NYU Langone Medical Center, New York, NY.
Although injection drug use (IDU) and blood transfusions prior to 1992 are well-accepted risk factors for hepatitis C virus (HCV) infection, many prior studies that have evaluated tattooing as a risk factor for HCV infection did not control for a history of IDU or transfusion prior to 1992. In this large, multicenter case-control study we analyzed demographic and HCV risk factor exposure history data from 3,871 patients, including 1,930 with chronic HCV infection (HCV RNA positive) and 1,941 HCV negative (HCV antibody negative) controls. Crude and fully adjusted odds ratios of tattoo exposure by multivariate logistic regression in HCV infected versus controls were determined. As expected, injection drug use (65.9% vs. 17.8%, p < 0.001), blood transfusions prior to 1992 (22.3% vs. 11.1%, p < 0.001), and history of having one or more tattoos (OR = 3.81; 95% CI 3.23 - 4.49, p<0.001) were more common in HCV-infected patients than in control subjects. After excluding all patients with a history of ever injecting drugs and those who had a blood transfusion prior to 1992, a total of 1,886 subjects remained for analysis (465 HCV positive and 1,421 controls). Among these individuals without traditional risk factors, HCV positive patients remained significantly more likely to have a history of one or more tattoos after adjustment for age, sex, and race/ethnicity (OR = 5.17; 95% CI 3.75 - 7.11, p<0.001). Conclusion: Tattooing is associated with HCV infection, even among those without traditional HCV risk factors such as injection drug use and blood transfusion prior to 1992.