Potential outcome factors in subacute combined degeneration: review of observational studies.
BACKGROUND
Subacute combined degeneration is an acquired myelopathy caused by vitamin B12 deficiency. Therapy with B12 leads to improvement in most but to complete recovery in only a few patients. Prognostic indicators in subacute combined degeneration are unknown; therefore, predicting complete recovery of neurologic deficits is challenging.


OBJECTIVE
To identify potential correlates of outcome and to generate hypotheses concerning predictors of complete resolution of neurologic deficits in subacute combined degeneration.


METHODS
We searched EMBASE (1974 to October 2005), MEDLINE (1968 to October 2005), and references from identified reports. REPORTS SELECTION: Reports of patients with subacute combined degeneration containing results of magnetic resonance imaging (MRI) and description of outcome and 1 patient treated by the authors.
We extracted data from 45 reports and 57 patients (36 males, 21 females; age range: 10 to 81) with a diagnosis of subacute combined degeneration, and estimated the strength of association between clinical, laboratory, and radiological factors and complete resolution of signs and symptoms.


RESULTS
Eight patients (14%) achieved clinical resolution and 49 (86%) improved with B12 therapy. The absence of sensory dermatomal deficit, Romberg, and Babinski signs were associated with a higher complete resolution rate. Patients with MRI lesions in < or = 7 segments and age less than 50 also appear to have higher rates of complete resolution.


CONCLUSIONS
B12 therapy is reported to stop progression and improve neurologic deficits in most patients with subacute combined degeneration. However, complete resolution only occurs in a small percentage of patients and appears to be associated with factors suggestive of less severe disease at the time of diagnosis.
Vasconcelos
Olavo M
OM
Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
Poehm
Erika H
EH
McCarter
Robert J
RJ
Campbell
William W
WW
Quezado
Zenaide M N
ZM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy; D016896:Treatment Outcome; D014805:Vitamin B 12 / Q000627:therapeutic use*; D014806:Vitamin B 12 Deficiency / Q000000981:diagnostic imaging* / Q000188:drug therapy
D014805:Vitamin B 12