Dementia Associated With Vitamin B₁₂ Deficiency

Vitamin B₁₂ deficiency has long been associated with a wide variety of hematological, neurological, and psychiatric disorders. The role of vitamin B₁₂ deficiency as one of the few treatable causes of dementia, however, is still controversial. The authors report on 2 elderly patients suffering from cognitive impairment and psychotic symptomatology probably related to cobalamin deficiency, who showed improvement after parenteral vitamin B₁₂ substitution. The literature concerning the pathophysiology and the diagnostic and therapeutic aspects of cobalamin deficiency is reviewed.