Title:Effect of Lithium on Neurocognitive Functioning
VOLUME: 13 ISSUE: 8
Author(s):Janusz K. Rybakowski
Affiliation:Department of Adult Psychiatry, Poznan University of Medical Sciences, ul.Szpitalna 27/33, 60-572 Poznan, Poland.
Keywords:Bipolar, cognitive functions, dementia, lithium, neuroprotection, neurotoxicity.
Abstract:Lithium is the first choice drug for the long-term prophylaxis of depressive and manic episodes
in bipolar disorder (BD). Both experimental and clinical studies show either neuroprotective or
neurotoxic effects of lithium on brain function, reflecting the propensity of lithium to affect different
brain structures. In most experimental studies, lithium, in therapeutic doses, exerts a favourable influence
on various cognitive functions. Patients with BD present cognitive problems of mild intensity
across mood states, worsening during manic or depressive episodes and, sometimes, also persisting
during euthymia. Meta-analyses, comparing bipolar patients treated with lithium with those without
the drug show a moderate negative effect of this drug on cognition and, among clinicians, negative
impact on cognitive functioning is considered one of the side effect of the drug. In some studies, the effect of lithium on
cognitive function in BD was shown to be associated with a prophylactic efficacy of the drug against an occurrence of affective
episodes. Excellent lithium responders, having no affective recurrences during lithium therapy, perform on cognitive
functions tests similar to those of age-matched, healthy control subjects. Some studies also found a reduction by lithium
the risk of dementia in BD subjects. Possible mechanisms alleviating negative impact of lithium on cognition in BD
can be connected with the prevention of affective recurrences, improvement of neural plasticity, antiviral action against
herpes infection and using the drug in appropriate doses.