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Dement Geriatr Cogn Disord 2003;16:145–150

Vitamin B12-B6-Folate Treatment Improves Blood-Brain Barrier Function in Patients with Hyperhomocysteinaemia and Mild Cognitive Impairment

Lehmann M. · Regland B. · Blennow K. · Gottfries C.G.

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Department of Psychiatry and Neurochemistry, Institute of Clinical Neuroscience, Sahlgrenska University Hospital, Mölndal, Sweden

Corresponding Author

Björn Regland

Institute of Clinical Neuroscience

Department of Psychiatry and Neurochemistry, Sahlgrenska University Hospital

SE–43180 Mölndal (Sweden)

Tel. +46 31 343 1000, Fax +46 31 776 9055, E-Mail bjorn.regland@vgregion.se

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Thirty patients had mild cognitive impairment and increased homocysteine levels in serum. On average, they were supplemented orally with a high dose of a vitamin B12-B6-folate combination for 270 days. All patients had normal serum B12 and folate levels at baseline. Cerebrospinal fluid levels of the tau protein (CSF-tau) and the albumin ratio were measured before and after treatment. The serum homocysteine levels were normalised after treatment. The albumin ratio significantly correlated with vascular risk factors. At baseline, the ratio was higher in the patients in comparison with age-matched controls. After treatment, the ratio was significantly reduced, which may indicate a tightening of the blood-brain barrier. The CSF-tau levels did not change significantly although there was a numeric decline. None of the patients progressed into dementia during the treatment period. When treated with a vitamin B12-B6-folate combination, patients with mild cognitive impairment and hyperhomocysteinaemia appear to improve their blood-brain barrier function. They may also stabilise their cognitive status. Further investigations are warranted on the role of blood-brain barrier dysfunction in the pathogenesis of dementia.

© 2003 S. Karger AG, Basel


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Article / Publication Details

First-Page Preview
Abstract of Original Research Article

Received: February 02, 2003
Published online: July 04, 2003

Number of Print Pages: 6
Number of Figures: 2
Number of Tables: 1

ISSN: 1420-8008 (Print)
eISSN: 1421-9824 (Online)

For additional information: https://www.karger.com/DEM