Self-Harm Among Forensic Psychiatric Inpatients With Schizophrenia Spectrum Disorders: An Explorative Analysis

• Author: Johannes René Kappes,David Alen Huber,Johannes Kirchebner,Martina Sonnweber,Moritz Philipp Günther,Steffen Lau
• DOI: http://doi.org/10.1177/0306624X211062139
• Published date: 01 March 2023
• Date: 01 March 2023
• Subject Matter: Articles

https://doi.org/10.1177/0306624X211062139

International Journal of

Offender Therapy and

Comparative Criminology

2023, Vol. 67(4) 352 –372

© The Author(s) 2021

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DOI: 10.1177/0306624X211062139

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Article

Self-Harm Among Forensic

Psychiatric Inpatients With

Schizophrenia Spectrum

Disorders: An Explorative

Analysis

Johannes René Kappes1,* , David Alen Huber1,*,

Johannes Kirchebner1, Martina Sonnweber2,

Moritz Philipp Günther2, and Steffen Lau1

Abstract

The burden of self-injury among offenders undergoing inpatient treatment in forensic

psychiatry is substantial. This exploratory study aims to add to the previously

sparse literature on the correlates of self-injury in inpatient forensic patients with

schizophrenia spectrum disorders (SSD). Employing a sample of 356 inpatients with

SSD treated in a Swiss forensic psychiatry hospital, patient data on 512 potential

predictor variables were retrospectively collected via file analysis. The dataset was

examined using supervised machine learning to distinguish between patients who

had engaged in self-injurious behavior during forensic hospitalization and those

who had not. Based on a combination of ten variables, including psychiatric history,

criminal history, psychopathology, and pharmacotherapy, the final machine learning

model was able to discriminate between self-injury and no self-injury with a balanced

accuracy of 68% and a predictive power of AUC = 71%. Results suggest that forensic

psychiatric patients with SSD who self-injured were younger both at the time of

onset and at the time of first entry into the federal criminal record. They exhibited

more severe psychopathological symptoms at the time of admission, including higher

levels of depression and anxiety and greater difficulty with abstract reasoning. Of

all the predictors identified, symptoms of depression and anxiety may be the most

promising treatment targets for the prevention of self-injury in inpatient forensic

1Psychiatric University Hospital Zurich, Switzerland

2University of Zurich, Switzerland

*Shared co-first authorship.

Corresponding Author:

Johannes René Kappes, Department of Forensic Psychiatry, Psychiatric University Hospital Zurich,

Lenggstrasse 31, Zurich8032, Switzerland.

Email: Johannes.Kappes@pukzh.ch

1062139IJOXXX10.1177/0306624X211062139International Journal of Offender Therapy and Comparative CriminologyKappes et al.

research-article2021

Kappes et al. 353

patients with SSD due to their modifiability and should be further substantiated in

future studies.

Keywords

schizophrenia, offending, self-harm, machine learning, forensic psychiatry

Introduction

Beyond being physically detrimental, self-harm constitutes a predictor of poor mental

health and suicide that is increasingly recognized as an emerging public health prob-

lem (Borschmann et al., 2017, 2018; Haw et al., 2001; Klonsky et al., 2014; McManus

et al., 2019; Olfson et al., 2018; Tsiachristas et al., 2020). Self-harm rates are particu-

larly high in prison or forensic psychiatric contexts among individuals convicted for

violent offenses and with a history of psychiatric disorders and treatment, as well as a

history of alcohol and/or drug dependence. Other risk factors include poor coping and

problem-solving skills, a history of self-harm, relationships with someone who also

engages in self-harm, and high levels of aggression, impulsivity, anxiety, and depres-

sion (Crighton & Towl, 2002; Marzano, 2010).

Self-harm can serve different functions, the most common of which is coping with

negative emotions (Klonsky et al., 2014; McManus et al., 2019). In prisoners, manipu-

lative intent does not exclude the risk of severe or even lethal self-harm: Between 24%

and 50% of all self-inflicted injuries in prison settings are believed to be conducted for

instrumental purposes (e.g., attention seeking, to intimidate staff or other inpatients)

and are further enhanced by receiving attention and support (Jeglic et al., 2005;

Marzano, 2010). However, manipulative intent does not exclude the risk of severe or

even lethal self-harm (Dear et al., 2000) and labeling self-harm as “manipulative” can

therefore be an oversimplification of what is in reality a more complex and often

severe phenomenon, risking inappropriate treatment (Lanes, 2011; Smith, 2015; Smith

et al., 2019). Within the forensic psychiatric context, it is important to assess whether

there is a secondary gain (e.g., attention, sedating medication, etc.) that results from

self-harm. In many cases, individuals with actual psychotic disorders do not derive

any benefit from engaging in this behavior, but rather act on perceived commanding

voices or injure themselves to silence the voices (Jeglic et al., 2005). Individuals with

schizophrenia spectrum disorders (SSD) are at high risk for self-harm, with a lifetime

prevalence ranging from 49% to 68% (Mork et al., 2012; Pluck et al., 2013; Singhal

et al., 2014). To successfully treat self-harm in people with SSD, identifying the mech-

anisms that perpetuate the behavior is therefore essential. It may also be worth identi-

fying subpopulations among patients with SSD and subgroup-specific risk factors for

self-harm (Haddock et al., 2013; Harvey et al., 2008), which could be useful in devel-

oping specific intervention and prevention strategies. So far, few existing interven-

tions for self-harm have received empirical support, and no treatments have been

developed that specifically target self-harm, particularly in the forensic psychiatric

setting (Dixon-Gordon et al., 2012).