Characterization of substance use in homeless patients with mental disorders

Abstract

Background

In Denmark, 42% of homeless people suffer from dual diagnosis, i.e. the co-occurrence of a substance use of alcohol and/or illegal substances and another psychiatric disorder. Dual diagnosis homeless patients often cause differential diagnostic difficulties and fail to receive effective treatment. A solid grasp of the role of substance use in these patients may inform the diagnostic decision and contribute to improve their treatment. Today, knowledge of these issues remains scarce. The purpose of this study was to explore substance use in homeless patients with mental disorders and their subjective perspectives on their substance use.

Methods

44 homeless dual diagnosis patients were included in the study. They were examined in interviews focusing on their substance use and their subjective perspective on their substance use.

Results

The most frequently used substances were cannabinoids (70.5%) and alcohol (45.5%), followed by cocaine, sedative/hypnotics, and amphetamine. The finding suggests that substance use in dual diagnosis homeless patients is a complex phenomenon with most patients (56.8%) using multiple substances. While substance use seems to contribute to keep the patients homeless, substance use was also reported to play an important role in coping with life on the streets by offering social contact and some relief from a desperate situation.

Conclusion

Substance use, mental disorder, and homelessness seem to be closely entangled, reinforcing each other and making it difficult to help these vulnerable patients. Diagnostic overshadowing may cause delays in adequate diagnosis and treatment of this group of patients.

Keywords:

• Mental illness
• homelessness
• schizophrenia
• dual diagnosis
• substance use

Ethical approval

The data were collected as a part of a quality assurance project in HOPS. The patients were all informed about quality assurance and gave written consent to participate. According to Danish legislation, quality assurance projects do not require approval from an ethical committee.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Due to the nature of the research, due to ethical and legal reasons supporting data is not available.

Additional information

Funding

LE was funded by a grant from the Lundbeck Foundation, and RH was funded by the Mental Health Services Copenhagen. Neither the Lundbeck Foundation nor the Mental Health Services Copenhagen had any influence on the study.

Notes on contributors

Lykke Elmquist

Lykke Elmquist is a medical student at the University of Copenhagen, working on this project as a part of her research year.

Mads Gram Henriksen

Mads Gram Henriksen, DMsci, PhD, MA, is an Associate Professor at the University of Copenhagen. The keypoints of his research are psychopathology, phenomenology, and philosophical issues in psychiatry.

Rasmus Handest

Rasmus Handest, MD, is a psychiatric trainee in the Mental Health Services in the Capital Region of Denmark. He is finishing his PhD on social functioning and psychopathology in patients with schizophrenia, with a focus on homeless patients.

Julie Nordgaard

Julie Nordgaard, DMsci, PhD, MD, is a clinical Professor at the University of Copenhagen. The keypoint of her research is psychopathology and the psychatric diagnostic interview from a phenomenological informed base with focus on the subjective experience.