Diet Quality Indexes, Arterial Stiffness and Endothelial Function in Healthy Young Adults

Abstract

Cardiovascular disease (CVD) is the number one cause of death globally. High quality dietary patterns such as the DASH diet and the Mediterranean diet are shown to be effective at improving endothelial function and other vascular risk factors in older adults and those with comorbid conditions. To our knowledge, no study has examined the relation between overall diet quality and vascular function in healthy young adults, which could have implications for preventing CVD onset. We aimed to test the hypothesis that lower diet quality, assessed by diet index scores, would be associated with greater arterial stiffness and poorer endothelial function in healthy, non-hypertensive young adults. Seventeen men and 28 women ages 27.0±0.9 y with normal blood pressure (systolic BP: 112±2 mmHg; diastolic BP: 70±1 mmHg), non-obese body mass index (BMI) (23.4±0.4 kg/m2) and no diagnosed chronic disease completed this cross-sectional study. Two DASH diet scores, the alternative Mediterranean diet score (aMED), and the Healthy Eating Index-2015 (HEI-2015) were calculated from 3-day diet records analyzed with NDSR software. Augmentation index (AIx) and carotid-femoral pulse wave velocity (PWV) were measured using the SphygmoCor XCEL system. Brachial artery flow mediated dilation (FMD) was assessed using ultrasound. Separate multiple linear regression analyses with appropriate physiological variables included in the models (for AIx: height, heart rate, age, and sex; for PWV: mean arterial pressure, BMI, age, and sex; for FMD: age and sex) were used to assess the relation between the dietary indexes and vascular outcomes. Average Mellen DASH score was 2.6±0.2 (out of 9), Fung DASH score was 24.1±0.8 (out of 40), aMED score was 3.9±0.3 (out of 9), and HEI-2015 was 60.8±1.9 (out of 100). Average AIx was 6.4±1.7%, average PWV was 5.5±0.1 m/s, and average FMD was 7.9±2.7%. The Mellen DASH score, the aMED score, and the HEI-2015 were inversely associated with AIx, though the associations did not reach statistical significance (B=-1.416, 95% CI: -3.415, 0.583, p=0.16; B=-1.223, 95% CI: -2.833, 0.388, p=0.133; and B=-0.159, 95% CI: -0.386, 0.069, p=0.167, respectively). No other associations between diet index scores and AIx, PWV, or FMD approached statistical significance. Our results suggest that overall diet quality, as assessed using dietary indexes, is not associated with arterial stiffness or endothelial function in healthy young adults. Notably, however, there was room for improvement in our participants’ diet index scores. Intervention studies are warranted to determine how improving diet quality may affect these vascular outcomes in this population.