Effects of Polyphenol, Measured by a Biomarker of Total Polyphenols in Urine, on Cardiovascular Risk Factors After a Long-Term Follow-Up in the PREDIMED Study

Abstract

Several epidemiological studies have shown an inverse association between the consumption of polyphenol-rich foods and risk of cardiovascular diseases. However, accuracy and reliability of these studies may be increased using urinary total polyphenol excretion (TPE) as a biomarker for total polyphenol intake. Our aim was to assess if antioxidant activity, measured by a Folin-Ciocalteu assay in urine, is correlated with an improvement in cardiovascular risk factors (blood pressure and serum glucose, cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride concentrations) in an elderly population at high risk. A longitudinal study was performed with 573 participants (aged 67.3 ± 5.9) from the PREDIMED study (ISRCTN35739639). We used Folin-Ciocalteu method to determine TPE in urine samples, assisting with solid phase extraction. Participants were categorized into three groups according to changes in TPE. Multiple linear regression models were used to assess relationships between TPE and clinical cardiovascular risk factors, adjusting for potential confounders. After a 5-year follow-up, significant inverse correlations were observed between changes in TPE and plasma triglyceride concentration (β = −8.563; P = 0.007), glucose concentration (β = −4.164; P = 0.036), and diastolic blood pressure (β = −1.316; P = 0.013). Our results suggest that the consumption of more polyphenols, measured as TPE in urine, could exert a protective effect against some cardiovascular risk factors.

Effect of dietary polyphenols on cardiovascular risk

“…This finding is in agreement with previous reports describing the vasodilator effects of phenolic compounds 5 6. In experimental studies, dietary polyphenols have been shown to stimulate the secretion of endothelial nitric oxide (NO), potentially decreasing blood pressure.…”

Recommended Dietary Pattern to Achieve Adherence to the American Heart Association/American College of Cardiology (AHA/ACC) Guidelines: A Scientific Statement From the American Heart Association

“…A subsequent longitudinal study also reported higher polyphenol intake associated with this diet based on dietary and urinary measures that was associated with reductions in plasma glucose and triglycerides and lower BP. 30 In summary, greater adherence to the Mediterranean dietary pattern has been associated with reductions in coronary heart disease risk by 29% to 69% and reduced risk of a stroke by 13% to 53%. Data from recent metaanalyses reported a 10% reduction in risk of CVD (fatal or nonfatal clinical CVD event) per 2-increment increase in adherence to the Mediterranean-style diet.…”

Coffee Consumption and Coronary Artery Calcium Score: Cross‐Sectional Results of ELSA‐Brasil (Brazilian Longitudinal Study of Adult Health)

“…Despite the fact that acute coffee consumption might increase blood pressure, this effect seems to disappear with long‐term coffee consumption, and large prospective studies do not support the hypothesis that high coffee consumption increases the risk of hypertension . Coffee is a beverage with very complex chemical composition, rich in phenolic compounds, predominantly hydroxycinnamic acids, which demonstrate protective roles in the cardiovascular system . This cardiovascular protection has been confirmed in vivo and can be explained by various mechanisms, including their anti‐inflammatory properties, strong antioxidant activity that might prevent low‐density lipoprotein oxidation, and antithrombotic capacities associated with improved endothelial function and nitric oxide bioavailability, protecting against thrombus formation or atherosclerotic lesion development.…”

“…Lifestyle and dietary factors, such as a lack of physical activity, excess body weight, smoking, excessive alcohol intake, and unhealthy diet, are implicated in the etiology of CVD . Coffee is one of the most popular and widely consumed nonalcoholic beverages in the world, and its role in CVD is still being debated and remains controversial .…”