The effect of atorvastatin on cognition and mood in bipolar disorder and unipolar depression patients: A secondary analysis of a randomized controlled trial.

Abstract Objectives Statins have recently been linked to having effects on cognition and mood in mood disorders, though results are mixed. In this paper, we use data from a recent randomized controlled trial (RCT) to examine the effect of statins on cognition and mood in patients with Bipolar Disorder (BD) and Major Depressive Disorder (MDD). Methods This is a secondary analysis of a randomized, double-blind, placebo-controlled clinical trial (n = 60) originally designed to examine the effect of atorvastatin (n = 27) versus placebo (n = 33) for lithium-induced diabetes insipidus in BD and MDD patients who were using lithium. For this analysis, the primary outcome was global cognition Z-score at 12-weeks adjusted for baseline. The secondary cognition outcomes were (1) Screen for Cognitive Impairment in Psychiatry (SCIP), and (2) executive function Z-score. The primary mood outcome (secondary outcome of this analysis) was depression relapse during 12-week follow-up (Mongomery Asberg Depression Rating Scale (MADRS) ≥10). The secondary mood outcomes were (1) relapse rate into a manic episode, and (2) relapse rate into any mood episode. Results After 12 weeks follow-up, atorvastatin and placebo groups did not differ in terms of global cognition Z-score (β = −0.009287 (−0.1698,0.1512), p-value = 0.91). Similarly, composite Z-scores for SCIP and executive functions did not differ significantly. Depression relapse during 12-week follow-up was not significantly different between the groups (χ2 (1) = 0.148, p-value = 0.70). Similarly, there was no difference between groups regarding relapse into mania. Conclusion In BD and MDD patients with lithium-induced nephrogenic diabetes insipidus randomized to atorvastatin or placebo, we found no significant differences in cognition and mood outcomes at 12-week follow-up.