Abstract

Background and aims: New Psychoactive Substances (NPS) have affected prison populations,
threatening the safety of prisoners and staff. We investigated the prevalence of substance use
within a prison in the United Kingdom, focusing on NPS and its links with violence and
impulsivity.
Method: Cross-sectional questionnaire of 158 male category C prisoners with a mean age of
34.82 years (SD = 8.78). During their current sentence, 23% reported NPS use (NPS), 11%
“traditional substances” (TD), 23% both, and 43% no substance use (ND). Lifetime use was
reported as 62% NPS, 20% TD, and 18% ND.
Findings: More participants used NPS exclusively than participants using TD exclusively,
although the definition of NPS is problematic. The odds of violence against other prisoners, staff,
and property were higher for NPS users and they were more likely to be impulsive compared to
other groups. However, there was no significant interaction between NPS use and impulsivity in
participation in violent acts.
Conclusion: NPS use is a complex term and is prevalent in the prison, impacting on levels of
violence and influenced by impulsivity. The findings emphasise the need for tailored treatment
and prevention initiatives for NPS users.