Substance use and hepatitis C: an ecological momentary assessment study.

Infection with hepatitis C virus (HCV) is a complex public health problem with a high prevalence of chronic infection, an increasing prevalence of HCV-associated disease, low rates of testing and treatment, and the prospect of increasing incidence associated with intravenous drug use (IVDU; Smith, Jorgensen, Zibbell, & Beckett, 2012). IVDU is a major risk factor for HCV, and HCV prevalence is exceedingly high among intravenous drug users (Schreuder et al., 2010). A study conducted in Baltimore, MD, found that the seroprevalence of HCV among intravenous drug users was 77%, with most individuals becoming positive within the first year of initiating IVDU (Garfein, Vlahov, Galai, Doherty, & Nelson, 1996). IVDU does not directly influence HCV progression despite the potential for multiple repeat exposures to various HCV genotypes, but HCV progression may be accelerated by several factors associated with IVDU, including excess alcohol intake, reduced access and adherence to treatment, and poor nutrition (Cooper & Mills, 2006). Given the adverse public health consequences of HCV infection and its link to HIV, improved approaches to reducing the spread of HCV, particularly among intravenous drug users, are needed. Although there is strong evidence that medication-assisted addiction treatment reduces drug misuse, HIV-risk behaviors, and HIV infection rates (Metzger, Woody, & O’Brien, 2010; Millson et al., 2007), the corresponding evidence for HCV remains controversial (Crofts, Nigro, Oman, Stevenson, & Sherman, 1997; Selvey, Denton, & Plant, 1997; Thiede, Hagan, & Murrill, 2000), suggesting that approaches beyond medication-assisted treatment alone are needed to curb HCV-risk behaviors and infection rates. Given that risk behaviors persist during addiction treatment (Chaudhry et al., 2011) and are more likely among patients who do not know their HCV status (Vidal-Trecan, Coste, Varescon-Pousson, Christoforov, & Boissonnas, 2000), one approach might be to test people for hepatitis C upon addiction-treatment admission and inform them of the results. Unawareness of HCV status is common. In one study, 72% of HCV+ and 46% of HCV− intravenous drug users were unaware of their HCV status (Hagan et al., 2006). However, even after diagnosis with HCV, high-risk behaviors continue (Hagan et al., 2006; Ompad, Fuller, Vlahov, Thomas, & Strathdee, 2002). The initial diagnosis of HCV had a strong, negative emotional effect in almost half of a patient group that was not primarily composed of intravenous drug users (Fabris et al., 2006). For intravenous drug users, an HCV diagnosis is sometimes thought to be less momentous than for nonintravenous drug users, but that may not always be true (Treloar & Rhodes, 2009). As for possible emotional effects of the disease process itself, there seems to be no published research; phenomenological studies of hepatitis C focus on patients who have begun antiviral treatment, which can produce psychiatric side effects of its own (Sgorbini, O’Brien, & Jackson, 2009). What is unknown is whether ongoing risk behavior is increased by the negative emotional effect of HCV diagnosis itself or by other factors in the lived experience of HCV+ individuals not on antiviral treatment. The analyses presented here are part of a project to better understand the factors influencing drug use and lapse and improve approaches to reducing high-risk behaviors. We have followed up on prior research in our laboratory showing that HCV+ patients in methadone maintenance report higher drug-related HIV-risk behaviors and are more likely to test positive for opioids compared with HCV− patients (Willner-Reid, Belendiuk, Epstein, Schmittner, & Preston, 2008). Our treatment-research clinic uses ecological momentary assessment (EMA), a technique for collection of in-the-field, first-person data using handheld computers. EMA largely eliminates recall bias by collecting self-report in near real time and produces time-stamped data that are amenable to statistical aggregation (Shiffman, Stone, & Hufford, 2008). We have previously reported success with EMA in a study of over 100 heroin- and cocaine-using methadone-maintained patients and shown that cocaine-use events are preceded by increasing exposure to drug-use triggers and are associated with craving, stress, and tobacco use (Epstein, Marrone, Heishman, Schmittner, & Preston, 2010; Epstein & Preston, 2010; Epstein et al., 2009; Preston et al., 2009). In the analyses reported here, we determine whether HCV+ and HCV− individuals are differentially exposed, in their daily lives, to triggers of craving and drug use, and we explore the relationship of HCV status with demographics and momentary moods in patients whose HCV is not yet overtly symptomatic in an effort to inform treatment interventions for reduction of HCV-risk behavior and infection rates.