Higher polygenic risk scores for bipolar disorder were associated with favorable treatment outcomes after lithium augmentation in antidepressant non-responders with unipolar depression.

Question Are polygenic risk scores (PRS) for major psychiatric disorders associated with favorable treatment outcomes after lithium augmentation (LA) in major depression?

Findings In this cohort study with 193 patients with major depressive disorder (MDD) who did not respond to antidepressants, the PRS for bipolar disorder (BIP) was significantly associated with response and remission after at least 4 weeks of LA. Additionally, we found an association between the MDD-PRS and LA response.

Meaning Individuals with a higher polygenic burden for BIP and lower polygenic burden for MDD are more likely to experience favorable treatment outcomes following LA, offering new opportunities for personalized medicine approaches.