Background The beneficial role of the Mediterranean diet in cardiovascular diseases (CVD) has been established. However, the biochemical and clinical markers that may be affected favorably by such diet have not been evaluated. The aim of our work was to evaluate the effect of the Mediterranean-type of diet on inflammatory markers, like homocysteine, fibrinogen and C-reactive protein, associated to cardiovascular risk in a cardiovascular disease free sample of general population.
Methods A random algorithm was developed and stratified, by sex - age; multistage sampling was performed, during 2001 - 2002. In this work data from 1128 men (18-87 years old) and 1154 women (18-89 years old) were analysed. The consumption of red meat, chicken, fish, vegetables, legumes, pasta, salads, cereals, dairy products, sweets and fruits was investigated as an average per week, during the past year, using a special nutritional questionnaire, developed by the National School of Public Health. We defined subjects who adopt this type of diet using as cut-off points the median values of the monthly food consumption score. The plasma levels of C-reactive protein, homocysteine and fibrinogen were measured, after 12 hours fast and without any consumption of tea and coffee. Results 24% of men and 36% of women were defined closer to the Mediterranean diet. Data analysis revealed that the adoption of Mediterranean diet is associated with a significant reduction of fibrinogen (312±33 vs. 328±31 mg/dl, P<0.05), homocysteine (12±3 vs. 14±5 mg/dl, P<0.05) and C-reactive protein levels. Next, we classified the participants into quartiles of the investigated parameters. Multivariate analysis revealed that adoption of the Mediterranean diet is associated with 14% lower likelihood of being in the higher quartile of fibrinogen levels (odds ratio = 0.86, p<0.01), 10% lower likelihood of being in the higher quartile of homocysteine levels (odds ratio = 0.90, p<0.01), and 17% lower likelihood of being in the higher quartile of CRP levels (odds ratio = 0.83, p<0.01) as compared with participants in the lower quartiles of the aforementioned factors. Conclusion The "ecological" paradox regarding low CVD mortality in Mediterranean populations, as coined by Keys and his colleagues, is partially explained by the favorable modification of several inflammatory markers.
Christina Chrysohoou, Demosthenes B. Panagiotakos, Christos Pitsavos, Christodoulos Stefanadis, University of Athens, Greece
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