Antidepressant treatment response is associated with changes in peripheral DNA methylation over time, as well as corresponding alterations in gene expression. Significance Statement Major depressive disorder (MDD) is commonly treated with antidepressants; however, many people do not respond to treatment. In order to better understand the molecular changes that occur during antidepressant treatment, we analyzed DNA methylation and gene expression in the blood of 154 individuals with MDD who were treated with escitalopram or desvenlafaxine. We found 10 methylation sites within 10 genes whose methylation levels changed over time in relation to clinical improvement, and whose levels of expression were related to both methylation and antidepressant response.
Fiori et al. (2026) studied this question.