Description: People with hepatitis C infection risk heart disease, a Japanese study suggests. Many different kinds of infections seem to increase the risk of heart disease. Why this happens isn't clear. The whole issue is still controversial. University of Tokyo researcher Nobukazu Ishizaka, MD, and co-workers looked at the general health screening tests from 4,784 people. Blood tests showed that 104 of these people carried the hepatitis C virus (HCV).