Subnormal serum vitamin B-12 and behavioural and psychological symptoms inAlzheimer's disease

The objective of this study was to examine whether patients with Alzheimer' s disease (AD) with subnormal vitamin B-12 levels Show more frequent behavi oural and psychological symptoms of dementia (BPSD) than AD patients with n ormal vitamin B-12 levels. The design was a prospective case-control study. The study took place at a memory-clinic of a department of geriatric medic ine in a teaching hospital. There were seventy-three consecutive outpatient s with probable AD, including 61 patients with normal and 12 patients with subnormal (<200 pg/ml) vitamin B-12. BPSD were measured using the subscales disturbed behaviour and mood of the Nurses' Observation Scale for Geriatri c Patients (NOSGER), the Cornell Scale for Depression and the four criteria for personality change in dementia from the International Classification o f Diseases (ICD-10). Controlling for dementia duration and degree of severi ty of the cognitive deficits, there were significant inverse associations b etween vitamin B-12 status and ICD-10 irritability (p = 0.045) and NOSGER s ubscale disturbed behaviour (p = 0.015). Low vitamin B-12 Serum levels are associated with BPSD in AD. Vitamin B-12 could play a role in the pathogene sis of behavioural changes in AD. Copyright (C) 2000 John Wiley & Sons, Ltd .