Cobalamin supplementation improves cognitive and cerebral function in older, cobalamin-deficient persons.
BACKGROUND
Mild cobalamin (Cbl) deficiency is frequently found in older persons and is associated with cognitive and cerebral abnormalities. The effects of Cbl supplementation on these abnormalities are largely unknown.


METHODS
In a single-blind, placebo-controlled intervention study, 16 healthy community-dwelling elderly subjects with low plasma Cbl concentration and no cognitive impairments were studied. Subjects underwent 1 month of treatment with placebo, followed by 5 months of treatment with intramuscular injections of hydroxycobalamin. Before and after measurements of plasma cobalamin, total homocysteine (tHcy), methylmalonic acid (MMA), quantitative electroencephalograph (qEEG), and psychometric tests were taken.


RESULTS
After Cbl supplementation, plasma Cbl concentrations increased, and plasma MMA and tHcy concentrations decreased. The performance on the Verbal Word Learning Test, Verbal Fluency and Similarities improved. qEEG showed more fast activity and less slow activity. Lower plasma tHcy concentrations were related to increased fast activity on qEEG on the one hand and improved performance on the Verbal Word Learning Test and Similarities on the other. Increased fast or decreased slow activity on qEEG was associated with improved performance on the Verbal Word Learning Test, Similarities and Verbal Fluency.


CONCLUSIONS
Electrographic signs of improved cerebral function and improved cognitive function were found after Cbl supplementation in older subjects with low plasma Cbl concentrations who were free of significant cognitive impairment. These improvements were related to a reduction of plasma tHcy concentration.
van Asselt
D Z
DZ
Department of Geriatric Medicine, University Medical Centre Nijmegen, The Netherlands. D.vanAsselt@czzoger.azn.nl
Pasman
J W
JW
van Lier
H J
HJ
Vingerhoets
D M
DM
Poels
P J
PJ
Kuin
Y
Y
Blom
H J
HJ
Hoefnagels
W H
WH
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology* / Q000523:psychology; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D003071:Cognition / Q000187:drug effects*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D006879:Hydroxocobalamin / Q000627:therapeutic use*; D008297:Male; D008764:Methylmalonic Acid / Q000097:blood; D016037:Single-Blind Method; D014806:Vitamin B 12 Deficiency / Q000188:drug therapy* / Q000503:physiopathology* / Q000523:psychology
D008764:Methylmalonic Acid; D006879:Hydroxocobalamin