The protective effect of vitamin B12 on neuropsychiatric symptoms in dementia-free older adults in a multi-ethnic population

Yingqi Liao; Haoran Zhang; Yaping Zhang; Cheuk Ni Kan; Rachel Sher Li Chia; Yuek Ling Chai; Ching-Yu Cheng; Christopher Chen; Xin Xu

doi:10.1016/j.clnu.2024.11.037

The protective effect of vitamin B12 on neuropsychiatric symptoms in dementia-free older adults in a multi-ethnic population

Clin Nutr. 2024 Nov 24:44:25-32. doi: 10.1016/j.clnu.2024.11.037. Online ahead of print.

Authors

Yingqi Liao¹, Haoran Zhang², Yaping Zhang², Cheuk Ni Kan¹, Rachel Sher Li Chia¹, Yuek Ling Chai¹, Ching-Yu Cheng³, Christopher Chen⁴, Xin Xu⁵

Affiliations

¹ Memory, Aging and Cognition Centre, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
² School of Public Health and the Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, China.
³ Centre for Innovation and Prevision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.
⁴ Memory, Aging and Cognition Centre, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
⁵ Memory, Aging and Cognition Centre, Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; School of Public Health and the Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: xuxinsummer@zju.edu.cn.

PMID: 39608085
DOI: 10.1016/j.clnu.2024.11.037

Abstract

Background and aims: Vitamin B12 deficiency has been associated with neuropsychiatric symptoms (NPS), but the relationship between vitamin B12 and NPS remains unclear prior to the onset of dementia. The study aims to examine the association between vitamin B12 and NPS in dementia-free Asian older adults.

Methods: This is a cross-sectional population-based study where multi-ethnic community-dwelling Asian participants (i.e. Chinese, Malay, Indian) aged ≥60 years underwent comprehensive neuropsychological and clinical assessments including the examination of clinical history and the collection of blood samples. NPS and subsyndromes were evaluated using the Neuropsychiatric Inventory (NPI). Serum vitamin B12 and homocysteine (Hcy) concentration were measured by competitive immunoassays. To analyse the relationship between vitamin B12 and NPS, hierarchical linear regression, multinomial regression and moderation analyses were performed.

Results: A total of 798 dementia-free individuals (age = 69.7 ± 6.5 years old, F = 408 (51.1 %)) were included in the current study. There were 80 (10 %) individuals with clinically relevant NPS (i.e. NPI scores ≥4). Higher vitamin B12 was associated with lower NPI total scores (p = 0.030) and apathy (p = 0.005), after controlling for age, sex, ethnicity, cognitive functioning, socioeconomic status and Hcy concentration. Participants with higher vitamin B12 was also less likely to have clinically relevant apathy (p = 0.007). The moderation effect of Hcy and cognitive functioning on the inverse association between vitamin B12 and NPS was observed.

Conclusions: A protective effect of vitamin B12 on NPS and subsyndromes was observed in a multi-ethnic Asian cohort of dementia-free individuals. Future longitudinal studies are required to further elucidate the pathophysiological mechanisms between vitamin B12 and NPS in diverse ethnic groups.

Keywords: Dementia; Mild cognitive impairment; Neuropsychiatric symptoms; Nutrition; Vitamin B.