The electroencephalogram in pernicious anemia.

EEGs were recorded in 54 patients with pernicious anemia. Six patients without nervous system involvement had normal EEGs, 10 patients with spinal cord or peripheral nervous system involvement had normal or minimally abnormal EEGs, 17 of 19 patients with evidence of mental dysfunction had abnormal EEGs with the most consistent finding being an excess of theta slowing, and 19 patients with pernicious anemia and other neurologic diseases showed EEG findings reflecting the complicating disease process. In general, the EEG abnormalities in patients with pernicious anemia correlated well with the presence of cerebral dysfunction but not with the degree of anemia. The EEG was also a good indicator for detecting and confirming other intracranial disease processes unrelated to pernicious anemia.