Chinese herbal medicines for type 2 diabetes mellitus

 

Abstract

Background

Traditional Chinese herbal medicines have been used for a long time to treat diabetes, and many controlled trials have been done to investigate their efficacy.

Objectives

To assess the effects of Chinese herbal medicines in patients with type 2 diabetes mellitus.

Search methods

We searched the following electronic databases: The Cochrane Library (CENTRAL), the Chinese BioMedical Database, MEDLINE, EMBASE, and LILACS, combined with hand searches on Chinese journals and conference proceedings. No language restriction was used.

Selection criteria

Randomised trials of herbal medicines (with at least two months treatment duration) compared with placebo, pharmacological or non-pharmacological interventions were included.

Data collection and analysis

Data were extracted independently by two reviewers. The methodological quality of trials was evaluated using the parameters of randomisation, allocation concealment, double blinding, and drop-out rates. Meta-analyses were performed where data were available.

Main results

Sixty-six randomised trials, involving 8302 participants, met the inclusion criteria. Methodological quality was generally low. Sixty-nine different herbal medicines were tested in the included trials, which compared herbal medicines with placebo, hypoglycaemic drugs, or herbal medicines plus hypoglycaemic drugs.

Compared with placebo, Holy basil leaves, Xianzhen Pian, Qidan Tongmai, traditional Chinese formulae (TCT), Huoxue Jiangtang Pingzhi, and Inolter showed significantly hypoglycaemic response. Compared with hypoglycaemic drugs including glibenclamide, tolbutamide, or gliclazide, seven herbal medicines demonstrated a significant better metabolic control, including Bushen Jiangtang Tang, Composite Trichosanthis, Jiangtang Kang, Ketang Ling, Shenqi Jiangtang Yin, Xiaoke Tang, and Yishen Huoxue Tiaogan. In 29 trials that evaluated herbal medicines combined with hypoglycaemic drugs, 15 different herbal preparations showed additional better effects than hypoglycaemic drugs monotherapy. Two herbal therapies combined with diet and behaviour change showed better hypoglycaemic effects than diet and behaviour change alone. No serious adverse effects from the herbal medicines were reported.

Authors' conclusions

Some herbal medicines show hypoglycaemic effect sin type 2 diabetes. However, these findings should be carefully interpreted due to the low methodological quality, small sample size, and limited number of trials. In the light of some positive findings, some herbal medicines deserve further examination in high-quality trials.

 

Plain language summary

Chinese herbal medicines for type 2 diabetes mellitus

We are still waiting for firm evidence on Chinese herbal medicines for treatment of non-insulin-dependent diabetes. Although the use of herbal medicines for treatment of diabetes has a long history especially in the East, current evidence cannot warrant to support the routine use in clinical practice. This systematic review evaluates the effects of various herbal preparations (including single herbs or mixtures of different herbs) for treating people with type 2 diabetes. The review shows that some herbal medicines lower blood sugar and relieving symptoms in patients with diabetes. However, the methodological quality of the clinical trials evaluating these herbs is generally poor. The analyses also indicate that trials with positive findings are more likely to be associated with exaggerated effects. However, the trials did not report significant adverse effects. In conclusion, herbal medicines should not be recommended for routine use in diabetic patients of type 2 diabetes until we get scientifically sound trials. Testing the herbs in larger, well-designed trials is needed in order to establish the necessary evidence for their use.

 

摘要

背景

治療第2型糖尿病之中藥

傳統的中藥被用於治療第2型糖尿病已有一段很長的時間，且也有許多控制型的臨床試驗探究他們的療效。

目標

評估中藥在治療第2型糖尿病病患的效果。

搜尋策略

我們搜尋以下的電子資料庫: The Cochrane (CENTRAL), the Chinese BioMedical Database, MEDLINE, EMBASE, and LILACS， 並結合手工搜查中文期刊和學術會議公報。最後搜尋的日期是2004年4月。沒有限制使用的語言。

選擇標準

中藥隨機試驗，至少2個月治療期，且有與安慰劑，藥理學或非藥理學介入措施相比。

資料收集與分析

兩位評論者獨立地引用資料。使用隨機化，分配隱藏，雙盲，和中輟率等參數評價試驗所使用的方法學品質。如果相關資料是可獲得的，則作統合分析。

主要結論

66個隨機型試驗(共有8302位受試者)符合收案標準。方法學品質一般而言均低。在收錄的試驗中, 共有69種不同的草藥被測試。這些試驗將受測試的草藥與安慰劑,降血糖藥或草藥與降血糖藥做比較。與安慰劑相比，Holy basil leaves, Xianzhen Pian, Qidan Tongmai, 傳統中藥配方(traditional Chinese formulae, TCT), Huoxue Jiangtang Pingzhi, 及 Inolter顯示出顯著降血糖的反應。與glibenclamide, tolbutamide,或 gliclazide等降血糖藥物相比，包括Bushen Jiangtang Tang, Composite Trichosanthis, Jiangtang Kang, Ketang Ling, Shenqi Jiangtang Yin, Xiaoke Tang, 及 Yishen Huoxue Tiaogan等7種草藥表現出顯著改善的代謝控制。在29個評估草藥結合降血糖藥物的試驗中，15種不同的草藥製劑顯示出比降血糖藥物單一療法有額外更好的效果。兩種結合飲食和行為改變的草藥療法，呈現出比單用飲食和行為改變更好的降血糖作用。所有受測試的草藥均無嚴重的不良作用報告。

作者結論

有些中草藥在2型糖尿病中顯示出降血糖作用。然而，由於方法學品質低，樣本數量小和試驗的數量有限，這些研究發現應該被仔細地解讀。鑑於一些正向的研究發現，某些草藥值得我們在高品質的試驗中作進一步的檢驗。

翻譯人

本摘要由慈濟醫院李哲全翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

我們仍在等待中藥在治療非胰島素依賴型糖尿病上確切的證據。雖然使用草藥治療糖尿病已有悠久的歷史，特別是在東方，然而現有的證據無法保證支持在臨床實務中常規使用。本系統性回顧評估不同的草藥製劑(包括單方或不同中藥的混合物)在治療第2型糖尿病患者上的作用。本回顧顯示，有些中藥可降低血糖和緩解糖尿病患者的症狀。然而，評估這些草藥的臨床試驗的方法學品質普遍都差。本分析也指出，那些有正向發現的試驗更可能與較誇張的作用有關。不管怎樣，這些試驗沒有報告到重大的不良作用。總結來說，直到我們得到更科學性的健全試驗前，草藥不應被建議常規使用在第2型糖尿病患者中。為建立可供使用的必要證據，在較大且精心設計的試驗中測試這些草藥是必要的。