Die Bedeutung von Folsäure für die Gesundheit in verschiedenen Lebensphasen - Teil 2: Folsäure und kardiovaskuläre Erkrankungen

Zusammenfassung

Neben der Fehlbildungsprävention durch das wasserlösliche Vitamin Folsäure wurde in den vergangenen Jahren die Assoziation von Folsäure mit kardiovaskulären Erkrankungen untersucht. Genaue Mechanismen der kardioprotektiven Wirkung von Folsäure sind bislang unklar. In zahlreichen Studien wurde die Beeinflussung eines erhöhten Homocysteinspiegels, der als Risikofaktor für Herz-Kreislauf-Erkrankungen gilt, durch Folsäure untersucht. Folsäure ist hierbei in der Lage, die Konzentrationen von Homocystein im Plasma zu senken. Allerdings ergaben die Untersuchungen zum Teil kontroverse Ergebnisse, so dass noch nicht eindeutig geklärt ist, ob erhöhte Homocysteinkonzentrationen an der Pathogenese der Atherosklerose beteiligt sind oder einen indirekten Risikomarker für kardiovaskuläre Erkrankungen darstellen, wie zum Beispiel für einen Folsäuremangel. Die Bedeutung der Folsäuresupplementation in der Sekundärprävention ist ebenfalls noch nicht eindeutig geklärt, da bisher keine Ergebnisse aus klinischen Interventionsstudien vorliegen.

Summary

Apart from the prevention of congenital malformations by supple- mentation of folic acid, the association of folate intake and cardiovascular diseases has been studied. In fact, exact mechanisms causing the cardioprotective effects of folate supplementation have not been adequately investigated. However, a large number of relative studies could prove the influence of folate on the homocysteine concentration of plasma which is considered a risk factor for cardiovascular diseases. It was discovered that folic acid can lower the homocysteine concentration. These investigations have in part led to contrasting results. It was, for instance, not possible to find out whether an increased homocysteine concentration contributes to the pathogenesis of atherosclerosis or whether it denotes an indirect risk factor for cardiovascular diseases such as a folic-acid deficiency. Neither has the impact of folic acid supplementation as a secondary prophylactic treatment been definitely cleared since results of intervention studies are still lacking.

Schlüsselwörter

Folsäure - Herz-Kreislauf-Erkrankungen - Anreicherung - Mortalität

Key words

Folic acid - folate - homocysteine - cardiovascular diseases - food fortification

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