Prevalence and distribution of hepatitis C subtypes in patients with opioid dependence

AIM AND SETTING: The drug addiction out-patient clinic at the University Hospital for Psychiatry in Vienna performed a study to identify the prevalence of hepatitis C virus (HCV) infections in a group of opiate-dependent patients, to detect the distribution of HCV subtypes and to calculate the comorbidity of human immunodeficiency virus (HIV) and hepatitis B virus (HBV).

We consecutively investigated unselected patients (n = 173) during an observation period of 2 months with the diagnosis of opioid dependence (DSM-IV: 304.0) and polysubstance dependence (DSM-IV: 304.9).

Blood was investigated focusing on liver enzymes and on viral status including HIV, hepatitis B and hepatitis C, followed by subtyping of the virus.

In 80.3% hepatitis C antibodies were found, 66.5% were HCV RNA (PCR) positive. 3a was the most frequent subtype (35.6%), followed by 1a (28.8%) and 1b (22.0%). Four patients had both subtypes 1a and 1b (6.8%), 3 were 2b positive (5.1%) and 1 patient had subtypes 2a/2c (1.7%). No significant difference in aspartate (AST) and alanine aminotransferases (ALT) concerning the different subtypes (AST: p = 0.290; ALT: p = 0.260) could be calculated; 11.6% showed co-infection with HIV, 2 patients had a chronic infection with hepatitis B.

The rate of HCV infection in substance-dependent patients at our drug addiction out-patient clinic is extremely high. The distribution of subtypes showed a relatively homogeneous distribution of the types 1a, 1b and 3a. The recommended therapy with alpha-interferon should be initiated in drug-dependent patients under considerations of an enrollment in oral maintenance with synthetic opioids.