Chronic hepatitis C in Austria, 1992-2006: genotype distribution and demographic factors.

Chronic hepatitis C is a leading cause of end-stage liver disease and, with a worldwide prevalence of up to 3%, is a pandemic infectious disease. Austria, like most western European countries can be considered as a low prevalence country. This analysis aimed to assess the distribution of hepatitis C virus (HCV) genotypes in patients with chronic HCV infection in Upper Austria. Between September 1992 and December 2006, we identified 1,318 consecutive patients who tested positive for HCV RNA. Genotyping was routinely performed in 1,239 of the 1,318 patients, and in a subgroup of 617 patients data on the source of transmission were collected. Additionally we obtained data on liver histology and body mass index in a subsample of 273 of the 617 patients. Hepatitis C genotypes 1, 2, 3, 4, 6 and co-infections were found in 80.4%, 4.5%, 12.3%, 2.7%, 0.1% and 0.2% of the patients, respectively. There was a highly significant age difference in relation to gender at the time of diagnosis of chronic hepatitis C, with women being older than men (men: 45.0 years; women: 49.3 years; p<0.0001). The number of new cases of chronic hepatitis C decreased substantially over the last decade, but although risk factors for obtaining HCV are well established, we did not find a decrease in the age of first diagnosis. Besides consistent screening in defined risk groups it is important to raise awareness for risk factors for HCV acquisition and liver disease progression.