RELEVANT RESEARCH STUDIES AND ARTICLES
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Naser B, Schnitker J, Minkin MJ, de Arriba SG, Nolte KU, Osmers R. Suspected black cohosh hepatotoxicity: no evidence by meta-analysis of randomized controlled clinical trials for isopropanolic black cohosh extract. Menopause. 2011 April; 18(4): 366-375.
*Quick Summary of Study: This article explores the safety of Black Cohosh supplementation on liver function in women with menopausal systems.
Black cohosh, a popular herbal treatment for menopausal symptoms, has been implicated in a number of hepatotoxicity case reports. The purpose of this investigation was to analyze data gained from clinical trials on the effect of black cohosh on liver function.
A meta-analysis of randomized, double-blind, and controlled clinical trials was conducted. These studies primarily evaluated the efficacy and safety of the isopropanolic black cohosh extract (iCR) in perimenopausal and postmenopausal women. Raw data on liver function values of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyltranspeptidase were considered in this analysis, if these data at baseline and after 3 to 6 months of treatment were available. Standard methods of descriptive statistics were used in this analysis.
Five studies involving a total of 1,117 women were included in the meta-analyses. A total of 1,020 women (test population=517 and reference population=503) completed the studies. Perimenopausal and postmenopausal women (40-60 y) were treated daily with iCR (corresponding to 40-128 mg drug) for 3 to 6 months. The meta-analyses of the standardized mean differences in the "test" versus "reference" showed no significant effects and no differences between double-blind, placebo-controlled and other trials. The overall fixed effect ± SEM was 0.055 ± 0.062 (P=0.37) for aspartate aminotransferase and 0.063 ± 0.062 (P=0.31) for alanine aminotransferase. The nonsignificant effects concerned the overall analyses of all included studies as well as the proportion of placebo-controlled studies.
The results of this meta-analysis of five randomized, double-blind, and controlled clinical trials showed no evidence that iCR has any adverse effect on liver function
*Quick Summary of Study: Black cohosh was found to decrease menopausal symptoms in certain placebo controlled trials.
This study aimed to review the evidence on the efficacy of herbal preparations containing black cohosh for the treatment of menopausal symptoms. A systematic search of three databases (PubMed, Embase, and Cochrane library) was conducted to identify relevant literature. Two reviewers independently abstracted the data from the eligible studies. Of the 288 English language citations screened, nine randomized placebo-controlled trials were included. Among these trials, six demonstrated a significant improvement in the black cohosh group compared with the placebo group. Using data from seven trials, we calculated a combined estimate for the change in menopausal vasomotor symptoms. Preparations containing black cohosh improved these symptoms overall by 26% (95% confidence interval 11%-40%); there was, however, significant heterogeneity between these trials. Given that black cohosh is one of the most frequently used herbal medications for menopausal vasomotor symptoms in North America, more data are warranted on its effectiveness and safety.
Low Dog T. Menopause: a review of botanical dietary supplements. American Journal of Medicine. 2005 Dec 19; 118 Suppl 12B: 98-108.
*Quick Summary of Study: This article explores the effectiveness of several herbal supplements on their ability to reduce menopausal symptoms.
Since the release of the Women's Health Initiative (WHI) findings, an increasing number of dietary supplement products specifically targeting women in menopause have appeared in the American marketplace. This growth highlights the need for a critical evaluation of the tolerability and effectiveness of these products. The purpose of this article is to assess the evidence for safety and benefit of botanical monopreparations used for relief of menopause-related symptoms. The Cochrane Library and Medline databases were searched from January 1966 to October 2004, using a detailed list of terms related to botanicals and menopausal symptoms. Studies were considered eligible (1) if they were controlled trials of a botanical monopreparation administered orally for a minimum of 6 weeks to perimenopausal or postmenopausal women with hot flashes and (2) if they included a placebo or comparative treatment arm. Topical preparations, botanical combinations, and dietary interventions, such as soy food or protein, were not included. No language restrictions were imposed on the search. A total of 19 studies met the inclusion criteria. The majority of studies indicate that extract of black cohosh (Actaea racemosa L.) improves menopause-related symptoms; however, methodologic shortcomings in the trials were identified. To date, 4 case reports of possible hepatotoxicity have been published, although previous safety reviews suggest that black cohosh is well tolerated and that adverse events are rare when it is used appropriately. The results of 6 clinical studies on soy (Glycine max L.) isoflavone extracts are mixed. Moreover, the composition and dose of soy supplements varies widely across studies, making comparisons and definitive conclusions difficult. One study challenged the long-term safety of high-dose soy isoflavone extract (150 mg/day for 5 years) on the uterine endometrium. Clinical data from 5 controlled trials assessing the efficacy of semipurified isoflavone red clover (Trifolium pratense L.) leaf extracts to reduce hot flash frequency and severity or to relieve symptoms associated with the domains of the Greene Menopausal Symptom Scale are contradictory. The largest study showed no benefit for reducing symptoms associated with menopause for 2 different red clover isoflavone products compared with placebo. No significant adverse events have been reported in the literature. Single clinical trials do not support the use of dong quai (Angelica sinensis L.), ginseng (Panax ginseng C.A. Mey), or evening primrose seed oil (Oenothera biennis L.) for improving menopausal symptoms. We conclude that black cohosh extracts appear to ease menopausal symptoms; ongoing studies funded by the National Institutes of Health (NIH) will provide more definitive safety and efficacy data. Soy isoflavone extracts appear to have minimal to no effect, although definitive conclusions are difficult given the wide variation in product composition and dose. Long-term safety of higher dosage (150 mg/day) soy isoflavone extracts is uncertain. Semipurified isoflavone red clover leaf extracts have minimal to no effect in reducing menopausal symptoms. Dong quai, ginseng extract, and evening primrose seed oil appear to be ineffective in ameliorating menopausal symptoms at the dosages and in the preparations used in these studies.
4. Molla MD, Hidalgo-Mora JJ, Soteras MG.Phytotherapy as alternative to hormone replacement therapy. Front Biosci (Schol Ed). 2011 Jan 1;3:191-204.
*Quick Summary of Study: Black cohosh was shown to moderately improve vasomotor symptoms in menopausal women.
Phytoestrogens are a group of non-steroidal compounds of plant origin that present structural and functional similarities with estradiol. Isoflavones are their most widely known category. There are different mechanisms of action of isoflavones accepted, although they may be considered as selective modulators of estrogen receptors. On the other hand, Cimicifuga Racemosa is a perennial plant used traditionally for problems related to menstruation. Its action mechanisms have not been totally identified. There is a growing interest in the usefulness of phytotherapy in the treatment of symptoms and menopause-related diseases. Isoflavones and Cimicifuga Racemosa moderately improve vasomotor symptoms in menopausal women, particularly in those who have a greater number of hot flushes. Furthermore, trials performed with soy isoflavones have observed a reduction of the loss of bone mineral density in postmenopausal women and a slight decrease in LDL cholesterol. In short, phytotherapy will constitute a therapeutic option that can offer assistance to women who want to improve their quality of life through relief of vasomotor symptoms or benefit from other effects for their health.