Accounting for differences in risk of HCV re-infection by mental health diagnoses

ABSTRACT

Introduction: There is widespread concern regarding the potential for hepatitis C virus (HCV) reinfection among key populations, particularly among people who inject drugs (PWID) and those living with a mental health condition.

Area Covered: In this editorial we discuss the potential for specific mental health diagnoses (e.g., bipolar vs. substance use associated mania, vs. schizophrenia related disorders) to impact reinfection risk. This is an important consideration given distinct variations in risk behaviors for blood-borne virus infections (e.g., needle sharing) and patterns of health service use between diagnoses. Consideration of psychotropic agents may also have an effect on HCV reinfection given the supplemental influence of certain agents (e.g., typical antipsychotic drugs) on risk behaviours.

Expert Commentary: An improved understanding of these effects may foster the beginning of a new era in the response to the optimal delivery of harm reduction programs and HCV care among PWID and those living with a mental health condition.

KEYWORDS:

• Hepatitis C
• reinfection
• risk behaviors
• mental health diagnostic groups
• mental health stigma
• pharmacological agents

The advent of direct-acting antivirals (DAAs) for the treatment of hepatitis C virus (HCV) has revolutionized HCV treatment by offering a highly effective, well-tolerated, shorter course therapy. This provides a substantial opportunity to expand treatment, and to reduce HCV prevalence among various groups, including marginalized populations (e.g. people who inject drugs [PWID]) [1]. However, HCV reinfection is of significant concern among key populations, particularly among PWID and those living with a mental health condition [2–4]. A recent study modeled HCV reinfection risk among PWID and examined the role of opioid substitution therapy and mental health counseling on HCV reinfection [4]. The authors’ pursuit to determine the impact of engagement in mental health counseling services on reinfection using a large population-level administrative linked database is a unique contribution to the literature. Nevertheless, we argue that the study could be strengthened by including disorder-specific measures (e.g. bipolar vs. substance use associated mania, vs. schizophrenia-related disorders) when assessing mental health services, as the effects of mental health counseling on HCV reinfection may be specific to and vary between diagnoses. Consideration of pharmacological agents to treat mental health conditions may be warranted as well, as there is evidence to suggest that these agents may have varying impacts on impulsivity (i.e. inhibition of actions) and risk behaviors for blood-borne virus infections (e.g. needle sharing).

In recent years, we have seen consistent and high-quality evidence to suggest distinct variations in risk behaviors and patterns of health service use between mental health diagnostic groups. For example, Reddy LF, et al. (2014) found large differences in measures of risk behaviors between 142 individuals with schizophrenia and those with bipolar disorder [5]. Similarly, an Australian cross-sectional study (2004) involving 615 heroin users found a heterogeneous relationship between borderline personality disorders (BPD), antisocial personality disorder (ASPD) and five major domains of harm: suicide, overdose, needle sharing, drug use, and psychopathology. Interestingly, a strong relationship was observed between BPD and needle sharing, as compared to the ‘no diagnosis’ group in this domain. In contrast, there was no resemblance of a relationship between ASPD and needle sharing when compared to the ‘no diagnosis’ group [6]. While it remains to be explored, it may be that individuals with BPD are more vulnerable to HCV reinfection compared to individuals living with other mental health conditions.

Islam and colleagues (2017) examined the effect of frequency of engagement with mental health counseling on risk of HCV reinfection [4]. Findings showed that an increase in the number of visits was not significantly associated with a linear increase in the reduction of reinfection. A conclusion drawn from this analysis was that individuals who engaged in more counseling sessions per year were probably those who presented with much higher risk behaviors. While this explanation is plausible, it may also be important to consider the variations in patterns of health service use between mental health diagnostic groups. There is evidence to suggest that individuals with more severe mental disorders (e.g. schizophrenia and BPD) are less likely to access care and they are also less likely to attend follow-up visits [7,8]. A contributory factor could be the essence and consequence of mental illness-related stigma, which varies across diagnostic groups [8–10]. Interestingly, there is no clear evidence that internal or self-stigma varies between diagnostic groups for patients – likely because few studies have investigated the matter. However, evidence suggests a distinct variance in attitudes and a preference for social distance (an important dimension of stigma) across diagnostic groups among health care providers [8–11]. It is likely that lower rates of social desirability would impact negatively on access and adherence to mental health counseling. Through these pathways, HCV reinfection risk may differ across diagnostic groups by way of healthcare access and stigma. While beyond the scope of this work, the perceived stigma associated with obtaining care for a mental health condition is something that needs to be addressed.

Accumulating evidence also points toward the important role of pharmacological agents on impulsivity and risk behaviors as these agents have varied effects on numerous neurotransmitter receptors, including those for dopamine and serotonin, which are directly associated with risk behaviors [12,13]. For example, findings from a Canadian-based cross-sectional study revealed that among 70 out-patients meeting the DSM-IV criteria for schizophrenia, the mean impulsivity score of those treated with typical antipsychotic drugs was significantly higher than those treated with clozapine [13]. As a result, higher impulsivity may lead to an increased risk in HCV reinfection among people living with schizophrenia treated with these medications. Given that little is known on this topic, future studies should examine the impact of psychotropics on HCV reinfection risk.

In conclusion, we commend the authors for this pioneering work and appreciate that the underlying sub-factors outlined earlier may not have been considered because there was not sufficient power to detect meaningful differences. However, we argue that mental health conditions and pathways to disease risk are complex in nature. As such, the utility of these findings could be further enhanced if accompanied by empirical evidence which teases out distinct mental health diagnostic groups, and which takes into account pharmacological agents that may impact HCV reinfection risk.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This article was not funded.