Neuroticism but not omega-3 fatty acid levels correlate with early responsiveness to escitalopram

Abstract

Background: Omega-3 fatty acid (O3FA) levels and dimensional personality measures have been associated with major depression and the course of depressive illness. We sought to study the utility of O3FA levels and dimensional personality measures as predictors of early improvement with escitalopram.

Methods: Twenty-four participants were enrolled in an open-label trial of escitalopram 10 mg/d for 4 weeks. Baseline erythrocyte O3 levels and dimensional personality assessments were obtained.

Results: Using a conservative, intention-to-treat analysis, baseline neuroticism (r = -0.57; P = .007), as measured by the Revised NEO Personality Inventory but not erythrocyte O3 levels, was correlated with improvements on escitalopram. A facet analysis of the neuroticism domain showed the relationship with antidepressant response to be focused on trait anxiety (r = -0.65; P = .002).

Conclusions: Anxiety may have important prognostic implications on subsequent response to selective serotonin reuptake inhibitors, such as escitalopram.

Figure 1. Flow of participants

A total of 72 potential participants were screened for eligibility, of whom 24 consented to participate in the study. There was one screen failure for pregnancy. Five participants dropped out before completion of the 4-week trial, 4 of whom had at least one follow-up assessment.

Figure 2. Relationship between neuroticism and antidepressant response

MADRS: Montgomery-Åsberg Depression Rating Scale; NEO-PI-R: Revised NEO Personality Inventory. As evident in the scatterplot (left), the domain of neuroticism was highly correlated with change in the MADRS while on escitalopram 10 mg/d (r = −0.57; P = .007). This association was further confined to the neuroticism facet of anxiety (r = −0.65; P = .002), as illustrated in the adjacent scatterplot (right). Raw scores on the NEO-PI-R were used for domains and facets.