Ireland is in the midst of an escalating homeless crisis, as evidenced by exponentially rising homeless figures (see Fig. 1). A significant number of homeless people with mental illness are currently supported within Irish prisons and hospitals. This study illustrates the impact of the homeless crisis as reflected in the volume of referrals received by psychiatry during the course of a month.
In accordance with the finding that alcohol dependency and active drug use is reported to be highly prevalent in the Irish homeless population , a significant number of this study’s homeless presenters endorsed drug and alcohol abuse. This exceeded that of the housed comparison. In relation to major affective or psychotic illness, the homeless cohort in this study was found to have a lower rate of assessed psychiatric disorder than their housed contemporaries.
Ten years ago, research on admissions to a Dublin hospital evaluated that homeless people were over-represented in the accident and emergency department due to the fact that their psychological and medical needs were not being met in primary care . The route to healthcare is not always straightforward. Almost half of homeless people in Dublin were previously found to have no medical card for free medical care and prescriptions  complicating access to primary care. The financial implication of having to pay for a primary care consultation was seen to drive a tendency to bypass primary care and attend the emergency department for treatment . Medical card acquisition is complicated by problems accessing information on entitlements and benefits, having no address, and difficulties completing the necessary forms. However, in recent years, medical card access for homeless people has improved significantly to 77% (over half that of the general population), as has access to GP care; as reflected by registration rates ; which highlights efforts of homeless services to tackle this issue. Yet, from 1997 to 2013, the rate of accident and emergency attenders among the homeless population continued to rise steadily, in concordance with an observed increase in drug use over time . This suggests that increased access to primary care services is in fact not preventing utilisation of acute secondary care services, and is complicated by the sequelae of increased drug use .
Over two thirds of homeless people referred to psychiatry in this study were previously hospitalised in a specialist psychiatric unit, representing an increase of 25% from that of the housed cohort. In a cross-sectional survey of homeless people in Dublin (n = 538) and Limerick (n = 63) in 2013 , respondents who attended the accident and emergency department were three times as likely to have previously attended a specialist psychiatric hospital service. Moreover, people who were linked in with homeless services were twice as likely to have attended a psychiatric hospital service within the previous 6 months . The fact that 66% of the people referred in this study were previously assessed by psychiatry via the SJH Emergency Department highlights the chronic physical and mental health sequelae that arise when a person experiences homelessness. Of the sample referred to psychiatry, 60% reported that they had been, or were, currently linked in with specialist community mental health services, reflecting difficulties in access, service delivery, and engagement.
Homeless people are more likely to be hospitalised than the housed population, but on-going and long-term engagement with planned health services  continues to be poor. Navigating the precarious life of homelessness requires so much energy that basic survival, shelter, and sustenance needs may be prioritised over seeking treatment. Keeping in contact with service providers can be a challenge, especially for individuals with dual diagnoses. This fact was underlined by a study showing that mentally ill alcohol dependent homeless people were 5 times more likely to lose contact with caring agencies than homeless people with mental disorders who were not dependent on alcohol . It is apparent that this lack of engagement and compliance can be a source of disillusionment to mental health service providers. As such, it is important that services adapt to needs identified by homeless people to promote as much engagement as possible.
The findings in this study highlight unemployment for homeless presenters, as access to jobs are obstructed by lack of address, literacy issues, and psychosocial factors. With the exception of one case, the entire homeless sample reported that they were not in a current relationship. Frequently, homeless people lack social capital and support that might act as a buffering factor in helping to ameliorate stress factors. (An issue highlighted by an Irish study where 47% of homeless respondents had no close relatives and 37% had no close friends that they could approach when they required support.) .
Homelessness is caused by an interaction between individual, societal/familial, and structural factors. At an individual level, poverty, substance misuse, and mental health problems, in the context of reduced social/family supports, combined with structural factors such as a lack of access to affordable housing contribute towards homelessness . Homelessness, and its inherent marginalisation, engenders a loss of safety, privacy, belonging, agency, and autonomy that renders an individual especially susceptible to ill-health. It is evident that homelessness compounds the effects of mental health difficulties and vice versa, rendering vulnerable individuals more psychologically exposed. Given the aforementioned, it is unsurprising that people with mental illness tend to remain homeless longer than people without .