Erxian decoction, a Chinese herbal formula, for menopausal syndrome: An updated systematic review

Erxian decoction (EXD), a famous Chinese herbal prescription, consists of Rhizoma Curculiginis, Herba Epimedii, Radix Morindae Officinalis, Radix Angelicae Sinensis, Cortex Phellodendri, Rhizoma Anemarrhenae, all of which are recorded in the Chinese Pharmacopoeia.

To conduct an updated systematic and meta-analysis investigating efficacy and safety of EXD for menopausal syndrome.

An electronic search was conducted in eight databases from inception until July 2018. Randomized controlled trials with risk-of-bias score ≥ 7 according to the Cochrane Back Review Group were included for analyses. All participants with a diagnosis of menopausal syndrome met the established criteria. The treatment group was EXD monotherapy or adjunct therapy. Comparators were placebo, hormone replace therapy, hormone plus nonhormonal agents, nonhormonal agents and no treatment. The primary outcome measurements were the Kupperman index, total hot flush scores, total menopause rating scale (MRS) scores and total menopause-specific quality of life (MENQOL) scores. The secondary outcomes were total clinical effective rate, traditional Chinese medicine (TCM) syndrome scores, Hamilton depression (HAMD) scale scores, self-rating depression scale (SDS) scores, self-Rating Anxiety Scale (SAS) scores, athens insomnia scale (AIS) scores, serological indicators, blood pressure, and adverse events. RevMan 5.3 Software was used for data analyses. GRADE system was used to assess the level of evidence.

Sixteen eligible studies with 1594 subjects were identified. Five studies showed EXD was contradictory results according to Kupperman index of menopausal syndrome compared with hormone. One study showed EXD significantly improved total hot flush scores, total MRS scores and total MENQOL scores compared with placebo (P < 0.05). Meta-analysis of 10 EXD monotherapy or 2 paratherapy studies showed that both can significantly improve total effective rate compared with hormone (P < 0.05); 3 studies showed that EXD plus hormone significantly reduces the TCM syndrome scores, HAMD scale scores, SDS scores and SAS scores compared with hormone (P < 0.05). One study showed a significant effect of EXD for reducing AIS scores compared with hormone (P < 0.05); 7 studies showed contradictory effects for improving serological indicators compared with hormone. Two studies reported adverse effects, whereas the other studies did not mention. The quality of the evidence of primary outcomes was moderate to high according to the GRADE profiler.

The present findings do not allow an assessment of the evidence because the low-quality studies included cannot be reproduced. However, we identified an area, which is worthy of further research. Rigorous RCTs are still needed in the future.