Abstract
Treatment of medical patients with the inflammatory cytokine, interferon-α (IFN-α), is frequently associated with the development of clinical depressive symptomatology. Several important biological correlates of the effect of IFN-α on mood have been described, but the neuropsychological changes associated with IFN-α treatment are largely unexplored. The aim of the present preliminary study was to assess the effect of IFN-α on measures of emotional processing. We measured changes in emotional processing over 6-8 weeks in 17 patients receiving IFN-α as part of their treatment for hepatitis C virus infection. Emotional processing tasks included those which have previously been shown to be sensitive to the effects of depression and antidepressant treatment, namely facial expression recognition, emotional categorisation and the dot probe attentional task. Following IFN-α, patients were more accurate at detecting facial expressions of disgust; they also showed diminished attentional vigilance to happy faces. IFN-α produced the expected increases in scores on depression rating scales, but there was no correlation between these scores and the changes in emotional processing. Our preliminary findings suggest that IFN-α treatment produces negative biases in emotional processing, and this effect is not simply a consequence of depression. It is possible that increased recognition of disgust may represent a neuropsychological marker of depressive disorders related to inflammation.
Highlights
Interferon-α (IFN-α) is an endogenous cytokine that, when given as an exogenous therapy, potently activates the pro-inflammatory cytokine network to produce antiviral and antiproliferative effects (Capuron & Miller, 2004)
It has been proposed that IFN-α-induced changes in tryptophan metabolism may lead to lowered brain serotonin levels and increased production of neurotoxic metabolites, such as quinolinic acid (Capuron et al 2002; Miller, 2009)
Correlations between psychological ratings and emotional processing tasks Depressed mood scores measured by the Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAM-D) either at baseline or at 6 weeks were not significantly correlated with emotional processing task performance in the current study, for example, depressed mood was not associated with disgust recognition
Summary
Interferon-α (IFN-α) is an endogenous cytokine that, when given as an exogenous therapy, potently activates the pro-inflammatory cytokine network to produce antiviral and antiproliferative effects (Capuron & Miller, 2004). The clinical observation that IFN-α is capable of inducing symptoms that are strikingly similar to major depression is important evidence for the proposed role of endogenous pro-inflammatory cytokines in the development of depressive states more generally (Raison et al 2006; Zunsain et al 2013). It has been proposed that IFN-α-induced changes in tryptophan metabolism may lead to lowered brain serotonin levels and increased production of neurotoxic metabolites, such as quinolinic acid (Capuron et al 2002; Miller, 2009). There is preliminary evidence from magnetic resonance spectroscopy that IFN-α-induced alterations in glutamine and glutamate levels in the anterior cingulate cortex may correlate with depressive symptomatology (Haroon et al 2014; Taylor et al 2014). Treatment of medical patients with the inflammatory cytokine, interferon-α (IFN-α), is frequently associated with the development of clinical depressive symptomatology. The aim of the present preliminary study was to assess the effect of IFN-α on measures of emotional processing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
