Determinants of Hospital Use and Physician Services Among Adults With a History of Homelessness.

Background: People experiencing homelessness have diverse patterns of healthcare use. This study examined the distribution and determinants of healthcare encounters among adults with a history of homelessness. Methods: Administrative healthcare records were linked with survey data for a general cohort of adults with a history of homelessness and a cohort of homeless adults with mental illness. Binary and count models were used to identify factors associated with hospital admissions, emergency department visits and physician visits for comparison across the 2 cohorts. Results: During the 1-year follow-up period, a higher proportion of people in the cohort with a mental illness used any inpatient (27% vs 14%), emergency (63% vs 53%), or physician services (90% vs 76%) compared to the general homeless cohort. People from racialized groups were less likely use nearly all health services, most notably physician services. Other factors, such as reporting of a regular source of care, poor perceived general health, and diagnosed chronic conditions were associated with higher use of all health services except psychiatric inpatient care. Conclusion: When implementing interventions for patients with the greatest health needs, we must consider the unique factors that contribute to higher healthcare use, as well as the barriers to healthcare access.

Vaccine effectiveness against SARS-CoV-2 infection and severe outcomes among individuals with immune-mediated inflammatory diseases tested between March 1 and Nov 22, 2021, in Ontario, Canada: a population-based analysis.

Background: We estimated COVID-19 vaccine effectiveness against SARS-CoV-2 infection and severe COVID-19 outcomes among individuals with immune-mediated inflammatory diseases in Ontario, Canada. Methods: In this population-based analysis, we used a test-negative design across four immune-mediated inflammatory disease population-based cohorts, comprising individuals with rheumatoid arthritis, ankylosing spondylitis, psoriasis, and inflammatory bowel disease. We identified all SARS-CoV-2 tests done in these populations between March 1 and Nov 22, 2021 (a period in which there was rapid uptake of vaccines, and the alpha [B.1.1.7] and delta [B.1.617.2] SARS-CoV-2 variants were predominantly circulating in Canada) and separately assessed outcomes of SARS-CoV-2 infection and severe COVID-19 outcomes (hospitalisation due to COVID-19 and death due to COVID-19) for each disease group. We used multivariable logistic regression to estimate the effectiveness of one, two, and three doses of mRNA-based COVID-19 vaccine (BNT162b2 [Pfizer-BioNTech], or mRNA-1273 [Moderna]) among individuals at the time of SARS-CoV-2 testing. Findings: Between March 1 and Nov 22, 2021, we identified 2127 (5·9%) test-positive cases among 36 145 individuals (26 476 [73·2%] were female and 9669 [26·8%] were male) with rheumatoid arthritis tested, 476 (6·1%) test-positive cases among 7863 individuals (4130 [52·5%] were female and 3733 [47·5%] were male) with ankylosing spondylitis tested, 3089 (6·5%) test-positive cases among 47 199 individuals (26 062 [55·2%] were female and 21 137 [44·8%] were male) with psoriasis tested, and 1702 (5·4%) test-positive cases among 31 311 individuals (17 716 [56·6%] were female and 13 595 [43·4%] were male) with inflammatory bowel disease tested. Adjusted vaccine effectiveness of two doses against infection was 83% (95% CI 80-86) in those with rheumatoid arthritis, 89% (83-93) among those with ankylosing spondylitis, 84% (81-86) among those with psoriasis, and 79% (74-82) among those with inflammatory bowel disease. After two vaccine doses, effectiveness against infection generally peaked 31-60 days after vaccination and waned gradually with each additional month. Vaccine effectiveness against severe outcomes after two doses was 92% (95% CI 88-95) in those with rheumatoid arthritis, 97% (83-99) among those with ankylosing spondylitis, 92% (86-95) among those with psoriasis, and 94% (88-97) among those with inflammatory bowel disease. Vaccine effectiveness after a third dose against infection was similar to or higher than after the second dose (ranging from 76% [47-89] to 96% [72-99]), although due to a paucity of events, estimates could not be calculated for some subgroups for severe outcomes. Interpretation: Two vaccine doses were found to be highly effective against both SARS-CoV-2 infection and severe COVID-19 outcomes in patients with rheumatoid arthritis, ankylosing spondylitis, psoriasis, and inflammatory bowel disease during the study period. Research is needed to determine the durability of effectiveness of three doses over time, particularly against emerging variants. Funding: Public Health Agency of Canada.

COVID-19 Vaccination Uptake Among Individuals With Immune-mediated Inflammatory Diseases in Ontario, Canada, Between December 2020 and October 2021: A Population-based Analysis.

OBJECTIVE: We assessed coronavirus disease 2019 (COVID-19) vaccine uptake among individuals with immune-mediated inflammatory diseases (IMIDs) and the Ontario general population. METHODS: We studied all residents aged ≥ 16 years who were alive and enrolled in the Ontario Health Insurance Plan as of December 14, 2020, when vaccination commenced (n = 12,435,914). Individuals with rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), psoriasis (PsO), and inflammatory bowel disease (IBD) were identified using established disease-specific case definitions applied to health administrative data. Vaccination status was extracted from the provincial COVaxON registry. Weekly cumulative proportions of first and second doses up until October 3, 2021, were expressed as the vaccinated percentage of each disease group, compared to the general Ontario population, and stratified by age. RESULTS: By October 3, 2021, the cumulative percentage with at least 1 dose was 82.1% for the general population, 88.9% for those with RA, 87.4% for AS, 90.6% for PsA, 87.3% for PsO, and 87.0% for IBD. There was also a higher total cumulative percentage with 2 doses among IMIDs (83.8-88.2%) vs the general population (77.9%). The difference was also evident when stratifying by age. Individuals with IMIDs in the youngest age group initially had earlier uptake than the general population but remain the lowest age group with 2 doses (70.6% in the general population vs. 73.7-79.2% across IMID groups). CONCLUSION: While implementation of COVID-19 vaccination programs has differed globally, these Canadian estimates are the first to reassuringly show higher COVID-19 vaccine uptake among individuals with IMIDs.

Acute mental health service use following onset of the COVID-19 pandemic in Ontario, Canada: a trend analysis.

BACKGROUND: The extent to which heightened distress during the COVID-19 pandemic translated to increases in severe mental health outcomes is unknown. We examined trends in psychiatric presentations to acute care settings in the first 12 months after onset of the pandemic. METHODS: This was a trends analysis of administrative population data in Ontario, Canada. We examined rates of hospitalizations and emergency department visits for mental health diagnoses overall and stratified by sex, age and diagnostic grouping (e.g., mood disorders, anxiety disorders, psychotic disorders), as well as visits for intentional self-injury for people aged 10 to 105 years, from January 2019 to March 2021. We used Joinpoint regression to identify significant inflection points after the onset of the pandemic in March 2020. RESULTS: Among the 12 968 100 people included in our analysis, rates of mental health-related hospitalizations and emergency department visits declined immediately after the onset of the pandemic (peak overall decline of 30% [hospitalizations] and 37% [emergency department visits] compared to April 2019) and returned to near prepandemic levels by March 2021. Compared to April 2019, visits for intentional self-injury declined by 33% and remained below prepandemic levels until March 2021. We observed the largest declines in service use among adolescents aged 14 to 17 years (55% decline in hospitalizations, 58% decline in emergency department visits) and 10 to 13 years (56% decline in self-injury), and for those with substance-related disorders (33% decline in emergency department visits) and anxiety disorders (61% decline in hospitalizations). INTERPRETATION: Contrary to expectations, the abrupt decline in acute mental health service use immediately after the onset of the pandemic and the return to near prepandemic levels that we observed suggest that changes and stressors in the first 12 months of the pandemic did not translate to increased service use. Continued surveillance of acute mental health service use is warranted.