Female reproductive history and risk of type 2 diabetes: A prospective analysis of 126 721 women

Longitudinal assessment of classic and 11-oxygenated androgen concentrations and their association with type 2 diabetes mellitus development: the Tromsø study

AIM

We aimed to investigate changes in pre-diagnostic concentrations of classic and 11-oxygenated androgens in type 2 diabetes (T2DM) cases and healthy controls, associations between androgen concentrations and T2DM, and the potential for androgens to improve the prediction of T2DM when considered in combination with established risk factors.

METHODS

Androgen concentrations were analysed in serum samples from 116 T2DM cases and 138 controls at 3, pre-diagnostic time-points: 1986/87 (T1), 1994/95 (T2), and 2001 (T3). Generalised estimating equations were used to longitudinally examine androgen concentrations, and logistic regression models were used to estimate the odds ratios (OR) of T2DM at each time-point. Logistic regression models were also used to calculate area under the receiver operating characteristics curve (AROC) from models including established risk factors alone (ERF model) and established risk factors plus each androgen, respectively, which were compared to identify improvements in predictive ability.

RESULTS

For women, no significant associations were observed between any of the investigated androgens and T2DM after adjusting for confounders. For men, after adjusting for confounders, concentrations of all investigated 11-oxygenated androgens were higher in cases than controls at one or several time-points. We observed associations between T2DM and concentrations of 11-ketoandrostenedione (OR: 1.59) and 11-ketotestosterone (OR: 1.62) at T1; and 11-hydroxyandrostenedione (OR: 2.00), 11-hydroxytestosterone (OR: 1.76), 11-ketoandrostenedione (OR: 1.84), 11-ketotestosterone (OR: 1.78) and testosterone (OR: 0.45) at T3 in men. The addition of these androgens (including 11-hydroxytestosterone at T2) to the ERF model resulted in an improved ability to predict T2DM in men (AROC: 0.79-0.82). We did not observe significant differences in changes in androgen concentrations over time between cases and controls in either sex.

CONCLUSION

Our results demonstrate that testosterone and 11-oxygenated androgens are associated with T2DM in men before diagnosis and may be potential biomarkers in T2DM risk assessment.

The global burden of disease due to benign gynecological conditions: A call to action

OBJECTIVE

Focusing on low- and middle-income countries (LMICs), this article uses data from the Global Burden of Disease (GBD) database to highlight the burden of morbidity due to benign gynecological conditions (BGCs).

METHODS

We analyzed 2019 morbidity data for all BGCs, measured as years lost to disability (YLDs). Disease burden was calculated for individual conditions, BGCs overall, and percentages of overall disease burden from all conditions. The same data extraction was performed for malaria, tuberculosis, and HIV/AIDS for comparison. The data were subcategorized by age and World Bank income level.

RESULTS

BGCs are major causes of disease morbidity worldwide. For women aged 15 years and over in high-income countries (HICs), 3 588 157 YLDs (3.94% of all YLDs) were due to BGC. In LMICs, 18 242 989 YLDs (5.35% of all YLDs) were due to BGCs. The highest burden of BGCs is seen during the reproductive years where conditions driven or exacerbated by reproductive hormones are the major causes of morbidity. In LMICs, for women aged 15-49, 14 574 100 YLDs (7.75% of all YLDs) were due to BGCs, declining to 3 152 313 YLDs (3.04%) in women aged 50-69 and 529 399 YLDs (1.06%) in women age 70+.

CONCLUSION

These data demonstrate a huge burden of morbidity due to BGCs. There is an urgent need for international stakeholders to prioritize the treatment and prevention of BGCs.

Menarche age and the risk of diabetes: A cross-sectional study in South-Eastern Iran

Background and Aims

Diabetes is a major public health problem worldwide. This study aimed to determine the relationship between menarche age and overt diabetes in southeast Iran.

Methods

This cross-sectional study was conducted on 6094 eligible women between the ages of 35 and 70 participating in the Zahedan Adult Cohort Study. Demographic and background data, fertility, anthropometry, and disease history were collected based on a questionnaire. Menarche age was classified into five categories (under 12 years, 12, 13, 14, 15 years and more). Diabetes is defined as a blood sugar of 126 or more according to the definition by the American Diabetes Association. Data analysis was done using SPSS 26 software. Descriptive analysis was performed with frequency, percentage, mean, and standard deviation; and analytical analysis using chi-square and logistic regression tests. The significance level in this study was p < 0.05.

Results

The participants' mean age was 49.41 ± 8.88, and the mean age at menarche was 13 ± 1.49. 22.8% (1389 women) of participants with diabetes and 77.2% (4705 women) did not have diabetes. The findings showed that the chance of developing diabetes in women with a menarche age <12 years was significantly higher than in women with a menarche age of 13 years (reference) (OR = 1.23, 95% CI: 0.96, 1.51). This relationship was significant after adjusting variables such as body mass index, education level, fertility factors, history of diabetes, and reproductive diabetes (OR = 1.21, 95% CI: 0.90, 1.44, p = 0.04).

Conclusion

Our findings suggest that young age at menarche may be a risk factor for diabetes in adulthood. Further prospective studies are needed to confirm our findings. However, it is suggested to pay attention to it in diabetes screening so that, if possible, by identifying people at risk and implementing prevention programs, the adverse consequences of diabetes can be reduced.

Association between female-specific reproductive factors and leukocyte telomere length

STUDY QUESTION

What are the associations between female-specific reproductive factors and leukocyte telomere length (LTL)?

SUMMARY ANSWER

Early menarche, early menopause, short reproductive lifespan, early age at first birth, multiparity, and use of oral contraceptives (OCs) and hormone replacement therapy (HRT) were associated with shorter LTL.

WHAT IS KNOWN ALREADY

Reproductive factors have been associated with age-related diseases, but their associations with cellular aging, as indicated by LTL, are unclear.

STUDY DESIGN, SIZE, DURATION

This population-based study included 224 965 women aged 40-69 years from the UK Biobank between 2006 and 2010.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women aged 40-69 were included. Female-specific reproductive factors, including age at menarche, age at natural menopause, reproductive lifespan, number of live births, age at first live birth, history of stillbirth, history of miscarriage, and use of OCs and HRT were self-reported. LTL was measured using a validated polymerase chain reaction method. Multiple linear regression and restricted cubic spline models were applied to explore the association between each reproductive factor and LTL.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjustment for potential confounders, early menarche (<12 years; percent change, per unit change in LTL Z score: -1.29%, 95% CI: -2.32%, -0.26%), early menopause (<45 years; percent change: -7.18%, 95% CI: -8.87%, -5.45%), short reproductive lifespan (<30 years; percent change: -6.10%, 95% CI: -8.14%, -4.01%), multiparity (percent change: -3.38%, 95% CI: -4.38%, -2.37%), early age at first live birth (<20 years; percent change: -4.46%, 95% CI: -6.00%, -2.90%), and use of OCs (percent change: -1.10%, 95% CI: -2.18%, -0.02%) and HRT (percent change: -3.72%, 95% CI: -4.63%, -2.80%) were all significantly associated with shorter LTL. However, no significant association was found for history of miscarriage and stillbirth. We observed nonlinear relationships of age at menarche, age at natural menopause, reproductive lifespan, and age at first live birth with LTL (Pnonlinear < 0.05).

LIMITATIONS, REASONS FOR CAUTION

Considering that the participants were predominantly of European ethnicity, the findings may not be generalizable to women of other ethnic backgrounds.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings suggest that early menarche, early menopause, short reproductive lifespan, early age at first birth, multiparity, and use of OCs and HRT were associated with shorter LTL, which has been linked to various chronic diseases. The accelerated shortening of telomeres may potentially contribute to the development of chronic diseases related to reproductive factors.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the National Natural Science Foundation of China (82003479, 82073660), Hubei Provincial Natural Science Foundation of China (2023AFB663), and the China Postdoctoral Science Foundation (2019M662646, 2020T130220). The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Ethnic Differences in the Association Between Age at Natural Menopause and Risk of Type 2 Diabetes Among Postmenopausal Women: A Pooled Analysis of Individual Data From 13 Cohort Studies

OBJECTIVE

To investigate associations between age at natural menopause, particularly premature ovarian insufficiency (POI) (natural menopause before age 40 years), and incident type 2 diabetes (T2D) and identify any variations by ethnicity.

RESEARCH DESIGN AND METHODS

We pooled individual-level data of 338,059 women from 13 cohort studies without T2D before menopause from six ethnic groups: White (n = 177,674), Chinese (n = 146,008), Japanese (n = 9,061), South/Southeast Asian (n = 2,228), Black (n = 1,838), and mixed/other (n = 1,250). Hazard ratios (HRs) of T2D associated with age at menopause were estimated in the overall sample and by ethnicity, with study as a random effect. For each ethnic group, we further stratified the association by birth year, education level, and BMI.

RESULTS

Over 9 years of follow-up, 20,064 (5.9%) women developed T2D. Overall, POI (vs. menopause at age 50-51 years) was associated with an increased risk of T2D (HR 1.31; 95% CI 1.20-1.44), and there was an interaction between age at menopause and ethnicity (P < 0.0001). T2D risk associated with POI was higher in White (1.53; 1.36-1.73), Japanese (4.04; 1.97-8.27), and Chinese women born in 1950 or later (2.79; 2.11-3.70); although less precise, the risk estimates were consistent in women of South/Southeast Asian (1.46; 0.89-2.40), Black (1.72; 0.95-3.12), and mixed/other (2.16; 0.83-5.57) ethnic groups. A similar pattern, but with a smaller increased risk of T2D, was observed with early menopause overall (1.16; 1.10-1.23) and for White, Japanese, and Chinese women born in 1950 or later.

CONCLUSIONS

POI and early menopause are risk factors for T2D in postmenopausal women, with considerable variation across ethnic groups, and may need to be considered in risk assessments of T2D among women.

Parity and incident type 2 diabetes in older Chinese women: Guangzhou Biobank Cohort Study

This study examined the association between parity and incident type 2 diabetes in older Chinese women and estimated the mediation effect of adiposity indicators. A total of 11,473 women without diabetes at baseline from 2003 to 2008 were followed up until 2012. We used Cox proportional hazards regression to assess the association between parity and incident type 2 diabetes, and mediation analysis to estimate the mediation effect of adiposity indicators. Compared to women with one parity, the hazard ratio (HR) (95% confidence interval (CI)) for incident type 2 diabetes was 0.85 (0.44-1.63), 1.20 (1.11-1.30), 1.28 (1.16-1.41) and 1.27 (1.14-1.42) for women with parity of 0, 2, 3, and ≥ 4, respectively. The proportion of indirect effect (95% CI) mediated by body mass index, waist circumference, hip circumference, waist-to-hip ratio, waist-to-height ratio and body fat percentage was 26.5% (19.2-52.2%), 54.5% (39.4-108.7%), 25.1% (18.2-49.1%), 35.9% (25.6-74.1%), 50.3% (36.5-98.6%) and 15.1% (- 66.4 to 112.3%), respectively. Compared to women with one parity, women with multiparity (≥ 2) had a higher risk of incident type 2 diabetes and up to half of the association was mediated by abdominal obesity.

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.

Hysterectomy and women's health in India: evidence from a nationally representative, cross-sectional survey of older women

BACKGROUND

Hysterectomy, particularly when conducted in women younger than 45 years, has been associated with increased risk of non-communicable diseases. In India, research indicates that hysterectomy is a common procedure for women, but there have been no studies on its long-term effects. We examined patterns of hysterectomy amongst women in India and associations with their health and well-being in later life.

METHODS

This analysis utilised the first wave of the Longitudinal Study on Aging in India, a nationally representative study of adults that included a module on health and well-being. We analysed data on 35,083 women ≥45 years in India. We estimated prevalence of hysterectomy and performed multivariable logistic regression to identify associated risk factors and to examine the association between hysterectomy status and eight self-reported chronic conditions, hospitalisation and mobility.

RESULTS

The prevalence of hysterectomy among women >=45 years was 11.4 (95% CI: 10.3, 12.6), with higher odds among urban women (aOR: 1.39; 1.17,1.64) and higher economic status (highest compared to lowest quintile: aOR: 1.95; 1.44, 2.63). Hysterectomy history was associated with four chronic conditions: hypertension (aOR: 1.51; 95% CI: 1.28, 1.79), high cholesterol (aOR: 1.43; 1.04, 1.97), diabetes (aOR: 1.69; 1.28, 2.24), and bone/joint disease (aOR: 1.54; 1.20, 1.97) and higher odds of any hospitalisation in the past year (aOR: 1.69; 1.36, 2.09).

CONCLUSIONS

In India, evidence suggests that hysterectomy is associated with major chronic conditions. The assessment for hysterectomy as a treatment option for gynaecological morbidity should consider potential health consequences in later life.

Association of age at menopause with type 2 diabetes mellitus in postmenopausal women in the United States: National Health and Nutrition Examination Survey 2011-2018

Introduction

The present study aimed to examine the impact of age at menopause on the type 2 diabetes mellitus (T2DM) risk in postmenopausal women.

Material and methods

We included 4,968 postmenopausal women from the National Health and Nutrition Examination Survey 2011-2018. Age at menopause was measured by single year and categorically (< 40 years, 40-44 years, 45-54 years, 55 years and above). The outcome variable T2DM was measured with self-report and fasting blood glucose level. We performed logistic regression to estimate the odds ratio (OR) (95% confidence interval [CI]). Linear regression was used to examine the correlation between age at menopause and age at T2DM.

Results

Of the 4,968 postmenopausal women, 796 (16.0%) had T2DM after menopause. The mean age at menopause was 44.2 years. The mean age at T2DM was 57.2 years. Adjusting for potential confounders, the ORs for the association between age at menopause of < 40 years, 40-44 years and ≥ 55 years and T2DM were 1.97 (95% CI: 1.47-2.63), 1.27 (95% CI: 0.90-1.79) and 0.98 (95% CI: 0.66-1.45), respectively, compared to women having menopause at age 45 to 54 years. Each increase by 1 year in age at menopause was associated with a 3% reduction in the prevalence of T2DM (95% CI: 2-5). Age at menopause was significantly correlated with age at T2DM. Each 1-year increase in age at menopause might lead to a decrease of 0.39 years in age at T2DM.

Conclusions

Premature menopause was associated with increased T2DM risk in women. The earlier menopause occurs, the younger is the age at which T2DM may occur.

Sex difference in circulating PCSK9 and its clinical implications

Proprotein convertase subtilisin kexin type 9 (PCSK9) is a proprotein convertase that increases plasma low-density lipoprotein cholesterol (LDL-C) levels by triggering the degradation of LDL receptors (LDLRs). Beyond the regulation of circulating LDL-C, PCSK9 also has direct atherosclerotic effects on the vascular wall and is associated with coronary plaque inflammation. Interestingly, emerging data show that women have higher circulating PCSK9 concentrations than men, suggesting that the potential roles of PCSK9 may have different impacts according to sex. In this review, we summarize the studies concerning sex difference in circulating levels of PCSK9. In addition, we report on the sex differences in the relations of elevated circulating PCSK9 levels to the severity and prognosis of coronary artery disease, the incidence of type 2 diabetes mellitus, and neurological damage after cardiac arrest and liver injury, as well as inflammatory biomarkers and high-density lipoprotein cholesterol (HDL-C). Moreover, sex difference in the clinical efficacy of PCSK9 inhibitors application are reviewed. Finally, the underlying mechanisms of sex difference in circulating PCSK9 concentrations and the clinical implications are also discussed.

Contribution of environmental factors and female reproductive history to hypertension and obesity incidence in later life

BACKGROUND

Hypertension (HT) and obesity, which are important risk factors for cardiovascular diseases, are complex traits determined by multiple biological and behavioural factors. However, the role of female reproductive history in evaluating HT and obesity is still unclear.

AIM

To investigate the long-term effects of reproductive factors on the probability of obesity and HT in later life after adjusting for socio-demographic and lifestyle behaviour factors.

SUBJECTS AND METHODS

A total of 503 women (39 - 65 years) were recruited from different localities in Slovakia. Multivariable logistic regression analyses were performed to test the associations.

RESULTS

Early menarche age of 11 years and under was associated with twice higher probability of obesity at midlife, independent of environmental confounders (OR = 2.27, CI = 1.35 - 3.81, p = 0.002). Breastfeeding (Bf) women had a lower likelihood of obesity in later life than non-Bf parous women, independent of environmental confounders (OR = 0.35, CI = 0.17 - 0.72, p = 0.004). Finally, age at menarche was associated with obesity-associated HT.

CONCLUSION

Reproductive factors are significantly associated with obesity and obesity-associated HT in later life. The age at menarche and Bf can be risk factors for early identification of women with increased likelihood of adult cardiovascular risk.

Hyperinsulinemia induces early and dyssynchronous puberty in lean female mice

Girls with obesity are at increased risk of early puberty. Obesity is associated with insulin resistance and hyperinsulinemia. We hypothesized that insulin plays a physiological role in pubertal transition, and super-imposed hyperinsulinemia due to childhood obesity promotes early initiation of puberty in girls. To isolate the effect of hyperinsulinemia from adiposity, we compared pre-pubertal and pubertal states in hyperinsulinemic, lean muscle (M)-insulin-like growth factor 1 receptor (IGF-1R)-lysine (K)-arginine (R) (MKR) mice to normoinsulinemic WT, with puberty onset defined by vaginal opening (VO). Our results show MKR had greater insulin resistance and higher insulin levels (P < 0.05) than WT despite lower body weight (P < 0.0001) and similar IGF-1 levels (P = NS). Serum luteinizing hormone (LH) levels were higher in hyperinsulinemic MKR (P = 0.005), and insulin stimulation induced an increase in LH levels in WT. VO was earlier in hyperinsulinemic MKR vs WT (P < 0.0001). When compared on the day of VO, kisspeptin expression was higher in hyperinsulinemic MKR vs WT (P < 0.05), and gonadotropin-releasing hormone and insulin receptor isoform expression was similar (P = NS). Despite accelerated VO, MKR had delayed, disordered ovarian follicle and mammary gland development. In conclusion, we found that hyperinsulinemia alone without adiposity triggers earlier puberty. In our study, hyperinsulinemia also promoted dyssynchrony between pubertal initiation and progression, urging future studies in girls with obesity to assess alterations in transition to adulthood.

Sibling group size and BMI over the life course: Evidence from four British cohort studies

Only children, here defined as individuals growing up without siblings, are a small but growing demographic subgroup. Existing research has consistently shown that, on average, only children have higher body mass index (BMI) than individuals who grow up with siblings. How this difference develops with age is unclear and existing evidence is inconclusive regarding the underlying mechanisms. We investigate BMI trajectories for only children and those with siblings up to late adolescence for four British birth cohorts and across adulthood for three cohorts. We use data on BMI from ages 2-63 years (cohort born 1946); 7-55 years (born 1958); 10-46 (born 1970) and 3-17 years (born 2000-2002). Using mixed effects regression separately for each cohort, we estimate the change in BMI by age comparing only children and those with siblings. The results show higher average BMI among only children in each cohort, yet the difference is substantively small and limited to school age and adolescence. The association between sibling status and BMI at age 10/11 is not explained by differential health behaviours (physical activity, inactivity and diet) or individual or family background characteristics in any of the cohorts. Although persistent across cohorts, and despite the underlying mechanism remaining unexplained, the substantively small magnitude of the observed difference and the convergence of the trajectories by early adulthood in all cohorts raises doubts about whether the difference in BMI between only children and siblings in the UK context should be of research or clinical concern. Future research could usefully be directed more at whether only children experience elevated rates of disease, for which high BMI is a risk factor, at different stages of the life course and across contexts.

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.

Epidemiological studies of the association between reproductive lifespan characteristics and risk of Type 2 diabetes and hypertension: A systematic review

Some reproductive factors are found to be associated with metabolic outcomes in women; however, little is known about reproductive lifespan characteristics and the mutual effect of age at menarche and age at menopause on cardiovascular risk. This systematic review evaluated reproductive lifespan characteristics and describes the mutual effect of age at menarche and age at menopause on the risk of type 2 diabetes (T2DM) and hypertension at midlife. PubMed, EMBASE, and Web of Science were screened for studies published up to September 1, 2020. The individual effect estimates were reviewed and synthesized without meta-analysis due to methodological and clinical or conceptual diversity in reported studies. Of the 3033 identified studies, 20 were included in the final synthesis: 6 reported reproductive life span; 12 reported age at menarche, and 7 reported age at menopause. Synthesis of two cohorts, with a median follow-up of 9-11 years, showed that a shorter reproductive lifespan was positively associated with T2DM, yielding 6-15% higher risk of T2DM for a one-year decrease in reproductive lifespan. A few studies also demonstrated that women who experienced early menarche (four of six studies) and early menopause (two of five studies) were positively associated with risk of T2DM. The association between reproductive lifespan and hypertension was unclear due to the limited availability of studies. Our findings suggest that a shorter reproductive lifespan is associated with T2DM risk in postmenopausal women, especially those with early menarche and early menopause. Large cohort studies are needed to assess the association between reproductive lifespan and incident hypertension in midlife.

Associations between parity, pregnancy loss, and breastfeeding duration and risk of maternal type 2 diabetes: An observational cohort study

BACKGROUND

Parity, pregnancy loss, and breastfeeding duration were found to be associated with diabetes. However, the results are inconsistent. Also, no epidemiological studies have examined the association of these reproductive factors with diabetes in the same large population. We aim to investigate the associations between parity, pregnancy loss, breastfeeding duration, and the risk of maternal diabetes in middle-aged and elderly Chinese females.

METHODS

We included 131 174 females aged ≥40 years from the REACTION study (Risk Evaluation of Cancers in Chinese Diabetic Individuals: A Longitudinal Study). Multivariable linear regression and logistic regression were used to assess the association between parity, pregnancy loss, and breastfeeding duration and type 2 diabetes.

RESULTS

The number of parities and breastfeeding duration were positively related to fasting plasma glucose, 2-hour postload glucose, glycosylated hemoglobin, and homeostatic model assessment of insulin resistance. Compared with those with one birth, nulliparous women or women with 2 or ≥3 births had a significantly increased risk of diabetes. The odds ratios (OR) and 95% confidence intervals (CI) were 1.27 (1.10-1.48), 1.17 (1.12-1.22), and 1.28 (1.21-1.35), respectively. Compared with women without pregnancy loss, those who underwent 2 (OR 1.09; 95% CI, 1.04-1.14) or ≥3 pregnancy losses (OR 1.11; 95% CI, 1.04-1.18) had an increased risk of diabetes. Moreover, women with a breastfeeding duration ≥0 to 6 months (OR 0.82; 95% CI, 0.75-0.90) and ≥6 to 12 months (OR 0.94; 95% CI, 0.89-0.99) had a significantly lower risk of diabetes.

CONCLUSIONS

Nulliparous women or women with multiparity or more than one pregnancy loss have an increased risk of diabetes in later life, while women who breastfeed more than 0 to 12 months have a lower risk of diabetes.

The association of parity/live birth number with incident type 2 diabetes among women: over 15 years of follow-up in The Tehran Lipid and Glucose Study

Background

Childbearing may increase the future risk of developing type 2 diabetes mellitus (T2DM) in mothers. However, the issue is not clear completely and not investigated in the Middle East, a region with a high burden of T2DM. In the current study, we examined the association of parity/live birth number with incident T2DM among Iranian women.

Methods

The study population included 2552 women aged 30–65 years recruited in 1999–2001 and were followed for incident T2DM by 3-year intervals. Multivariable Cox proportional hazard models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of the parity/live birth number for incident T2DM. Parity number was defined as the number of live childbirth (number of live birth) plus the number of stillbirth (defined as birth of an infant that died after the 20th week of pregnancy in the uterus).

Results

During a median follow-up of 15.4 years, 557 incident T2DM cases have occurred. After adjustment for potential T2DM risk factors and reproductive factors, each additional parity caused a 9% higher risk for incident T2DM. Moreover, compared to women with one parity, those with 3 and ≥ 4 parity had HRs of 1.73 [95% CI: 1.06–2.83] and 2.23 [1.36–3.65], respectively. After further adjustment for body mass index (BMI) and waist circumference, although the HRs were attenuated prominently, parity ≥ 4 was associated with significantly higher risk (HR: 1.72 [1.05–2.83]); even after further adjustment for triglycerides (TG)/ high-density lipoprotein cholesterol (HDL-C), the risk remained marginally significant (HR: 1.64 [1.00–2.70; P value: 0.051]). For the number of live birth, the results were also similar. Moreover, in a sensitivity analysis, when we considered BMI change during follow-up as another covariate, generally, the effect sizes did not change; the trend of HRs across categories of parity number remained marginally significant (P value: 0.064).

Conclusions

During a long-term follow-up, after adjustment for potential T2DM risk factors, reproductive factors, obesity indices, and TG/HDL-C (insulin resistance surrogate), we demonstrated that higher parity/live birth numbers could be associated with increased risk of T2DM development among Iranian women. Moreover, even after further adjustment for BMI change, the suggestive higher risk was still found.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01519-7.

Marginal Food Security Predicts Earlier Age at Menarche Among Girls From the 2009-2014 National Health and Nutrition Examination Surveys

STUDY OBJECTIVE

This study analyzed the relationship between household food security and variation in age at menarche, as well as the connections between food insecurity, nutritional status, and allostatic load, among girls aged 12-15 years from the 2009-2014 United States National Health and Nutrition Examination Survey (NHANES).

METHODS

Data analysis included mean comparisons of age at menarche among household food security groups (high, marginal, low, and very low) as well as categorical variables known to associate with age at menarche (ethnicity, poverty status, body mass index [BMI], allostatic load, and milk consumption). χ² Analyses were used to test the associations between household food security and additional categorical variables. Univariate and multivariate regression models were used to test the relationship between variation in age at menarche and household food security, ethnicity, BMI, and allostatic load categories while controlling for age.

RESULTS

Non-Hispanic Black and Hispanic/Mexican American girls had earlier mean ages at menarche, higher mean BMIs, and disproportionately experienced household food insecurity when compared to non-Hispanic White-identifying girls. In the univariate analyses, marginal household food security, Hispanic/Mexican American and Black ethnicities, overweight and obese BMI categories, and marginal-high allostatic load were each associated with lower age at menarche compared to reference categories. These associations were maintained in the multivariate analysis, although only Hispanic/Mexican American ethnicity predicted earlier menarche when compared to that of non-Hispanic White girls.

CONCLUSIONS

Marginal household food security, particularly for girls who identified as non-White, predicted earlier age at menarche independent of nutritional status and allostatic load. At the same time, having more energetic resources (ie, higher BMI) also significantly predicted earlier menarche.

Joint Associations of Actual Age and Genetically Determined Age at Menarche With Risk of Mortality

IMPORTANCE

Previous studies have shown an association between actual age at menarche and risk of all-cause mortality; however, the results are inconsistent, and no study has analyzed the joint associations between genetic susceptibility and actual age at menarche with the risk of mortality in prospective cohorts.

OBJECTIVES

To investigate joint associations of actual age and genetically determined age at menarche with risk of all-cause mortality.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study was conducted using data from the UK Biobank population across the United Kingdom from March 13, 2006, to October 1, 2010. A total of 264 546 women aged between 39 and 71 years with actual menarcheal age were included in this study; 246 676 of these women had genetic data available. Actual age at menarche was obtained from the touchscreen questionnaire at recruitment from 2006 to 2010. Genetically determined age at menarche was assessed by a genetic risk score. Statistical analysis was performed from August 22 to December 12, 2019.

EXPOSURE

Age at menarche.

MAIN OUTCOMES AND MEASURES

A multivariable Cox proportional hazards regression model was used to assess associations of actual or genetically determined age at menarche with risk of all-cause mortality.

RESULTS

The mean (SD) age of the study population at baseline was 56.4 (8.0) years, and the mean (SD) age at menarche included in the analyses was 13.0 (1.6) years. During a median of 9.0 years (range, 8.3-9.7 years) of follow-up, 7761 deaths were documented among the women with actual age at menarche, and 7054 deaths were documented among the women with genetically determined age at menarche. Both the actual age at menarche and the genetically determined age at menarche showed a U-shaped association with the risk of all-cause mortality (lowest actual age [<12 years] vs reference age [15 years]: hazard ratio [HR], 1.16 [95% CI, 1.07-1.26]; highest actual age [≥16 years] vs reference age [15 years]: HR, 1.17 [95% CI, 1.05-1.31]; P < .001 for quadratic trend; genetic risk score [GRS] of 1 vs reference score [GRS of 4]: HR, 1.10 [95% CI, 1.01-1.19; GRS of 6 vs reference score [GRS of 4]: HR, 1.09 [95% CI, 1.00-1.18]; P = .03 for quadratic trend). Significant interactions were also found between actual age at menarche and genetically determined age at menarche with all-cause mortality (HR of mortality associated with age of menarche <12 year was 1.24 [95% CI, 1.10-1.40] in the GRS of 1 group and 1.44 [95% CI, 1.21-1.72] in the GRS of 6 group; P = .001 for interaction). Women with mismatch of actual age and genetically determined age at menarche had the highest mortality risks; participants with the lowest genetic risk score and the highest age at menarche had an HR of 2.12 (95% CI, 1.58-2.83), and participants with the highest GRS and the lowest age at menarche had an HR of 1.44 (95% CI, 1.21-1.72).

CONCLUSIONS AND RELEVANCE

The results suggest that both actual age and genetically determined age at menarche exhibit U-shaped associations with all-cause mortality. Women with mismatch of actual age and genetically determined age at menarche may have the highest risk of all-cause mortality.

Age at menarche, ideal cardiovascular health metrics, and risk of diabetes in adulthood: Findings from the REACTION study

BACKGROUND

Age at menarche was reported to be associated with the risk of diabetes. However, the impact of ideal cardiovascular health metrics (ICVHMs) on the association between age at menarche and adulthood diabetes risk was unclear.

METHODS

We included 121 431 women from the nationwide, population-based cohort of the REACTION study (Risk Evaluation of Cancers in Chinese Diabetic Individuals: a Longitudinal Study). The diagnosis of diabetes was based on the oral glucose tolerance test (OGTT) and glycosylated hemoglobin (HbA1c) measurement. Logistic regression and multiplicative interaction analysis were conducted to investigate the potential interaction effect between age at menarche and ICVHMs on the development of diabetes.

RESULTS

The multivariable-adjusted odds ratios of diabetes across categories of age at menarche (<14, 14-17, and > 17 years) were 1.22 (95% confidence interval [CI]: 1.17, 1.28), 1.00 (reference), and 0.89 (95% CI: 0.85, 0.93), respectively. In subgroup analysis, significant interactions were detected between total cholesterol/blood pressure levels and age at menarche regarding the risk of diabetes (P for interaction = .0091 and .0019, respectively). The increased risk associated with age at menarche <14 years was observed in participants with three or fewer ICVHMs, but not in women with four or more ICVHMs (P for interaction = .0001).

CONCLUSIONS

Age at menarche was inversely associated with the risk of diabetes in adulthood in Chinese women, and it appeared to be modified by the presence of ICVHMs. Further studies are needed to clarify the precise interrelationship and the generalizability of our results.

What Happens After Menopause? (WHAM): A prospective controlled study of cardiovascular and metabolic risk 12 months after premenopausal risk-reducing bilateral salpingo-oophorectomy

OBJECTIVE

To prospectively measure cardiometabolic risk 12 months after premenopausal risk-reducing bilateral salpingo-oophorectomy (RRBSO) compared to a similar age comparison group, and the effects of Hormone Therapy (HT) on cardiometabolic risk.

METHODS

Prospective observational study of 95 premenopausal women planning RRBSO and 99 comparisons who retained their ovaries. At baseline and 12 months, blood pressure (BP), Body Mass Index (BMI), waist and hip circumference, fasting total, HDL and LDL cholesterol, triglycerides, high-sensitivity C-reactive protein, glucose and insulin were measured and HOMA-IR was calculated. Chi-square tests, t-tests and adjusted logistic regression models were used to compare groups.

RESULTS

Baseline cardiometabolic phenotypes were similar between groups but more RRBSO participants were overweight/obese with higher waist/hip ratios. By 12 months, BP and cardiometabolic phenotypes were largely unchanged. Paired t-tests showed statistically significant increases in BMI (p = 0.037) and weight (p = 0.042) and larger increases in waist circumference (p < 0.001) and waist-hip ratio (p = 0.009) after RRBSO vs comparisons. However, these were not significant when adjusted for baseline values. After RRBSO 60% initiated Hormone Therapy (HT). Paired t-tests demonstrated that non-HT users had a significantly greater mean increase in waist circumference of 4.3 cm (95% CI 2.0-6.5) compared to 1.3 cm in HT users (95% CI -0.2-2.7, p < 0.001), which remained significant when adjusted for baseline values (p = 0.02). At 12 months, mean waist circumference was 2.94 cm greater in non-HT users compared to HT users.

CONCLUSIONS

Cardiometabolic risk markers are largely unchanged 12 months after RRBSO. Hormone Therapy after RRBSO may prevent against an increase in waist circumference.

Age at natural menopause and development of chronic conditions and multimorbidity: results from an Australian prospective cohort

STUDY QUESTION

Is age at natural menopause (ANM) associated with the development of multiple chronic conditions (multimorbidity) in postmenopausal life?

SUMMARY ANSWER

Women with premature menopause experience increased odds of developing individual chronic conditions and multimorbidity.

WHAT IS KNOWN ALREADY

ANM is considered as a marker of age-related morbidity and mortality in postmenopausal life. Multimorbidity affects more than 60% of older women and has been recognized as the most common 'chronic condition'. Few studies have examined the association between ANM and the development of multimorbidity.

STUDY DESIGN, SIZE, DURATION

A prospective national cohort study of 11 258 Australian women, aged 45-50 years in 1996. Women were followed from 1996 to 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Information about ANM and 11 chronic conditions (diabetes, hypertension, heart disease, stroke, arthritis, osteoporosis, asthma, chronic obstructive pulmonary disease, depression, anxiety and breast cancer) were estimated approximately every 3 years. Multimorbidity is defined as 2 or more of these 11 conditions. Generalized estimating equations were used to link the categorical ANM with individual chronic conditions and multimorbidity.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 5107 women reporting ANM, 2.3% experienced premature menopause (≤40 years) and 55.1% developed multimorbidity. Compared with women who experienced menopause at age 50-51 years, women with premature menopause had twice the odds of experiencing multimorbidity by age 60 (OR = 1.98, 95% CI 1.31 to 2.98) and three times the odds of developing multimorbidity in their 60s (OR = 3.03, 95% CI 1.62 to 5.64). Women with premature menopause also experienced higher incidence of most individual chronic conditions.

LIMITATIONS, REASONS FOR CAUTION

The main limitation of this study was the use of self-reported data, but with repeated assessments from prospective study design and the validity of most of the chronic conditions from hospital data, the potential for non-differential misclassification is minimized.

WIDE IMPLICATIONS OF THE FINDINGS

To our knowledge, this is the first study to assess the association of premature menopause and development of multimorbidity in a larger national cohort of mid-aged women. Health professionals should consider comprehensive screening and assessment of risk factors for multimorbidity when treating women who experienced premature menopause.

STUDY FUNDING/COMPETING INTEREST(S)

The Australian Longitudinal Study on Women's Health was supported by the Australian Government Department of Health. X.X. is funded by an International Postgraduate Research Scholarship from the Australian government and a UQ Centennial Scholarship from The University of Queensland. G.D.M. is supported by the National Health and Medical Research Council Principal Research Fellowship (APP1121844). None of the authors has any conflicts of interest to declare.

Age at menarche and risk of vasomotor menopausal symptoms: a pooled analysis of six studies

OBJECTIVE

To examine the association between age at menarche and risk of vasomotor menopausal symptoms (VMS) and whether midlife body mass index (BMI) modified the association.

DESIGN

A pooled analysis of six cohort studies.

SETTING

The International collaboration on the Life course Approach to reproductive health and Chronic disease Events (InterLACE).

POPULATION

18 555 women from the UK, USA and Australia.

METHODS

VMS frequency data (never, rarely, sometimes and often) were harmonised from two studies (n = 13 602); severity data (never, mild, moderate and severe) from the other four studies (n = 4953). Multinominal logistic regression models were used to estimate relative risk ratios (RRRs) and 95% CIs adjusted for confounders and incorporated study as random effects.

MAIN OUTCOME MEASURES

Hot flushes and night sweats.

RESULTS

Frequency data showed that early menarche ≤11 years was associated with an increased risk of 'often' hot flushes (RRR 1.48, 95% CI 1.24-1.76) and night sweats (RRR 1.59, 95% CI 1.49-1.70) compared with menarche at ≥14 years. Severity data showed similar results, but appeared less conclusive, with RRRs of 1.16 (95% CI 0.94-1.42) and 1.27 (95% CI 1.01-1.58) for 'severe' hot flushes and night sweats, respectively. BMI significantly modified the association as the risk associated with early menarche and 'often' VMS was stronger among women who were overweight or obese than those of normal weight, while this gradient across BMI categories was not as strong with the risk of 'severe' VMS.

CONCLUSIONS

Early age at menarche is a risk factor for VMS, particularly for frequent VMS, but midlife BMI may play an important role in modifying this risk.

TWEETABLE ABSTRACT

Overweight and obesity exacerbate the risk of vasomotor symptoms associated with early menarche.

Reproductive health in women with type 2 diabetes mellitus

As type 2 diabetes mellitus (T2DM) reaches epidemic proportions in the developed world and the age at diagnosis decreases, more women of reproductive age are being affected. In this article, we provide a synoptic view on potential mechanisms and relevant factors underlying menstrual cycle disorders and fertility issues in women with T2DM. The article discusses the function of the hypothalamic-pituitary-ovarian (HPO) axis, the central role of the hypothalamus in the homeostasis of this system, the central modulators of the axis, and the peripheral metabolic signals involved in neuroendocrine control of reproduction. The available literature on the relationship between T2DM and the female reproductive lifespan, menstrual cycle disorders, fertility issues, and gestational health in women with T2DM are also discussed. The data so far indicate that there is a "U-shaped" relationship between menarche, menopause, and T2DM, both early and late menarche/menopause being risk factors for T2DM. Hyperglycemia and its consequences may be responsible for the effects of T2DM on reproductive health in women, but the exact mechanisms are not as yet fully understood; thus, more studies are needed in order to identify factors causing disruption of the HPO axis.

Association between reproductive years and insulin resistance in middle-aged and older women: A 10-year prospective cohort study

OBJECTIVES

We hypothesized that reproductive years, a marker of total estrogen exposure, may play an important role in insulin resistance.

STUDY DESIGN

A total of 3327 middle-aged and older women (age range 40-69 years) from the Korean Genome and Epidemiology Study were included in this large prospective cohort study with a mean follow-up of 10.8 years.

MAIN OUTCOME MEASURES

Insulin resistance and sensitivity were calculated using the homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI). A linear mixed model for a repeated-measures covariance pattern with unstructured covariance within participants was used to assess longitudinal associations between baseline reproductive years and subsequent changes in HOMA-IR and QUICKI. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for new-onset insulin resistance according to quartiles of reproductive years.

RESULTS

Changes in HOMA-IR were significantly greater in Q1 (fewest reproductive years) than in Q4 (most reproductive years) (beta[SE] = 0.038[0.016]; p-value = 0.022), while changes in QUICKI were significantly smaller in Q1 than in Q4 (beta[SE] = -0.001[0.000]; p-value = 0.048) after adjusting for possible confounders over time. Compared with Q1, HRs (95 % CIs) for the incidence of new-onset insulin resistance were 0.807 (0.654-0.994) for Q2, 0.793 (0.645-0.974) for Q3, and 0.770 (0.622-0.953) for Q4 after adjusting for possible confounders.

CONCLUSION

A short reproductive period is associated with elevated levels on the HOMA-IR and decreased levels on the QUICKI over time. The lowest quartile of reproductive years was significantly associated with a higher risk of new-onset insulin resistance.

Infertility, Gravidity, and Risk Of Diabetes among High-Risk Women in the Diabetes Prevention Program Outcomes Study

OBJECTIVE

The extent to which infertility and pregnancy independently increase risk of diabetes and subclinical atherosclerosis is not known.

RESEARCH DESIGN AND METHODS

We conducted a secondary analysis of Diabetes Prevention Program (DPP) and the DPP Outcomes Study over a 15-year period. We included women who answered questions about gravidity and infertility at baseline (n = 2085). Infertility was defined as > 1 year of unsuccessful attempts to conceive; thus, women could have histories of infertility as well as pregnancy. Risk of diabetes associated with gravidity and infertility was calculated using Cox proportional hazards models adjusting for age, race/ethnicity, treatment arm, body mass index, and pregnancy during the study. Among women who underwent assessment of coronary artery calcification (CAC) (n = 1337), odds of CAC were calculated using logistic regression models with similar covariates.

RESULTS

Among premenopausal women (n = 1075), women with histories of pregnancy and infertility (n = 147; hazard ratio [HR] 1.80; 95% confidence interval [CI] 1.30, 2.49) and women with histories of pregnancy without infertility (n = 736; HR 1.49; 95% CI 1.15, 1.93) had greater diabetes risk than nulligravid women without infertility (n = 173). Premenopausal nulligravid women with histories of infertility had a non-significant elevation in risk, although the number of these women was small (n = 19; HR 1.63; 95% CI 0.88, 3.03). Associations were not observed among postmenopausal women (n = 1010). No associations were observed between infertility or pregnancy with CAC.

CONCLUSIONS

Pregnancy, particularly combined with a history of infertility, confers increased risk of diabetes but not CAC among glucose-intolerant premenopausal women.

Association of puberty timing with type 2 diabetes: A systematic review and meta-analysis

BACKGROUND

Emerging studies have investigated the association between puberty timing, particularly age at menarche (AAM), and type 2 diabetes. However, whether this association is independent of adiposity is unclear. We aimed to systematically review published evidence on the association between puberty timing and type 2 diabetes (T2D) or impaired glucose tolerance (IGT), with and without adjustment for adiposity, and to estimate the potential contribution of puberty timing to the burden of T2D in the United Kingdom (UK).

METHODS AND FINDINGS

We searched PubMed, Medline, and Embase databases for publications until February 2019 on the timing of any secondary sexual characteristic in boys or girls in relation to T2D/IGT. Inverse-variance-weighted random-effects meta-analysis was used to pool reported estimates, and meta-regression was used to explore sources of heterogeneity. Twenty-eight observational studies were identified. All assessed AAM in women (combined N = 1,228,306); only 1 study additionally included men. In models without adjustment for adult adiposity, T2D/IGT risk was lower per year later AAM (relative risk [RR] = 0.91, 95% CI 0.89-0.93, p < 0.001, 11 estimates, n = 833,529, I2 = 85.4%) and higher for early versus later menarche (RR = 1.39, 95% CI 1.25-1.55, p < 0.001, 23 estimates, n = 1,185,444, I2 = 87.8%). Associations were weaker but still evident in models adjusted for adiposity (AAM: RR = 0.97 per year, 95% CI 0.95-0.98, p < 0.001, 12 estimates, n = 852,268, I2 = 51.8%; early menarche: RR = 1.19, 95% CI 1.11-1.28, p < 0.001, 21 estimates, n = 890,583, I2 = 68.1%). Associations were stronger among white than Asian women, and in populations with earlier average AAM. The estimated population attributable risk of T2D in white UK women due to early menarche unadjusted and adjusted for adiposity was 12.6% (95% CI 11.0-14.3) and 5.1% (95% CI 3.6-6.7), respectively. Findings in this study are limited by residual and unmeasured confounding, and self-reported AAM.

CONCLUSIONS

Earlier AAM is consistently associated with higher T2D/IGT risk, independent of adiposity. More importantly, this research has identified that a substantial proportion of T2D in women is related to early menarche, which would be expected to increase in light of global secular trends towards earlier puberty timing. These findings highlight the need to identify the underlying mechanisms linking early menarche to T2D/IGT risk.

Association of age at menopause and type 2 diabetes: A systematic review and dose-response meta-analysis of cohort studies

AIMS

Early age at menopause has been associated with increased incidence of type 2 diabetes mellitus (T2DM), but the quantitative association between age at menopause and T2DM was unclear. We performed a meta-analysis to assess the dose-response association between age at menopause and T2DM.

METHODS

PubMed, Embase and Web of Science were searched up to January 5, 2019 for cohort studies that evaluated the association of age at menopause and risk of T2DM. Relative risks (RRs) and 95% confidence intervals (95% CIs) were pooled by using the random-effects models. Restricted cubic spline model was used to evaluate the liner or nonlinear relation.

RESULTS

We identified 6 studies for the meta-analysis (267,284 women and 19,654 cases of T2DM). The pooled RR was 0.64 (95% CI 0.44-0.94) comparing the latest with the earliest category of age at menopause. The risk of T2DM was reduced by 10% (RR=0.90, 95% CI, 0.84-0.98) with each 5-year increment in age at menopause. We found an inverse linear association between age at menopause and T2DM.

CONCLUSIONS

Our results suggest that later age at menopause was associated with lower risk of T2DM.