title: Serum cobalamin and methylmalonic acid in Alzheimer dementia.
abstract: The cobalamin status was evaluated in Alzheimer dementia (n = 26), other dementias (n = 24), various gerontopsychiatric disorders (n = 25), and in neuro-psychiatrically healthy controls (n = 20). Supplementing serum cobalamin we measured methylmalonic acid (MMA), a metabolite accumulating early in cobalamin deficiency. Subnormal cobalamin and/or clearly elevated MMA concentrations were found in 11 cases: 7 Alzheimer patients (27%), 2 with other dementias (8%), one psychiatric patient (4%), and one control (5%). None presented the typical neurologic features of cobalamin deficiency and macrocytosis was found in only one. The mean cobalamin concentration was significantly lower in Alzheimer patients (179 +/- 18 pmol/l) than in the age-matched controls (256 +/- 23 pmol/l) (p = 0.013) and the other patient groups. Correspondingly, the mean MMA level was higher in the Alzheimer group (0.480 +/- 0.062 mumol/l) than in any other diagnostic group (controls: 0.347 +/- 0.040 mumol/l). Comparing the Alzheimer group to the other groups as a whole, the elevation was significant (p = 0.0097). Our findings indicate that Alzheimer patients are particularly prone to cobalamin deficiency, and even subtle biochemical signs of deficiency seem to justify treatment.
authors.affiliation: University Department of Neurology, Aarhus Kommunehospital, Denmark.
authors.forename: M O
authors.initials: MO
authors.lastname: Kristensen
authors.forename: N C
authors.initials: NC
authors.lastname: Gulmann
authors.forename: J E
authors.initials: JE
authors.lastname: Christensen
authors.forename: K
authors.initials: K
authors.lastname: Ostergaard
authors.forename: K
authors.initials: K
authors.lastname: Rasmussen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000175:diagnosis; D003704:Dementia / Q000097:blood* / Q000175:diagnosis; D003937:Diagnosis, Differential; D004909:Erythrocyte Indices; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005492:Folic Acid / Q000097:blood; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000097:blood / Q000175:diagnosis; D008764:Methylmalonic Acid / Q000097:blood*; D008875:Middle Aged; D012016:Reference Values; D012307:Risk Factors; D014805:Vitamin B 12 / Q000097:blood*; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000175:diagnosis
chemical_list: D008764:Methylmalonic Acid; D005492:Folic Acid; D014805:Vitamin B 12