Prevalence of Risk Factors for Hepatitis C Virus in HIV-Infected and HIV/Hepatitis C Virus-Coinfected Patients SRIGAYATRI BOLLEPALLI, MD,* KATHLEEN MATHIESON, PHD,* CURT BAY, PHD,* AMY HILLIER, PAC,* JOHN POST, MD,* DAVID H. VAN THIEL, MD,† AND ABDUL NADIR, MD* Methods: A sample of patients with HIV completed a questionnaire identifying their demographic characteristics and risk factors for hep- atitis C virus (HCV). A chart review was conducted to confirm the information obtained using the questionnaire. Risk factors associated with coinfection status at  level of 0.1 in univariate analysis were entered into a multivariate Cox regression model. Results: Of the 242 HIV-positive patients analyzed, 168 were HIV- infected and 74 were HIV/HCV-coinfected. Risk factors that were significantly different between HIV-monoinfected and HIV/HCV-coin- fected subjects included intravenous drug use, snorting drugs, sharing razors or toothbrushes, being in prison, the presence of one or more tattoos, sex for money or drugs, sex with an intravenous drug user and man who has sex with men. In a multivariate regression model, only intravenous drug use remained as a significant risk factor/predictor of HCV/HIV coinfection. A subanalysis identified risk factors more prev- alent among coinfected men who have sex with men, including intra- venous drug use, sharing razors/toothbrushes, tattoos, sex for money or drugs, sex with an intravenous drug user, and a history of having 11 or more sexual partners. A history of having had a sexually transmit- ted disease and 11 or more sex partners was more prevalent among HIV-monoinfected men who have sex with men. Conclusions: HIV/HCV coinfection was associated with intrave- nous drug use but not with sexual risk factors. SEXUAL TRANSMISSION OF HEPATITIS C virus (HCV) has remained a subject of controversy. The prevalence of HCV is much higher in HIV-infected individuals in contrast to the preva- lence of HIV in HCV-infected individuals. These observations can be explained in part as a result of a predominant role for sexual transmission of HIV and a parenteral route for HCV transmission. 1 Recently, outbreaks of acute HCV have been reported in highly promiscuous men who have sex with men (MSM) in Europe. Investigators from a Swiss cohort reported 22 episodes of acute HCV in 14 homosexual and 8 heterosexual men (P 0.001) who had previously tested negative for HCV. In Paris, 10 of 12 cases of genotype 4D HCV infection having a closely related HCV genome were identified in homosexual MSM. 2–5 One study reported a higher prevalence of HCV among MSM as compared with a group of blood donors. A multivariate analysis showed that this finding could be accounted for by a history of intravenous drug use (IVDU). 6 Although these reports are tantalizing, sequence homology of HCV clones has its own limitations and does not definitively confirm transmission of HCV from one individual to another. 7 In contrast to these recent reports, many epidemiologic studies have failed to show an association between sexual risk factors and HCV infection. Heterosexual monogamous couples who have been followed prospectively have failed to support sexual transmission of HCV. 8 In addition, the prevalence of HCV among MSM has not been found to be different from that of heterosexual men despite the fact that MSM have higher rates of sexually transmitted dis- eases and more numerous sexual partners. 9 Finally, a prospective cohort study of MSM (40.3% having 50 casual partners) docu- mented a strong association between HCV infection and IVDU, but not between HCV and sexual orientation. 10 The epidemiologic surveys used in many studies presume that the information obtained from a subject using a questionnaire is accurate. Specifically for HCV transmission, nondisclosure of IVDU by study participants would certainly invalidate the results of any such survey. 11 To achieve meaningful data from an epidemiologic survey regarding HCV transmission, all recognized risk factors for HCV transmission (e.g., tattoos, snorting nasal cocaine, birth in underde- veloped countries, hemodialysis, sharing of household items, being in prison, and sexual factors) must be considered. 12–14 The current study sought to identify sexual and other risk factors that distinguish be- tween HIV-monoinfected and HCV/HIV-coinfected individuals. Methods This was a cross-sectional study conducted from January 28, 2005, to May 13, 2005. Patients were selected by convenience sampling from 2 urban clinics catering specifically to patients who are HIV-infected and those with liver disease in Phoenix, Arizona. A trained physician researcher attended the HIV and liver disease clinics 3 times a week throughout the study period, approached potential subjects in the waiting room at each location, and told prospective subjects the study was designed to identify risk factors for HCV transmission in an HIV-infected population. Each poten- tial subject was told that their involvement in the study would consist of the completion of a self-administered survey that would take 5 to 10 minutes and that the researchers would have access to their medical records, but their personal information would be kept confidential. A total of 360 patients were approached, and 316 (88%) agreed to participate. The questionnaires were administered in both English and Span- ish depending on the subject’s preference and included questions Correspondence: Abdul Nadir, MD, 2601 E. Roosevelt Street, Phoenix, AZ 85008. E-mail: anadir786@aol.com. Received for publication March 26, 2006, and accepted July 25, 2006. From *Maricopa Medical Center (MMC) Phoenix, Arizona; and †St. Luke’s Hospital, Milwaukee, Wisconsin Sexually Transmitted Diseases, June 2007, Vol. 34, No. 6, p.367–370 DOI: 10.1097/01.olq.0000240295.35457.b1 Copyright © 2007, American Sexually Transmitted Diseases Association All rights reserved. 367