R. Eastley et al., Vitamin B12 deficiency in dementia and cognitive impairment: The effects of treatment on neuropsychological function, INT J GER P, 15(3), 2000, pp. 226-233
Background. Vitamin B12 assay is part of the routine investigation of demen
tia, although few studies have investigated the effects of treatment on cog
nition. We examined the effects of B12! treatment on neuropsychological fun
ction and disease progression in patients presenting with dementia or cogni
tive impairment.
Methods. From 1432 patients who were: assessed at the Bristol Memory Disord
ers Clinic, 125 patients with low serum B12 were identified. Sixty-six pati
ents presenting with dementia, and 22 with cognitive impairment were seen f
or a second assessment after treatment. Changes in neuropsychological test
scores were compared with those of patients with normal serum B12, matched
by age and diagnosis.
Results. The majority of patients with low serum B12 had normal Hb and MCV
values. We found no cases of reversible B12 deficiency dementia. The B12 tr
eatment patients who presented with dementia showed no significant improvem
ent, and no less deterioration, in their neuropsychological function than t
heir matched group. However, a treatment effect was demonstrated among the
patients presenting with cognitive impairment. These improved: significantl
y compared to matched patients on the verbal fluency test (p < 0.01).
Conclusion. All patients with cognitive impairment should be investigated F
or B12 deficiency. Vitamin B12 treatment may improve frontal lobe and langu
age function in patients with cognitive impairment, but rarely reverses dem
entia. Copyright (C) 2000 John Wiley & Sons, Ltd.