Horse chestnut seed extract for chronic venous insufficiency.

BACKGROUND: Conservative therapy of chronic venous insufficiency (CVI) consists largely of compression treatment. However, this often causes discomfort and has been associated with poor compliance. Therefore, oral drug treatment is an attractive option.

OBJECTIVES: To review the efficacy and safety of oral horse chestnut seed extract (HCSE) versus placebo, or reference therapy, for the treatment of CVI.

SEARCH STRATEGY: We searched the Cochrane Peripheral Vascular Diseases Review Group's Specialised Register (October 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library Issue 3, 2005, MEDLINE (January 1966 to October 2005), EMBASE (January 1980 to October 2005), Allied and Complementary Medicine (AMED) (inception to July 2005) and Phytobase (inception to January 2001) for randomised controlled trials (RCTs) of HCSE for chronic venous insufficiency. Manufacturers of HCSE preparations and experts on the subject were contacted for published and unpublished material. There were no restrictions on language.

SELECTION CRITERIA: RCTs were included if they compared oral HCSE mono-preparations with placebo, or reference therapy, in people with CVI. Trials assessing HCSE as one of several active components in a combination preparation, or as a part of a combination treatment, were excluded.

DATA COLLECTION AND ANALYSIS: Both authors independently selected the studies and, using a standard scoring system, assessed methodological quality and extracted data. Disagreements concerning evaluation of individual trials were resolved through discussion.

MAIN RESULTS: Overall, there appeared to be an improvement in CVI related signs and symptoms with HCSE compared with placebo. Leg pain was assessed in seven placebo-controlled trials. Six reported a significant reduction of leg pain in the HCSE groups compared with the placebo groups, while another reported a statistically significant improvement compared with baseline. One trial suggested a weighted mean difference (WMD) of 42.4 mm (95% confidence interval (CI) 34.9 to 49.9) measured on a 100 mm visual analogue scale. Leg volume was assessed in seven placebo-controlled trials. Meta-analysis of six trials (n = 502) suggested a WMD of 32.1ml (95% CI 13.49 to 50.72) in favour of HCSE compared with placebo. One trial indicated that HCSE may be as effective as treatment with compression stockings. Adverse events were usually mild and infrequent.

AUTHORS' CONCLUSIONS: The evidence presented implies that HCSE is an efficacious and safe short-term treatment for CVI. However, several caveats exist and more rigorous RCTs are required to confirm the efficacy of this treatment option.