Relationship of relevant factors of atherosclerosis to menopause in Japanese women

A review of menopause nomenclature

Menopause nomenclature varies in the scholarly literature making synthesis and interpretation of research findings difficult. Therefore, the present study aimed to review and discuss critical developments in menopause nomenclature; determine the level of heterogeneity amongst menopause definitions and compare them with the Stages of Reproductive Aging Workshop criteria. Definitions/criteria used to characterise premenopausal and postmenopausal status were extracted from 210 studies and 128 of these studies were included in the final analyses. The main findings were that 39.84% of included studies were consistent with STRAW classification of premenopause, whereas 70.31% were consistent with STRAW classification of postmenopause. Surprisingly, major inconsistencies relating to premenopause definition were due to a total lack of reporting of any definitions/criteria for premenopause (39.84% of studies). In contrast, only 20.31% did not report definitions/criteria for postmenopause. The present findings indicate that there is a significant amount of heterogeneity associated with the definition of premenopause, compared with postmenopause. We propose three key suggestions/recommendations, which can be distilled from these findings. Firstly, premenopause should be transparently operationalised and reported. Secondly, as a minimum requirement, regular menstruation should be defined as the number of menstrual cycles in a period of at least 3 months. Finally, the utility of introducing normative age-ranges as supplementary criterion for defining stages of reproductive ageing should be considered. The use of consistent terminology in research will enhance our capacity to compare results from different studies and more effectively investigate issues related to women's health and ageing.

Fat mass changes during menopause: a metaanalysis

OBJECTIVE

Data: Fat mass has been shown to increase in aging women; however, the extent to which menopausal status mediates these changes remains unclear. The purpose of this review was to determine (1) how fat mass differs in quantity and distribution between premenopausal and postmenopausal women, (2) whether and how age and/or menopausal status moderates any observed differences, and (3) which type of fat mass measure is best suited to the detection of differences in fat mass between groups.

STUDY

This review with metaanalyses is reported according to Metaanalysis of Observational Studies in Epidemiology guidelines.

STUDY APPRAISAL AND SYNTHESIS METHODS

Studies (published up to May 2018) were identified via PubMed to provide fat mass measures in premenopausal and postmenopausal women. We included 201 cross-sectional studies in the metaanalysis, which provided a combined sample size of 1,049,919 individuals and consisted of 478,734 premenopausal women and 571,185 postmenopausal women. Eleven longitudinal studies were included in the metaanalyses, which provided a combined sample size of 2472 women who were premenopausal at baseline and postmenopausal at follow up.

RESULTS

The main findings of this review were that fat mass significantly increased between premenopausal and postmenopausal women across most measures, which included body mass index (1.14 kg/m²; 95% confidence interval, 0.95-1.32 kg/m²), bodyweight (1 kg; 95% confidence interval, 0.44-1.57 kg), body fat percentage (2.88%; 95% confidence interval, 2.13-3.63%), waist circumference (4.63 cm; 95% confidence interval, 3.90-5.35 cm), hip circumference (2.01 cm; 95% confidence interval, 1.36-2.65 cm), waist-hip ratio (0.04; 95% confidence interval, 0.03-0.05), visceral fat (26.90 cm²; 95% confidence interval, 13.12-40.68), and trunk fat percentage (5.49%; 95% confidence interval, 3.91-7.06 cm²). The exception was total leg fat percentage, which significantly decreased (-3.19%; 95% confidence interval, -5.98 to -0.41%). No interactive effects were observed between menopausal status and age across all fat mass measures.

CONCLUSION

The change in fat mass quantity between premenopausal and postmenopausal women was attributable predominantly to increasing age; menopause had no significant additional influence. However, the decrease in total leg fat percentage and increase in measures of central fat are indicative of a possible change in fat mass distribution after menopause. These changes are likely to, at least in part, be due to hormonal shifts that occur during midlife when women have a higher androgen (ie, testosterone) to estradiol ratio after menopause, which has been linked to enhanced central adiposity deposition. Evidently, these findings suggest attention should be paid to the accumulation of central fat after menopause, whereas increases in total fat mass should be monitored consistently across the lifespan.

Subclinical carotid atherosclerosis and hyperuricemia in relation to renal impairment in a rural Japanese population: the Nagasaki Islands study

OBJECTIVE

The influence of hyperuricemia on atherosclerosis is controversial. Subclinical carotid atherosclerosis can be defined in two ways in terms of mean and maximum carotid intima-media thickness (CIMT): one with mean CIMT≥1.1 mm and the other with maximum CIMT≥1.1 mm. However, no studies have been reported of the association between hyperuricemia and subclinical carotid atherosclerosis while taking the two different ways of classification into account.

METHODS

We conducted a cross-sectional study of 4133 subjects (1492 men and 2641 women) aged 30-89 years undergoing general health check-ups. For analysis of various associations, we calculated the multivariable odds ratios (ORs) for the two ways classifications of subclinical carotid atherosclerosis in relation to hyperuricemia.

RESULTS

Hyperuricemia-related renal impairment constitutes a significant marker for subclinical carotid atherosclerosis with mean CIMT≥1.1 mm for both men and women, while hyperuricemia per se was found to be beneficially associated with risk of subclinical carotid atherosclerosis with maximum CIMT≥1.1 mm for men. The classical cardiovascular risk factors without adjustment for glomerular filtration rate (GFR) of ORs for subclinical carotid atherosclerosis (mean CIMT≥1.1 mm) and subclinical carotid atherosclerosis (maximum CIMT≥1.1 mm) were 2.20(1.10-4.22) and 0.84(0.63-1.13) for men and 2.12(1.02-4.38) and 0.92(0.66-1.27) for women. After further adjustment for GFR, the corresponding values were 1.54(0.74-3.20) and 0.67(0.49-0.92) for men and 1.32(0.61-2.88) and 0.80(0.57-1.12) for women.

CONCLUSION

Hyperuricemia-related renal impairment is a significant marker for subclinical carotid atherosclerosis for both men and women, while hyperuricemia per se may be inversely associated with subclinical carotid atherosclerosis for men as seen in a rural community-dwelling Japanese population.

Blood pressure around the menopause: a population study

BACKGROUND

Hypertension is a major cardiovascular risk factor possibly explaining the excessive cardiovascular morbidity and mortality in postmenopausal women. Cross-sectional and longitudinal studies have explored this issue with diverging results. Our study sought to elucidate the impact of the menopause on blood pressure in a representative population sample.

METHODS

The study involved randomly selected 908 female residents of a Prague district, aged 45-54 years (respondence rate, 63.9%). Three definitions of the menopause were used: self-reported menstrual characteristics (premenopausal with the final menstrual period less than 60 days; late menopausal transition, with final menstrual period 60-365 days; and postmenopausal, final menstrual period more than 365 days before the examination), levels of follicle-stimulating hormone (< or = 40 IU/l for premenopausal and more than 40 IU/l for postmenopausal women), and both.

RESULTS

Age-adjusted and BMI-adjusted systolic blood pressure and diastolic blood pressure did not differ among the groups regardless of the definition of menopause. There was also no difference in the prevalence of hypertension and in the age-adjusted and BMI-adjusted odds ratio for hypertension. Multiple regression analysis testing the association between systolic blood pressure and diastolic blood pressure, and age, BMI, heart rate, smoking, and antihypertensive medication explained a rather small proportion of the BP variation. No correlation was found between BP and age in either subgroup; the closest correlation was always found between BP and BMI.

CONCLUSION

In our rather homogeneous representative population random sample of women around the menopause, the rise in blood pressure after the menopause appeared to be due to increased BMI rather than to ovarian failure per se.

Assessment of the body mass index and selected physiological parameters in pre- and post-menopausal women

The main purpose of this paper is to describe the variability of the body mass index (BMI) and selected physiological parameters (serum glucose, total serum cholesterol, systolic and diastolic blood pressure) in women before and after menopause. The empirical basis for the assessment is the material obtained in cross-sectional studies carried out in the years 1998-2001 in a group of 2204 women aged 35-65 years, residents of the Wielkopolska region, Poland. The results indicate that hormonal changes taking place in the climacterium bring about an increase in the BMI. It was observed that women receiving Hormone Replacement Therapy in the perimenopause had BMI significantly lower than naturally menopausal women. Increased levels of total serum cholesterol and blood glucose were recorded. The trend has a stronger relation with the age of the subjects than with the character of the menopause. The systolic and diastolic blood pressure values were also found to increase significantly after the menopause, but no relationship with the type of menopause was found.

Weight change in relation to natural menopause and other reproductive and behavioral factors in Japanese women

PURPOSE

To evaluate the effect of menopause on weight change in Japanese women.

METHODS

Community-based sample of 828 Japanese women who were premenopausal and aged 40 to 54 years completed a self-administered questionnaire asking information on demographic factors, body size, reproductive history and dietary and behavioral factors in 1992. They responded to a follow-up questionnaire asking weight and menopausal status in 1998.

RESULTS

Women gained weight modestly, on average, 0.17 kg during the 6-year study period. Weight gain was significantly higher in women who remained premenopausal at follow-up than those who had natural menopause during the study period. Weight gain was significantly associated with early menarche in women who had natural menopause and with high parity in women remained premenopausal.

CONCLUSION

Reproductive factors rather than sociodemographic and behavioral factors appeared to be associated with weight change during the perimenopausal period. Onset of menopause may diminish weight gain. In contrast, early menarche and high parity showed relationships with weight gain.

Dietary intake of phytoestrogens is associated with a favorable metabolic cardiovascular risk profile in postmenopausal U.S.women: the Framingham study

Hypertension, central obesity and dyslipidemia are associated with high cardiovascular risk. Estrogen therapy in women has beneficial effects on some of these metabolic cardiovascular risk factors. It is not known whether dietary estrogens have similar effects, especially in Western populations. We studied the association between dietary phytoestrogen intake and metabolic cardiovascular risk factors in postmenopausal women. For this purpose, 939 postmenopausal women participating in the Framingham Offspring Study were included in this cross-sectional study. Mean blood pressure, waist-hip ratio (WHR) and lipoprotein levels were determined in quartile categories of dietary phytoestrogen (isoflavones and lignans) intake, determined by a food-frequency questionnaire. In addition, a metabolic syndrome score was defined according to WHO criteria (range 0-6). The WHR was lower in women in the highest quartile of intake of lignans compared with the lowest [-0.017; 95% confidence interval (CI) -0.030 to -0.0016]. In the highest quartile of intake of isoflavones, plasma triglyceride levels were 0.16 mmol/L lower (95% CI, -0.30 to -0.02) compared with the lowest quartile of isoflavones; for lignan intake, this difference was 0.23 mmol/L (95% CI, -0.37 to -0.09). In the highest quartile of isoflavone intake, the mean cardiovascular risk factor metabolic score was 0.43 points lower (95% CI, -0.70 to -0.16) than the lowest quartile. The difference in this score between the extreme quartiles of intake of lignans was -0.55 points (95% CI, -0.82 to -0.28). In conclusion, high intake of phytoestrogens in postmenopausal women appears to be associated with a favorable metabolic cardiovascular risk profile.

Effects of menopause on trends of serum cholesterol, blood pressure, and body mass index

BACKGROUND

To elucidate the impact of menopause on coronary risk factors, we determined the trends of serum cholesterol (mg/dL), blood pressure (BP, mm Hg), and body mass index (BMI, kg/m2) and investigated whether menopause affects these trends in women in Nagasaki, Japan.

METHODS AND RESULTS

Trends of cholesterol, systolic BP (SBP), and BMI from 9 years before menopause through 9 years after menopause in 579 women with natural menopause (ranging in age from 40.2+/-3.1 to 57.9+/-3.1 years; age at menopause, 49.4+/-3.0 years) and 134 women with surgical menopause (hysterectomy with or without bilateral oophorectomy; ranging in age from 34.9+/-4.5 to 51.7+/-5.1 years; age at menopause, 42.9+/-5.0 years) and those in 579 and 134 age- and time-matched male subjects (ranging in age from 40.1+/-3.1 to 57.8+/-3.2 years and from 35.2+/-4.5 to 51.6+/-5.0 years, respectively) in Nagasaki were determined by rearrangement of the data from 1958 to 1989 with time of menopause as the datum line. Although cholesterol tended to increase with age in both sexes, it increased significantly in women from 3 years before natural menopause to 1 year after natural menopause and from 1 year before surgical menopause to 1 year after surgical menopause. SBP and BMI did not exhibit a significant increase in relation to natural or surgical menopause. In male subjects, no significant increase of cholesterol, SBP, or BMI was observed at the age corresponding to natural or surgical menopause.

CONCLUSIONS

Natural menopause and surgical menopause exert an effect only on cholesterol, and an increase in cholesterol precedes natural menopause by 3 years and occurs at the time of surgical menopause.

Natural menopause and cardiovascular disease risk factors. The Poland and US Collaborative Study on Cardiovascular Disease Epidemiology

Changes in risk factor levels associated with menopause have been reported in many studies in the United States and western Europe, where estrogen replacement therapy and surgical menopause are common. We studied risk factor associations in Polish women, for whom estrogen replacement therapy and surgical menopause are uncommon. The 357 postmenopausal women had higher total cholesterol levels (0.43 mmol/L) and low-density-lipoprotein cholesterol levels (0.36 mmol/L than did the 372 premenopausal women of similar ages. Triglycerides, high-density-lipoprotein cholesterol, body mass index, and blood pressure did not differ by menopausal status. We conclude that natural menopause is associated with higher levels of total and low-density-lipoprotein cholesterol levels. Natural menopause is not associated with large changes in other risk factors in this sample.

Serum total and HDL cholesterols according to reproductive status in Japanese females

In order to observe variations according to reproductive status, serum total cholesterol (TC) and HDL cholesterol (HDL-C) were investigated in 153 pregnant, in 153 age-adjusted non-pregnant females, in 787 females aged 45-54 years living in a northern suburb of Tokyo, and in 150 12-year-old girls from a private junior high school in a southern suburb of Tokyo. Non-menstruating (non-menarcheal, postmenopausal) females had significantly higher TC and significantly lower HDL-C/TC than menstruating (menarcheal, premenopausal) females did in both the age groups of 12 and 45-54 years, although no significant difference of HDL-C was found between them. The menstruating females tended to be more overweight in Quetelet's index and had thicker skinfolds. Pregnant females at the eighth month of gestation revealed a significantly high value of both TC and HDL-C vs age-adjusted non-pregnant females, while at the fourth month of gestation only HDL-C was high.

Effect of natural oestrogen/gestagen therapy on uric acid metabolism in post-menopausal women

Uric acid metabolism was studied in groups of early post-menopausal women before and during long-term administration of natural oestrogen/gestagen (n = 21), bendroflumethiazide (n = 19) or placebo (n = 34). Serum uric acid rose definitely, by 13.0% during thiazide, and decreased slightly, by 4.9%, during hormone treatment. The latter deviation did not differ significantly from that of -2.9% seen in the placebo group. The urinary excretion rates of uric acid observed during thiazide and hormone treatment did not differ significantly from that of the placebo group. It is concluded, that within the present design of study, which readily permits detection of the well-known hyperuricaemic action of thiazide, oestrogen/gestagen hardly affects uric acid metabolism.

Iron and the sex difference in heart disease risk

Premenopausal women in affluent societies are protected from heart diseases which kill large numbers of men. The basis for this sex difference and the loss of protection with menopause is unknown. The hypothesis offered is that the greater incidence of heart diseases in men and postmenopausal women compared with the incidence in premenopausal women is due to higher levels of stored iron in these two groups. The hypothesis is supported by observations of (1) myocardial failure in iron strong disease, (2) accumulation of stored iron with age in men, and (3) accumulation of stored iron after menopause to levels found in men. In addition, the heart diseases of affluence are rare among impoverished peoples who are often iron deficient. The depletion of iron stores by regular phlebotomy could be the experimental system for testing this hypothesis, and a preventive therapy if the hypothesis is confirmed.