PS162. Genetic role of CSNK1E on circadian and childhood characteristics of the patients with major depressive disorder

Aim: Homocysteine and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism have been investigated as risk factors for depression and ACS separately, but not for depression comorbid with ACS. This study aimed to investigate whether homocysteine and MTHFR gene are associated with occurrence of depressive disorder in ACS. Methods and results: A sample of 969 patients with recent ACS were recruited and 711 followed 1 year later. Depressive disorder was diagnosed according to DSM-IV criteria, and classified as baseline prevalent, and follow-up incident or persistent disorder according to status at the two examinations. Plasma homocysteine concentration and the MTHFR C677T polymorphism were assayed, and a range of demographic and clinical characteristics evaluated as covariates. A higher homocysteine concentration was independently associated with prevalent depressive disorder at baseline irrespective of MTHFR genotype; and with both incident and persistent depressive disorder at follow-up only in the presence of TT genotype. MTHFR genotype was not itself associated with depressive disorder after ACS. Conclusions: Plasma homocysteine could be a biomarker for depressive disorder particularly in the acute phase of ACS. Focused interventions for those with higher homocysteine level and MTHFR TT genotype might reduce the risk of later depressive disorder. PS161 Association study of polymorphism in the serotonin transporter gene promoter, methylation profiles, and expression in patients with major depressive disorder