Hyperhomocysteinämie und B-Vitaminmangel bei neurologischen und psychiatrischen Erkrankungen

W. Herrmann; S. Lorenzl; R. Obeid

doi:10.1055/s-2007-980112

Fortschritte der Neurologie · Psychiatrie, Table of Contents

Fortschr Neurol Psychiatr 2007; 75(9): e1-e18
DOI: 10.1055/s-2007-980112

Übersicht

Hyperhomocysteinämie und B-Vitaminmangel bei neurologischen und psychiatrischen Erkrankungen

Aktueller Kenntnisstand und vorläufige EmpfehlungenReview of the Role of Hyperhomocysteinemia and B-Vitamin Deficiency in Neurological and Psychiatric DisordersCurrent Evidence and Preliminary RecommendationsW. Herrmann¹ , S. Lorenzl² , R. Obeid¹

¹Institut für Klinische Chemie und Laboratoriumsmedizin, Universitätsklinikum des Saarlandes, Homburg
²Neurologische Klinik, Interdisziplinäres Zentrum für Palliativmedizin, Klinikum Großhadern, München

Abstract

Zusammenfassung

Hyperhomocysteinämie (HHcy) (Plasmakonzentration > 12 µmol/l) ist in vielen Studien mit Erkrankungen des zentralen Nervensystems in Verbindung gebracht worden. Mehrere epidemiologische Studien zeigen eine positive, dosisabhängige Beziehung zwischen dem Homocysteinspiegel (Hcy) und dem Risiko neurodegenerative Erkrankungen zu entwickeln. Hcy ist ein Marker für B-Vitaminmangel (Folat, B₁₂, B₆). Die Verminderung des Risikos für die Entwicklung von neurodegenerativen wie psychiatrischen Erkrankungen durch eine Hcy-Senkung mit B-Vitaminen ist in vielen aber nicht allen Studien gezeigt worden. Jüngste Studien und eine Metaanalyse belegen, dass eine Hcy-senkende Behandlung mit B-Vitaminen in der Primär- und Sekundärprävention von Schlaganfällen gute Resultate zeigt. HHcy und erniedrigtes Serumfolat sind bei Patienten mit Morbus Parkinson, multipler Sklerose und Depressionen häufig anzutreffen. Aufgrund klinischer Studien wird der HHcy bei der Entwicklung von Epilepsie ebenfalls eine kausale Rolle zugesprochen. Durch bestimmte Anti-Epileptika kann weiterhin die HHcy verstärkt werden. Bei Kindern mit unerklärbaren neurologischen Symptomen, Antriebsarmut oder schlechten intellektuellen Leistungen sollte ein Mangel an B-Vitaminen ausgeschlossen und ggf. behandelt werden. Für die Primär- und Sekundärprävention von verschiedenen neuropsychiatrischen Erkrankungen ist eine genügende Vitaminaufnahme mit der Nahrung wie auch Supplementation mit B-Vitaminen von Bedeutung, vor allem bei Personen mit ungenügender Vitaminaufnahme oder niedrigem Vitaminstatus.

Abstract

Elevated concentration of total homocysteine (Hcy) in plasma (> 12 µmol/l) is a risk factor for several diseases of the central nervous system. Epidemiological studies have shown a dose-dependent relationship between concentrations of Hcy and the risk for neurodegenerative diseases. Hcy is a marker for B-vitamin deficiency (folate, B₁₂, B₆). Hyperhomocysteinemia (HHcy) causes hypomethylation which is an important mechanism that links Hcy to dementia. Supplementation with vitamins B aims at reducing the risk of neurodegenerative diseases. Current evidence suggests that Hcy-lowering treatment has a positive effect for the secondary and primary prevention of stroke. HHcy is very common in patients with Parkinson disease particularly those who receive L-dopa treatment. Furthermore, a positive association has been reported between HHcy and multiple sclerosis. Moreover, HHcy and vitamin B deficiency are reported to have a causal role in depression, and epilepsy. In addition several anti-epileptic drugs cause secondary HHcy. Therefore, sufficient intakes of the vitamins are recommended for patients who have already developed neuropsychiatric diseases. Vitamin B deficiency should be suspected in children with development disorders, failure to thrive and unexplained neurological manifestations. Elderly people are also an important at-risk group where vitamin B deficiency and HHcy have been linked to neurodegenerative diseases. Treatment with folate, B₁₂, and B₆ can improve cerebral function. Preventive vitamin B supplementation and sufficient intake seem very important for secondary and primary prevention of neuropsychiatric disorders, especially in subjects with a low intake or status of the vitamins.

Schlüsselwörter

B-Vitamine - Homocystein - Neurodegeneration - Demenz - Alzheimer - Epilepsie

Key words

B-vitamins - homocysteine - neurodegeneration - dementia - Alzheimer - epilepsy

Full Text

References

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Prof. Dr. med. Wolfgang Herrmann

Institut für Kinische Chemie und Laboratoriumsmedizin, Universitätsklinikum des Saarlandes

Kirrberger Straße, Gebäude 57

66421 Homburg

Email: prof.wolfgang.herrmann@uniklinikum-saarland.de