Cochrane Database Syst Rev. 2002 ; (4): CD002785.

Chelation therapy for atherosclerotic cardiovascular disease.

Villarruz MV, Dans A, Tan F.

4050 - G Bigasan Street, Palanan 1235, Makati City, Philippines. essie@vasia.com

BACKGROUND: Chelation therapy is being promoted and practiced all over the world as a form of alternative medicine in the treatment of atherosclerotic cardiovascular disease. It has been recommended as a safe, relatively inexpensive and non-surgical method of restoring blood flow in atherosclerotic vessels. At present the benefit of chelation therapy remains controversial at best. OBJECTIVES: The objective of this review is to assess the effects of ethylene diamine tetraacetic acid (EDTA) chelation therapy on clinical outcomes among patients with atherosclerotic cardiovascular disease. SEARCH STRATEGY: The reviewers searched the Cochrane Peripheral Vascular Diseases Group Trials Register, (last searched July 2002), the Cochrane Controlled Trials Register, (Cochrane Library Issue 2, 2002), MEDLINE and EMBASE for published articles and other relevant articles. Studies were also requested through correspondence with known Filipino practitioners of the procedure. SELECTION CRITERIA: Studies were included if they were randomized controlled trials of EDTA chelation therapy versus placebo or no treatment in patients with atherosclerotic cardiovascular disease. Main outcome measures considered included either total or cause-specific mortality, non-fatal cardiovascular events, direct or indirect measurement of disease severity, subjective measures of improvement or adverse events. DATA COLLECTION AND ANALYSIS: Two reviewers (MVV, FT) extracted data and assessed trial quality independently. Unresolved issues were considered by a third reviewer (ALD). Discrepancies were discussed until a consensus was reached. Authors were contacted for additional information. MAIN RESULTS: A total of five studies was included in the review. Mortality, non-fatal events, and cerebrovascular events were not reported in any of the studies. Four of the studies, with a total recruitment rate of 250 participants, showed no significant difference in the following outcomes: direct or indirect measurement of disease severity and subjective measures of improvement. One of the studies, which included only 10 patients, was interrupted prematurely, because of an apparent treatment effect. However, relevant data were not available in the report and have been requested from the authors. REVIEWER'S CONCLUSIONS: At present, there is insufficient evidence to decide on the effectiveness or ineffectiveness of chelation therapy in improving clinical outcomes of patients with atherosclerotic cardiovascular disease. This decision must be preceded by conducting randomized controlled trials that would include endpoints that show the effects of chelation therapy on longevity and quality of life among patients with atherosclerotic cardiovascular disease.