Vitamin B12 measurements across neurodegenerative disorders

Nijee S Luthra; Ariane H Marcus; Nancy K Hills; Chadwick W Christine

doi:10.1186/s40734-020-00085-8

Vitamin B12 measurements across neurodegenerative disorders

J Clin Mov Disord. 2020 Mar 12:7:3. doi: 10.1186/s40734-020-00085-8. eCollection 2020.

Authors

Nijee S Luthra¹, Ariane H Marcus², Nancy K Hills³, Chadwick W Christine²

Affiliations

¹ 1Department of Neurology, University of California, San Francisco, 1635 Divisadero, Suite 520-530, San Francisco, CA 94115 USA.
² 2Department of Neurology, University of California, San Francisco, 400 Parnassus Avenue, San Francisco, CA 94122 USA.
³ 3Department of Epidemiology and Biostatistics, University of California, San Francisco, 550 16th Street, San Francisco, CA 94158 USA.

Abstract

Background: Vitamin B12 deficiency causes a number of neurological features including cognitive and psychiatric disturbances, gait instability, neuropathy, and autonomic dysfunction. Clinical recognition of B12 deficiency in neurodegenerative disorders is more challenging because it causes defects that overlap with expected disease progression. We sought to determine whether B12 levels at the time of diagnosis in patients with Parkinson's disease (PD) differed from those in patients with other neurodegenerative disorders.

Methods: We performed a cross-sectional analysis of B12 levels obtained around the time of diagnosis in patients with PD, Multiple System Atrophy (MSA), Dementia with Lewy Bodies (DLB), Alzheimer's disease (AD), Progressive Supranuclear Palsy (PSP), Frontotemporal Dementia (FTD), or Mild Cognitive Impairment (MCI). We also evaluated the rate of B12 decline in PD, AD, and MCI.

Results: In multivariable analysis adjusted for age, sex, and B12 supplementation, we found that B12 levels were significantly lower at time of diagnosis in patients with PD than in patients with PSP, FTD, and DLB. In PD, AD, and MCI, the rate of B12 decline ranged from - 17 to - 47 pg/ml/year, much greater than that reported for the elderly population.

Conclusions: Further studies are needed to determine whether comorbid B12 deficiency affects progression of these disorders.

Keywords: Cyanocobalamin; Subacute combined degeneration; Vitamin B12.