Inmates sentenced to preventive detention are amongst the most violent in the Norwegian prison system. This study documents the self-reported history of substance abuse and mental health status based on multiple psychometric tests. Affective conditions are associated with an enhanced risk for prison violence and recidivism [
9], while alcoholism is frequently found among prisoners [
11]. This study confirms relatively high rates of mood disorders and alcoholism/drug-dependence in this population, underscoring the need for better rehabilitation strategies that include treatments for these psychiatric disorders.
The present results found a slight increase in symptoms compared to Kjelsberg et al. [
2] who found that 25% of the inmates had clinical anxiety and 38% had some degree of clinical depression. However, there was no information given on how the diagnoses were made or the severity of symptoms [
2]. Furthermore, the data obtained by Kjelsberg et al. [
2] were collected during the inmates' first week of imprisonment by prison employees not formally trained in mental health care [
2]. In the present study, we used face-to-face interviews and several well-validated tests for depression and anxiety. In addition, the length of time each prisoner had served was different, and this factor may have contributed to the differences observed between the two studies. Other factors that may have contributed to the current prevalence of mild depression and anxiety, apart from the obvious impact of imprisonment itself, e.g caffeine and smoking, is a matter of speculation. The scant previous literature gives contradictory results both regarding depression and the potential influence of caffeine intake [
19,
20] and for depression and the possible negative effects of smoking [
21-
23].
Both pharmaceutical compounds and drugs of abuse may induce depression and anxiety as side effects. During the interviews with the inmates, no access to information regarding their use of medications was given. Thus, the reported use of drugs as "psychotropic medication" in this study (table ) is entirely based on self-report. Some inmates could not remember the name, the dosage, or the treatment duration. In most cases however, they knew why the drug had been prescribed. The prisoners were also asked if they used legal drugs inappropriately and whether they used illegal substances. This was denied by all except for two prisoners who confirmed that they had tried illegal drugs for the first time during their current imprisonment. Thus, there is reason to suspect that illegal drugs are available within the high security facility.
Mental disorders and substance abuse are risk factors for increased criminal recidivism, particularly for violent and sexual offences [
24,
25]. Few studies have examined temperament and character traits as possible predictors for anxiety and depression. A study addressing this issue [
24] found a relationship between temperament, depression, and anxiety using the Temperament Character Inventory (TCI) [
26]. The TCI was also found useful in identifying prisoners with a history of substance abuse [
24]. Prisoners who had injected drugs during the past 12 months scored higher on the Novelty Seeking (NS) and Harm Avoidance (HA) scales, and lower on Persistence (PS), Self-directedness (SD), and Cooperativeness (CO) scales than non-injectors [
24]. Studies using Cloninger's character traits [
27,
28] have found a positive correlation between the severity of substance abuse and character traits manifesting immaturity, self-destructiveness, irresponsibility, and an inability to define or pursue meaningful goals (SD). Likewise, inmates with a severe substance abuse problem were less likely to be cooperative, empathic, compassionate, helpful, or to focus on the needs of others (CO). In contrast, the more severe the substance use, the more likely the inmates were to show a greater intrinsic desire for self-actualization, creativity, and spirituality (ST) [
26,
27].
In Ila prison's rehabilitation programs, the inmates are offered mental health services either in the form of group therapy or as individual consultations. A study [
6] that focused on the inmates' expectations of gain from the different programs provided by the criminal justice system found that 58% had negative experiences. The main criticism was that the programs were not sufficiently targeted towards each individual's needs and that the prison staff leading the various program sessions did not possess the necessary competence. Therefore, it is possible that some inmates, given their lack of thrust in the services offered [
6], underreported their symptoms.
Table shows the distribution of substance abuse in subgroups of inmates based on the offences committed. The number of inmates on preventive detention with a history of substance abuse (18/26) was approximately 70%, consistent with previous studies showing that the effects of alcohol are significantly associated with incarceration for violent crime [
29]. There is also evidence linking alcohol use or abuse with aggressive sex crimes, that the role of alcohol consumption seems to be greater in sexual offenders targeting boys than in those targeting girls, and that substance abuse contributed to recidivism [
30]. A study from New Zealand [
31] found that 81% of male prisoners in a medium/minimum security prison had some kind of lifetime DSM III alcohol disorder, while 30% had a severe lifetime drug disorder.
In another study, Fazel et al. [
11] concluded that the prevalence of substance abuse and dependence among prisoners was much higher in prisoners than in the general population. Among the studies confirming a link between substance abuse and sex offenders, one study found that 85% of 113 convicted male sexual offenders had a lifetime diagnosis of substance abuse disorder according to the DSM IV criteria [
32]. Another study [
33] found that sex offenders have significant difficulties with alcohol abuse.
In agreement with others [
25,
30], in the present study a history of substance abuse was most frequently reported by those inmates who had committed sexual offences (81.8%). Of those prisoners convicted of a non-sexual violent crime (64.3%) had a confirmed history of substance abuse. In light of these data, it is evident that rehabilitation of prisoners should focus largely on substance abuse issues. In addition, when dealing with subgroups of inmates classified as having several specific risk factors for reoffending, rehabilitation must encompass these accordingly.
The low number of participants in this study was due to the relatively small population of detainees on preventive detention in Norway. This has obvious consequences since a low participation rate limits the strength of our conclusions. At the time of the investigation, 56 of 61 inmates on preventive detention were available at the prison and the current response rate was 28 of 56 (50%). While this response rate is low compared to many convenience sampling studies, this is a unique population with few similar studies from which to draw comparisons. However, when the present study was presented to the prison administration, it was underlined that according to their experience, a participation rate of around 25-30% might be obtainable, but rarely more. It is not known if the investigators' visits to the different departments to recruit study subjects influenced the response rate.
As for the non-participating prisoners in preventive detention, we have little information. During the interviews, however, some of the inmates commented that there were non-participants in great need of psychiatric assistance in their department. Consent to use information from the prisoners' files was not given by the ethics committee without each prisoner's written consent. Asking for the inmates' consent to study their personal files most likely would have reduced the participation rate even further. This assumption is based on previous observations and experience with prisoners, and their expressed suspicion towards the prison and the criminal justice system. Questions asked by the inmates during the recruitment process underscored the inmates' suspicions. Their main concerns were whether or not the information given would be forwarded to the prison administration or otherwise made accessible to anyone who could use the information against them. Thus, it was decided not to ask for the inmates' permission to access personal files.