维生素Bn 12缺乏最常引起脊髓亚急性联合变性和贫血，这已被临床医师广泛关注，并能被早期诊治以逆转症状。但是，维生素Bn 12缺乏尚可引起不同程度的认知功能障碍，而该现象目前却不能被及早诊治，导致不可逆损害，最后出现严重痴呆。因此，本文围绕维生素Bn 12缺乏与轻度认知功能障碍(MCI)的相关性的研究进展予以综述，以期提高临床医师对二者关系的认识。n “,”Vitamin Bn 12 deficiency, the most common cause of subacute degeneration of the spinal cord and anemia, has been widely concerned by clinicians and can be treated early to reverse symptoms. However, vitamin Bn 12 deficiency can cause varying degrees of cognitive impairment that cannot be diagnosed and treated at early stage, resulting in irreversible damage and eventually severe dementia. This article reviews the correlation between vitamin Bn 12 deficiency and mild cognitive impairment, in order to improve the knowledge of clinicians.n