September 6, 2012
The study, which began enrollment in August 1990, included 738 volunteer blood donors who tested positive for hepatitis C antibodies. Confirmation testing was done using third-generation recombinant immunoblot assays (RIBA). The donors were interviewed by a physician about their histories, including illicit drug use. Liver biopsy specimens were taken from 185 patients with RIBA-confirmed hepatitis C.
Among the 738 volunteers, 469 had hepatitis C confirmed using RIBA. On multivariate analysis, the most significant risk factor was injection drug use, with an OR of 35 (95% CI, 10.4-218), followed by receiving a blood transfusion before 1991, with an OR of 9.9 (95% CI, 5.6-18.3). Intranasal cocaine use was also a significant risk factor, with an OR of 6.4 (95% CI, 3.8-11.2). In a subset of intranasal cocaine users who denied injection drug use and blood transfusion, the OR was 8.5 (95% CI, 4.9-15.1).
Among those who were confirmed with RIBA, 384 had hepatitis C virus RNA. From these patients, 33% of liver biopsy specimens showed no fibrosis, 52% had mild fibrosis, 12% had bridging fibrosis and 2% had cirrhosis.
“Identification of silent HCV carriers and access to treatment remain major public health hurdles, but among treated subjects, the number who will not achieve a sustained virologic response has been reduced dramatically with the recent licensure of protease inhibitors,” the researchers wrote. “Since the majority of HCV-infected individuals will not be treated in the near term, continued long-term follow-up is critically needed to provide better estimates of clinical and histologic outcomes after 3 or more decades of HCV infection."
Disclosure: The researchers report no relevant financial disclosures.