One in six criminals are homeless prior to being sent to prison and one in two have an alcohol or drug disorder, according to researchers at the University of Limerick.
Rates of psychosis among inmates are much higher than in the rest of the population, which researchers said strengthens the argument for the development of diversion services.
Ireland has the lowest per-capita, secure psychiatric-bed availability in developed countries.
The research, described as the first systematic review of the area among Irish prisoners, is published in the Irish Journal of Psychological Medicine and has been made available by the Health Research Board.
Examining 10 separate studies, they found the following prevalence:
- Psychiatric disorder stood at 3.6%, which was in keeping with international studies on prisoners and “significantly higher” than the general population;
- Major affective disorders stood at 4.3%, lower than international estimates, but this could be linked to current screening processes in jails;
- Alcohol and substance use disorders stood at 51%, in keeping with international studies, but “substantially higher” than the general population;
- Homeless rates of prisoners on committal stood at 17%, above international estimates, and “significantly higher” that the general Irish population.
“This study confirms that a significant proportion of Irish prisoners present with a current psychotic or major affective disorder, which are potentially treatable mental illnesses,” said the study.
This finding strengthened the argument for the development of diversion services, which were geographically variable and still evolving.
“Ireland has the lowest per-capita, secure psychiatric-bed availability in developed countries,” said the report.
“Diversion services need an expansion on bed capacity within Irish mental health services.”
In relation to affective disorders, the rates were lower than internationally, but studies for female prisoners were higher.
The lower, overall levels prompted calls by researchers for a review to determine whether current screening processes were adequate in prisons here.
“The burden of harmful use or dependence on alcohol and substances in Irish prisons is substantial,” said the report.
“One in three prisoners had a current alcohol misuse or dependence and one in two a problem with current substance misuse or dependence.”
These figures were in keeping with international estimates, but substantially higher than the Irish population generally.
“Substance and alcohol misuse are seen as key risk factors for recidivism,” it said, adding that prison and probation services had invested in treatment programmes, but said services were variable geographically.
“In the Irish context, treatment programmes for women, those specific to alcohol misuse, as well as those focused on novel drugs of misuse, are seen as gaps in provision,” it said.
It said research showed homelessness was “both a cause and consequence of imprisonment”.