A Multicenter Case-Control Study
            Hepatology. 2013 Jun;57(6):2117-23
            Carney K, Dhalla S, Aytaman A, Tenner CT, Francois F.
            http://www.ncbi.nlm.nih.gov/pubmed/23315899

Although injection drug use (IDU) and blood transfusions prior to 1992 are well-accepted
risk factors for hepatitis C virus (HCV) infection, many studies that 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 (ORs) of tattoo exposure by multivariate logistic
regression in HCV-infected versus controls were determined. As expected, IDU (65.9%
versus 17.8%; P < 0.001), blood transfusion prior to 1992 (22.3% versus 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
patients 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 IDU and blood transfusion prior to 1992.