The effect of oat -glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for CVD risk reduction: a systematic review and meta-analysis of randomised-controlled trials

Oats are a rich source of -glucan, a viscous, soluble fibre recognised for its cholesterol-lowering properties, and are associated with reduced risk of CVD. Our objective was to conduct a systematic review and meta-analysis of randomised-controlled trials (RCT) investigating the cholesterol-lowering potential of oat -glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for the risk reduction of CVD. MEDLINE, Embase, CINAHL and Cochrane CENTRAL were searched. We included RCT of 3 weeks of follow-up, assessing the effect of diets enriched with oat -glucan compared with controlled diets on LDL-cholesterol, non-HDL-cholesterol or apoB. Two independent reviewers extracted data and assessed study quality and risk of bias. Data were pooled using the generic inverse-variance method with random effects models and expressed as mean differences with 95 % CI. Heterogeneity was assessed by the Cochran's Q statistic and quantified by the I-2-statistic. In total, fifty-eight trials (n 3974) were included. A median dose of 35 g/d of oat -glucan significantly lowered LDL-cholesterol (-019; 95 % CI -023, -014 mmol/l, P < 000001), non-HDL-cholesterol (-020; 95 % CI -026, -015 mmol/l, P < 000001) and apoB (-003; 95 % CI -005, -002 g/l, P < 00001) compared with control interventions. There was evidence for considerable unexplained heterogeneity in the analysis of LDL-cholesterol (I-2=79 %) and non-HDL-cholesterol (I-2=99 %). Pooled analyses showed that oat -glucan has a lowering effect on LDL-cholesterol, non-HDL-cholesterol and apoB. Inclusion of oat-containing foods may be a strategy for achieving targets in CVD reduction.