Effect of fermented milk product containing lactotripeptides and plant sterol esters on haemodynamics in subjects with the metabolic syndrome--a randomised, double-blind, placebo-controlled study.

We investigated the effects of fermented milk product containing isoleucine-proline-proline, valine-proline-proline and plant sterol esters (Pse) on plasma lipids, blood pressure (BP) and its determinants systemic vascular resistance and cardiac output. In a randomised, double-blind, placebo-controlled study, 104 subjects with the metabolic syndrome (MetS) were allocated to three groups in order to receive fermented milk product containing (1) 5 mg/d lactotripeptides (LTP) and 2 g/d plant sterols; (2) 25 mg/d LTP and 2g/d plant sterols; (3) placebo for 12 weeks. Plasma lipids and home BP were monitored. Haemodynamics were examined in a laboratory using radial pulse wave analysis and whole-body impedance cardiography in the supine position and during orthostatic challenge. There were no differences between the effects of the two treatments and placebo on the measurements of BP at home or on BP, systemic vascular resistance index and cardiac index in the laboratory, neither in the supine nor in the upright position. The changes in plasma LDL-cholesterol concentration were -0.1 (95% CI -0.3, 0.1 and -0.3, 0.0) mmol/l in the 5 and 25 mg/d LTP groups, respectively, and +0.1 (95% CI -0.1, 0.3) mmol/l during placebo (P=0.024). Both at baseline and at week 12, the increase in systemic vascular resistance during head-up tilt was lower in the 25 mg/d LTP group than in the 5 mg/d LTP group (P<0.01), showing persistent differences in cardiovascular regulation between these groups. In subjects with the MetS, intake of LTP and Pse in fermented milk product showed a lipid-lowering effect of borderline significance, while no antihypertensive effect was observed at home or in the laboratory.