Severe mental illness has a high prevalence in the homeless population, with particularly high levels of psychotic illness and substance dependence, as well as risk factors for suicide and violence, a new study has found.

Postgraduate trainee in psychiatry Dr Elaine Dunne, South Lee Mental Health Services, Cork, who carried out the study, found that poor compliance and severity of illness amongst the homeless population has led to a requirement for significant input from multidisciplinary mental health team members.

Despite an estimated minimum of 4,176 adults and 1,405 children experiencing homelessness nationally, Dr Dunne said that little was formally known about the extent of the problem and its relationship to mental illness. She found that estimates of the prevalence of severe mental health illness among the homeless in other countries ranged from between 25 and 50 per cent.