Determinants of successful chronic hepatitis C case finding among patients receiving opioid maintenance treatment in a primary care setting

Abstract

Aims Injection drug users are at high risk for chronic hepatitis C virus infection (CHC). Opioid maintenance treatment (OMT) offers a unique opportunity to screen for CHC. This study proposed the hypothesis that a general practitioner (GP) with special interest in addiction medicine can achieve CHC screening rates comparable to specialized centres and aimed to investigate determinants for a successful CHC case finding in a primary care setting.Design and participants Retrospective medical record analysis of 387 patients who received opioid maintenance therapy between 1 January 2002 and 31 May 2008 in a general practice in Zurich, Switzerland.Measurements Successful CHC assessment was defined as performance of hepatitis C virus (HCV) serology with consecutive polymerase chain reaction‐based RNA and genotype recordings. The association between screening success and patient characteristics was assessed using multiple logistic regression.Findings Median (interquartile range) age and duration of OMT of the 387 (268 males) patients was 38.5 (33.6–44.5) years and 34 (11.3–68.0) months, respectively. Fourteen patients (3.6%) denied HCV testing and informed consent about screening was missing in 13 patients (3.4%). In 327 of 360 patients (90.8%) with informed consent a successful CHC assessment has been performed. Screening for HCV antibodies was positive in 136 cases (41.6%) and in 86 of them (63.2%) a CHC was present. The duration of OMT was an independent determinant of a successful CHC assessment.Conclusions In addicted patients a high CHC assessment rate in a primary care setting in Switzerland is feasible and opioid substitution provides an optimal framework.

Integrated internist – addiction medicine – hepatology model for hepatitis C management for individuals on methadone maintenance

“…Well‐structured MMTPs, with attributes such as access to mental health professionals and general medical staff, likely have advantages for HCV evaluation and treatment over those without such services. Consistent with the findings of prior studies [11,29], we found that men who were engaged in the MMTP for 36 months or more were significantly more likely to appear in the hepatitis clinic than those with shorter duration of opiate substitution therapy.…”

Patients receiving opioid maintenance treatment in primary care: successful chronic hepatitis C care in a real world setting

“…OR 1.02 37 months =2.0) of getting started CHC treatment compared to a patient simply fulfilling the inclusion criteria of minimum 3 months on substitution. This beneficial effect of OMT has already been shown to increase adherence and virological success in HIV treatment [16,18] and is in line with the finding that an ongoing OMT significantly increased the chance of a successful CHC case finding [19]. We are not aware of a study that has assessed the specific role of an OMT programme in the context of CHC treatment initiation.…”

“…A detailed description of the study population and the setting has been previously reported elsewhere [19]. Briefly, all patients ≥ 18 years old and participating for at least 3 months in an official office-based OMT programme run by a single-handed general practice located in Zurich, Switzerland were eligible for CHC assessment and evaluation for antiviral therapy in the case of a CHC infection.…”

“…On the other hand opioid maintenance treatment (OMT) is established in the therapy of substance abuse [16] and has been shown to be an effective framework for adherence and virological success in HIV treatment [17,18]. In addition we previously demonstrated the beneficial role of a substitution treatment as a therapeutic framework for a successful CHC case finding [19]. We hypothesized that a general practitioner (GP) providing an integrated chronic care approach including an OMT can achieve similar CHC treatment rates and viral eradication rates compared to patients without drug dependency.…”

Commentary on Senn et al. (2009): Primary care is the place to manage hepatitis C in opiate‐dependent patients

“…Senn and colleagues provide an encouraging offer of a successful model for the first stage of the process of identifying those at risk, diagnosing the presence of the disorder and starting treatment. They show clearly the value of opiate substitute treatment in engaging this risk group and the association of this therapy with a successful outcome in testing [7]. This experience of using the attraction of this treatment to encourage a wider health care agenda is not new, and some feel that it is coercive, but as with other harm reduction measures the end undoubtedly justifies the means.…”