ABSTRACT
OBJECTIVE: The aim of this study is to investigate the development of depression during interferon-alpha (IFN-α) therapy and the variations in the expression of the serotonin receptor (5-HTR) and transporter (5-HTT) in hepatitis C patients. METHOD: Hepatitis C patients (n=277) were given the Mini International Neuropsychiatric Interview at the end of IFN-α therapy. Three polymorphisms were genotyped: the serotonin transporter repeat length polymorphic region [5-HTT gene-linked polymorphic region (5-HTTLPR)], as well as SNPs rs25531 and rs6295, located within the 5-HTTLPR and the transcriptional control region of the 5-HTR1A gene, respectively. RESULTS: The diagnosis of current depression, which was associated with IFN-α-related depression (P<.001), demonstrated a statistically significant association with the CC genotype of the 5-HTR1A gene (odds ratio=5.57, 95% confidence interval=1.61-19.24, P=.007). CONCLUSIONS: Persistent depression may represent a more specific type of IFN-α-related psychopathology. Future studies need to investigate the genetic risk factors for vulnerability associated with persistent depression. Limitations, such as the study's cross-sectional design, small sample size and retrospective assessment of IFN-α-induced depression diagnosis, must be taken into account while interpreting the results found in this study.