Summary. Hepatitis C virus (HCV) is known to adversely affect general, social, emotional and mental health domains. This study was designed to identify variables that may be associated with these measurable outcomes. We conducted a cross-sectional retrospective review of demographic and clinical data from 800 patients with HCV evaluated between January 1998 and November 2007. Data were collected using a standardized questionnaire filled out by the patients at the first encounter. Variables evaluated included fibrosis stages (i.e. FS0/1/2 vs FS3/4), demographics, comorbid health conditions, tobacco and alcohol use, high-risk social behaviours and laboratory data. Variables assessed were depression, fatigue, problems sleeping and loss of interest in sex. Statistical analysis was performed using univariate and multivariate logistic regression. Depression (29.3%) in our HCV study population was associated with female gender, tobacco use, hyperlipidemia, history of heavy alcohol use and intravenous drug use. Fatigue (44.6%) was associated with end-stage renal disease, past and current tobacco use and current alcohol use. Difficulty sleeping (13.8%) was associated with past and current tobacco use, current alcohol use and diabetes. Loss of interest in sex (7.7%) was associated with current tobacco use, multiple risk factors for HCV and age at time of evaluation. Fibrosis stage (FS) also had a significant positive association with alcohol use (OR 2.61; P = 0.003) and tobacco use (OR 2.00; P = 0.002). Smoking and alcohol use have a significant negative impact on the presence of depression, fatigue, difficulty sleeping and loss of interest in sex in HCV patients. Practitioners should be aware of these associations, particularly tobacco use, which significantly and negatively impacted every variable evaluated.