Age at menopause and all-cause and cause-specific dementia: a prospective analysis of the UK Biobank cohort

STUDY QUESTION

Are there associations between natural or surgical menopause and incident dementia by age at menopause?

SUMMARY ANSWER

Compared to age at menopause of 46-50 years, earlier natural menopause (≤40 and 41-45 years) was related to higher risk of all-cause dementia, while a U-shape relationship was observed between age at surgical menopause and risk of dementia.

WHAT IS KNOWN ALREADY

Menopause marks the end of female reproductive period. Age at menopause reflects the length of exposure to endogenous estrogen. Evidence on the association between age at natural, surgical menopause, and risk of dementia has been inconsistent.

STUDY DESIGN, SIZE, DURATION

A population-based cohort study involving 160 080 women who participated in the UK Biobank study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with no dementia at baseline, and had no missing data on key exposure variables and covariates were included. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs on the association of categorical menopause age with incident all-cause dementia, Alzheimer's disease (AD) and vascular dementia (VD). Restricted cubic splines were used to model the non-linear relationship between continuous age at natural, surgical menopause, and risk of dementia. In addition, we analyzed the interaction effect of ever-used menopausal hormone therapy (MHT) at baseline, income level, leisure activities, and age at menopause on risk of dementia.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to women with age at menopause of 46-50 years, women with earlier natural menopause younger than 40 years (1.36, 1.01-1.83) and 41-45 years (1.19, 1.03-1.39) had a higher risk of all-cause dementia, while late natural menopause >55 years was linked to lower risk of dementia (0.83, 0.71-0.98). Compared to natural menopause, surgical menopause was associated with 10% higher risk of dementia (1.10, 0.98-1.24). A U-shape relationship was observed between surgical menopause and risk of dementia. Women with surgical menopause before age 40 years (1.94, 1.38-2.73) and after age 55 years (1.65, 1.21-2.24) were both linked to increased risk of all-cause dementia. Women with early natural menopause without ever taking MHT at baseline had an increased risk of AD. Also, in each categorized age at the menopause level, higher income level or higher number of leisure activities was linked to a lowers risk of dementia.

LIMITATIONS, REASONS FOR CAUTION

Menopausal age was based on women's self-report, which might cause recall bias.

WIDER IMPLICATION OF THE FINDINGS

Women who experienced natural menopause or had surgical menopause at an earlier age need close monitoring and engagement for preventive health measures to delay the development of dementia.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the Start-up Foundation for Scientific Research in Shandong University (202099000066), Science Fund Program for Excellent Young Scholars of Shandong Provence (Overseas) (2022HWYQ-030), and the National Natural Science Foundation of China (82273702). There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Is there a link between infertility, miscarriage, stillbirth, and premature or early menopause? Results from pooled analyses of 9 cohort studies

BACKGROUND

Some reproductive factors (such as age at menarche and parity) have been shown to be associated with age at natural menopause, but there has been little quantitative analysis of the association between infertility, miscarriage, stillbirth, and premature (<40 years) or early menopause (40-44 years). In addition, it has been unknown whether the association differs between Asian and non-Asian women, although the age at natural menopause is younger among Asian women.

OBJECTIVE

This study aimed to investigate the association of infertility, miscarriage, and stillbirth with age at natural menopause, and whether the association differed by race (Asian and non-Asian).

STUDY DESIGN

This was a pooled individual participant data analysis from 9 observational studies contributing to the InterLACE consortium. Naturally postmenopausal women with data on at least 1 of the reproductive factors (ie, infertility, miscarriage, and stillbirth), age at menopause, and confounders (ie, race, education level, age at menarche, body mass index, and smoking status) were included. A multinomial logistic regression model was used to estimate relative risk ratios and 95% confidence intervals for the association of infertility, miscarriage, and stillbirth with premature or early menopause, adjusting for confounders. Between-study difference and within-study correlation were taken into account by including study as a fixed effect and indicating study as a cluster variable. We also examined the association with number of miscarriages (0, 1, 2, ≥3) and stillbirths (0, 1, ≥2), and tested whether the strength of association differed between Asian and non-Asian women.

RESULTS

A total of 303,594 postmenopausal women were included. Their median age at natural menopause was 50.0 years (interquartile range, 47.0-52.0). The percentages of women with premature and early menopause were 2.1% and 8.4%, respectively. The relative risk ratios (95% confidence intervals) of premature and early menopause were 2.72 (1.77-4.17) and 1.42 (1.15-1.74) for women with infertility; 1.31 (1.08-1.59) and 1.37 (1.14-1.65) for women with recurrent miscarriages; and 1.54 (1.52-1.56) and 1.39 (1.35-1.43) for women with recurrent stillbirths. Asian women with infertility, recurrent miscarriages (≥3), or recurrent stillbirths (≥2) had higher risk of premature and early menopause compared with non-Asian women with the same reproductive history.

CONCLUSION

Histories of infertility and recurrent miscarriages and stillbirths were associated with higher risk of premature and early menopause, and the associations differed by race, with stronger associations for Asian women with such reproductive history.

The Interplay Among Natural Menopause, Insomnia, and Cognitive Health: A Population-Based Study

PURPOSE

The interrelationships among age at menopause, sleep, and brain health have been insufficiently studied. This study sought to examine the influence of age at natural menopause and insomnia symptoms on long-term cognitive function among US women.

PATIENTS AND METHODS

Our study included a nationally representative cohort of US adults age 50+ from the Health and Retirement Study (2008-2018). We restricted this cohort to 5880 women age 50+, from a diverse racial and ethnic groups. Age at menopause was retrieved from baseline (2008) for women having natural menopause. Five questions were used to identify women with insomnia symptoms (2010 and 2012): trouble falling asleep, nighttime awakenings, early morning awakenings, feelings of nonrestorative sleep, and use of sleep aids. A battery of four neuropsychological tests was conducted biennially (years) to evaluate cognitive function. Longitudinal associations between age at natural menopause and cognitive function were estimated with mixed effects models with a random intercept. Insomnia symptoms were examined as potential mediators or modifiers in the pathway between age at menopause and cognition.

RESULTS

One year earlier in age at menopause was associated with a 0.49 lower mean in composite cognitive score, in any given survey year (adjusted p = 0.002). Earlier age at menopause was associated with higher risk of developing insomnia symptoms (eg, trouble falling asleep OR = 0.97; 95% CI: 0.96, 0.99), and insomnia symptoms were associated with worse cognitive performance (eg, trouble falling asleep, beta = -0.5, p-value = 0.02). Therefore, insomnia symptoms could potentially mediate the association between age at natural menopause and cognition.

CONCLUSION

Earlier age at menopause is associated with a lower score in cognitive performance. This association may be mediated by insomnia symptoms. Our findings spotlight that among women who experience early menopause, there is the need for studies of sleep-based interventions to mitigate cognitive decline.

Menopause, hysterectomy, menopausal hormone therapy and cause-specific mortality: cohort study of UK Biobank participants

STUDY QUESTION

What is the association between menopausal hormone therapy (MHT) and cause-specific mortality?

SUMMARY ANSWER

Self-reported MHT use following early natural menopause, surgical menopause or premenopausal hysterectomy is associated with a lower risk of breast cancer mortality and is not consistently associated with the risk of mortality from cardiovascular disease or other causes.

WHAT IS KNOWN ALREADY

Evidence from the Women's Health Initiative randomized controlled trials showed that the use of estrogen alone is not associated with the risk of cardiovascular mortality and is associated with a lower risk of breast cancer mortality, but evidence from the Million Women Study showed that use of estrogen alone is associated with a higher risk of breast cancer mortality.

STUDY DESIGN, SIZE, DURATION

Cohort study (the UK Biobank), 178 379 women, recruited in 2006-2010.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Postmenopausal women who had reported age at menopause (natural or surgical) or hysterectomy, and information on MHT and cause-specific mortality. Age at natural menopause, age at surgical menopause, age at hysterectomy and MHT were exposures of interest. Natural menopause was defined as spontaneous cessation of menstruation for 12 months with no previous hysterectomy or oophorectomy. Surgical menopause was defined as the removal of both ovaries prior to natural menopause. Hysterectomy was defined as removal of the uterus before natural menopause without bilateral oophorectomy. The study outcome was cause-specific mortality.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 178 379 women included, 136 790 had natural menopause, 17 569 had surgical menopause and 24 020 had hysterectomy alone. Compared with women with natural menopause at the age of 50-52 years, women with natural menopause before 40 years (hazard ratio (HR): 2.38, 95% CI: 1.64, 3.45) or hysterectomy before 40 years (HR: 1.60, 95% CI: 1.23, 2.07) had a higher risk of cardiovascular mortality but not cancer mortality. MHT use was associated with a lower risk of breast cancer mortality following surgical menopause before 45 years (HR: 0.17, 95% CI: 0.08, 0.36), at 45-49 years (HR: 0.15, 95% CI: 0.07, 0.35) or at ≥50 years (HR: 0.28, 95% CI: 0.13, 0.63), and the association between MHT use and the risk of breast cancer mortality did not differ by MHT use duration (<6 or 6-20 years). MHT use was also associated with a lower risk of breast cancer mortality following natural menopause before 45 years (HR: 0.59, 95% CI: 0.36, 0.95) or hysterectomy before 45 years (HR: 0.49, 95% CI: 0.32, 0.74).

LIMITATIONS, REASONS FOR CAUTION

Self-reported data on age at natural menopause, age at surgical menopause, age at hysterectomy and MHT.

WIDER IMPLICATIONS OF THE FINDINGS

The current international guidelines recommend women with early menopause to use MHT until the average age at menopause. Our findings support this recommendation.

STUDY FUNDING/COMPETING INTEREST(S)

This project is funded by the Australian National Health and Medical Research Council (NHMRC) (grant numbers APP1027196 and APP1153420). G.D.M. is supported by NHMRC Principal Research Fellowship (APP1121844), and M.H. is supported by an NHMRC Investigator Grant (APP1193838). There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

The relevance of the endocrine condition in microglia morphology and dendrite complexity of doublecortin-associated neurons in young adult and middle-aged female rats exposed to acute stress

Menopause, natural or surgical, might facilitate the onset of psychiatric pathologies. Some reports suggest that their severity could increase if the decline of ovarian hormones occurs abruptly and before natural endocrine senescence. Therefore, we compared the effects of ovariectomy on microglia's morphological alterations, the complexity of newborn neurons, and the animal's ability to cope with stress. Young adult (3 months) and middle-aged (15 months) female Wistar rats were subjected to an ovariectomy (OVX) or were sham-operated. After 3 weeks, animals were assigned to one of the following independent groups: (1) young adult OVX + no stress; (2) young adult sham + no stress; (3) young adult OVX + stress; (4) young adult sham + stress; (5) middle-aged OVX + no stress; (6) middle-aged sham + no stress; (7) middle-aged OVX + stress; (8) middle-aged sham + stress. Acute stress was induced by forced swimming test (FST) exposure. Immobility behavior was scored during FST and 30 min after; animals were euthanized, their brains collected and prepared for immunohistochemical detection of Iba-1 to analyze morphological alterations in microglia, and doublecortin (DCX) detection to evaluate the dendrite complexity of newborn neurons. OVX increased immobility behavior, induced microglia morphological alterations, and reduced dendrite complexity of newborn neurons in young adult rats. FST further increased this effect. In middle-aged rats, the main effects were related to the aging process without OVX or stress exposure. In conclusion, surgical menopause favors in young adult rats, but not in middle-aged, the vulnerability to develop immobility behavior, retracted morphology of microglial cells, and decreased dendrite complexity of newborn neurons.

Association of oral contraceptives and tubal ligation with risk of early natural menopause

STUDY QUESTION

What is the association of oral contraceptives (OCs) and tubal ligation (TL) with early natural menopause?

SUMMARY ANSWER

We did not observe an association of OC use with risk of early natural menopause; however, TL was associated with a modestly higher risk.

WHAT IS KNOWN ALREADY

OCs manipulate hormone levels, prevent ovulation, and may modify the rate of follicular atresia, while TL may disrupt the blood supply to the ovaries. These mechanisms may be associated with risk of early menopause, a condition associated with increased risk of cardiovascular disease and other adverse health outcomes.

STUDY DESIGN, SIZE, DURATION

We examined the association of OC use and TL with natural menopause before the age of 45 years in a population-based study within the prospective Nurses' Health Study II (NHSII) cohort. Participants were followed from 1989 to 2017 and response rates were 85-90% for each cycle.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants included 106 633 NHSII members who were premenopausal and aged 25-42 years at baseline. Use, duration and type of OC, and TL were measured at baseline and every 2 years. Menopause status and age were assessed every 2 years. Follow-up continued until early menopause, age 45 years, hysterectomy, oophorectomy, death, cancer diagnosis, or loss to follow-up. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs adjusted for lifestyle, dietary, and reproductive factors.

MAIN RESULTS AND THE ROLE OF CHANCE

Over 1.6 million person-years, 2579 members of the analytic cohort experienced early natural menopause. In multivariable models, the duration, timing, and type of OC use were not associated with risk of early menopause. For example, compared with women who never used OCs, those reporting 120+ months of OC use had an HR for early menopause of 1.01 (95% CI, 0.87-1.17; P for trend=0.71). TL was associated with increased risk of early menopause (HR = 1.17, 95% CI, 1.06-1.28).

LIMITATIONS, REASONS FOR CAUTION

Our study population is homogenous with respect to race and ethnicity. Additional evaluation of these relations in more diverse populations is important.

WIDER IMPLICATIONS OF THE FINDINGS

To our knowledge, this is the largest study examining the association of OC use and TL with early natural menopause to date. While TL was associated with a modest higher risk of early menopause, our findings do not support any material hazard or benefit for the use of OCs.

STUDY FUNDING/COMPETING INTEREST(S)

The study was sponsored by UO1CA176726 and R01HD078517 from the National Institutes of Health and Department of Health and Human Services. The work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors have no competing interests to report.

TRIAL REGISTRATION NUMBER

N/A.

Associations of Perfluoroalkyl Substances with Incident Natural Menopause: The Study of Women's Health Across the Nation

CONTEXT

Previous epidemiologic studies of per- and polyfluoroalkyl substances (PFASs) and menopausal timing conducted in cross-sectional settings were limited by reverse causation because PFAS serum concentrations increase after menopause.

OBJECTIVES

To investigate associations between perfluoroalkyl substances and incident natural menopause.

DESIGN AND SETTING

A prospective cohort of midlife women, the Study of Women's Health Across the Nation, 1999-2017.

PARTICIPANTS

1120 multiracial/ethnic premenopausal women aged 45-56 years.

METHODS

Serum concentrations of perfluoroalkyls were quantified by high-performance liquid chromatography isotope dilution tandem mass spectrometry. Natural menopause was defined as the bleeding episode prior to at least 12 months of amenorrhea not due to surgery or hormone use. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Participants contributed 5466 person-years of follow-up, and 578 had incident natural menopause. Compared with the lowest tertile, women at the highest tertile of baseline serum concentrations had adjusted HR for natural menopause of 1.26 (95% CI: 1.02-1.57) for n-perfluorooctane sulfonic acid (n-PFOS) (Ptrend = .03), 1.27 (95% CI: 1.01-1.59) for branched-PFOS (Ptrend = .03), and 1.31 (95% CI: 1.04-1.65) for n-perfluorooctanoic acid (Ptrend = .01). Women were classified into four clusters based on their overall PFAS concentrations as mixtures: low, low-medium, medium-high, and high. Compared with the low cluster, the high cluster had a HR of 1.63 (95% CI: 1.08-2.45), which is equivalent to 2.0 years earlier median time to natural menopause.

CONCLUSION

This study suggests that select PFAS serum concentrations are associated with earlier natural menopause, a risk factor for adverse health outcomes in later life.

Type of menopause, age of menopause and variations in the risk of incident cardiovascular disease: pooled analysis of individual data from 10 international studies

STUDY QUESTION

How does the risk of cardiovascular disease (CVD) vary with type and age of menopause?

SUMMARY ANSWER

Earlier surgical menopause (e.g. <45 years) poses additional increased risk of incident CVD events, compared to women with natural menopause at the same age, and HRT use reduced the risk of CVD in women with early surgical menopause.

WHAT IS KNOWN ALREADY

Earlier age at menopause has been linked to an increased risk of CVD mortality and all-cause mortality, but the extent that this risk of CVD varies by type of menopause and the role of postmenopausal HRT use in reducing this risk is unclear.

STUDY DESIGN, SIZE, DURATION

Pooled individual-level data of 203 767 postmenopausal women from 10 observational studies that contribute to the International collaboration for a Life course Approach to reproductive health and Chronic disease Events (InterLACE) consortium were included in the analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Postmenopausal women who had reported menopause (type and age of menopause) and information on non-fatal CVD events were included. Type of menopause (natural menopause and surgical menopause) and age at menopause (categorised as <35, 35-39, 40-44, 45-49, 50-54 and ≥55 years) were exposures of interest. Natural menopause was defined as absence of menstruation over a period of 12 months (no hysterectomy and/or oophorectomy) and surgical menopause as removal of both ovaries. The study outcome was the first non-fatal CVD (defined as either incident coronary heart disease (CHD) or stroke) event ascertained from hospital medical records or self-reported. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CI for non-fatal CVD events associated with natural menopause and surgical menopause.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with natural menopause, surgical menopause was associated with over 20% higher risk of CVD (HR 1.22, 95% CI 1.16-1.28). After the stratified analysis by age at menopause, a graded relationship for incident CVD was observed with lower age at menopause in both types of natural and surgical menopause. There was also a significant interaction between type of menopause and age at menopause (P < 0.001). Compared with natural menopause at 50-54 years, women with surgical menopause before 35 (2.55, 2.22-2.94) and 35-39 years (1.91, 1.71-2.14) had higher risk of CVD than those with natural menopause (1.59, 1.23-2.05 and 1.51, 1.33-1.72, respectively). Women who experienced surgical menopause at earlier age (<50 years) and took HRT had lower risk of incident CHD than those who were not users of HRT.

LIMITATIONS, REASONS FOR CAUTION

Self-reported data on type and age of menopause, no information on indication for the surgery (e.g. endometriosis and fibroids) and the exclusion of fatal CVD events may bias our results.

WIDER IMPLICATIONS OF THE FINDINGS

In clinical practice, women who experienced natural menopause or had surgical menopause at an earlier age need close monitoring and engagement for preventive health measures and early diagnosis of CVD. Our findings also suggested that timing of menopause should be considered as an important factor in risk assessment of CVD for women. The findings on CVD lend some support to the position that elective bilateral oophorectomy (surgical menopause) at hysterectomy for benign diseases should be discouraged based on an increased risk of CVD.

STUDY FUNDING/COMPETING INTEREST(S)

InterLACE project is funded by the Australian National Health and Medical Research Council project grant (APP1027196). GDM is supported by Australian National Health and Medical Research Council Principal Research Fellowship (APP1121844). There are no competing interests.

Chinese women with 29-30 FMR1 CGG repeats have an earlier menopause

Purpose: A strong, well-established non-linear relationship exists between fragile X mental retardation (FMR1) premutation and menopausal age. The aim of this study is to evaluate whether this relationship continues into the normal CGG repeat range.Methods: FMR1 CGG repeats of 111 Chinese postmenopausal women from a prospective cohort and the relationship with age at menopause were analyzed. Associations of FMR1 genotypes with annually measured estradiol and follicle stimulating hormone (FSH) levels were also assessed.Results: One premutation and two intermediate carriers were identified, with a prevalence of 0.90% and 1.80%, respectively. The age at menopause differed with statistical significance (p = 0.007) between women carrying bi-allelic 29-30 repeats (49.66 ± 3.26 years) and those carrying a different number of repeats (51.26 ± 2.74 years). Age at menopause among subgroups (≤28, 29-30, and ≥31 repeats) of alleles 1 and 2 were also different (p = 0.014, p = 0.044). FSH trajectories to final menstrual period differed between women with the bi-allelic 29-30 repeats and others (p = 0.019).Conclusions: Women with 29-30 FMR1 CGG repeats may experience menopause approximately 2 years earlier than those carrying ≤28 or ≥31 CGG repeats, and have a longer FSH fluctuant period.

Dietary intake and age at natural menopause: results from the UK Women's Cohort Study

BACKGROUND

Age at natural menopause is a matter of concern for women of reproductive age as both an early or late menopause may have implications for health outcomes.

METHODS

Study participants were women aged 40-65 years who had experienced a natural menopause from the UK Women's Cohort Study between baseline and first follow-up. Natural menopause was defined as the permanent cessation of menstrual periods for at least 12 consecutive months. A food frequency questionnaire was used to estimate diet at baseline. Reproductive history of participants was also recorded. Regression modelling, adjusting for confounders, was used to assess associations between diet and age at natural menopause.

RESULTS

During the 4-year follow-up period, 914 women experienced a natural menopause. A high intake of oily fish and fresh legumes were associated with delayed onset of natural menopause by 3.3 years per portion/day (99% CI 0.8 to 5.8) and 0.9 years per portion/day (99% CI 0.0 to 1.8), respectively. Refined pasta and rice was associated with earlier menopause (per portion/day: -1.5 years, 99% CI -2.8 to -0.2). A higher intake of vitamin B6 (per mg/day: 0.6 years, 99% CI 0.1 to 1.2) and zinc (per mg/day: 0.3 years, 99% CI -0.0 to 0.6) was also associated with later age at menopause. Stratification by age at baseline led to attenuated results.

CONCLUSION

Our results suggest that some food groups (oily fish, fresh legumes, refined pasta and rice) and specific nutrients are individually predictive of age at natural menopause.

Natural menopause among women below 50 years in India: A population-based study

BACKGROUND & OBJECTIVES

The age at which menopause naturally occurs may reflect nutritional and environmental circumstances as well as genetic factors. In this study we examined natural menopause as a marker of women's health at the population level in India and in some major States.

METHODS

Data from the Indian District Level Household Survey (DLHS) carried out during 2007-2008 covering 643,944 ever-married women aged 15-49 yr were used; women of older ages were not included in this survey. Since not all women in this age group had achieved natural menopause at the time of survey, Cox proportional hazard regression models were employed to obtain the median age of women reporting a natural menopause, excluding those who underwent hysterectomy. Hazard ratios (HRs) were estimated for key socio-economic and reproductive variables that could potentially affect the age at natural menopause <40 yr.

RESULTS

Overall, menopause prior to age 40 was reported by approximately 1.5 per cent of women. In the national data set, significant associations with age at natural menopause were identified with marriage breakdown or widowhood, poverty, Muslim religious affiliation, 'scheduled caste' status, not having received schooling, rural residence, having never used contraceptive pills, not been sterilized or had an abortion, low parity and residence in the western region. Within data from five selected States examined separately, the strength of these associations varied.

INTERPRETATION & CONCLUSIONS

Associations of natural menopause with sociocultural, family planning and demographic variables were noted. Most importantly, there was an association with poverty that would require further investigation as to causality. The proportion of women experiencing early menopause may represent a useful overall indicator of women's health. The data are reassuring with regard to possible late effects of sterilization on ovarian function.

Evaluation of cardiovascular disease risk in women with surgically induced menopause

OBJECTIVE

This study evaluates cardiovascular disease (CVD) risk among women undergoing natural menopause or surgically induced menopause through the measurement of serum growth differentiation factor-15 (GDF-15), B-type natriuretic peptide (BNP), ischemia modified albumin (IMA), total cholesterol, LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), triglyceride, fibrinogen, and C-reactive protein (CRP).

MATERIALS AND METHODS

The study included women with surgically induced menopause (n = 50) and women undergoing natural menopause (n = 50). The two study groups were matched according to age, body mass index, menopause duration. GDF-15, BNP, IMA, total cholesterol, LDL-C, HDL-C, triglyceride, fibrinogen, and CRP were measured.

RESULTS

There was no significant difference in GDF-15, BNP, IMA, total cholesterol, LDL-C, HDL-C, triglyceride, fibrinogen, and CRP results between the two groups.

CONCLUSION

We conclude that there is no increase in CVD risk among women aged 40-50 with surgically induced menopause relative to matched control subjects undergoing normal age-related menopause.

Age at menopause in women with type 1 diabetes mellitus: the OVADIA study

STUDY QUESTION

Is type 1 diabetes a determinant of advanced ovarian ageing, resulting in an early age at natural menopause?

SUMMARY ANSWER

No clear evidence was provided that type 1 diabetes is a determinant of accelerated ovarian ageing resulting in an early menopause.

WHAT IS KNOWN ALREADY

The association between type 1 diabetes and early menopause has been examined previously with inconsistent results.

STUDY DESIGN, SIZE, DURATION

A cross-sectional study was performed in 140 post-menopausal women with, and 5426 post-menopausal women without, diabetes.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Both women with and without diabetes had experienced natural menopause. Study participants filled out a standardized questionnaire including report of their age at last menstrual period. Differences in menopausal age were analysed using linear regression analyses, with adjustment for possible confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

Mean age at natural menopause was 49.8 ± 4.7 years in women with type 1 diabetes and 49.8 ± 4.1 in women without diabetes. Linear regression analyses showed that type 1 diabetes was not associated with an earlier menopause compared with the reference group without diabetes, after adjustment for age, smoking history and parity (difference in age at menopause between women with type 1 diabetes and reference group 0.34 years, 95% confidence interval -0.34, 1.01).

LIMITATIONS, REASON FOR CAUTION

Age at menopause was self-reported and assessed retrospectively. We had no information regarding microvascular complications therefore a possible association between vascular health and menopausal age could not be investigated.

WIDER IMPLICATIONS OF THE FINDINGS

It has been hypothesized that the possible mechanism behind an accelerated ovarian ageing process in type 1 diabetes is prolonged poor glycaemic control and subsequent effects on vascular health. The improved glycaemic control during the last decades may have prevented vascular damage from occurring to an extent that would affect organ function. Nevertheless, the present findings are reassuring for reproductive health prospects in women with type 1 diabetes.

Lifestyle and dietary factors determine age at natural menopause

A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to identify the modifiable risk factors like diet and lifestyle changes. Delayed menopause is associated with increased risk of endometrial and breast cancer, while early ANM enhances the risk for cardiovascular diseases and osteoporosis. The correlation between diet and ANM has not been extensively studied; however, whatever studies have been done till now point towards role of high intake of total calories, fruits, and proteins in delaying the ANM, while high polyunsaturated fat intake accelerates it. The role of dietary soy, total fat, saturated fat, red meat, and dietary fiber in determining the ANM has been controversial and needs further studies to substantiate it. The lifestyle factors like current smoking and vigorous exercise have been significantly associated with early menopause, while moderate alcohol consumption delays the ANM. Large prospective studies are needed to study the association of ANM and other modifiable factors like passive smoking fish consumption, soy, and various types of tea. The knowledge of modifiable determinants of ANM can help in setting up menopausal clinics and initiating health programs specially in developing countries.

Decreased oxidant profile and increased antioxidant capacity in naturally postmenopausal women

Recent works have shown a dual side of estrogens, and research on the relationship between oxidative stress and menopausal status remains unclear and has produced controversial results. In this work, we aimed to evaluate by sensitive methods the oxidant and antioxidant changes that develop after natural menopause. Thirty premenopausal and 28 naturally postmenopausal women volunteered for this study. Blood was collected and plasma used. 17-OH estradiol levels in plasma were estimated. Plasma levels of advanced oxidation protein products (AOPP), lipid peroxidation products (such as hydroperoxides and malondialdehyde (MDA)), and nitrites were measured, and total radical antioxidant parameter testing was performed to determine the oxidant and antioxidant profiles, respectively. Estrogen levels were significantly increased (p < 0.02) in premenopausal women (54.28 ± 9.34 pg/mL) as compared with postmenopausal women (18.10 ± 1.49 pg/mL). Postmenopausal women had lower levels of lipid hydroperoxide oxidation (p < 0.0001), lipid hydroperoxide levels evaluated by the area under the curve (AUC; 1,366,000 ± 179,400 AUC; p < 0.01), and hydroperoxides as measured by the ferrous oxidation-xylenol orange method (31.48 ± 2.7 μM; p < 0.0001). The MDA levels did not differ between pre- and postmenopausal women whether measured by thiobarbituric acid-reactive substances or high-performance liquid chromatography assays. No differences in AOPP and nitrite levels were observed between pre- and postmenopausal women. Postmenopausal women also exhibited a higher total radical antioxidant level (0.89 ± 0.08 μM Trolox; p < 0.0001). Postmenopausal women demonstrated lower levels of oxidative damage and a higher antioxidant capacity than premenopausal women.

Age at natural menopause in three central and eastern European urban populations: the HAPIEE study

OBJECTIVES

To investigate the age at menopause in three urban populations in Central and Eastern Europe and to assess whether the (suspected) differences can be explained by a range of socioeconomic, reproductive and behavioural factors.

METHODS

The Health, Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) Study examined random samples of populations aged 45-69 years in Novosibirsk (Russia), Krakow (Poland) and six Czech towns. Participants completed a questionnaire and attended an examination in clinic. A total of 12,676 of women were included in these analyses.

RESULTS

The median age at menopause was 50 years in Novosibirsk, 51 years in Czech towns and 52 years in Krakow; the Cox regression hazard ratios of menopause, compared with Krakow, were 1.47 (95% CI 1.40-1.55) for Novosibirsk and 1.10 (1.04-1.16) for Czech women. In multivariate analyses, higher education, using vitamin and mineral supplements and ever use of oral contraceptives were associated with later menopause, while smoking, abstaining from alcohol and low physical activity were associated with earlier menopause. These factors, however, did not explain the differences between populations; the multivariate hazard ratios of menopause, compared with Krakow, were 1.48 (1.40-1.57) for Novosibirsk and 1.11 (1.05-1.17) for Czech women.

CONCLUSIONS

In this large population based study, differences in age at menopause between Central and Eastern Europe populations were substantial and unexplained by a range of risk factors. Associations of age at menopause with risk factors were largely consistent with studies in other populations.