Gabapentin vs. low-dose transdermal estradiol for treating post-menopausal women with moderate to very severe hot flushes

Systematic review and network meta-analysis comparing the efficacy of fezolinetant with hormone and nonhormone therapies for treatment of vasomotor symptoms due to menopause

IMPORTANCE

The neurokinin 3 receptor antagonist fezolinetant 45 mg/d significantly reduced frequency/severity of moderate to severe vasomotor symptoms (VMS) of menopause compared with placebo in two phase 3 randomized controlled trials. Its efficacy relative to available therapies is unknown.

OBJECTIVE

We conducted a systematic review and Bayesian network meta-analysis to compare efficacy with fezolinetant 45 mg and hormone therapy (HT) and non-HT for VMS in postmenopausal women.

EVIDENCE REVIEW

Using OvidSP, we systematically searched multiple databases for phase 3 or 4 randomized controlled trials in postmenopausal women with ≥7 moderate to severe VMS per day or ≥50 VMS per week published/presented in English through June 25, 2021. Mean change in frequency and severity of moderate to severe VMS from baseline to week 12 and proportion of women with ≥75% reduction in VMS frequency at week 12 were assessed using fixed-effect models.

FINDINGS

The network meta-analysis included data from the pooled phase 3 fezolinetant trials plus 23 comparator publications across the outcomes analyzed (frequency, 19 [34 regimens]; severity, 6 [7 regimens]; ≥75% response, 9 [15 regimens]). Changes in VMS frequency did not differ significantly between fezolinetant 45 mg and any of the 27 HT regimens studied. Fezolinetant 45 mg reduced the frequency of moderate to severe VMS events per day significantly more than all non-HTs evaluated: paroxetine 7.5 mg (mean difference [95% credible interval {CrI}], 1.66 [0.63-2.71]), desvenlafaxine 50 to 200 mg (mean differences [95% CrI], 1.12 [0.10-2.13] to 2.16 [0.90-3.40]), and gabapentin ER 1800 mg (mean difference [95% CrI], 1.63 [0.48-2.81]), and significantly more than placebo (mean difference, 2.78 [95% CrI], 1.93-3.62]). Tibolone 2.5 mg (the only HT regimen evaluable for severity) significantly reduced VMS severity compared with fezolinetant 45 mg. Fezolinetant 45 mg significantly reduced VMS severity compared with desvenlafaxine 50 mg and placebo and did not differ significantly from higher desvenlafaxine doses or gabapentin ER 1800 mg. For ≥75% responder rates, fezolinetant 45 mg was less effective than tibolone 2.5 mg (not available in the United States) and conjugated estrogens 0.625 mg/bazedoxifene 20 mg (available only as 0.45 mg/20 mg in the United States), did not differ significantly from other non-HT regimens studied and was superior to desvenlafaxine 50 mg and placebo.

CONCLUSIONS

The only HT regimens that showed significantly greater efficacy than fezolinetant 45 mg on any of the outcomes analyzed are not available in the United States. Fezolinetant 45 mg once daily was statistically significantly more effective than other non-HTs in reducing the frequency of moderate to severe VMS.

RELEVANCE

These findings may inform decision making with regard to the individualized management of bothersome VMS due to menopause.

Recent Advancement of Medical Patch for Transdermal Drug Delivery

Transdermal patches are a non-invasive method of drug administration. It is an adhesive patch designed to deliver a specific dose of medication through the skin and into the bloodstream throughout the body. Transdermal drug delivery has several advantages over other routes of administration, for instance, it is less invasive, patient-friendly, and has the ability to bypass first-pass metabolism and the destructive acidic environment of the stomach that occurs upon the oral ingestion of drugs. For decades, transdermal patches have attracted attention and were used to deliver drugs such as nicotine, fentanyl, nitroglycerin, and clonidine to treat various diseases or conditions. Recently, this method is also being explored as a means of delivering biologics in various applications. Here, we review the existing literatures on the design and usage of medical patches in transdermal drug delivery, with a focus on the recent advances in innovation and technology that led to the emergence of smart, dissolvable/biodegradable, and high-loading/release, as well as 3D-printed patches.

Pharmacotherapeutic options for the treatment of menopausal symptoms

Introduction: Menopausal symptoms can be very overwhelming for women. Over the years, many pharmacotherapeutic options have been tested, and others are still being developed. Hormone therapy (HT) is the most efficient therapy for managing vasomotor symptoms and related disturbances. The term HT comprises estrogens and progestogens, androgens, tibolone, the tissue-selective estrogen complex (TSEC), a combination of bazedoxifene and conjugated estrogens, and the selective estrogen receptor modulators, such as ospemifene. Estrogens and progestogens and androgens may differ significantly for chemical structure and can be delivered through different routes, thereby displaying various pharmacological and clinical properties. Tibolone, TSEC and SERM also exhibit unique pharmacodynamics that can be exploited to obtain distinctive therapeutic effects. Non-hormonal options fall mainly into the selective serotonin reuptake inhibitor (SSRI) and selective noradrenergic reuptake inhibitor (SNRI), GABA-analogue drug classes.Areas covered: Herein, the authors describe the pharmacokinetics and pharmacodynamics of hormonal (androgens, estrogens, progestogens, tibolone, TSEC, SERMs) and non-hormonal (SSRIs, SNRIs, Gabapentin, Pregabalin, Oxybutynin, Neurokinin antagonists) treatments for menopausal symptoms and report essential clinical trial data in humans.Expert opinion: Patient tailoring of treatment is key to managing symptoms of menopause. Physicians must have in-depth knowledge of the pharmacology of compounds to tailor therapy to the individual patient's characteristics and needs.

Efficacy and safety of gabapentin and pregabalin in patients with vasomotor symptoms: a systematic review and meta-analysis

OBJECTIVE

Vasomotor symptoms are common among postmenopausal women and patients receiving hormone deprivation therapies, and emerging studies are exploring gabapentin's and pregabalin's effects as nonhormonal treatment options. We aimed to assess the efficacy and safety of these 2 drugs.

DATA SOURCES

Based on a preregistered protocol (Prospective Register of Systematic Reviews -CRD42019133650), we searched 10 databases (PubMed, Embase, Web of Science, PsycINFO, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Chinese Biological Medical Literature, Chinese National Knowledge Infrastructure, Chinese Journals Full-text Database [VIP], and Wanfang) as well as the World Health Organization international clinical trials registry platform and reference lists of related literatures.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials and randomized crossover studies exploring gabapentin and pregabalin among women patients with vasomotor symptoms were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement was followed. Two reviewers independently selected studies, assessed bias, and extracted data. Mean difference and standardized mean difference with 95% confidence intervals were assessed by random-effects models. Heterogeneities were assessed by I² statistics, and the quality of evidence was evaluated by the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

Nineteen randomized controlled trials and 2 randomized crossover trials reporting results from 3519 participants were included. Gabapentin could reduce hot flash frequency (mean difference, -1.62, 95% confidence interval, -1.98 to -1.26 after 4 weeks; mean difference, -2.77, 95% confidence interval, -4.29 to -1.24 after 12 weeks) and composite score (standardized mean difference, -0.47, 95% confidence interval, -0.71 to -0.23 after 4 weeks; standardized mean difference, -0.77, 95% confidence interval, -1.15 to -0.40 after 12 weeks) compared with placebo. Both menopausal participants and patients with breast cancer benefited from treatment. Higher risks of dizziness and somnolence were found in the gabapentin group than in the control group (risk ratio, 4.45, 95% confidence interval, 2.50-7.94; risk ratio, 3.29, 95% confidence interval, 1.97-5.48, respectively). Estrogen was more effective in reducing hot flash frequency than gabapentin. No statistically significant difference in reduction of hot flash severity score was found between gabapentin and antidepressants. The trials comparing gabapentin or pregabalin with the other interventions were too limited to make a conclusion.

CONCLUSION

Favorable effects of gabapentin in relieving vasomotor symptoms were observed, compared with controls, but were less effective than those of estrogen. Evidence supporting the therapeutic effect of pregabalin is still lacking.

Gabapentin for the treatment of hot flushes in menopause: a meta-analysis

OBJECTIVE

Gabapentin is used to treat vasomotor symptoms (VMS) in postmenopausal women with contraindications to hormonal therapy or who prefer alternatives. We investigated the efficacy and tolerability of gabapentin for treating menopausal hot flushes via a meta-analysis.

METHODS

We searched the PubMed, MEDLINE, EMBASE, and CENTRAL databases for English-language articles published until June, 2018. The following search terms were used: "menopause," "hot flushes," "vasomotor symptoms," "gabapentin," and "non-hormonal therapy." Primary outcomes were frequency, duration, and composite score of hot flushes. Secondary outcomes were adverse effects and dropout rate. We estimated the standardized mean difference (SMD) and combined odds ratio (OR) using fixed or random-effects models, depending on study heterogeneity. Subgroup and meta-regression analyses of gabapentin dosage were performed.

RESULTS

We included seven randomized controlled trials that compared single-agent gabapentin with placebo for treating hot flushes in the meta-analysis. Women who received gabapentin reported a significantly greater reduction in the frequency (SMD 2.99 [95% confidence interval 2.01-3.98], P < 0.001), duration (0.89 [0.49-1.30], P < 0.001), and composite score (2.31 [1.50-3.11], P < 0.001) of hot flushes. Adverse events were significantly more frequent among those taking gabapentin than among those taking the placebo (OR 1.58 [0.98-2.18], P < 0.001; and 1.19 [0.43-1.95], P = 0.002 for dizziness and unsteadiness, respectively).

CONCLUSIONS

Gabapentin could be used to treat VMS in postmenopausal women with contraindications to hormonal therapy. Future studies should investigate the lowest effective dose of gabapentin to minimize adverse effects. : Video Summary:http://links.lww.com/MENO/A521.

Variation in menopausal vasomotor symptoms outcomes in clinical trials: a systematic review

BACKGROUND

There is substantial variation in how menopausal vasomotor symptoms are reported and measured among intervention studies. This has prevented meaningful comparisons between treatments and limited data synthesis.

OBJECTIVES

To review systematically the outcome reporting and measures used to assess menopausal vasomotor symptoms from randomised controlled trials of treatments.

SEARCH STRATEGY

We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception to May 2018.

SELECTION CRITERIA

Randomised controlled trials with a primary outcome of menopausal vasomotor symptoms in women and a sample size of at least 20 women per study arm.

DATA COLLECTION AND ANALYSIS

Data about study characteristics, primary vasomotor-related outcomes and methods of measuring them.

MAIN RESULTS

The search identified 5591 studies, 214 of which were included. Forty-nine different primary reported outcomes were identified for vasomotor symptoms and 16 different tools had been used to measure these outcomes. The most commonly reported outcomes were frequency (97/214), severity (116/214), and intensity (28/114) of vasomotor symptoms or a composite of these outcomes (68/214). There was little consistency in how the frequency and severity/intensity of vasomotor symptoms were defined.

CONCLUSIONS

There is substantial variation in how menopausal vasomotor symptoms have been reported and measured in treatment trials. Future studies should include standardised outcome measures which reflect the priorities of patients, clinicians, and researchers. This is most effectively achieved through the development of a Core Outcome Set. This systematic review is the first step towards development of a Core Outcome Set for menopausal vasomotor symptoms.

TWEETABLE SUMMARY

Menopausal hot flushes and night sweats have been reported in 49 different ways in clinical research. A core outcome set is urgently required.

MANAGEMENT OF ENDOCRINE DISEASE: Flushing: current concepts

OBJECTIVE

Flushing can be defined as a sensation of warmth accompanied by erythema that most commonly is seen on the face and which occurs in episodic attacks. Such a problem can be clinically problematic, since many conditions and drugs can be related to flushing, and while often there appears to be no underlying organic disease, it is important to exclude disorders since they may be life-threatening conditions.

DESIGN AND METHODS

We performed a search in MEDLINE using the terms 'flushing' in combination with 'carcinoid syndrome', 'pheochromocytoma', 'mastocytosis', 'menopausal hot flush' and 'treatment'. European and American guidelines relating to neuroendocrine tumours, mastocytosis and menopause were reviewed.

RESULTS

In this review, we discuss the main causes of flushing and propose an algorithm based on pathogenesis, which can be used to guide the clinical evaluation process. We also review recent significant developments in the assessment and treatment of the carcinoid syndrome and menopausal hot flushes, which should guide the clinical practice regarding this common but sometimes confusing condition.

CONCLUSIONS

When evaluating flushing, a precise systematic approach is needed to exclude potentially serious underlying causes, although despite this, the cause of the disorder is not always found. If symptoms are not progressive, the patient should be advised about its apparently benign nature in order to avoid unnecessary studies or initiating treatments of minimal benefit.

Nonhormonal management of menopause-associated vasomotor symptoms: 2015 position statement of The North American Menopause Society

OBJECTIVE

To update and expand The North American Menopause Society's evidence-based position on nonhormonal management of menopause-associated vasomotor symptoms (VMS), previously a portion of the position statement on the management of VMS.

METHODS

NAMS enlisted clinical and research experts in the field and a reference librarian to identify and review available evidence. Five different electronic search engines were used to cull relevant literature. Using the literature, experts created a document for final approval by the NAMS Board of Trustees.

RESULTS

Nonhormonal management of VMS is an important consideration when hormone therapy is not an option, either because of medical contraindications or a woman's personal choice. Nonhormonal therapies include lifestyle changes, mind-body techniques, dietary management and supplements, prescription therapies, and others. The costs, time, and effort involved as well as adverse effects, lack of long-term studies, and potential interactions with medications all need to be carefully weighed against potential effectiveness during decision making.

CONCLUSIONS

Clinicians need to be well informed about the level of evidence available for the wide array of nonhormonal management options currently available to midlife women to help prevent underuse of effective therapies or use of inappropriate or ineffective therapies. Recommended: Cognitive-behavioral therapy and, to a lesser extent, clinical hypnosis have been shown to be effective in reducing VMS. Paroxetine salt is the only nonhormonal medication approved by the US Food and Drug Administration for the management of VMS, although other selective serotonin reuptake/norepinephrine reuptake inhibitors, gabapentinoids, and clonidine show evidence of efficacy. Recommend with caution: Some therapies that may be beneficial for alleviating VMS are weight loss, mindfulness-based stress reduction, the S-equol derivatives of soy isoflavones, and stellate ganglion block, but additional studies of these therapies are warranted. Do not recommend at this time: There are negative, insufficient, or inconclusive data suggesting the following should not be recommended as proven therapies for managing VMS: cooling techniques, avoidance of triggers, exercise, yoga, paced respiration, relaxation, over-the-counter supplements and herbal therapies, acupuncture, calibration of neural oscillations, and chiropractic interventions. Incorporating the available evidence into clinical practice will help ensure that women receive evidence-based recommendations along with appropriate cautions for appropriate and timely management of VMS.

Alternative Medications for Medications in the Use of High-Risk Medications in the Elderly and Potentially Harmful Drug-Disease Interactions in the Elderly Quality Measures

The National Committee for Quality Assurance (NCQA) and the Pharmacy Quality Alliance (PQA) use the American Geriatrics Society (AGS) Beers Criteria to designate the quality measure Use of High-Risk Medications in the Elderly (HRM). The Centers for Medicare and Medicaid Services (CMS) use the HRM measure to monitor and evaluate the quality of care provided to Medicare beneficiaries. NCQA additionally uses the AGS Beers Criteria to designate the quality measure Potentially Harmful Drug-Disease Interactions in the Elderly. Medications included in these measures may be harmful to elderly adults and negatively affect a healthcare plan's quality ratings. Prescribers, pharmacists, patients, and healthcare plans may benefit from evidence-based alternative medication treatments to avoid these problems. Therefore the goal of this work was to develop a list of alternative medications to those included in the two measures. The authors conducted a comprehensive literature review from 2000 to 2015 and a search of their personal files. From the evidence, they prepared a list of drug-therapy alternatives with supporting references. A reference list of nonpharmacological approaches was also provided when appropriate. NCQA, PQA, the 2015 AGS Beers Criteria panel, and the Executive Committee of the AGS reviewed the drug therapy alternatives and nonpharmacological approaches. Recommendations by these groups were incorporated into the final list of alternatives. The final product of drug-therapy alternatives to medications included in the two quality measures and some nonpharmacological resources will be useful to health professionals, consumers, payers, and health systems that care for older adults.

Hormonal and nonhormonal treatment of vasomotor symptoms

This article focuses on the cause, pathophysiology, differential diagnosis of, and treatment options for vasomotor symptoms. In addition, it summarizes important points for health care providers caring for perimenopausal and postmenopausal women with regard to health maintenance, osteoporosis, cardiovascular disease, and vaginal atrophy. Treatment options for hot flashes with variable effectiveness include systemic hormone therapy (estrogen/progestogen), nonhormonal pharmacologic therapies (selective serotonin reuptake inhibitors, selective norepinephrine reuptake inhibitors, clonidine, gabapentin), and nonpharmacologic therapy options (behavioral changes, acupuncture). Risks and benefits as well as contraindications for hormone therapy are further discussed.

Is desvenlafaxine effective and safe in the treatment of menopausal vasomotor symptoms? A meta-analysis and meta-regression of randomized double-blind controlled studies

BACKGROUND

During perimenopause, vasomotor symptoms are known to have a detrimental effect on women's functional ability and quality of life. For symptomatic women not eligible for hormonal therapy, desvenlafaxine is an option, but its safety margin and tolerability are not yet determined.

METHODS

A computer-based literature search was done in the databases of MEDLINE, Cochrane library, and HINARI (Health InterNetwork Access to Research Initiative). Meta-analysis was conducted by including double-blind randomized controlled studies on the effectiveness and safety of desvenlafaxine in the treatment of hot flashes. The effectiveness, safety and tolerability of desvenlafaxine were determined by standardized mean differences (SMDs) and Mantel-Haenszel odds ratio. Subgroup analysis based on doses of desvenlafaxine and linear meta-regression analyses were performed for several covariates. Heterogeneity testing, the risk of bias assessment and sensitivity analyses were done.

RESULTS

Desvenlafaxine was associated with a statistically significant reduction in the number and severity of daily moderate to severe hot flashes. The number of nighttime awakenings because of hot flashes was also significantly decreased. However, the rate of desvenlafaxine treatment discontinuation because of adverse events was a significantly higher than placebo treated women and the risk ratios of adverse events like asthenia, hypertension, anorexia, constipation, diarrhea, dry mouth, nausea, dizziness, insomnia, somnolence and mydriasis were very high.

CONCLUSION

Desvenlafaxine is effective in the treatment of hot flashes but it is strongly associated with several adverse events and treatment discontinuation. Further clinical trials focusing only on desvenlafaxine related adverse events are highly warranted before it is approved for public use.

ACOG Practice Bulletin No. 141: management of menopausal symptoms

Vasomotor and vaginal symptoms are cardinal symptoms of menopause. Vasomotor symptoms can be particularly troubling to women and are the most commonly reported menopausal symptoms, with a reported prevalence of 50-82% among U.S. women who experience natural menopause (1, 2). The occurrence of vasomotor symptoms increases during the transition to menopause and peaks approximately 1 year after the final menstrual period (3-5). The purpose of this document is to provide evidence-based guidelines for the treatment of vasomotor and vaginal symptoms related to natural and surgical menopause. (Treatment of menopausal symptoms in cancer survivors is discussed in the American College of Obstetricians and Gynecologists' Practice Bulletin Number 126, Management of Gynecologic Issues in Women With Breast Cancer.).

Risk factors, pathophysiology, and treatment of hot flashes in cancer

Hot flashes are prevalent and severe symptoms that can interfere with mood, sleep, and quality of life for women and men with cancer. The purpose of this article is to review existing literature on the risk factors, pathophysiology, and treatment of hot flashes in individuals with cancer. Electronic searches were conducted to identify relevant English-language literature published through June 15, 2012. Results indicated that risk factors for hot flashes in cancer include patient-related factors (eg, age, race/ethnicity, educational level, smoking history, cardiovascular risk including body mass index, and genetics) and disease-related factors (eg, cancer diagnosis and dose/type of treatment). In addition, although the pathophysiology of hot flashes has remained elusive, these symptoms are likely attributable to disruptions in thermoregulation and neurochemicals. Therapies that have been offered or tested fall into 4 broad categories: pharmacological, nutraceutical, surgical, and complementary/behavioral strategies. The evidence base for this broad range of therapies varies, with some treatments not yet having been fully tested or showing equivocal results. The evidence base surrounding all therapies is evaluated to enhance hot flash treatment decision-making by clinicians and patients.

Comparison of Gabapentin with Estrogen for treatment of hot flashes in post-menopausal women

OBJECTIVE

Various non-hormonal agents have been used for the treatment of hot flashes in women with menopause. Some studies have reported that gabapentin appears to be an effective and well-tolerated treatment modality. The aim of this study was to evaluate whether the treatment with gabapentin is effective in reducing hot flash frequency and severity and also to compare gabapentin 100 mg/day, 300 mg/day and conjugated estrogen in this regards.

METHODS

In this comparative clinical trial, 100 post-menopausal women attending outpatient clinics of Isfahan University hospitals were included from April 2008 to February 2009. Participants randomly received gabapentin 300 mg/day, gabapentin 100 mg/day, or conjugated estrogen 0.625 mg/day for 12 weeks. Frequency and severity of hot flashes and adverse effects were compared among the three groups.

FINDINGS

From all, 16 participants dropped out. There were no significant differences among the groups before intervention in terms of age, body mass index and baseline hot flash frequency and severity. Hot flash diaries were used to record the frequency and severity of hot flashes. After the treatment period, there was a significant decrease in both severity and frequency of hot flashes in all three groups. Post-hoc analyses showed that the frequency and severity of hot flashes were significantly lower in those who received gabapentin 300 mg/day or estrogen 0.625 mg/day compared to those who received gabapentin 100 mg/day. There was not statistically significant difference between those who received gabapentin 300 mg/day and those who received estrogen. Very few adverse effects, mostly gastrointestinal discomfort were observed in both gabapentin groups (8%).

CONCLUSION

Gabapentin 300 mg/day could be useful to relieve hot flashes in women for whom hormone therapy is not suitable or when hot flashes do not respond to other therapies. Further researches are needed to determine the efficacy of gabapentin use for longer periods or at higher doses.

Alternative and complementary therapies for the menopause

Despite a re-evaluation of risks in recent years, hormone replacement therapy is still surrounded by controversy. Almost 30% of women in a recent survey sought a natural approach to combat climacteric symptoms. Nevertheless, a large proportion of patients felt that they wanted a good safety profile and strong evidence base for treatment. This article seeks to review the evidence supporting non-hormonal approaches to treatment. There is only conflicting evidence at best to support alpha-2 agonists, e.g. clonidine and limited evidence for dihydroepiandrosterone and natural progesterones. There is limited randomized controlled trial data for gabapentin, selective norepinephrine re-uptake inhibitors (SNRIs) and selective serotonin re-uptake inhibitors (SSRIs), many of these studies being related to breast cancer patients. Of the herbal medicinal products, the largest evidence base rests with phytoestrogens. A Cochrane Database review looking at all types of phytoestrogens, e.g. red clover extracts, dietary soya and soya extracts concluded that there was no evidence to support improvement in climacteric symptoms and the meta-analysis of a 178 studies on soy products was inconsistent. Nevertheless, other studies disagree. Mammographic density is not affected by soy or phytoestrogen products and recent in vitro work shows only a weakly proliferative effect of soy isoflavone on breast cancer cells and evidence that soy isoflavone blocks the proliferative effect of estradiol on these cells. There are no studies looking at clinical outcome measures for cardiovascular disease but a number of studies looking at biochemical markers including arterial wall stiffness and apolipo protein B. Recent studies have also looked at the effects of red clover isoflavone on mood and depression, using specific depression rating scales. Finally, it is important to note that herbal medicinal products should not be used without caution. Some may produce quite marked side-effects in high doses and others can interact with pre-existing medication. A strategy for which patients are suitable for herbal medicinal products is reviewed.

Menopausal hot flushes and night sweats: where are we now?

OBJECTIVE

An overview of the current knowledge on the etiology and treatment of vasomotor symptoms in postmenopausal women.

MATERIALS AND METHODS

Acknowledged experts in the field contributed a brief assessment of their areas of interest which were combined and edited into the final manuscript.

RESULTS

Women around the world experience vasomotor symptoms as they enter and complete the menopause transition. Vasomotor symptoms, specifically hot flushes, are caused by a narrowing of the thermoneutral zone in the brain. This effect, although related to estrogen withdrawal, is most likely related to changes in central nervous system neurotransmitters. Peripheral vascular reactivity is also altered in symptomatic women. Estrogen replacement therapy is the most effective treatment for hot flushes. Of the other interventions investigated, selective serotonin and selective norepinephrine reuptake inhibitors and gabapentin show efficacy greater than placebo. Objective monitoring of hot flushes indicates a robust improvement with hormone replacement therapy but little to no change with placebo. These data suggest that the subjective assessment of responses to therapy for vasomotor symptom results in inaccurate data. Hot flushes have recently been associated with increased cardiovascular risks and a lower incidence of breast cancer, but these data require confirmation.

CONCLUSIONS

Vasomotor symptoms are experienced by women of all ethnic groups. They are caused by changes in the central nervous system associated with estrogen withdrawal and are best treated with estrogen replacement therapy. Objective monitoring of hot flushes indicates that placebo has little to no effect on their improvement. Subjective assessments of hot flushes in clinical trials may be inaccurate based on objective measurement of the frequency of hot flushes. Based on preliminary reports, women experiencing hot flushes have an increased risk of cardiovascular disease and a reduced incidence of breast cancer.

Assessing risks and benefits of nonhormonal treatments for vasomotor symptoms in perimenopausal and postmenopausal women

BACKGROUND

Vasomotor symptoms (VMS); (hot flushes and night sweats) are the most common menopausal complaint for which women seek treatment. Several therapies can be considered to help manage these complaints. The objective of this review is to assess the risks and benefits of available and emerging therapeutic options for the management of menopausal VMS.

METHODS

A review of the literature was conducted based on relevant publications identified through a PubMed search for clinical trials of agents used in the treatment of VMS.

RESULTS

Hormone therapy (HT) remains the most effective treatment available, but there will always remain a need for nonhormonal options. Evidence does not support the efficacy of alternative or over-the-counter products, such as phytoestrogens and black cohosh, and their long-term safety is largely unknown. There is evidence supporting the efficacy of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) for the management of VMS from clinical trials of paroxetine, venlafaxine, and desvenlafaxine. Gabapentin appears to be effective, but the doses required may cause poor tolerability and reduced patient adherence. Data also suggest that clonidine has a modest effect at the expense of considerable adverse effects.

CONCLUSIONS

Choosing an appropriate treatment approach for the management of VMS requires careful assessment of the riskbenefit ratio of each alternative, as well as individual patient preference.

Use of gabapentin for the management of natural or surgical menopausal hot flashes

OBJECTIVE

To review the literature examining the use of gabapentin for treatment of hot flashes during natural or surgically induced menopause.

DATA SOURCES

A literature search was conducted via PubMed, MEDLINE, and International Pharmaceutical Abstracts (1948-November 2010) using the search terms gabapentin, hot flashes, and menopause. Literature was limited to English-language, human studies. Additional material was identified by reviewing reference citations of the articles retrieved.

STUDY SELECTION AND DATA EXTRACTION

Studies with data describing gabapentin for hot flash management during natural or surgically induced menopause were included. Any studies including women with a history of breast cancer were excluded. Four studies met the inclusion criteria.

DATA SYNTHESIS

Gabapentin significantly decreased hot flash frequency and hot flash composite scores by 45-71% from baseline in the 4 trials included in this review. In 2 of the trials, gabapentin was comparable to hormone replacement therapy (71% vs 72%, respectively, p=0.63) in decreasing hot flash composite scores at the end of 12 weeks and in decreasing hot flash frequency at the end of 8 weeks (58.9% vs 70.1%, p>0.05). In all trials, the most common adverse effects with gabapentin were somnolence/drowsiness, unsteadiness, and dizziness. These adverse effects were most pronounced during the first 1-2 weeks of therapy, but resolved and were similar to those reported with placebo by week 4. These trials were short (<12 weeks) and had small sample sizes; however, their results appear to show that gabapentin is safe and effective for short-term treatment of hot flashes in women who have entered menopause either naturally or surgically.

CONCLUSIONS

Gabapentin 600-2400 mg/day in divided doses may be a viable option for treating hot flashes in menopausal women who do not want to use hormone replacement therapy.

The Cimicifuga racemosa special extract BNO 1055 prevents hot flashes in ovariectomized rats

Hot flashes are a disorder of thermoregulation due to the lack of estrogens and are the most common and characteristic climacteric complaint. Hormone replacement therapy is the gold standard treatment but now its use is limited due to several side effects. Need therefore arises to search for non-estrogenic alternatives. It is well established that extracts of Cimicifuga racemosa (CR) ease climacteric complaints but solid animal experimental data supporting such effects are not available. The availability of sensitive transponders which record subcutaneous temperature continuously enables nowadays experiments in rats to establish whether they have hot flashes following ovariectomy (Seidlova-Wuttke et al. 2003) and if so, whether they can be influenced by the extract of CR BNO 1055. Intact Sprague-Dawley rats (n=16) were acclimatized and their subcutaneous body temperature was measured in 5 min intervals and mean values from 3h recordings were calculated. Thereafter, the rats were ovx and fed either with soy free (sf) or CR BNO 1055 (25 mg/animal/day) food. Temperature was recorded again after acute and sub-acute application of CR. In individual intact animals temperature was stable over the 3h recording period. Following ovx temperature pulses appeared with peaks occurring every 20-40 min. These fluctuations were not seen in CR BNO 1055 treated animals resulting in significantly higher mean temperatures in ovx in comparison to intact or ovx CR BNO treated rats. This reduction of hot flashes by BNO 1055 outlasted the experimental period of 3 weeks. These results suggest that the ovx rats and the new temperature-sensitive device may be useful for the study of hot flashes. Furthermore the results prove that the CR BNO 1055 exerts hot flash reducing effects.