Garlic intake is an independent predictor of endothelial function in patients with ischemic stroke

Abstract

OBJECTIVES: To investigate the effects of garlic on endothelial function in patients with ischemic stroke (ISS). DESIGN: Cross-sectional study. PARTICIPANTS: 125 Chinese patients with prior ISS due to athero-thrombotic disease were recruited from the outpatient clinics during July 2005 to December 2006. MEASUREMENTS: Daily allium vegetable intake (including garlic, onions, Chinese chives and shallots) was ascertained by means of a validated food frequency questionnaire for Chinese and brachial artery flow-mediated dilatation (FMD) was measured using high-resolution ultrasound in all subjects. RESULTS: The mean age of the study population was 65.9+/-11.1 years and 69% were males. Mean allium vegetable intake and garlic intake of the study population was 7.5+/-12.7g/day and 2.9+/-8.8g/day respectively. Their mean FMD was 2.6+/-2.3%. Daily intake of total allium vegetable (r=0.36, P<0.01) and garlic (r=0.34, P<0.01) significantly correlated with FMD. Using the median daily allium intake as cut-off (3.37g/day), patients with a low allium intake <3.37g/day was noted to have a lower FMD compared to those with a normal allium intake (2.1+/-2.1% versus 3.0+/-2.4%, P<0.05). After adjusting for confounding factors, multi-variate analysis identified that daily allium vegetable (B=0.05, 95% confidence interval: 0.02, 0.09, P<0.01) and garlic (B=0.07, 95% confidence interval: 0.02, 0.12, P<0.01) intake, but not onions, Chinese chives and shallots were independent predictors for changes in FMD in patients with ISS. CONCLUSIONS: Daily garlic intake is an independent predictor of endothelial function in patients with ISS and may play a role in the secondary prevention of atherosclerotic events.