Effects of N-acetyl cysteine on cognitive function in bipolar disorder.

AIMS: Bipolar disorder is characterized by progressive changes in cognition with declines in executive functioning, memory and sustained attention. Current pharmacotherapies for bipolar disorder target mood symptoms but have not addressed these cognitive changes resulting in euthymic individuals who still experience cognitive deficits. N-acetyl cysteine (NAC) has been shown to have effects on antioxidant status, glutamate transmission, inflammation and neurogenesis. Adjunctive treatment with NAC improves the symptoms experienced by those with bipolar disorder, particularly depression, and it was hypothesized that cognition may also be improved following NAC treatment.

METHODS: As part of a larger randomized, double-blind, placebo-controlled trial, participants in the current report were tested at baseline and 6 months to assess changes in cognitive function following either 2000 mg of NAC daily or placebo.

RESULTS: This study failed to find changes in cognitive function following treatment with NAC compared to placebo.

CONCLUSIONS: While an important pilot study, this study had a small sample size and included a limited battery of cognitive tests. Further investigations on the effects of NAC on cognitive performance in bipolar disorder are required.