Longer-term effects of the egg-protein hydrolysate NWT-03 on arterial stiffness and cardiometabolic risk markers in adults with metabolic syndrome: a randomized, double-blind, placebo-controlled, crossover trial

Background Short-term intake of egg-derived protein hydrolysates, such as NWT-03, suggest improvements in arterial stiffness and metabolic profiles, but longer-term trials are lacking. This study therefore examined the longer-term effects of NWT-03 on arterial stiffness and cardiometabolic markers in men and women with metabolic syndrome. Methods Seventy-six adults with metabolic syndrome (age 61 ± 10 years; BMI 31.7 ± 4.0 kg/m 2 ) participated in a randomized, controlled, double-blind, cross-over trial with a 27-day intervention (5 g/day NWT-03) or placebo period, separated by two-to-eight weeks of washout. At the start and end of both periods, measurements were performed in the fasting state and 2 h following acute NWT-03 intake. Arterial stiffness was assessed by carotid-to-radial (PWV c-r ), carotid-to-femoral pulse wave velocity (PWV c-f ), and central augmentation index (CAIxHR75). Moreover, cardiometabolic markers were assessed. Results Compared with control, longer-term NWT-03 supplementation did not affect fasting PWV c-r (0.1 m/s; −0.2 to 0.3; P = 0.715) or PWV c-f (−0.2 m/s; −0.5 to 0.1; P = 0.216). Fasting pulse pressure (PP) was however reduced by 2 mmHg (95% CI: −4 to 0; P = 0.043), but other fasting cardiometabolic markers were not affected. No effects were observed following acute NWT-03 intake at baseline. However, acute intake of NWT-03 after the intervention significantly lowered CAIxHR75 (−1.3%-point; −2.6 to −0.1; P = 0.037) and diastolic BP (−2 mmHg; −3 to 0; P = 0.036), but other cardiometabolic markers did not change. Conclusion Longer-term NWT-03 supplementation did not affect arterial stiffness, but modestly improved fasting PP in adults with metabolic syndrome. Acute intake of NWT-03 after the intervention also improved CAIxHR75 and diastolic BP. Trial registration The study was registered at ClinicalTrials.gov as NCT02561663.