HIV and hepatitis C prevention among people who inject drugs in Sweden : harm reduction policies, risk behaviour interventions and outcomes

Sammanfattning: People who inject drugs (PWID) is a heterogeneous and hard-to-reach group due to legal implications, stigma and discrimination. PWID are vulnerable to various poor health outcomes including HIV and hepatitis due to ongoing injection and sexual risk behaviours, various forms of abuse, poor health seeking behaviours, and limited access to- and retention in prevention and care programs. General knowledge about PWID, hepatitis C (HCV) and HIV-risks is good, but less is known about certain sub-populations such as women who inject drugs (WWID). In order to reach PWID with harm reduction, primarily to reduce their risk of HCV and HIV, countries have introduced needle exchange programs (NEP). However, low NEP-availability and insufficient awareness of gender-specific and other sub-group barriers and needs challenges the coverage, uptake and effectiveness of harm reduction for PWID. The overall aim of this thesis was to analyse NEP-development in Sweden and to study determinants for injection and sexual risk behaviours among PWID over time in Stockholm, Sweden. In paper I, NEP-development in Sweden was analysed over time (1985–2017) in relation to Swedish drug and health policy. We found that NEP-development was obstructed for a long period because of costly time- and resource-intensive obstacles and processes, e.g. a municipal veto towards starting NEP, involving actor-coalitions, absence of evidence and ideological and individual moral dimensions on both policy and implementation levels. With renewed focus on the individual drug user-perspective, accumulation of evidence, a NEP-law, changes in actor-coalitions and removal of the veto, Sweden saw a fast NEP-development. In paper II, determinants for risk behaviours among PWID (n=2,150) at enrolment in remand prisons were studied over time from 2002–2012. Female sex, homelessness, young age and amphetamine injection drug use (IDU) were determinants associated with high levels of injection risk behaviours. Further, injection risk behaviours decreased over time among new enrolled PWID in remand prisons. In paper III, determinants and injection risk behaviours at enrolment and over time (2013–2018) were studied among PWID (n=2,860) in the first NEP in Stockholm. An overall significant reduction in injection risk behaviours was found over time and in relation to most enrolment determinants. Female sex, homelessness and amphetamine use were determinants that correlated to an increased risk of sharing needle/syringes and paraphernalia at enrolment, whereas opioid substitution therapy (OST) appeared protective. In paper IV, subgroup determinants for injection and sexual risk behaviours and program retention were studied among WWID (n=697) in the Stockholm NEP (2013–2018). Homelessness, amphetamine-IDU, not being in OST and a history of being sectioned (i.e. psychiatric or addiction-related compulsory care) was associated with high injection risk behaviours. Younger age, stable civil status, not in OST and being HIVnegative were associated with higher sexual risk behaviour. WWID were more likely than men to remain in the NEP over time, and previously sectioned WWID were associated with risk for being LTFU. To conclude, our findings highlight the need to better understand the needs of various sub-groups of PWID to successfully tailor harm reduction interventions and scale-up NEP-programs to prevent the spread and eliminate HCV and HIV by 2030, as proposed by the WHO and UNAIDS.