Hepatitis C and substance use in a sample of homeless people in New York City.

This study examined the prevalence of hepatitis C virus (HCV) antibodies and its association with substance use and sexual behavior among a sample of 139 persons visiting a mobile medical clinic in Manhattan. Ninety percent were unstably housed or were living on the street. The prevalence of HCV antibodies was 32%. Prevalence was also high for hepatitis B core antibodies (47%), HIV antibodies (15%), and syphilis exposure (14%); 76% tested positive for cocaine. Among subjects who reported ever injecting (20%), 86% were HCV positive; 19% of non-injectors were HCV positive. In separate multivariate logistic regression models (with injection controlled), HCV was predicted by quantitative hair assays for cocaine and self-reported duration of crack-cocaine use. Alcohol dependence and sexual behavior did not predict HCV. Hepatitis C is a significant public health problem among the urban homeless population, with injection drug use and, to a lesser extent, cocaine use implicated as risk factors.