Vitamin B12 Deficiency In Spinal Cord Injury: A Retrospective Study

Abstract

Background/Objective: Vitamin B12 (or cobalamin) deficiency is well known in geriatric patients, but not in those with spinal cord injury (SCI) . This retrospective study describes vitamin B1 2 deficiency in SCI.Methods: This study utilized a retrospective chart review of patients with SCI who had received serum vitamin B1 2 testing over the last 1 0 years.Results: Probable vitamin B1 2 deficiency was noted in 1 6 patients with SCI. Twelve patients had subnormal serum vitamin B12 levels (< 220 pg/ml), whereas 4 patients had low-normal vitamin B12 levels (< 300 pg/ml) with neurologic and/or psychiatric symptoms that improved following vitamin B1 2 replacement. Classic findings of paresthesias and numbness often were not evident; such findings likely were masked by the pre-existing sensory impairment caused by SCI. Of the 1 6 SCI patients, 7 were ambulatory; 4 of the 7 presented with deterioration of gait. In addition, 3 of the 1 6 SCI patients presented with depression and fatigue, 2 had worsening pain , 2 had worsening upper limb weakness, and 2 had memory decline. Of the 1 2 patients with subnormal serum vitamin B12 levels, 6 were asymptomatic. Classic laboratory findings of low serum vitamin B1 2 , macrocytic red blood cell indices, and megaloblastic anemia were not always present. Anem ia was identified in 7 of the 1 6 patients and macrocytic red blood cells were found in 3 of the 1 6 patients. Only 1 of the 1 6 SCI patients had a clear pathophysiologic mechanism to explain the vitamin B12 deficiency (ie, partial gastrectomy); none of the patients were vegetarian. Twelve of the SCI patients appeared to experience clinical benefits from cyanocobalamin replacement (some patients experienced more than 1 benefit), including reversal of anemia (5 patients), improved gait (4 patients), improved mood (3 patients), improved memory (2 patients), reduced pain (2 patients) , strength gain (1 patient), and reduced numbness (1 patient).Conclusion: It is recommended that physicians consider vitamin B1 2 deficiency in their patients with SCI , particularly in those with neurologic and/ or psychiatric symptoms. These symptoms often are reversible iftreatment is initiated early.