BDNF val66met polymorphism and depressive disorders in patients with acute coronary syndrome.

INTRODUCTION

Brain-derived neurotrophic factor (BDNF) may be the key to understanding the development of depression in patients with acute coronary syndrome (ACS), as it is associated with both conditions. Because the expression of BDNF is influenced by genetic polymorphisms, in this study we investigated the association between the BDNF polymorphism val66met and both the risk of depression in ACS and the treatment response.

METHODS

Among the 969 patients with recent ACS at baseline, 711 were re-evaluated after 1 year of follow-up. Depressive disorder status was assessed according to the DSM-IV criteria both at baseline and at follow-up. Baseline prevalence, follow-up incidence, and the persistence of depression were also determined. Of the 378 patients diagnosed with depression at baseline, 255 were randomized to a 24-week double-blind placebo-controlled trial of escitalopram; the remaining 123 received the usual care. Associations between the BDNF val66met polymorphism and both depression status and treatment response were investigated using logistic regression models.

RESULTS

The prevalence and persistence, but not the incidence of depressive disorders were significantly associated with BDNF met alleles. Patients in the escitalopram group who carried the met allele had a significantly higher rate of remission than those who did not. Depressive disorders tended to persist at 1 year in patients managed with placebo or medical treatment only, and particularly those patients positive for BDNF met alleles, although the difference was not statistically significant.

LIMITATIONS

The generalizability should be considered since this study conducted in a single center.

CONCLUSIONS

ACS patients positive for BDNF met alleles are vulnerable to depressive disorders at baseline and to its persistence. Antidepressant treatment may be effective in this subgroup of patients and may prevent the persistence of depression.