Premium
Randomized trial of the effect of supplementation on the cognitive function of older people with subnormal cobalamin levels
Author(s) -
Kwok T.,
Tang C.,
Woo J.,
Lai W. K.,
Law L. K.,
Pang C. P.
Publication year - 1998
Publication title -
international journal of geriatric psychiatry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.28
H-Index - 129
eISSN - 1099-1166
pISSN - 0885-6230
DOI - 10.1002/(sici)1099-1166(199809)13:9<611::aid-gps832>3.0.co;2-o
Subject(s) - cobalamin , randomized controlled trial , cognition , medicine , psychology , gerontology , older people , psychiatry , vitamin b12
Background . Low serum cobalamin levels are often found in apparently normal older subjects. A major worry of leaving cobalamin deficiency untreated is that it may lead to subtle deterioration in cognitive function. Objectives . To investigate the effect of supplementation on the cognitive function of older people with cobalamin deficiency by a randomized trial. Methods . Fifty Chinese subjects more than 60 years old with serum cobalamin level <120 pmol/l were randomized into supplement and control groups. Fasting serum methylmalonic acid levels (MMA) were measured. A battery of neuropsychological tests was administered. The supplement group received intramuscular cyanocobalamin injections, while the control group received no intervention. They were followed up at around 4 months. Results . 78% of the subjects had raised MMA, indicating metabolic cobalamin deficiency. Supplemented subjects improved in performance IQ, but the amount of improvement was not significantly more than that of control subjects. Moreover, the supplement group fared worse than the control group at follow‐up in some motor function scores. Three out of seven demented subjects had improvement in Mini‐Mental State Examination scores, but there was no consistent improvement in other neuropsychological scores. Conclusions . This study suggested that cobalamin deficiency did not invariably cause cognitive impairment in older people. There remain the possibilities that cobalamin deficiency causes cognitive impairment or exacerbates coexisting dementia in some older people. © 1998 John Wiley & Sons, Ltd.