Dharmarajan T S, Adiga G U, Norkus Edward P
New York Medical College, Valhaila, NY, USA.
Geriatrics. 2003 Mar;58(3):30-4, 37-8.
Vitamin B12 deficiency is a common but under-recognized, yet easily treatable disorder in older adults. Although several causes exist, food-cobalamin malabsorption is now believed to be the most common etiology. Complications of vitamin B12 deficiency are myriad, ranging from lethargy and weight loss to dementia. Causes of deficiency include failure to separate vitamin B12 from food protein, inadequate ingestion, absorption, utilization, and storage as well as drug-food interactions leading to malabsorption and metabolic inactivation. The roles of B12 deficiency, elevated homocysteine and elevated methylmalonic acid in various disease states are still evolving. Timely screening and replacement of vitamin B12 will help prevent many complications.
维生素B12缺乏症在老年人中很常见，但未得到充分认识，然而它却是一种易于治疗的疾病。虽然存在多种病因，但目前认为食物钴胺素吸收不良是最常见的病因。维生素B12缺乏症的并发症多种多样，从嗜睡、体重减轻到痴呆。缺乏的原因包括无法将维生素B12与食物蛋白分离、摄入不足、吸收不良、利用和储存不当，以及导致吸收不良和代谢失活的药物-食物相互作用。维生素B12缺乏、同型半胱氨酸升高和甲基丙二酸升高在各种疾病状态中的作用仍在不断演变。及时筛查和补充维生素B12有助于预防许多并发症。
