A Mediterranean dietary style influences TNF-alpha and VCAM-1 coronary blood levels in unstable angina patients.

BACKGROUND: A Mediterranean dietary pattern has been associated with a reduced risk of coronary heart disease, as well as a reduction of oxidative stress, but studies indicating possible interactions between food intake and inflammatory mediators production at specific sites are lacking. AIM OF THE STUDY: To assess the relationship between Mediterranean diet consumption and inflammatory related molecules production in coronary vessels. METHODS: A previously reported Mediterranean-diet score was computed summing-up the quintiles of eight dietary components from a validated food frequency questionnaire in 24 patients with unstable angina. Tumor necrosis factor (TNF-alpha) and vascular cell adhesion molecule (VCAM-1) concentrations were measured in coronary sinus blood. RESULTS: Both biomarkers showed an inverse association with the Mediterraneandiet score. The association between VCAM-1 and the Mediterranean-diet score had an adjusted beta coefficient of -35.1 ng/ml (95% coefficient interval, CI: -63.5 to -6.7). The adjusted beta coefficient using TNF-alpha as the dependent variable was -41.6 pg/ml (95 % CI: -76.2 to -7.1). The consumption of olive oil as a single item showed a significant inverse association, and a Mediterranean-diet score excluding olive oil was also inversely associated with TNF-alpha and VCAM-1 serum levels in coronary venous blood. CONCLUSIONS: Adherence to a Mediterranean dietary pattern may protect against coronary artery wall production of inflammatory mediators. This finding could provide a novel mechanistic explanation for the recognized lower coronary risk associated with a Mediterranean diet.

Dietary folate and the risk of nonfatal myocardial infarction.

BACKGROUND: Elevated homocysteine levels have been associated with a higher risk of cardiovascular disease. Because folate intake can reduce homocysteine levels, we investigated the association between dietary folate intake and nonfatal myocardial infarction. METHODS: We conducted a case-control study in three tertiary hospitals of Pamplona, Spain, between 1999 and 2001. Study physicians enrolled 171 patients less than 80 years of age with a first nonfatal myocardial infarction and 171 control patients matched by age, sex, hospital and calendar month. We excluded patients with any prior major cardiovascular disease. Participants were interviewed about medical factors and life-style and completed a food frequency questionnaire previously validated in Spain. We calculated energy-adjusted intakes of folate and estimated relative risks (RRs) of myocardial infarction and 95% confidence intervals (CIs) using conditional logistic regression. Relative risks were adjusted for conventional risk factors. RESULTS: Only 6% of participants were taking vitamin supplements. The main sources of folate were green leafy vegetables, green beans, oranges, peppers and lettuces. The estimated matched RR of myocardial infarction for the top three quartiles of folate intake (, above 340 microg/day) was 0.57 (CI = 0.35-0.94), compared with the lowest quartile of intake. The multivariate adjusted RR was 0.51 (CI = 0.24-1.06). There was no apparent dose effect above this threshold. CONCLUSIONS: Our results in a Mediterranean population with natural plant foods as the main source of folate provide further evidence to support the hypothesis that dietary folate intake may be an independent protective factor for myocardial infarction. The magnitude of the effect, its biological plausibility, and the consistency across studies offer support for a causal association.