Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in a Northern Alberta population

To describe the demographics and estimate the prevalence of hepatitis C virus (HCV) in a cohort of Human Immunodeficiency Virus (HIV) positive patients in Northern Alberta.

A cross-sectional (prevalence) study was performed on a cohort of HIV-positive patients. HCV testing was not widely available until December 1989, and the more sensitive, second generation immunoassay was not available until 1992. To reduce the effect of testing bias, we restricted consideration of HCV status to patients first seen January 1, 1992 onward.

Forty-four percent of patients in the whole cohort were tested for HCV (564/1,276) and 62% (505/809) of patients entered since January 1, 1992 were tested for HCV. During the period January 1, 1992-December 31, 1999, the prevalence of HCV in our cohort of northern Alberta HIV-positive patients was at least 37.9% (307/809) and was 60.8% (307/505) among those who were tested for HCV in 1992 or later. The mean age of the co-infected group was 33.6 years, 66.1% were male, 91.2% were injection drug users (IDUs), 56.8% were Caucasian, and 40.0% were Aboriginal. A statistically significant difference was found between the HCV-negative cohort, the HCV co-infected cohort, and the HCV-untested cohort for the following variables: risk behaviour, gender, ethnic status, death, occurrence of an AIDS-defining illness (p < 00.0001), and mean baseline CD4 cell count (p = 0.002).

A high proportion of the HIV-infected IDUs was co-infected with HCV. Compared to the HCV-negative group, the co-infected group appears to have had less advanced HIV disease. This is likely a reflection of more recent HIV infection in the HCV co-infected group.