Lactotripeptides intake and blood pressure management: A meta-analysis of randomised controlled clinical trials

Background and aimsLactotripeptides (LTPs, including IPP and VPP) have held promise in the framework of lifestyle modification for prevention and control of hypertension – a cardiovascular risk factor, as LTPs are reported to have an inhibitory effect on angiotensin-converting enzyme. While the number of clinical trials to test the efficacy of LTP continues to increase, the results have been inconsistent, especially in the last few years. The purpose of the present meta-analysis is to precisely estimate the pooled mean effect of LTPs on conventional blood pressure (BP) generally and on 24-h ambulatory BP (ABP) particularly, as well as the change of BP in relation to baseline BP, race, and study design, to better reflect the evolving field.Data synthesisIn general analysis of 24 studies with 28 trials on 1919 human subjects, there are small reductions in both systolic BP (SBP) and diastolic BP (DBP) with the pooled mean effects of 1.66 (95% confidence interval (CI): −2.48 and −0.84) and 0.76 mmHg (−1.31 and −0.20) in response to LTP administration. In analysis of 24-h ABP response to LTP intervention, the reductions of SBP and DBP are 1.30 (−2.49 and −0.11) and 0.57 mmHg (−1.49 and 0.35). In subgroup analysis, the anti-hypertensive efficacy appears to be related to baseline BP, ethnic differences, treatment duration and double versus not double-blind design.ConclusionsThe present findings indicate that the BP-lowering effect of LTP is statistically significant, though small in magnitude. More clinical investigations (especially randomized double-blind trials with ABP) are warranted to determine the anti-hypertensive efficacy of LTP conclusively.