Morbidity and Mortality Patterns Among Marginalized Individuals: Insights from a Copenhagen Shelter Health Clinic Cohort

<b>Objective:</b> Homelessness is a significant social issue in developed countries, linked to high rates of substance use, psychiatric disorders, and chronic somatic health conditions, which contribute to premature mortality. Despite Denmark's comprehensive welfare system, marginalized groups, including people in homelessness, face barriers to accessing healthcare, resulting in increased use of acute care services and poorer health outcomes compared to the general population. This study examines the health burden and mortality of some of Denmark's most marginalized individuals by analyzing registry data from users of a low-threshold healthcare service placed at the open drug scene in Copenhagen, Denmark. <b>Methods:</b> This retrospective cohort study spans seven years (2009-2015). The study includes 1,242 individual health service users identified through patient records from the low threshold service linked with demographic, educational, and healthcare utilization data from Danish registries. No approval from the Danish Research Ethics Committees for the Capital Region was needed since only national registers were used. <b>Results:</b> The population was predominantly male with a median age of 42 years. Most participants were of ethnic Danish origin and had low educational attainment. This study revealed high morbidity, with significant proportions of the population affected by somatic diseases, psychiatric disorders, and substance use disorders, including 56% with Dual Diagnosis and 53% with Dual Diagnosis and somatic disease (Triple Diagnosis). Analysis of mortality showed 158 deaths, predominantly among males, with substance use-related causes and cardiovascular diseases being the leading causes of death. The mean age at death was 47.3 years, with a notable proportion occurring at a relatively young age. <b>Conclusion:</b> Our study reveals a high prevalence of both somatic and psychiatric disorders among the shelter health clinic users. Findings indicate that they are in a similar or often poorer health state than Danish shelter users overall, with a high prevalence of dual diagnoses alongside chronic somatic diseases (Triple Diagnosis) and early disease onset. This highlights the need for targeted support and the implementation of primary prevention measures to slow disease progression and improve healthcare access.