline, data were collected on 722 middle schoolgirls that were randomly selected by probability proportional to size sampling method. Of this group, 598 were followed including 173 who had their menarche during the follow-up. Serum 25-hydroxyvitamin D (25OHD) was measured at baseline using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data on potential confounders were collected at baseline from the parents using self-administered questionnaire and from schoolgirls through face-to-face interview. Multiple linear regression and time-to-event analysis were used to investigate the association between 25OHD concentration and age of menarche.

RESULTS

The mean (SD) age of the study group was 12.51 (0.91) years while the main (SD) age of menarche was 11.82 (1.04) years. The prevalence of vitamin D deficiency (<50 nmol/L) among schoolgirls was 91.69%. We found no evidence for the association between 25OHD levels and age of menarche before (β, .00, 95% confidence interval (CI) [-0.01, 0.01]; p = .808) or after (β, .00, 95% CI [-0.01, 0.01]; p = .765) adjusting for potential confounders. We also found no evidence for association between 25OHD status and age of menarche before (p = .424) or after (p = .356) adjusting for potential confounders. Time-to-event analysis showed no association between 25OHD level or status and age of menarche (p = .850).

CONCLUSION

In Middle Eastern setting, where vitamin D deficiency is common despite plenty of sunshine, vitamin D is not a major determinant of the age at menarche. Regardless of the link between vitamin D and age of menarche, there are several other health benefits of having adequate vitamin D level during childhood and adolescence.

Systolic blood pressure as the mediator of the effect of early menarche on the risk of coronary artery disease: A Mendelian randomization study

Background

Menarche timing may not be directly associated with the risk of coronary artery disease (CAD). Therefore, we investigated the roles of metabolic factors in explaining the effect of age at menarche on CAD risk.

Methods

We identified women with age at menarche and CAD by using three analytical methods: Mendelian randomization (MR), logistic regression analysis, and Cox proportional hazard regression. The first two analyses were performed in the Taiwan Biobank (N = 71,923) study, and the last analysis was performed in the Chin-Shan Community Cardiovascular Cohort study (N = 1,598). We further investigated the role of metabolic factors in mediating the effect of age at menarche on CAD risk by using three complementary methods with mediation analyses.

Results

One standard deviation of earlier age at menarche was associated with a 2% higher CAD risk [odds ratio = 1.02, 95% confidence interval (CI) = 1.001-1.03] in the MR analysis, an 11% higher risk (odds ratio = 1.11, 95% CI = 1.02-1.21) in the logistic regression analysis, and a 57% higher risk (hazard ratio = 1.57, 95% CI = 1.12-2.19) in the Cox proportional hazard regression. All the analyses consistently supported the role of systolic blood pressure in mediating this effect. The MR results indicated that 29% (95% CI = 26%-32%) of the effect of genetically predicted earlier age at menarche on CAD risk was mediated by genetically predicted systolic blood pressure.

Conclusion

The results obtained using different analytical methods suggest that interventions aimed at lowering systolic blood pressure can reduce the cases of CAD attributable to earlier age at menarche.

Gonadal hormonal factors before menopause and incident type 2 diabetes in women: A 22-year follow-up of 83 799 women from the E3N cohort study

BACKGROUND

In many populations the incidence of type 2 diabetes is higher in men than in women. This may be explained by exposure to female gonadal hormones, but so far, there is no consensus on their role over the life course in type 2 diabetes etiology.

METHODS

Data are from 83 799 French women from the E3N (Etude Épidémiologique de Femmes de la Mutuelle Générale de l'Education Nationale) cohort study, followed for 22 years. Multivariable Cox models including classical risk factors were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) between gonadal hormonal factors and incident type 2 diabetes.

RESULTS

Older age at menarche, more menstrual cycles, older age at menopause, longer duration of exposure to gonadal hormones and breastfeeding were inversely associated with incident type 2 diabetes cases (n = 4806). While a longer duration of menstrual cycles (HR = 1.23 [95% CI: 1.07-1.41] comparing ≥32 vs ≤24 days) and use of contraceptive pills (HR = 1.33 [1.25-1.42]) were associated with a greater risk of type 2 diabetes.

CONCLUSIONS

In women, a longer exposure to endogenous gonadal hormones with a later menopause as well as breastfeeding were associated with a lower risk of developing type 2 diabetes, independently of classical diabetes risk factors. In contrast, the use of contraceptive agents was associated with incident diabetes, but the influence of each type of contraception and of exposure duration remain to be investigated.

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.

Growth and socio-economic status, influence on the age at menarche in school going girls

INTRODUCTION

Onset age at menarche has been considered an important indicator of reproductive maturity in females and reflects the health status of the population. The purpose of this study was to determine the mean menarcheal age and to examine whether anthropometric and socio-economic status (SES) influences age at menarche in the girls from Punjab province of Pakistan.

METHODS

In this population-based cross-sectional study, 10,050 school-going girls aged 8-16 years from 35 schools across 12 districts of Punjab were recruited. Menarcheal data was obtained by using a questionnaire, while the anthropometric data were obtained by the measurements of standing height, body weight, waist, and hip circumference. The anthropometric indices of pre- and post-menarcheal girls were compared. Student's t-test, ANOVA, and post-hoc Tukey's test was applied for comparison between two and multiple groups respectively, P < 0.05 was considered statistically significant.

RESULTS

There was a normal distribution of age at menarche and mean was 12.4 years in the study population. The girls who reached menarche were found to be taller and heavier with higher BMIs, having a greater waist and hip circumference as compared to their pre-menarcheal peers. Waist-hip-ratio was less, and the waist-to-height ratio was higher in post-menarcheal as compared to pre-menarcheal girls. The girls belonging to low SES had delayed onset of menarche as compared to those belonging to middle/high SES.

CONCLUSION

The age at menarche was associated with SES and changes in various anthropometric measurements reflecting the growth status of girls.

Mediation effect of body mass index on the association between spicy food intake and hyperuricemia in rural Chinese adults: the Henan rural cohort study

Background

The relationship of spicy food intake with hyperuricemia remains unknown. The objective of this study was to examine the association between spicy food intake and hyperuricemia, and whether this association was mediated by body mass index (BMI) in Chinese rural population.

Methods

38, 027 adults aged 18–79 years were recruited from the Henan Rural Cohort Study. Information on spicy food intake was obtained using a validated questionnaire survey. Multivariable logistic regression model was used to estimate the association between spicy food intake and hyperuricemia, multiple linear regression model was performed to estimate the relationships between spicy food intake, BMI and serum urate level. BMI was used as a mediator to evaluate the mediation effect.

Results

After adjusting for potential confounders, compared with no spicy food flavor, the odds ratio (OR) and 95% confidence interval (CI) of mild, middle, and heavy flavor for hyperuricemia were 1.09 (1.00–1.19), 1.10 (0.97–1.24), and 1.21 (1.10–1.46), respectively (P_trend = 0.017). Similarly, compared with those without intake in spicy food, the multivariable adjusted OR (95% CI) of 1-2 days/week, 3–5 days/week, and 6–7 days/week were 1.15 (1.01–1.31), 1.14 (1.01–1.30) and 1.15 (1.05–1.26), respectively (P_trend = 0.007). However, when we further controlling for BMI, the associations were substantially attenuated. Furthermore, mediation analysis showed that BMI play a full mediating role in the relationship of spicy food intake with hyperuricemia.

Conclusion

Spicy food flavor and intake frequency are positively related with hyperuricemia in Chinese rural population. BMI may play a full mediating role in the relationship.

Trial registration

The Henan Rural Cohort Study registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 2015-07-06.

Effect of the Age at Menarche and Menopause Status Interaction on Type 2 Diabetes: The Henan Rural Cohort Study

PURPOSE

The aims of this study were to evaluate the effect of age at menarche (AM) on type 2 diabetes mellitus (T2DM) and to assess whether the fasting plasma glucose (FPG) and homeostasis model assessment (HOMA) index responses to AM and menopause status interact in Chinese rural adults.

METHODS

A cross-sectional, population-based study including 23 138 participants was performed. Logistic regression and multivariable linear regression were performed to investigate the relationship between AM and glucose status. Generalized linear model was used to calculate the interaction term of AM and menopause status on FPG and the HOMA index. Interaction plot was used to interpret the significant interaction effect.

RESULTS

Women in the later menarche age group (≥18 years) had a 17.7% lower risk of T2DM (95% confidence interval [CI]: 0.712-0.951, P = .008), after adjusting for multiple variables. Further adjustment for body mass index (BMI) completely attenuated this association (odds ratio = 0.884, 95% CI: 0.764-1.024, P = .099). A significant interaction effect of AM and menopause status on T2DM (P = .004) was observed. The adverse effects of menopausal status on FPG and HOMA-2 of insulin resistance decreased with increasing menarche age, and the age ranges were limited to <18 and 9 to 19 years, respectively.

CONCLUSIONS

Later menarche was associated with a lower risk of T2DM, and the association appears to be mediated by BMI. More importantly, the adverse effect of menopause status on T2DM was decreased along with increasing menarche age.