Moreover, genetic variations of phospholipase A2 (PLA2) and cyclooxygenase-2 (COX2), the two key enzymes of the polyunsaturated fatty acid (PUFA) metabolism and prostaglandin learn more E2 (PGE2) synthesis, have also increased the risk of IFN-α-induced depression in a recent study (Su et al., 2010). Nevertheless, a number of relevant clinical findings pertaining to the Brazilian sample should be noted. Importantly, regarding the natural course of this substance-related depression, our study raises questions related to the possibility of psychic consequences to IFN-α administration lasting many years after the therapy cessation. In fact, only 4 of the 13 patients who were depressed at the evaluation did not meet criteria

for IFN-α-related major depression. Usually known to be limited to the regular 6 to 12 months of treatment (Capuron et al., 2002), this adverse effect may impose persistent psychopathology on at least 15% (9 out of

59) of the depressed patients up to 2 years after antiviral therapy termination. Therefore, we have recently hypothesized that, in some vulnerable patients, IFN-α may trigger a buy 3-Methyladenine pathophysiological pathway which may become autonomous and maintain the depressive symptoms, even in the absence of the exogenous cytokine, generating a chronic depressive episode (Galvão-de Almeida et al., 2010b). Concerning the relevant association of this adverse effect and the diagnosis of current anxiety disorder, we speculate that since depression and anxiety have been proposed as parts of the same psychopathological spectrum (Gorman, 1996–1997 and Nestadt et al., 2003), the latter may represent sequelae of IFN-α-triggered depression (Bonaccorso et al., 2001). Another explanation is that this comorbidity reveals an artifact of the current nosological classifications, and consequently of the diagnostic instrument Casein kinase 1 that was applied. The main limitation of our study is that these patients were not evaluated before the antiviral therapy. Consequently, although patients previously diagnosed with

a mood disorder have been excluded, we cannot affirm that the depressive symptoms began only after cytokine initiation. In order to contemplate this limitation, we have chosen to use the term “IFN-α-related depression”, rather than “IFN-α-induced depression”. Moreover, it should also be noted that a placebo or a control group of IFN-α-naïve HCV patients was not included to assure that diagnosed major depression episodes were really a consequence of the cytokine exposure, and not only part of the natural course of chronic hepatitis C. In addition, it is possible that the relatively low number of patients found to be diagnosed with depression during antiviral therapy (Capuron et al., 2002 and Asnis et al., 2003) may be a result of memory bias. In fact, the variable Time since Therapy Termination showed an association trend with the main outcome (p = 0.