Hypercholesterolemia occurs when there is too much cholesterol in the blood. It is not a disease as such but a metabolic derangement. Elevated cholesterol in the blood is due to an increase in the amount of the so-called lipoproteins, particles that carry cholesterol in the bloodstream. There are two major types of cholesterol: HDL (high-density lipoprotein) cholesterol and LDL (low-density lipoprotein) cholesterol. Hypercholesterolemia usually means elevated levels of total blood cholesterol or LDL-cholesterol with normal or low levels of HDL-cholesterol.
People with hypercholesterolemia have a higher risk of developing coronary artery disease, heart attacks, and stroke. Chinese herbal medicines have been commonly used and studied as cholesterol-lowering agents. To evaluate the effects of various herbal formulations (including single herbs, Chinese proprietary medicines, and mixtures of different herbs) for treating hypercholesterolemia, this review examined 22 randomized controlled trials of five different Chinese herbal medicines. The trials lasted from one to six months (average 2.3 months) and involved 2130 participants. There were no data on cardiovascular events and death from any cause. One trial each reported on well-being (no significant differences) and economic costs . No serious adverse events were observed. The available evidence suggests that several herbal medicines showed some cholesterol-lowering effect. However, due to considerable limitations in the quality of the included trials, further higher-quality and rigorously performed studies are required before any confident conclusions can be reached about the effects of Chinese herbal medicines for hypercholesterolemia.
阅读完整摘要
Hypercholesterolemia is an important key contributory factor for ischemic heart disease and is associated with age, high blood pressure, a family history of hypercholesterolemia, and diabetes. Chinese herbal medicines have been used for a long time as lipid-lowering agents.
研究目的
To assess the effects of Chinese herbal medicines on hypercholesterolemia.
检索策略
We searched the following databases: The Cochrane Library (issue 8, 2010), MEDLINE (until July 2010), EMBASE (until July 2010 ), Chinese BioMedical Database (until July 2010), Traditional Chinese Medical Literature Analysis and Retrieval System (until July 2010), China National Knowledge Infrastructure (until July 2010), Chinese VIP Information (until July 2010), Chinese Academic Conference Papers Database and Chinese Dissertation Database (until July 2010), and Allied and Complementary Medicine Database (until July 2010).
纳入排除标准
We considered randomized controlled clinical trials in hypercholesterolemic participants comparing Chinese herbal medicines with placebo, no treatment, and pharmacological or non-pharmacological interventions.
资料收集与分析
Two review authors independently extracted data and assessed the risk of bias. We resolved any disagreements with this assessment through discussion and a decision was achieved based by consensus. We assessed trials for the risk of bias against key criteria: random sequence generation, allocation concealment, blinding of participants, incomplete outcome data, selective outcome reporting and other sources of bias.
主要结果
We included 22 randomized trials (2130 participants). The mean treatment duration was 2.3 ± 1.3 months (ranging from one to six months). Twenty trials were conducted in China and 18 trials were published in Chinese. Overall, the risk of bias of included trials was high or unclear. Five different herbal medicines were evaluated in the included trials, which compared herbs with conventional medicine in six comparisons (20 trials), or placebo (two trials). There were no outcome data in any of the trials on cardiovascular events and death from any cause. One trial each reported well-being (no significant differences) and economic costs. No serious adverse events were observed. Xuezhikang was the most commonly used herbal formula investigated. A significant effect on total cholesterol (two trial, 254 participants) was shown in favor of Xuezhikang when compared with inositol nicotinate (mean difference (MD) -0.90 mmol/L, 95% confidence interval (CI) -1.13 to -0.68) .
作者结论
Some herbal medicines may have cholesterol-lowering effects. Our findings have to be interpreted with caution due to high or unclear risk of bias of the included trials.
