Adverse SARS-CoV-2 Associated Outcomes Among People Experiencing Homelessness, Imprisonment, Supported Psychiatric Housing, Mental Disorders, Substance Abuse or Chronic Medical Disorders: A Population-Based Cohort Study Among 4.4 Million People

Research output: Working paperPreprintResearch

Background: Marginalised or deprived groups may be at high risk of a serious COVID-19 outcome. We examined adverse outcomes associated with SARS-CoV-2 infection among vulnerable segments of society.

Methods: Using health and administrative registers, we performed a population-based cohort study of 4.38 million Danes, 27 February 2020­ to 6 April 2021. Main predictors were experiences of 1) homelessness, 2) imprisonment, 3) supported psychiatric housing, 4) mental disorder, 5) substance abuse, and 6) chronic medical condition. COVID-19-related outcomes were: 1) hospitalisation, 2) intensive care, 3) 30-day mortality, and 4) overall mortality. PCR-confirmed SARS-CoV-2 infection and PCR-testing were also studied. Vulnerable groups were compared with the general population (using adjusted incidence and mortality rate ratios: IRRs, MRRs).

Findings: Among individuals with a positive PCR-test experiencing homelessness and supported psychiatric housing, 8∙6% (95% CI 6∙9-10∙4) and 11% (7∙8-14∙7), respectively, were admitted to hospital within two weeks and 1∙8% (1∙1-2∙7) and 2∙9% (1∙4-5∙1), respectively, had died within 30 days. The probability of hospitalisation was higher for all predictors compared with the general population (p=<0∙0001). After adjustments, vulnerable housing situations, i.e. homelessness, imprisonment, and supported psychiatric housing, increased the risk of adverse outcomes 1∙7 to 3∙2-times; highest 30-day MRR after COVID-19 was for homelessness (3∙2, 95% CI 2∙0-5∙1) and supported psychiatric housing: (2∙7, 1∙4-5∙2). Mental disorder, substance abuse, and chronic medical conditions were associated with 1∙1 (mental disorder and intensive care, p=0∙37) to 2∙0-times increased risk of adverse outcomes (30-day MRR for substance abuse: 2∙0, 1∙8-2∙3). Overall mortality during the study period was increased for all predictors and highest for homelessness combined with a PCR-confirmed SARS-CoV-2 infection (MRR 22∙1, 15∙2-32∙2).

Interpretation: This study highlights that pandemic preparedness should address inequalities in health, including infection prevention and vaccination of vulnerable groups. Higher awareness of people in vulnerable living situations is needed.
Original languageEnglish
PublisherSSRN: Social Science Research Network
Publication statusPublished - 2021

ID: 291613966