Ingesta de polifenoles y riesgo cardiovascular en el ensayo PREDIMED-Plus. Una comparación de diferentes ecuaciones de riesgo / Polyphenol intake and cardiovascular risk in the PREDIMED-Plus trial. A comparison of different risk equations

Introducción y objetivos: La cuantificación del riesgo cardiovascular se basa en puntuaciones como las de Framingham, Framingham-REGICOR, SCORE o Life's Simple 7 (LS7). Los polifenoles pueden proporcionar beneficios al sistema vascular y reducir la respuesta inflamatoria; sin embargo, los estudios clínico-epidemiológicos muestran resultados discordantes. Nuestro objetivo es evaluar la posible asociación entre la ingesta de diferentes clases de polifenoles y las puntuaciones cardiovasculares. Métodos: Estudio transversal sobre 6.633 participantes del estudio PREDIMED-Plus. El contenido de polifenoles se estimó mediante un cuestionario semicuantitativo de frecuencia alimentaria y se ajustó por la ingesta energética total según el método de residuales. La asociación entre la ingesta de polifenoles y el riesgo cardiovascular se evaluó mediante análisis de regresión lineal. Resultados: La ingesta total de polifenoles y flavonoides se asoció directa y significativamente con la escala LS7. Igualmente, los lignanos se asociaron directa y significativamente con las escalas SCORE y LS7; los estilbenos, con la SCORE y los ácidos fenólicos, con las de Framingham y Framingham-REGICOR. La clase «otros polifenoles» se asoció de manera significativa con las escalas de Framingham, SCORE y LS7. En las mujeres, la ingesta de todas las clases de polifenoles, excepto los ácidos fenólicos, mostró una tendencia directa en los resultados de Framingham y Framingham-REGICOR e indirecta con la escala LS7. Conclusiones: Se encontraron asociaciones inversas entre el consumo de la clase «otros polifenoles» y, especialmente en las mujeres, el riesgo cardiovascular estimado. Los resultados fueron similares con las de Framingham, Framingham-REGICOR y LS7 (después de eliminar el componente de dieta) y diferentes con la SCORE, pero los predictores que se incluyen en este son escasos (AU)

Introduction and objectives: Quantification of cardiovascular risk has been based on scores such as Framingham, Framingham-REGICOR, SCORE or Life's Simple 7 (LS7). In vitro, animal, and randomized clinical studies have shown that polyphenols may provide benefits to the vascular system and reduce the inflammatory response. However, some clinical-epidemiological studies have yielded inconsistent results. Our aim was to assess the possible association between intake of the various polyphenol classes and established cardiovascular scores. Methods: This cross-sectional analysis involved 6633 PREDIMED-Plus study participants. Food polyphenol content was estimated by a semiquantitative food frequency questionnaire, adjusted for total energy intake according to the residual method. The association between polyphenol intake and cardiovascular risk was tested using linear regression analyses. Results: Total polyphenol and flavonoid intake were directly and significantly associated only with the LS7 scale. Intake of lignans was directly and significantly associated with SCORE and LS7 scales, stilbene intake with SCORE, and phenolic acid intake with Framingham and Framingham-REGICOR scores. Other polyphenol classes were associated in a protective and significant manner in Framingham, SCORE and LS7 scores. In women, intake of all the polyphenol classes, except phenolic acids, showed a protective trend in the results of the Framingham, Framingham-REGICOR scores and LS7 scale. Conclusions: An inverse association was found between consumption of the ‘other polyphenols’ class and, especially among women, with estimated cardiovascular risk. The results were similar to those of Framingham, Framingham-REGICOR and LS7 (after eliminating the diet component) and differed from those of SCORE, but the predictors included were limited in the latter case (AU)

Dietary total antioxidant capacity and mortality in the PREDIMED study.

PURPOSE: The aim of the present study was to assess the association between the dietary total antioxidant capacity, the dietary intake of different antioxidants and mortality in a Mediterranean population at high cardiovascular disease risk. METHODS: A total of 7,447 subjects from the PREDIMED study (multicenter, parallel group, randomized controlled clinical trial), were analyzed treating data as an observational cohort. Different antioxidant vitamin intake and total dietary antioxidant capacity were calculated from a validated 137-item food frequency questionnaire at baseline and updated yearly. Deaths were ascertained through contact with families and general practitioners, review of medical records and consultation of the National Death Index. Cox regression models were fitted to assess the relationship between dietary total antioxidant capacity and mortality. Dietary total antioxidant capacity was estimated using ferric-reducing antioxidant power assays. RESULTS: A total of 319 deaths were recorded after a median follow-up of 4.3 years. Subjects belonging to the upper quintile of antioxidant capacity were younger, ex-smokers, with high educational level, and more active and had higher alcohol intake. Multivariable-adjusted models revealed no statistically significant difference between total dietary antioxidant capacity and mortality (Q5 vs. Q1 ref HR 0.85; 95% CI 0.60-1.20) neither for the intake of all the vitamins studied. CONCLUSIONS: No statistically significant association was found between antioxidant capacity and total mortality in elderly subjects at high cardiovascular risk.

Effects of total dietary polyphenols on plasma nitric oxide and blood pressure in a high cardiovascular risk cohort. The PREDIMED randomized trial.

BACKGROUND AND AIM: Hypertension is one of the main cardiovascular risk factors in the elderly. The aims of this work were to evaluate if a one-year intervention with two Mediterranean diets (Med-diet) could decrease blood pressure (BP) due to a high polyphenol consumption, and if the decrease in BP was mediated by plasma nitric oxide (NO) production. METHODS AND RESULTS: An intervention substudy of 200 participants at high cardiovascular risk was carried out within the PREDIMED trial. They were randomly assigned to a low-fat control diet or to two Med-diets, one supplemented with extra virgin olive oil (Med-EVOO) and the other with nuts (Med-nuts). Anthropometrics and clinical parameters were measured at baseline and after one year of intervention, as well as BP, plasma NO and total polyphenol excretion (TPE) in urine samples. Systolic and diastolic BP decreased significantly after a one-year dietary intervention with Med-EVOO and Med-nuts. These changes were associated with a significant increase in TPE and plasma NO. Additionally, a significant positive correlation was observed between changes in urinary TPE, a biomarker of TP intake, and in plasma NO (Beta = 4.84; 95% CI: 0.57-9.10). CONCLUSIONS: TPE in spot urine sample was positively correlated with plasma NO in Med-diets supplemented with either EVOO or nuts. The statistically significant increases in plasma NO were associated with a reduction in systolic and diastolic BP levels, adding to the growing evidence that polyphenols might protect the cardiovascular system by improving the endothelial function and enhancing endothelial synthesis of NO.

Inverse association between habitual polyphenol intake and incidence of cardiovascular events in the PREDIMED study.

BACKGROUND AND AIMS: Epidemiologic and biological evidence supports an inverse association between polyphenol consumption and the risk of cardiovascular disease (CVD). However, no previous studies have prospectively evaluated the relationship between polyphenol intake and the incidence of CVD in such a comprehensive way. The aim was to evaluate the association between intakes of total polyphenol and polyphenol subgroups, and the risk of major cardiovascular events (myocardial infarction, stroke or death from cardiovascular causes) in the PREDIMED study. METHODS AND RESULTS: The present work is an observational study within the PREDIMED trial. Over an average of 4.3 years of follow-up, there were 273 confirmed cases of CVD among the 7172 participants (96.3%) who completed a validated 137-item food frequency questionnaire (FFQ) at baseline. Polyphenol consumption was calculated by matching food consumption data from the FFQ with the Phenol-Explorer database on polyphenol content of each reported food. After multivariate adjustment, a 46% reduction in risk of CVD risk was observed comparing Q5 vs. Q1 of total polyphenol intake (HR = 0.54; 95% confidence interval [CI] = 0.33-0.91; P-trend = 0.04). The polyphenols with the strongest inverse associations were flavanols (HR = 0.40; CI 0.23-0.72; P-trend = 0.003), lignans (HR = 0.51; CI 0.30-0.86; P-trend = 0.007), and hydroxybenzoic acids (HR = 0.47; CI 0.26-0.86; P-trend 0.02). CONCLUSION: Greater intake of polyphenols, especially from lignans, flavanols, and hydroxybenzoic acids, was associated with decreased CVD risk. Clinical trials are needed to confirm this effect and establish accurate dietary recommendations.

Dietary intake and major food sources of polyphenols in a Spanish population at high cardiovascular risk: the PREDIMED study.

BACKGROUND AND AIMS: Epidemiological data have shown an inverse association between the consumption of polyphenol-rich foods and the risk of cardiovascular disease or overall mortality. A comprehensive estimation of individual polyphenol intake in nutritional cohorts is needed to gain a better understanding of this association. The aim of this study was to estimate the quantitative intake of polyphenols and the major dietary sources in the PREDIMED (PREvención con DIeta MEDiterránea) cohort using individual food consumption records. METHODS AND RESULTS: The PREDIMED study is a large, parallel-group, multicentre, randomised, controlled 5-year feeding trial aimed at assessing the effects of the Mediterranean diet on the primary prevention of cardiovascular disease. A total of 7200 participants, aged 55-80 years, completed a validated 1-year food frequency questionnaire (FFQ) at baseline. Polyphenol consumption was calculated by matching food consumption data from the FFQ with the recently developed Phenol-Explorer database on polyphenol content in foods. The mean total polyphenol intake was 820 ± 323 mg day⁻¹ (443 ± 218 mg day⁻¹ of flavonoids and 304 ± 156 mg day⁻¹ of phenolic acids). Hydroxycinnamic acids were the phenolic group with the highest consumption and 5-caffeoylquinic acid was the most abundantly ingested individual polyphenol. The consumption of olives and olive oil was a differentiating factor in the phenolic profile of this Spanish population compared with other countries. CONCLUSION: In Mediterranean countries, such as Spain, the main dietary source of polyphenols is coffee and fruits, but the most important differentiating factor with respect to other countries is the consumption of polyphenols from olives and olive oil.