Vitex agnus castus for premenstrual syndrome

The treatment of premenstrual syndrome with preparations of Vitex agnus castus: a systematic review and meta-analysis

BACKGROUND

Premenstrual syndrome is characterized by the cyclic occurrence of physical, behavioral and psychological symptoms during the luteal phase of the menstrual cycle disappearing within a few days of the onset of menstruation. Generally symptoms are mild, but 5-8% of women suffer from severe PMS. Apart from conventional drugs, like serotonin reuptake inhibitors and oral contraceptives, complementary and alternative medicines such as Vitex agnus castus are used by many women experiencing PMS.

OBJECTIVE

Our objective was to determine the efficacy, tolerability, and acceptability of Vitex agnus castus preparations for treatment of premenstrual syndrome.

STUDY DESIGN

All journals in the Ovid software from inception through January 2016 were searched, including the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and PsycINFO. Gray literature was searched by Google Scholar and manufacturers of Vitex agnus castus preparations were contacted for information about unpublished trials. We included randomized controlled trials with Vitex agnus castus in women with premenstrual syndrome and/or premenstrual dysphoric disorder with a minimal duration of 2 menstrual cycles. The eligibility of the manuscripts was assessed by 2 reviewers independently. The data abstracted included characteristics of the study design, characteristics of the patient population, intervention details, type of comparator, method of diagnosis, and outcome measures. We adhered to the PRISMA guidelines.

RESULTS

We found 17 randomized controlled trials of Vitex agnus castus in the treatment of premenstrual syndrome. Fourteen of these could be included in the quantitative analysis. Thirteen of 14 studies with placebo, dietary supplements, or herbal preparations as controls reported positive effects of Vitex agnus castus on total premenstrual syndrome symptoms. Unfortunately most of the trials are associated with a high risk of bias. The pooled effect of Vitex agnus castus in placebo-controlled trials was large (Hedges g, -1.21; 95% confidence interval, -1.53 to -0.88), but heterogeneity was extremely high (I², 91%). We were unable to single out factors that could explain this heterogeneity satisfactorily. The funnel plot and Egger tests suggest the presence of publication bias.

CONCLUSION

Although meta-analysis shows a large pooled effect of Vitex agnus castus in placebo-controlled trials, the high risk of bias, high heterogeneity, and risk of publication bias of the included studies preclude a definitive conclusion. The pooled treatment effects should be viewed as merely explorative and, at best, overestimating the real treatment effect of Vitex agnus castus for premenstrual syndrome symptoms. There is a clear need for high-quality trials of appropriate size examining the effect of standardized extracts of Vitex agnus castus in comparison to placebo, selective serotonin reuptake inhibitors, and oral contraceptives to establish relative efficacy.

Selective serotonin reuptake inhibitors for premenstrual syndrome

BACKGROUND

Premenstrual syndrome (PMS) is a common cause of physical, psychological and social problems in women of reproductive age. The key characteristic of PMS is the timing of symptoms, which occur only during the two weeks leading up to menstruation (the luteal phase of the menstrual cycle). Selective serotonin reuptake inhibitors (SSRIs) are increasingly used as first line therapy for PMS. SSRIs can be taken either in the luteal phase or else continuously (every day). SSRIs are generally considered to be effective for reducing premenstrual symptoms but they can cause adverse effects.

OBJECTIVES

The objective of this review was to evaluate the effectiveness and safety of SSRIs for treating premenstrual syndrome.

SEARCH METHODS

Electronic searches for relevant randomised controlled trials (RCTs) were undertaken in the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE, PsycINFO, and CINAHL (February 2013). Where insufficient data were presented in a report, attempts were made to contact the original authors for further details.

SELECTION CRITERIA

Studies were considered in which women with a prospective diagnosis of PMS, PMDD or late luteal phase dysphoric disorder (LPDD) were randomised to receive SSRIs or placebo for the treatment of premenstrual syndrome.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed eligible studies for risk of bias, and extracted data on premenstrual symptoms and adverse effects. Studies were pooled using random-effects models. Standardised mean differences (SMDs) with 95% confidence intervals (CIs) were calculated for premenstrual symptom scores, using separate analyses for different types of continuous data (that is end scores and change scores). Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for dichotomous outcomes. Analyses were stratified by type of drug administration (luteal or continuous) and by drug dose (low, medium, or high). We calculated the number of women who would need to be taking a moderate dose of SSRI in order to cause one additional adverse event (number needed to harm: NNH). The overall quality of the evidence for the main findings was assessed using the GRADE working group methods.

MAIN RESULTS

Thirty-one RCTs were included in the review. They compared fluoxetine, paroxetine, sertraline, escitalopram and citalopram versus placebo. SSRIs reduced overall self-rated symptoms significantly more effectively than placebo. The effect size was moderate when studies reporting end scores were pooled (for moderate dose SSRIs: SMD -0.65, 95% CI -0.46 to -0.84, nine studies, 1276 women; moderate heterogeneity (I(2) = 58%), low quality evidence). The effect size was small when studies reporting change scores were pooled (for moderate dose SSRIs: SMD -0.36, 95% CI -0.20 to -0.51, four studies, 657 women; low heterogeneity (I(2)=29%), moderate quality evidence).SSRIs were effective for symptom relief whether taken only in the luteal phase or continuously, with no clear evidence of a difference in effectiveness between these modes of administration. However, few studies directly compared luteal and continuous regimens and more evidence is needed on this question.Withdrawals due to adverse effects were significantly more likely to occur in the SSRI group (moderate dose: OR 2.55, 95% CI 1.84 to 3.53, 15 studies, 2447 women; no heterogeneity (I(2) = 0%), moderate quality evidence). The most common side effects associated with a moderate dose of SSRIs were nausea (NNH = 7), asthenia or decreased energy (NNH = 9), somnolence (NNH = 13), fatigue (NNH = 14), decreased libido (NNH = 14) and sweating (NNH = 14). In secondary analyses, SSRIs were effective for treating specific types of symptoms (that is psychological, physical and functional symptoms, and irritability). Adverse effects were dose-related.The overall quality of the evidence was low to moderate, the main weakness in the included studies being poor reporting of methods. Heterogeneity was low or absent for most outcomes, though (as noted above) there was moderate heterogeneity for one of the primary analyses.

AUTHORS' CONCLUSIONS

SSRIs are effective in reducing the symptoms of PMS, whether taken in the luteal phase only or continuously. Adverse effects are relatively frequent, the most common being nausea and asthenia. Adverse effects are dose-dependent.

Complementary and alternative medications for women's health issues

Women often seek alternative treatment options such as herbs, dietary supplements, and vitamins and minerals to treat women's health issues across the lifespan. Women may use complementary and alternative supplements for dysmenorrhea, premenstrual syndrome, infertility, nausea and vomiting during pregnancy, and symptoms of menopause. In general, there is a deficit of well-designed, randomized, controlled trials to evaluate the efficacy and safety of complementary and alternative medicine for these indications, which makes it difficult to provide evidence-based recommendations. This review outlines the evidence for efficacy and safety that is currently available for dietary supplement use by women to manage health conditions specific to the female patient.