A randomized, placebo-controlled trial on the effects of soy protein containing isoflavones on quality of life in postmenopausal women

Investigating the Role of 17β-Estradiol on the Serotonergic System, Targeting Soy Isoflavones as a Strategy to Reduce Menopausal Depression: A Mechanistic Review

Low serotonin is one factor implicated in the development of depression. 17β-estradiol (E2) has been shown to modulate gene expression regulating the neurotransmission of serotonin. Sex hormone levels fluctuate dramatically during the menopausal transition, coinciding with a 14-fold increased risk of depression. This review aimed to examine the effect of soy isoflavones to support decreased and variable E2 levels before and after menopause, linked to an investigation of the pathophysiological mechanisms underlying the protective influence of E2 on the serotonin pathway. The overall aim of this review is to assess the potential of soy isoflavones to reduce depression in middle-aged women. A systematic literature search was performed in three stages. 1,421 papers were screened for relevance to the research aims and objectives. 63 papers were selected based on pre-defined inclusion/exclusion criteria (13 reviews, 24 mechanistic and 26 intervention studies) and critically appraised. Available research supported the hypotheses that E2 increases serotonin synthesis and availability through stimulation of tryptophan hydroxylase-2 (TPH-2) and decreased degradation by monoamine oxidase-A (MAO-A). There was less scientific agreement on the effects of E2 on serotonin transporter (SERT) and serotonin receptors 1 A and 2 A. Studies varied widely on the effectiveness of soy isoflavones in reducing depressive symptoms in (peri)menopausal women. Animal and human studies acknowledge women's increased risk of depression linked to fluctuating E2 rather than absolute levels. However, mechanisms linking E2 variability with depression remain an underrepresented area of research. Study limitations and heterogeneity may contribute to varying results for soy isoflavones and some effects of E2 on the serotonin pathway.

Polyphenols as novel interventions for depression: exploring the efficacy, mechanisms of action, and implications for future research

Numerous animal and human studies have assessed the relationship between polyphenols and outcomes related to depression. However, no comprehensive synthesis of the main findings has been conducted. The aim of this manuscript was to systematically review the available evidence from animal and human studies on the association and the effects of dietary polyphenols on depression and provide recommendations for future research. We based our review on 163 preclinical animal, 16 observational and 44 intervention articles assessing the relationship between polyphenols and outcomes related to depression. Most animal studies demonstrated that exposure to polyphenols alleviated behaviours reported to be associated with depression. However, human studies are less clear, with some studies reporting and inverse relationship between the intake of some polyphenols, and polyphenol rich foods and depression risk and symptoms, while others reporting no association or effect. Hence, while there has been extensive research conducted in animals and there is some supporting evidence in humans, further human studies are required, particularly in younger and clinical populations.

Effects of nutritional interventions on the severity of depressive and anxiety symptoms of women in the menopausal transition and menopause: a systematic review, meta-analysis, and meta-regression

IMPORTANCE

Depression and anxiety may significantly affect women during the menopausal transition. In addition to traditional treatment strategies such as hormone therapy, antidepressants, and psychotherapy, nutritional interventions have been increasingly studied, but there is no consensus about their role in this patient population.

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the effect of nutritional interventions on the severity of depressive (DS) and anxiety (AS) symptoms in women during the menopausal transition or menopausal years.

EVIDENCE REVIEW

Electronic search using databases PubMed, Cochrane, and Embase to identify articles indexed until January 31, 2021, focusing on randomized placebo-controlled trials documenting the effect of diet, food supplements, and nutraceuticals on DS and AS.

FINDINGS

Thirty-two studies were included (DS, n = 15; AS, n = 1; DS and AS combined, n = 16). We found two studies that demonstrated data combined with other interventions: one with lifestyle interventions (vitamin D plus lifestyle-based weight-loss program) and another with exercise (omega 3 plus exercise). The pooled effect size favored the intervention group over placebo for both DS and AS (DS: standardized mean difference, -0.35 [95% confidence interval, -0.68 to -0.03; P = 0.0351]; AS: standardized mean difference, -0.74 [95% CI, -1.37 to -0.11; P = 0.0229]). There was significant heterogeneity in the pooled results, which can be attributed to differences in assessment tools for depression and anxiety as well as the variety of nutritional interventions studied. The subgroup analysis showed a statistically significant effect of menopausal status (perimenopausal or menopausal) but not the type or duration of nutritional intervention. Older age was the only significant predictor of the effect size of nutritional interventions in the meta-regression.

CONCLUSIONS AND RELEVANCE

Nutritional interventions are promising tools for the management of mood/anxiety symptoms in women during the menopausal transition and in postmenopausal years. Because of significant heterogeneity and risk of bias among studies, the actual effect of different approaches is still unclear.

Exploring the Impact of Flavonoids on Symptoms of Depression: A Systematic Review and Meta-Analysis

Recent evidence suggests that diet modifies key biological factors associated with the development of depression. It has been suggested that this could be due to the high flavonoid content commonly found in many plant foods, beverages and dietary supplements. Our aim was to conduct a systematic review to evaluate the effects of dietary flavonoids on the symptoms of depression. A total of 46 studies met the eligibility criteria. Of these, 36 were intervention trials and 10 were observational studies. A meta-analysis of 36 clinical trials involving a total of 2788 participants was performed. The results showed a statistically significant effect of flavonoids on depressive symptoms (mean difference = −1.65; 95% C.I., −2.54, −0.77; p < 0.01). Five of the 10 observational studies included in the systematic review reported significant results, suggesting that a higher flavonoid intake may improve symptoms of depression. Further studies are urgently required to elucidate whether causal and mechanistic links exist, along with substantiation of functional brain changes associated with flavonoid consumption.

Effects of Phytoestrogen Supplement on Quality of Life of Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

The effect of phytoestrogen on postmenopausal quality of life is unclear. This study evaluated the effects of phytoestrogen supplement on quality of life for postmenopausal women.

Methods

We conducted a systematic review and meta-analysis of randomized controlled trials on the effects of phytoestrogen supplements on the quality of life of postmenopausal women. We searched PubMed, MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials on March 31, 2018, for relevant randomized controlled trials. Two authors independently selected studies, assessed risk of bias, and extracted data. Disagreement was resolved through discussion with a third author.

Results

We involved 10 articles in the systematic review. 8 studies and a total of 1,129 subjects were included in the meta-analysis. The questionnaires used in the evaluation of quality of life were as follows: SF-36, 4 studies; MENQOL, 4 studies; For Short Form 36 surveys, phytoestrogen groups scored significantly higher for body pain (mean difference = 3.85, 95% confidence interval [CI] = [1.14, 6.57], P < 0.01), mental health (mean difference = 4.01, 95% CI = [1.49, 6.57], P < 0.01), and role limitations caused by emotional problems domains (mean difference = 3.83, 95% CI = [1.81, 5.85], P < 0.01). No statistically significant difference was obtained from Menopause-Specific Quality of Life surveys (vasomotor domain mean difference 0.14, 95% CI = [−0.08, 0.36], P = 0.20; physical domain mean difference 0.20, 95% CI [−0.08, 0.48], P = 0.15; psychological domain mean difference −0.10, 95% CI [−0.26, 0.07], P = 0.27; sexual domain mean difference −0.17, 95% CI [−0.42, 0.09], P = 0.19).

Conclusion

Current evidence does not support phytoestrogen supplementation improving postmenopausal quality of life. Further comprehensive trials or long-term follow-up studies are warranted.

Comprehensive evaluation of the role of soy and isoflavone supplementation in humans and animals over the past two decades

Soy and soy-based foods are considered healthy, particularly in many Asia-Pacific countries, where soy products have long been consumed. Soy and soy-related products have been found to help prevent the occurrence of cardiovascular diseases and certain types of cancer, such as breast and prostate cancer. These products can also have antioxidative effects that alleviate hot flashes during menopause and bone loss. These biological and therapeutic functions are primarily due to the isoflavones derived from soy, whose structure is similar to the structure of 17-β-oestradiol. Despite the many health benefits for humans and animals, the application of isoflavones remains controversial because of their anti-oestrogenic properties. We focused on general information regarding isoflavones, as well as their structure, function, and application. We summarized evidence showing that dietary or supplemental isoflavones exert protective effects on the health of humans and animals. Based on the literature, we conclude that soy foods and isoflavones may be effective and safe; however, more high-quality trials are needed to fully substantiate their potential use.

Effect of Foeniculum vulgare (fennel) on symptoms of depression and anxiety in postmenopausal women: a double-blind randomised controlled trial

The aim of this study was to evaluate the effect of Foeniculum vulgare (fennel) on anxiety and depression symptoms in postmenopausal women. This study was a double-blind, randomised, placebo-controlled trial, in which 60 eligible postmenopausal women were selected and then randomly assigned to fennel and placebo groups. Then, symptoms of anxiety and depression were measured using Hospital Anxiety and Depression Scale (HADS) and Zung's Self Rating Depression Scale (SDS). Following the intervention, the score of HADS (depression and anxiety subgroups) and SDS did not show any significant decrease in the sample under study. However, the analysis of patients with depression or anxiety disorder showed a borderline or significant improvement. Further studies with a larger sample size are required to confirm the findings. Impact statement Current knowledge on the subject: Based on the results of in vivo and in vitro animal studies, fennel may have anti-depressant and anti-anxiety properties. The contribution made by this study: It appears that fennel is effective in menopausal women with depression and anxiety disorders. The implications of findings for clinical practice and future research: Further studies with a larger sample size are required to confirm the actual effect of fennel in clinical setting.

Evaluation of the potential antidepressant effects of soybean isoflavones

OBJECTIVE

The aim of the study was to determine whether isoflavones affect depressive symptoms in women.

METHODS

Literature searches were conducted to identify clinical and epidemiologic studies that evaluated the impact of soy intake and isoflavone exposure on depressive symptoms. References from identified studies were also evaluated to identify eligible studies.

RESULTS

Only limited epidemiologic research has evaluated the impact of soy or isoflavone intake on depression although several studies from China and Japan did find soy product intake was inversely related to risk of depression. Often times, soy was, however, evaluated only as a component of a summative dietary pattern (eg, a "Japanese" or "Healthy" diet). Of the 20 intervention studies identified, roughly half found statistically significant reductions in depressive symptoms in response to isoflavones although several had design weakness. Of those studies reporting a lack of antidepressant effects of isoflavones, design limitations likely contributed to the lack of efficacy. In all but two trials, assessment of depression was, however, a secondary outcome. It is notable that both trials in which depression was a primary outcome found isoflavones significantly improved symptoms.

CONCLUSIONS

Although the data are inconsistent and limited, the clinical and epidemiologic evidence suggests that isoflavones may offer a safe, well-tolerated option for management of depression. Furthermore, the intervention doses used in the clinical studies fall well within the dietary range. The extant literature reveals key design features for future studies, which based upon the results of this review, are clearly warranted.

Exercise for vasomotor menopausal symptoms

BACKGROUND

Evidence suggests that many perimenopausal and early postmenopausal women will experience menopausal symptoms; hot flushes are the most common. Symptoms caused by fluctuating levels of oestrogen may be alleviated by hormone therapy (HT), but a marked global decline in its use has resulted from concerns about the risks and benefits of HT. Consequently, many women are seeking alternatives. As large numbers of women are choosing not to take HT, it is increasingly important to identify evidence-based lifestyle modifications that have the potential to reduce vasomotor menopausal symptoms.

OBJECTIVES

To examine the effectiveness of any type of exercise intervention in the management of vasomotor symptoms in symptomatic perimenopausal and postmenopausal women.

SEARCH METHODS

Searches of the following electronic bibliographic databases were performed to identify randomised controlled trials (RCTs): Cochrane Menstrual Disorders and Subfertility Group Specialised Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (Wiley Internet interface), MEDLINE (Ovid), EMBASE (Ovid), PsycINFO (Ovid), the Science Citation Index and the Social Science Citation Index (Web of Science), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (Ovid) and SPORTDiscus. Searches include findings up to 3 March 2014.

SELECTION CRITERIA

RCTs in which any type of exercise intervention was compared with no treatment/control or other treatments in the management of menopausal vasomotor symptoms in symptomatic perimenopausal/postmenopausal women.

DATA COLLECTION AND ANALYSIS

Five studies were deemed eligible for inclusion. Two review authors independently selected the studies, and three review authors independently extracted the data. The primary review outcome was vasomotor symptoms, defined as hot flushes and/or night sweats. We combined data to calculate standardised mean differences (SMDs) with 95% confidence intervals (CIs). Statistical heterogeneity was assessed using the I(2) statistic. We assessed the overall quality of the evidence for main comparisons using GRADE (Grades of Recommendation, Assessment, Development and Evaluation) methods.

MAIN RESULTS

We included five RCTs (733 women) comparing exercise with no active treatment, exercise with yoga and exercise with HT. The evidence was of low quality: Limitations in study design were noted, along with inconsistency and imprecision. In the comparison of exercise versus no active treatment (three studies, n = 454 women), no evidence was found of a difference between groups in frequency or intensity of vasomotor symptoms (SMD -0.10, 95% CI -0.33 to 0.13, three RCTs, 454 women, I(2) = 30%, low-quality evidence). Nor was any evidence found of a difference between groups in the frequency or intensity of vasomotor symptoms when exercise was compared with yoga (SMD -0.03, 95% CI -0.45 to 0.38, two studies, n = 279 women, I(2) = 61%, low-quality evidence). It was not possible to include one of the trials in the meta-analyses; this trial compared three groups: exercise plus soy milk, soy milk only and control; results favoured exercise relative to the comparators, but study numbers were small. One trial compared exercise with HT, and the HT group reported significantly fewer flushes in 24 hours than the exercise group (mean difference 5.8, 95% CI 3.17 to 8.43, 14 participants). None of the trials found evidence of a difference between groups with respect to adverse effects, but data were very scanty.

AUTHORS' CONCLUSIONS

Evidence was insufficient to show whether exercise is an effective treatment for vasomotor menopausal symptoms. One small study suggested that HT is more effective than exercise. Evidence was insufficient to show the relative effectiveness of exercise when compared with HT or yoga.

Effect of soy isoflavone supplementation on menopausal quality of life

OBJECTIVE

The purpose of this study was to assess the effect of soy isoflavone supplementation on quality of life in postmenopausal women.

METHODS

A multicenter, randomized, double-blind, placebo-controlled 24-month trial was conducted to assess the effect of 80 or 120 mg of daily aglycone hypocotyl soy isoflavone supplementation on quality of life in 403 postmenopausal women using a validated Menopause-Specific Quality of Life questionnaire.

RESULTS

Menopause-Specific Quality of Life domain scores at 1 year and 2 years were similar to baseline. There were no differences in domain scores among treatment groups.

CONCLUSIONS

Soy isoflavone supplementation offers no benefit to quality of life in postmenopausal women.

Genistein effects on quality of life and depression symptoms in osteopenic postmenopausal women: a 2-year randomized, double-blind, controlled study

SUMMARY

Postmenopausal estrogen decline is implicated in several age-related physical and psychological changes in women, including decreases in perceived quality of life. The phytoestrogen genistein at a dose of 54 mg daily in osteopenic postmenopausal women after 2 years implies an improvement on quality of life and depression symptoms.

INTRODUCTION

Postmenopausal estrogen decline is implicated in several age-related physical and psychological changes in women, including decreases in perceived quality of life (QoL). A number of trials with hormone therapy showed beneficial effects of the intervention on quality of life parameters. However, because of known or suspected serious side effects of conventional hormone therapy, there is a need for alternatives.

METHODS

We conducted a double-blind randomized placebo-controlled trial using the isoflavone genistein, 54 mg, or placebo for 2 years. In this trial, we recruited 262 postmenopausal women aged 49 to 67 years.

RESULTS

At baseline, after 1 year, and at final visit, participants filled in the Short Form of 36 questions (SF-36) and the Zung Self-rating Depression Scale (ZSDS). For the placebo group, scores on all dimensions of the SF-36 decreased after 1 and 2 years. The genistein group showed increases on all dimensions of the SF-36 at the end of the study. There were, however, statistically significant differences in changes of scores between the two intervention groups. For the ZSDS, similarly, significant differences were found between groups.

CONCLUSION

In conclusion, the findings of this randomized trial showed that genistein improves quality of life (health status, life satisfaction, and depression) in osteopenic postmenopausal women.

Phytoestrogens for menopausal vasomotor symptoms

BACKGROUND

Vasomotor symptoms, such as hot flushes and night sweats, are very common during the menopausal transition. Hormone therapy has traditionally been used as a highly effective treatment, but concerns about increased risk of some chronic diseases have markedly increased the interest of women in alternative treatments. Some of the most popular of these treatments are foods or supplements enriched with phytoestrogens-plant-derived chemicals that have estrogenic action.

OBJECTIVES

To assess the efficacy, safety and acceptability of food products, extracts and dietary supplements containing high levels of phytoestrogens when compared with no treatment, placebo or hormone therapy for the amelioration of vasomotor menopausal symptoms (such as hot flushes and night sweats) in perimenopausal and postmenopausal women.

SEARCH METHODS

Searches targeted the following electronic databases: the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of randomised trials (29 July 2013), the Cochrane Register of Controlled Trials (CENTRAL; 29 July 2013), MEDLINE (inception to 29 July 2013), EMBASE (inception to 29 July 2013), AMED (1985 to 29 July 2013), PsycINFO (inception to 29 July 2013) and CINAHL (inception to 29 July 2013). Attempts were made to access grey literature by sending letters to pharmaceutical companies and performing searches of ongoing trial registers. Reference lists of included trials were also searched.

SELECTION CRITERIA

Studies were included if they were randomised, included perimenopausal or postmenopausal participants with vasomotor symptoms (hot flushes or night sweats), lasted at least 12 weeks and provided interventions such as foods or supplements with high levels of phytoestrogens (not combined with other herbal treatments). Trials that included women who had breast cancer or a history of breast cancer were excluded.

DATA COLLECTION AND ANALYSIS

Selection of trials, extraction of data and assessment of quality were undertaken by at least two review authors. Most trials were too dissimilar for their results to be combined in a meta-analysis, so these findings are provided in narrative 'Summary of results' tables. Studies were grouped into broad categories: dietary soy, soy extracts, red clover extracts, genistein extracts and other types of phytoestrogens. Five trials used Promensil, a red clover extract; results of these trials were combined in a meta-analysis, and summary effect measures were calculated.

MAIN RESULTS

A total of 43 randomised controlled trials (4,364 participants) were included in this review. Very few trials provided data suitable for inclusion in a meta-analysis. Among the five trials that yielded data assessing the daily frequency of hot flushes suitable for pooling, no significant difference overall was noted in the incidence of hot flushes between participants taking Promensil (a red clover extract) and those given placebo (mean difference (MD) -0.93, 95% confidence interval (CI) -1.95 to 0.10, I(2) = 31%). No evidence indicated a difference in percentage reduction in hot flushes in two trials between Promensil and placebo (MD 20.15, 95% CI -12.08 to 52.38, I(2) = 82%). Four trials that were not combined in meta-analyses suggested that extracts with high (> 30 mg/d) levels of genistein consistently reduced the frequency of hot flushes. Individual results from the remaining trials were compared in broad subgroups such as dietary soy, soy extracts and other types of phytoestrogens that could not be combined. Some of these trials found that phytoestrogen treatments alleviated the frequency and severity of hot flushes and night sweats when compared with placebo, but many trials were small and were determined to be at high risk of bias. A strong placebo effect was noted in most trials, with a reduction in frequency ranging from 1% to 59% with placebo. No indication suggested that discrepant results were due to the amount of isoflavone in the active treatment arm, the severity of vasomotor symptoms or trial quality factors. Also, no evidence indicated that these treatments caused oestrogenic stimulation of the endometrium or the vagina or other adverse effects when used for up to two years.

AUTHORS' CONCLUSIONS

No conclusive evidence shows that phytoestrogen supplements effectively reduce the frequency or severity of hot flushes and night sweats in perimenopausal or postmenopausal women, although benefits derived from concentrates of genistein should be further investigated.

Effect of exercise combined with phytoestrogens on quality of life in postmenopausal women

BACKGROUND

Postmenopausal women seem to favor alternative therapies such as exercise and phytoestrogens as a substitute for potentially harmful hormone replacement therapy. Based on previous research, we hypothesized that phytoestrogens combined with exercise could have a synergic effect on women's health.

OBJECTIVE

To verify whether phytoestrogens enhance the response to mixed training regarding menopausal symptoms and quality of life in postmenopausal women.

METHODS

From a pool of women participating in a 6-month randomized, controlled exercise study, 21 received a placebo (mean age 58.3 ± 5.4 years, body mass index 29.8 ± 5.1 kg/m(2)) and 19 received phytoestrogen supplements (mean age 60.1 ± 3.4 years; body mass index 30.3 ± 4.6 kg/m(2)). Body weight, fat mass and lean body mass (dual-energy X-ray absorptiometry) were assessed. Quality of life was estimated by the Short Form-36 (SF-36) and Perceived Stress Scale-10 (PSS-10) questionnaires, and menopausal symptoms by the Kupperman index. All measurements were performed before and after the intervention.

RESULTS

Although the Kupperman index and PSS-10 remained unchanged in both groups, the SF-36 Physical Component Summary and almost all the SF-36 subscales (except for role-emotional and mental health) increased only in the exercise group taking phytoestrogens (0.001 < p < 0.04).

CONCLUSION

While phytoestrogens combined with mixed exercise were not sufficient to improve menopausal symptoms, it seemed to be a better strategy than exercise alone to improve the general quality of life in postmenopausal women.

Effects of isoflavones on breast density in pre- and post-menopausal women: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Isoflavones from soy and red clover exert modest hormonal effects in women, but the relevance to risk of breast cancer is unclear. The aim of this meta-analysis was to assess the effects of isoflavone-rich foods or supplements on a biomarker of breast cancer risk, women's mammographic density.

METHODS

Electronic searches were performed on The Cochrane Library, Medline and EMBASE (to June 2009), and reference lists and trial investigators were consulted to identify further studies. Randomized controlled trials (RCTs) of isoflavone-rich foods or supplements versus placebo with a duration of at least 6 months were included in our analysis. Inclusion/exclusion, data extraction and validity assessment were carried out independently in duplicate, and meta-analysis used to pool study results. Subgrouping, sensitivity analysis, assessment of heterogeneity and funnel plots were used to interpret the results.

RESULTS

Eight RCTs (1287 women) compared isoflavones with placebo for between 6 months and 3 years. Meta-analysis suggested no overall effect of dietary isoflavones on breast density in all women combined [mean difference (MD) 0.69%, 95% confidence interval (CI) -0.78 to 2.17] or post-menopausal women (MD -1.10%, 95% CI -3.22 to 1.03). However, there was a modest increase in mammographic density in premenopausal women (MD 1.83%, 95% CI 0.25-3.40) without heterogeneity but this effect was lost in one of three sensitivity analyses.

CONCLUSIONS

Isoflavone intake does not alter breast density in post-menopausal women, but may cause a small increase in breast density in premenopausal women. Larger, long-term trials are required to determine if these small effects are clinically relevant.

Quality of life and climacteric complaints amongst women seeking medical advice in Taiwan: assessment using the WHOQOL-BREF questionnaire

OBJECTIVE

To determine the impact of the climacteric transition on health-related quality of life amongst women, between the ages of 45 and 55 years, seeking medical advice in Taiwan.

METHOD

A total of 203 women seeking medical advice (SMA) were drawn from a special integrated clinic, with a further 349 healthy referents of the same age, range and gender, with no history of hormone replacement therapy and living in the same municipality, also being recruited from a national health survey sample for comparison. Each one was asked to fill out the brief questionnaire of the Taiwan version of the World Health Organization Quality of Life (WHOQOL-BREF), assessing quality of life on 26 items in four domains (physical, psychological, social and environmental). SMA subjects were also questioned about the 21 most frequent symptoms. Multiple regression analyses were conducted to control variables such as age, marital status, religion and educational attainment.

RESULTS

The mean scores for the physical, psychological and social domains were significantly lower than those of the healthy referents, as was the overall quality of life for SMA women. Although usual vasomotor symptoms did not significantly predict quality of life in the SMA subjects, after controlling for demographic factors, insomnia and emotional disturbance were found to be major determinants of the scores in the different domains.

CONCLUSION

Insomnia and emotional disturbance should be taken into consideration in the management of climacteric women seeking medical advice.

Efficacy of soy isoflavones for depressive symptoms of the climacteric syndrome

OBJECTIVES

To evaluate the efficacy of soy isoflavones extract (SIE) in the treatment of depressive symptoms in women with climacteric syndrome.

METHODS

Placebo-controlled double-blind randomized study with 84 climacteric outpatients attended in the Lauro Wanderley University Hospital in Joao Pessoa (PB), Brazil. In the assessment of the depressive symptoms, the Brazilian version of the Center of Epidemiologic Studies of Depression (CES-D) scale was used, on the pre-treatment visits (VT1), 8th (VT2) and 16th (VT3) weeks after treatment. The experimental group (EG) received the daily dose of 120mg SIE and the control group (CG), placebo. The primary efficacy measure was the comparison of the percent reductions in the CES-D scores from VT1 to VT3 between EG and CG (t-test, p<0.05). The security analysis consisted of laboratory and clinical evaluation of adverse events.

RESULTS

The CES-D scores in the EG reduced from 12.5 (+/-4.2) in VT1 to 9.9 (+/-3.6) in VT2 (VT20.05). In the outcome of the 16-week treatment (VT1-VT3), reduction of the CES-D scores did not reach statistical significance between groups. There were no clinically relevant adverse events attributable to the treatment.

CONCLUSIONS

The treatment with soy isoflavones did not produce significant reduction on the depressive symptoms of a predominantly affective nature evaluated in this study. The symptomatic reduction initially observed was apparently a nonspecific response to treatment, corroborating evidences from the literature on the placebo phenomenon in treatment of the climacteric syndrome.

Soy protein containing isoflavones and mammographic density in a randomized controlled trial in postmenopausal women

BACKGROUND

The relatively high dietary intake of soy in Asian countries has been hypothesized to, at least partly, explain the lower breast cancer incidence patterns in these countries compared with the Western world. The aim of the present study was to determine the effect of daily soy supplementation on mammographic density, one of the strongest known risk factors for breast cancer.

METHODS

A double-blind, randomized, controlled trial was conducted to compare the effects of soy protein intake containing 99 mg isoflavones daily with intake of milk protein (placebo) for the duration of 1 year. Two hundred and two Dutch postmenopausal women ages 60 to 75 years were randomized. Mammographic density was assessed using a quantitative computer-assisted method on digitized mammograms. Equol producer status was assessed in plasma provided at the final visit (soy group) or after a 3-day challenge with soy after the trial was finished (placebo group).

RESULTS

A total of 175 women completed the baseline visits and at least one follow-up visit and were included in the intention-to-treat analyses. For 126 women, both pre- and post-trial mammograms were available. Mammographic density decreased in both study arms, but the decrease did not differ significantly between intervention and placebo groups. Equol producer status did not modify the results.

CONCLUSION

The results of this trial do not support the hypothesis that a diet high in soy protein among postmenopausal women decreases mammographic density.

Phytoestrogens for vasomotor menopausal symptoms

BACKGROUND

Vasomotor symptoms, such as hot flushes and night sweats, are very common during the menopausal transition. Hormone replacement therapy has traditionally been used as a very effective treatment but concerns over increased risks of some chronic diseases have markedly increased the interest of women in alternatives. Some of the most popular of these are treatments based on foods or supplements enriched with phytoestrogens, plant-derived chemicals that have oestrogenic action.

OBJECTIVES

To assess the efficacy, safety and acceptability of foods and supplements based on high levels of phytoestrogens for reducing hot flushes and night sweats in postmenopausal women.

SEARCH STRATEGY

Searches were undertaken of the following electronic databases: the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of randomised trials, Cochrane Register of Controlled Trials (CENTRAL) (March 2007), MEDLINE (1966 to March 2007), EMBASE (1980 to March 2007), AMED (1985 to March 2007), PsycINFO (1986 to March 2007) and CINAHL (1982 to March 2007). Attempts were made to access grey literature by letters to pharmaceutical companies and searches of ongoing trial registers. Reference lists of included trials were also searched.

SELECTION CRITERIA

Studies were included if they were randomised, had peri- or postmenopausal participants with vasomotor symptoms, a duration of at least 12 weeks and where the intervention was a food or supplement with high levels of phytoestrogens (and not combined with other herbal treatments). Trials of women who had breast cancer or a history of breast cancer were excluded.

DATA COLLECTION AND ANALYSIS

Selection of trials, data extraction and quality assessment were undertaken by at least two authors. Most of the trials were too dissimilar to combine in meta-analysis and their results are provided in table format. Studies were grouped into broad categories: dietary soy, soy extracts, red clover extracts and other types of phytoestrogen. Five trials used Promensil, a red clover extract; these trials were combined in a meta-analysis and summary effect measures were calculated.

MAIN RESULTS

Thirty trials comparing phytoestrogens with control met the inclusion criteria. Very few trials had data suitable for combining in meta-analysis. Of the five trials with data suitable for pooling that assessed daily frequency of hot flushes, there was no significant difference overall in the frequency of hot flushes between Promensil (a red clover extract) and placebo (WMD=-0.6, 95% CI -1.8 to 0.6). There was no evidence of a difference in percentage reduction in hot flushes in two trials between Promensil and placebo (WMD=20.2, 95% CI -12.1 to 52.4). Individual results from the remaining trials were compared. Some of the trials found that phytoestrogen treatments alleviated the frequency and severity of hot flushes and night sweats when compared to placebo but many of the trials were of low quality and were underpowered. There was a strong placebo effect in most trials with a reduction in frequency ranging from 1% to 59% with placebo. There was no indication that the discrepant results were due to the amount of isoflavone in the active treatment arm, the severity of vasomotor symptoms or trial quality factors. There was also no evidence that the treatments caused oestrogenic stimulation of the endometrium (an adverse effect) when used for up to two years.

AUTHORS' CONCLUSIONS

There is no evidence of effectiveness in the alleviation of menopausal symptoms with the use of phytoestrogen treatments.

Isoflavones--safe food additives or dangerous drugs?

The sales volume of products containing isoflavone has increased since the publication of the Women's Health Initiative. The many apparently contradictory results published on the effects of isoflavones on a variety of estrogen-regulated organs point to both beneficial as well as adverse effects on human health. It is of particular importance that psychovegetative climacteric complaints such as hot flushes are, if at all, only slightly influenced by isoflavones. The substances appear to have weak anti-osteoporotic effect. Their anti-atherosclerotic action is debatable, as not all authors find any beneficial effect on lipids. Most importantly, there is dispute as to whether isoflavones derived from soy or red clover have negative, positive or any effect at all on the mammary gland or endometrium. It is beyond any doubt that soy products may have cancer preventing properties in a variety of organs including the mammary gland. However, these properties may only be exerted if the developing organ was under the influence of isoflavones during childhood and puberty. This may also explain the often quoted "Japanese Phenomenon", the fact that breast cancer occurs to a lesser extent in Japanese women. When administered to isoflavone "inexperienced" women at the time of menopause, the phytoestrogens appear to share the same effects as estrogen used in classical preparations for hormone replacement therapy, i.e. they may stimulate the proliferation of endometrial and mammary gland tissue with at present unknown and unpredictable risk to these organs. Therefore, the following question arises for the clinician: Why should soy or red clover products containing isoflavone be recommended, if the positive effects are only negligible but the adverse effects serious?

Effects of soy isoflavone supplementation on cognitive function in Chinese postmenopausal women: a double-blind, randomized, controlled trial

OBJECTIVE

To investigate whether soy-derived isoflavone extract improves performance in cognitive function and quality of life in Chinese postmenopausal women.

DESIGN

The study was a 6-month double-blind, randomized, placebo-controlled, parallel group trial. Participants were community-dwelling women aged 55 to 76 years; 191 eligible women were randomly assigned to receive a daily oral intake of 80 mg soy-derived isoflavones or an identical-appearing placebo for 6 months. Standardized neuropsychological tests of memory, executive function, attention, motor control, language, and visual perception and a global cognitive function assessment were administered face-to-face individually at baseline and at 6-months posttreatment. The validated Chinese version of the Short Form-36 was used for quality of life measurements.

RESULTS

Of the participants, 88% (168 women: 80 among the supplementation group and 88 among the placebo group) completed the trial. Intention-to-treat analysis, conducted for 176 participants with 6-month assessment results, revealed no significant differences in outcome measures between treatment groups. Subgroup analysis among the good compliers only (consumed at least 80% of the supplements or placebo; n = 168) and among the age groups younger or older than 65 years also indicated no significant differences for any outcome measures. Types of complaints of adverse events were similar in both treatment groups and included mainly gastrointestinal and musculoskeletal problems.

CONCLUSIONS

This 6-month trial indicates that 80-mg soy-derived isoflavone supplementation did not improve performance on standard neuropsychological tests and overall quality of life in generally healthy Chinese postmenopausal women.

Enhanced estrogenic responses and sensitivity to azoxymethane following dietary soy isoflavone supplementation in older female rats

Soy isoflavones are popular supplements among middle-aged and older women based on their potential protection against cancer and their use as alternative hormone replacement therapy. The purpose of this study was to investigate the effects of dietary soy isoflavones on early stage colon cancer in various ages of female rats. Young (1month), mature (11month) and old (22month) female Fisher 344 rats were fed either the control diet or a diet containing 0.4% soy isoflavone isolate for 1week, injected once with 20mg/kg azoxymethane (AOM) and maintained on the diets for another 15weeks. The concentration of isoflavones in the diet was 2g/kgdiet, composed of 1.2g/kg genistin, 0.7g/kg daidzin and 0.1g/kg other isoflavones including glycitin, acetylgenistin, acetyldaidzin, genistein, daidzein, and glycitein. There was no difference over all ages in the development of preneoplastic colonic aberrant crypt foci between rats fed the soy compared to the control diet, indicating that the soy diet did not provide protection against early stage colonic carcinogenesis. On the contrary, several adverse effects of soy supplementation in female AOM-treated rats were observed. Soy-supplemented rats had greater weight loss and a slower recovery of body weight following the AOM injection compared to rats fed the control diet and these changes increased with age. Five of the 21 rats fed the soy supplement died before the end of the experiment while all animals on the control diet survived to term. The density of normal crypts lining the colonic mucosa was reduced in rats fed the soy compared to control diet, indicating gastrointestinal damage. Uterine weights, serum estradiol and serum isoflavone levels were increased in mature and old female rats fed the soy-supplemented diets compared to age-matched controls, suggesting an increasing estrogenic response with age to isoflavone supplementation. These adverse effects of soy isoflavones in aged female animals need further examination because women, and particularly older women, are the prime target population for consumption of soy supplements.

Is there an estrogenic component in the metabolic syndrome?

One of the major upcoming concerns leading to health related problems in the industrialized societies is the metabolic syndrome which is characterized by central obesity, hypertension, raised fasting glucose and triglyceride levels. The focus of this review is on a potential estrogenic linkage between the metabolic mechanisms involved into the development of this disease cluster and specific estrogen related regulatory pattern. The candidate molecules for this link are insulin and insulin-like growthfactor, C-reactive protein, peroxisome-proliferation-activatingreceptorgamma, and leptin which all seem to interact with each other and show a responsiveness to changing estrogen levels. From this perspective they might also represent target molecules for a phytochemical intervention with phytoestrogens.

A randomized controlled trial of the effect of dietary soy and flaxseed muffins on quality of life and hot flashes during menopause

OBJECTIVE

To compare the effects of daily ingestion of soy flour (S), ground flaxseed (F), or wheat flour (W) muffins, on quality of life and hot flash frequency and severity in postmenopausal women.

DESIGN

This was a double-blind, randomized, controlled, intention-to-treat trial. Ninety-nine women, 1 to 8 years after menopause, ingested muffins with 25 g of flaxseed (50 mg of lignans), 25 g of soy (42 mg of isoflavones), or wheat (control) daily for 16 weeks. Subjects completed the Menopause-specific Quality of Life instrument monthly along with daily hot flash frequency and severity diaries. Compliance measures included a 3-day food diary and urinary isoflavone and lignan analyses at weeks 0 and 16 and returned muffin counts monthly.

RESULTS

Eighty-seven women (28, ground flaxseed muffins; 31, soy flour muffins; and 28, wheat flour muffins) completed the trial. Multivariate analysis of variance of all quality-of-life domains yielded an insignificant treatment x time interaction (F46,122 = 0.92, P = 0.62) but a significant time main effect (P <.0001). Repeated-measures analyses of covariance controlling for body mass index showed no significant group x time interaction nor time nor group differences on all quality-of-life domains and hot flash measures except severity. Hot flashes were less severe with flaxseed (P = 0.001) compared to placebo; however, the group x by time interaction was not significant. Phytoestrogen excretion analysis showed treatment group exposure as allocated and no contamination.

CONCLUSION

Neither dietary flaxseed nor soy flour significantly affected menopause-specific quality of life or hot flash symptoms in this study.

Finished herbal product as an alternative treatment for menopausal symptoms in climacteric women

BACKGROUND

There is a paucity of scientific evidence supporting the efficacy of herbal medicines in treating menopausal symptoms.

OBJECTIVE

The aim of this study was to evaluate safety and efficacy of the finished herbal product TMN-1 in the treatment of menopausal symptoms in climacteric women.

DESIGN AND SETTING

A multicenter, prospective, observational follow-up study was conducted from July 2003 to December 2004 in four hospitals in Taiwan.

PARTICIPANTS

Initially, 126 women were included who were between 45 and 55 years of age, were experiencing hot flashes, and were without hormone replacement therapy. Women were excluded if they had any signs of active cancer. Of the participants, 82% completed the study. The reasons for withdrawal included adverse effects (n = 7), failed to return (n = 7), lack of efficacy (n = 6), and from protocol deviation (n = 3).

INTERVENTION

Every participant received TMN-1 treatment 4 g, 3 times per day, for 12 weeks.

MAIN OUTCOME MEASURE

Primary measures were change in frequency of hot flashes and severity of menopausal symptoms measured by Kupperman Index (KI). Secondary outcomes included changes in quality of life and adverse events.

RESULTS

Significant improvement in scores of hot flashes and KI were found at weeks 4 and 12 in the 50 peri- and 53 postmenopausal women who completed this study (p < 0.001). Logistic regression analyses showed that perimenopausal women with hot flashes had sevenfold (95% confidence interval [CI], 1.8-28.0) odds of improvement in favor of treatment, whereas that of the postmenopausal group was 1.5 (95% CI, 0.5 to 4.2). Further analyses showed that TMN-1 produced superior benefit in women with moderate and severe menopausal symptoms (KI > or = 21), compared to those with mild symptoms. It also improved symptoms of insomnia, nervousness, melancholia, and palpitation in perimenopausal women. Five (5) adverse drug reactions were detected: three single events of nausea, abdominal pain, and abdominal fullness; and two events of diarrhea.

CONCLUSIONS

This study provides evidence that 12 weeks of TMN-1 therapy is a viable alternative treatment to consider in perimenopausal women with hot flashes, particularly in those with palpitations, emotional disturbance, and insomnia.