Randomised controlled trial of use by hypercholesterolaemic patients of a vegetable oil sterol-enriched fat spread

Plant sterols may be a useful additive therapy in the treatment of hypercho lesterolaemic patients. The purpose of this study was to determine the effe ct of a fat spread enriched with vegetable oil sterols on plasma lipid, lip oprotein and apolipoprotein concentrations. A randomised double blind place bo-controlled crossover trial with two consecutive periods of 8 weeks was c onducted. 30 patients with heterozygous familial hypercholesterolaemia trea ted concurrently with an HMG-CoA reductase inhibitor (statin) and 32 patien ts with type IIa primary hypercholesterolaemia with a total cholesterol con centration > 6.5 mmol/l not taking lipid-lowering drug therapy were recruit ed from a hospital lipid clinic. The active treatment was a fortified fat s pread (25 g/day) providing 2.5 g of plant sterols. The control spread was i ndistinguishable in taste and appearance. Comparison at the end of the two 8-week trial periods showed a statistically significant reduction in total and LDL-cholesterol with use of the fortified spread but the results were c onfounded by a carry-over effect, which was partly explained by changes in the background diet. Because a carry-over effect was present, further analy ses were restricted to the parallel arms of the first treatment period and were conducted on an intention to treat basis. After 4 weeks, LDL-cholester ol had decreased by 0.04 mmol/l ([0.8%] 95% confidence interval - 0.44-0.37 NS) in the placebo group and decreased by - 0.76 mmol/l ([15.0%] 95% CI - 1.03- - 0.48, P < 0.0001) in the active treatment group. After 8 weeks, the corresponding results were 0.0 mmol/l ([0.0%] 95% CI -0.26-0.24 NS) and - 0.51 mmol/l ([10.0%] 95% CI - 0.73- - 0.29 P < 0.0001). There were no signi ficant changes in apolipoprotein AI or B concentrations in the placebo grou p, but there was a small but statistically significant increase in apolipop rotein AI and a decrease in apolipoprotein B in the active treatment group. HDL cholesterol and triglyceride concentrations were unchanged. There was no difference in response between patients with statin-treated familial hyp ercholesterolaemia and patients with type IIa hyperlipoprotienaemia. We con clude that a fortified fat spread enriched with vegetable oil sterols reduc es LDL-cholesterol by 10-15% with no difference in response between hyperch olesterolaemic patients prescribed statins and those not taking lipid-lower ing drug therapy. (C) 2001 Elsevier Science Ireland Ltd. All rights reserve d.