On the safety of long-term treatment with lithium.

Thirteen patients with bipolar affective illness who had received lithium therapy for 1-5 years were tested retrospectively for evidence of cortical dysfunction. Data on patients younger than 55 show no abnormalities on the Halstead-Reitan Neuropsychological Battery and suggest that chronic lithium therapy is relatively safe. Significantly elevated Halstead Impairment indexes were observed among elderly patients, but these data are difficult to interpret.