Lithium treatment and risk of neurocognitive disorders in older patients with bipolar disorder: A systematic review

Bipolar disorder is a chronic mental illness that requires long-term treatment. Reports from patients of cognitive dulling have prompted research into the impact of long-term Lithium treatment on cognition. The present systematic review aimed to investigate the effects of Lithium on neurocognitive disorder outcomes in older patients with bipolar disorder.

A systematic literature search was conducted in four databases: PubMed, Scopus, ScienceDirect and EBSCO. Study inclusion was based on concrete inclusion/exclusion criteria. The literature search and the final study selection were conducted in four stages. Included studies were assessed for quality using the Newcastle-Ottawa Quality Assessment Scale for cohort studies, and the Modifications to the Newcastle-Ottawa Scale for cross-sectional studies.

The original search yielded a total of 8285 records. Among these, nine studies were included in the systematic review. Eight out of nine studies did not support an association between Lithium treatment and increased risk of neurocognitive disorders. One study found that the association between bipolar disorder and neurocognitive disorder may be mediated by Lithium treatment.

There is no conclusive evidence that long-term Lithium treatment is harmful with respect to neurocognitive outcomes in older patients with bipolar disorder. Beyond its efficacy as a mood-stabilizer, accumulating evidence supports Lithium's neurotrophic effects. To date, there is enough evidence to support Lithium maintenance as a first-line treatment for older patients with bipolar disorder.