People who inject
drugs (PWID) recently released from prison or jail have a substantially
increased risk of acquiring infection with HIV or hepatitis C virus (HCV), according to the results
of a systematic review and meta-analysis published in The Lancet Infectious Diseases. Recent incarceration was associated with an 81% increase in the risk of
HIV and 62% increase in the risk of hepatitis C.
“Our findings suggest that incarceration
is an important enhancer of HIV and HCV acquisition risk among PWID
globally,” comment the authors. They believe their findings have
important policy implications, especially the
decriminalisation of illicit drug use. They also believe new
interventions are needed to minimise HIV and HCV risk among PWID,
including better linkage of people recently released from prison to harm
reduction and
opioid substitution services.
It has been estimated that 58% of PWID will experience incarceration.
The period immediately following release from incarceration is believed
to be a time of high risk for HIV and HCV transmission as well as
opioid-related overdose, due to relapse to drug use after release.
Several studies have suggested
that incarceration of PWID could be an important contributor to the
ongoing
epidemics of HIV and HCV among this population, but the extent
of the association between incarceration and HIV and HCV acquisition
among PWID
is poorly understood. This prompted an international team of
investigators to
conduct a systematic review and meta-analysis of research addressing
this
question.
The researchers
identified 41 studies (21 unpublished) addressing this question. All were
conducted between 2000 and 2017. Study locations were Australia, Canada, Czech
Republic, France, Greece, India, Ireland, Mexico, Spain, Thailand, UK and USA.
Recent
incarceration was defined as release from prison or jail in the past three, six,
or 12 months or since last follow-up. Data were also examined on the impact
on past incarceration and risk of HIV and HCV acquisition.
A total of 14
studies reported on the effect of recent
incarceration on HIV acquisition risk. The pooled results showed that recent
incarceration was associated with an 81% increase in HIV acquisition risks (RR
= 1.81; 95% CI, 1.40-2.34, p < 0.001). Recent incarceration continued to be
associated with increased HIV risk after controlling for potential confounders
(RR = 1.48; 95% CI, 1.16-1.90, p = 0.002) and also in studies assessed to have
a low-to-moderate risk of bias (RR = 1.65; 95% CI, 1.26-2.16, p = 0.006).
A further 12 studies reported in the impact of past incarceration and HIV acquisition,
showing a non-significant 25% increase in risk (RR = 1.25; 95% CI, 0.94-1.65).
The effect of
recent or past incarceration on HIV acquisition risk did not differ by
geographical region or country income level. The effect of incarceration was greater
among younger than older participants.
The effect of
recent incarceration on HCV acquisition risk was assessed in 18 studies. These
showed that recent incarceration was associated with a 62% increase in the risk
of acquiring HCV infection (RR = 1.62; 95% CI, 1.28-2.05, p < 0.001). The
finding was essentially unchanged after controlling for confounders (RR = 1.60;
95% CI, 1.21-2.11, p < 0.009).
The impact of past
incarceration on HCV acquisition was examined in 22 studies, showing a
significant 21% increase in risk (RR = 1.21; 95% CI, 1.02-1.43, p = 0.027).
However, this finding was not significant after controlling for confounders; nor
was there a significant association in studies rated as having low-to-moderate
risk of bias.
As with HIV, the
association between incarceration and increased HCV acquisition risk did not
differ between geographical region or country income level. However, there was a
greater effect in countries with higher rates of incarceration.
“To our knowledge,
this study is the first to have quantitatively synthesised available evidence
on the effect of incarceration on HIV and HCV acquisition risk among PWID,”
write the authors.
“Our findings are consistent with studies that find that
incarceration is associated with relapse to injecting drug use and that
recently incarcerated PWID exhibit increased injecting risk behaviour and
reduced access to harm reduction interventions compared with PWID who do not
report recent incarceration.”
The authors
believe their findings have several important implications for public health
and international drug policies:
- Current international policy
has a punitive approach to PWID, leading to high rates of incarceration.
- A need for improved prison-based
harm reduction, which is absent in most countries and often inadequate even
when available.
- A requirement for improved
linkage on release from incarceration to harm reduction and other services to
address the numerous social vulnerabilities, especially homelessness, that are
increased for PWID on release from incarceration.
“Our findings add to the growing body of evidence for the harms
associated with international drug policy, which result in many people who use
drugs being incarcerated, and support calls for decriminalisation of illicit
drug use and greater access to prison-based harm reduction, with linkage
following release," comment the authors. "However, it is likely that addressing many of the multiple
social vulnerabilities experienced by PWID will also be required to fully
reduce the risks associated with incarceration.”