Total polyphenol excretion and blood pressure in subjects at high cardiovascular risk

Received 20 July 2009; received in revised form 22 October 2009; accepted 23 October 2009. published online 18 February 2010.
Corrected Proof

Abstract

Background and aims

Dietary factors are critical for the prevention and treatment of hypertension, but data on the effects of specific nutrients on blood pressure (BP) are scarce. The aim of this study was to assess the relationship between total polyphenol excretion (TPE) in urine, as an objective measurement of total polyphenol intake and BP in an elderly population at high cardiovascular risk.

Methods and results

Cross-sectional substudy of 589 high-risk participants entering in the PREDIMED trial. BP was measured and TPE was determined in urine by Folin–Ciocalteu assay. A significant positive association was observed between TPE in urine and daily intake of fruit and vegetables (F&V), coffee or wine after adjusting for potential confounders. The intake of 100g of F&V (Beta=0.150;P<0.001) had a greater contribution to TPE than 100mL of coffee (Beta=0.141;P=0.001), and the latter two foods contributed more than the consumption of 100mL of wine (Beta=0.120;P=0.019). An inverse association was observed between urinary TPE and the prevalence of hypertension. Participants in the highest quartile of urinary TPE had a reduced prevalence of hypertension compared to those in the lowest quartile (Odds Ratio=0.64; 95% confidence interval 0.45 to 0.92; P=0.015). Systolic and diastolic BP were inversely associated with urinary TPE after adjustment for potential confounders (P=0.024 and P=0.003, respectively).

Conclusions

Polyphenol intake, assessed via TPE in urine, was negatively associated with BP levels and prevalence of hypertension in an elderly Mediterranean population at high cardiovascular risk. Participants with the highest intake of polyphenol-rich foods showed the lowest BP measurements.

Keywords: Polyphenol, Urinary polyphenol, Folin–Ciocalteu, Fruits, Vegetables, Coffee, Wine, Hypertension, Blood pressure, Mediterranean diet, Biomarker

a Nutrition and Food Science Department, XaRTA, INSA, Pharmacy School, University of Barcelona, Barcelona, Spain

b CIBER CB06/03 Fisiopatología de la Obesidad y la Nutrición, (CIBEROBN), Spain

c RETICS RD06/0045, Instituto de Salud Carlos III, Spain

d Ingenio-CONSOLIDER Program, FUN-C-FOOD, Barcelona, Spain

e Department of Preventive Medicine and Public Health, School of Medicine, University of Navarra, Pamplona, Spain

f Cardiovascular Epidemiology Unit, Municipal Institute for Medical Research (IMIM), Barcelona, Spain

g Department of Epidemiology, Preventive Medicine and Public Health, School of Medicine, University of Valencia, Valencia, Spain

h Human Nutrition Unit, School of Medicine, IISPV, University Rovira i Virgili, Reus, Spain

i Department of Epidemiology, School of Medicine, University of Malaga, Málaga, Spain

j Instituto de la Grasa, Consejo Superior de Investigaciones Cientificas, Sevilla, Spain

k Department of Family Medicine, Primary Care Division of Sevilla, San Pablo Health Center, Sevilla, Spain

l Institut Universitari d’Investigació en Ciències de la Salut (IUNICS), Palma de Mallorca, Spain

m Clinical Trials Unit, Hospital Txangorritxu, Vitoria, Spain

n Department of Biochemistry and Molecular Biology Service of Clinical Analysis, CDB Hospital General Universitario, Universitat de Valencia, Spain

o Lipid Clinic, Endocrinology and Nutrition Service, Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Hospital Clinic, Barcelona, Spain

p Department of Clinical Sciences, University of Las Palmas de Gran Canaria, Palmas de Gran Canaria, Spain

q Lipid Unit, Department of Internal Medicine, IDIBELL-Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Fipec, Barcelona, Spain

r Immunonutrition Research Group, Instituto del Frío-ICTAN (CSIC), Madrid, Spain

s Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden

t Department of Internal Medicine, Hospital Clinic, IDIBAPS, University of Barcelona, Spain

Corresponding author. Nutrition and Food Science Department, XaRTA, INSA Pharmacy School, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain. Tel.: +34 934034843; fax: +34 934035931.

PII: S0939-4753(09)00278-6

doi:10.1016/j.numecd.2009.10.019