One hundred forty-eight Caucasian patients with a current unipolar major depressive episode (DSM IV-TR) were genotyped for the BDNFVal66Met polymorphism and assessed at baseline and after 3 and 6 months of antidepressant treatment for the 'Homoeostasis model assessment of insulin resistance' (HOMA-IR) index, a valid measure of insulin resistance based on fasting plasma insulinaemia and glycaemia.
Plasma BDNF levels were analyzed in samples from 61 medicated patients with a major depressive episode and 50 healthy controls, and in patient samples following a course of ECT.
Our results show a measurable, coherent, and functional BDNF pathway based on the BDNFVal66Met polymorphism and plasma BDNF levels in patients with a current MDE.
The present study suggests that the acute effect of lamotrigine augmentation therapy for a major depressive episode is not related to either BDNF or IL-6, at least in patients with treatment-resistant depressive disorder.