Association of CNR1 genotypes with changes in neurocognitive performance after eighteen-month treatment in patients with first-episode psychosis.

INTRODUCTION

We analyzed the association of cannabinoid receptor CNR1 genotypes with changes in neurocognitive performance in patients with first-episode psychosis (FEP) after 18 months of treatment. Our secondary aim was to analyze the association of CNR1 genotypes with changes of perceived levels of stress.

METHODS

We enrolled a sample of 159 patients with FEP from two Croatian psychiatric hospitals between 2014 and 2017. Patients were assessed at baseline and after 18 months. We analyzed the associations of changes in neurocognitive test results and the perceived levels of stress with CNR1 polymorphic loci (rs7766029 and rs12720071) in 121 patients.

RESULTS

In the analysis adjusted only for baseline neurocognitive test scores, carriers of rs7766029 CC genotype had significantly (with false discovery rate, FDR < 15%) higher improvement in verbal memory (Wechsler, Wechsler 30') and attention (Digit span F) compared with other participants. In such analysis, rs12720071 carriers of AG genotype had significantly (FDR < 15%) higher improvement in executive functions (Block design), but lower improvement in language functions than AA carriers. In the fully adjusted analysis for age, sex, cannabis use and negative symptoms, only the association of rs7766029 genotypes with the change in the Weschler 30' score was significant (FDR < 15%). In the analysis adjusted only for the baseline neurocognitive tests' scores, both rs7766029 and rs12720071 genotypes were significantly associated with the change in perceived levels of stress (FDR < 15%). In the fully adjusted analysis, only the association with rs7766029 genotype remained significant.

CONCLUSIONS

The rs7766029 CNR1 variants may moderate changes in neurocognitive performance as well as in perceived levels of stress of patients with FEP over time.