Does receipt of social housing impact mental health? Results of a quasi-experimental study in the Greater Toronto Area.

Affordable housing is commonly described as an important determinant of health, but there are relatively few intervention studies of the effects of housing on health. In this paper, we describe the results of a quasi-experimental, longitudinal study investigating the impacts of receiving social housing among a cohort of 502 people on waitlists for social housing in the Greater Toronto Area, Canada. Specifically, we sought to determine if adults who received housing were more likely than a control group to show improvements in depression, psychological distress, and self-rated mental health 6, 12 and 18 months after moving to housing. Amongst the participants, 137 received social housing and completed at least one follow-up interview; 304 participants did not receive housing and completed at least one follow-up interview and were treated as a control group (47 people provided data to both groups). The difference-in-differences technique was used to estimate the effect of receiving housing by comparing changes in the outcomes over time in the housed (intervention) group and the group that remained on the waitlist for social housing (control group). Adjusted mixed effects linear models showed that receiving housing resulted in significant decreases in psychological distress and self-rated mental health between the groups. Improvements in self-rated mental health between the groups were observed 6, 12 and 18 months after receiving housing (6 months, +2.9, p < 0.05; 12 months, +2.6, p < 0.05; 18 months, +3.0, p < 0.05). Reductions in psychological distress (-1.4, p < 0.05) were observed 12 months after receiving housing. Overall findings suggest that receiving subsidized housing improves mental health over a 6-to-18-month time horizon. This has policy and funding implications suggesting a need to reduce wait times and expand access to subsidized housing.

The effect of cash transfers on health in high-income countries: A scoping review.

High-income countries use cash transfer programs to mitigate poverty, in part to improve the health of low-income populations and potentially reduce their use of public health care. This review synthesizes evidence from studies that employed experimental or quasi-experimental designs to evaluate the effect of cash transfer interventions on health outcomes or health care utilization in high-income countries. We excluded interventions if they required prior contributions for eligibility, substituted cash transfers for in-kind services, or were contingent on specific health behaviours, and excluded studies published before 1970. We searched 14 academic databases on May 13, 2022 and April 18, 2023, identifying 20,978 unique records. After screening, 164 studies were included. These studies covered interventions in 14 countries, with the largest share from the United States. The most common health outcomes examined were fertility, birth weight, self-rated health, tobacco use, and depression. We classified studies into seven intervention categories and eight health outcome domains, and identified where systematic reviews may be possible. We found relatively few studies examining health care utilization as an outcome and identify this as a knowledge gap. We categorized effects as beneficial or harmful, except for fertility and health care utilization where effects were categorized as increase or decrease. With insufficient consistency of outcomes for meta-analysis, we employed a vote count and sign test to assess the presence of any effect. Across the six relevant health domains, 98 of 130 studies (.75; 95% CI: .67, .82) reported a beneficial median effect, significantly different from the null value of 50% (p = .000). Of 37 studies examining fertility, 23 showed increases (.62; 95% CI: .46, .76) in fertility, which did not clear our threshold for statistical significance using conservative assumptions (p = .094). However, a larger share of studies reported increased fertility for child/family benefits (.69, n = 26) than for employment-related cash transfers (.44, n = 9). Results for health care utilization were evenly distributed (5 increase, 4 inconsistent, 6 decrease), but these are difficult to interpret as outcomes include both preventive and acute care. Our study provides replicable methods to enable future meta-analyses.

Disparities in healthcare costs of people experiencing homelessness in Toronto, Canada in the post COVID-19 pandemic era: a matched cohort study.

BACKGROUND: Evidence is limited about healthcare cost disparities associated with homelessness, particularly in recent years after major policy and resource changes affecting people experiencing homelessness occurred after the onset of the COVID-19 pandemic. We estimated 1-year healthcare expenditures, overall and by type of service, among a representative sample of people experiencing homelessness in Toronto, Canada, in 2021 and 2022, and compared these to costs among matched housed and low-income housed individuals. METHODS: Data from individuals experiencing homelessness participating in the Ku-gaa-gii pimitizi-win cohort study were linked with Ontario health administrative databases. Participants (n = 640) were matched 1:5 by age, sex-assigned-at-birth and index month to presumed housed individuals (n = 3,200) and to low-income presumed housed individuals (n = 3,200). Groups were followed over 1 year to ascertain healthcare expenditures, overall and by healthcare type. Generalized linear models were used to assess unadjusted and adjusted mean cost ratios between groups. RESULTS: Average 1-year costs were $12,209 (95% CI $9,762-$14,656) among participants experiencing homelessness compared to $1,769 ($1,453-$2,085) and $1,912 ($1,510-$2,314) among housed and low-income housed individuals. Participants experiencing homelessness had nearly seven times (6.90 [95% confidence interval [CI] 5.98-7.97]) the unadjusted mean ratio (MR) of costs as compared to housed persons. After adjustment for number of comorbidities and history of healthcare for mental health and substance use disorders, participants experiencing homelessness had nearly six times (adjusted MR 5.79 [95% CI 4.13-8.12]) the expected healthcare costs of housed individuals. The two housed groups had similar costs. CONCLUSIONS: Homelessness is associated with substantial excess healthcare costs. Programs to quickly resolve and prevent cases of homelessness are likely to better meet the health and healthcare needs of this population while being a more efficient use of public resources.

Social isolation and loneliness among people living with experience of homelessness: a scoping review.

Social isolation and loneliness (SIL) are public health challenges that disproportionally affect individuals who experience structural and socio-economic exclusion. The social and health outcomes of SIL for people with experiences of being unhoused have largely remained unexplored. Yet, there is limited synthesis of literature focused on SIL to appropriately inform policy and targeted social interventions for people with homelessness experience. The aim of this scoping review is to synthesize evidence on SIL among people with lived experience of homelessness and explore how it negatively impacts their wellbeing. We carried out a comprehensive literature search from Medline, Embase, Cochrane Library, PsycINFO, CINAHL, Sociological Abstracts, and Web of Science's Social Sciences Citation Index and Science Citation Index for peer-reviewed studies published between January 1st, 2000 to January 3rd, 2023. Studies went through title, abstract and full-text screening conducted independently by at least two reviewers. Included studies were then analyzed and synthesized to identify the conceptualizations of SIL, measurement tools and approaches, prevalence characterization, and relationship with social and health outcomes. The literature search yielded 5,294 papers after removing duplicate records. Following screening, we retained 27 qualitative studies, 23 quantitative studies and two mixed method studies. SIL was not the primary objective of most of the included articles. The prevalence of SIL among people with homelessness experience varied from 25 to 90% across studies. A range of measurement tools were used to measure SIL making it difficult to compare results across studies. Though the studies reported associations between SIL, health, wellbeing, and substance use, we found substantial gaps in the literature. Most of the quantitative studies were cross-sectional, and only one study used health administrative data to ascertain health outcomes. More studies are needed to better understand SIL among this population and to build evidence for actionable strategies and policies to address its social and health impacts.

Disparities in all-cause mortality among people experiencing homelessness in Toronto, Canada during the COVID-19 pandemic: a cohort study.

People experiencing homelessness have historically had high mortality rates compared to housed individuals in Canada, a trend believed to have become exacerbated during the COVID-19 pandemic. In this matched cohort study conducted in Toronto, Canada, we investigated all-cause mortality over a one-year period by following a random sample of people experiencing homelessness (n = 640) alongside matched housed (n = 6,400) and low-income housed (n = 6,400) individuals. Matching criteria included age, sex-assigned-at-birth, and Charlson comorbidity index. Data were sourced from the Ku-gaa-gii pimitizi-win cohort study and administrative databases from ICES. People experiencing homelessness had 2.7 deaths/100 person-years, compared to 0.7/100 person-years in both matched unexposed groups, representing an all-cause mortality unadjusted hazard ratio (uHR) of 3.7 (95% CI, 2.1-6.5). Younger homeless individuals had much higher uHRs than older groups (ages 25-44 years uHR 16.8 [95% CI 4.0-70.2]; ages 45-64 uHR 6.8 [95% CI 3.0-15.1]; ages 65+ uHR 0.35 [95% CI 0.1-2.6]). Homeless participants who died were, on average, 17 years younger than unexposed individuals. After adjusting for number of comorbidities and presence of mental health or substance use disorder, people experiencing homelessness still had more than twice the hazard of death (aHR 2.2 [95% CI 1.2-4.0]). Homelessness is an important risk factor for mortality; interventions to address this health disparity, such as increased focus on homelessness prevention, are urgently needed.

Uptake of COVID-19 vaccination among community-dwelling individuals receiving healthcare for substance use disorder and major mental illness: a matched retrospective cohort study.

Introduction: Patients with major mental illness (MMI) and substance use disorders (SUD) face barriers in accessing healthcare. In this population-based retrospective cohort study, we investigated the uptake of COVID-19 vaccination in Ontario, Canada among community-dwelling individuals receiving healthcare for major mental illness (MMI) and/or substance use disorders (SUD), comparing them to matched general population controls. Methods: Using linked health administrative data, we identified 337,290 individuals receiving healthcare for MMI and/or SUD as of 14 December 2020, matched by age, sex, and residential geography to controls without such healthcare. Follow-up extended until 31 December 2022 to document vaccination events. Results: Overall, individuals receiving healthcare for MMI and/or SUD (N = 337,290) had a slightly lower uptake of first (cumulative incidence 82.45% vs. 86.44%; hazard ratio [HR] 0.83 [95% CI 0.82-0.83]) and second dose (78.82% vs. 84.93%; HR 0.77 [95% CI 0.77-0.78]) compared to matched controls. Individuals receiving healthcare for MMI only (n = 146,399) had a similar uptake of first (87.96% vs. 87.59%; HR 0.97 [95% CI 0.96-0.98]) and second dose (86.09% vs. 86.05%, HR 0.94 [95% CI 0.93-0.95]). By contrast, individuals receiving healthcare for SUD only (n = 156,785) or MMI and SUD (n = 34,106) had significantly lower uptake of the first (SUD 78.14% vs. 85.74%; HR 0.73 [95% CI 0.72-0.73]; MMI & SUD 78.43% vs. 84.74%; HR 0.76 [95% CI 0.75-0.77]) and second doses (SUD 73.12% vs. 84.17%; HR 0.66 [95% CI 0.65-0.66]; MMI & SUD 73.48% vs. 82.93%; HR 0.68 [95% CI 0.67-0.69]). Discussion: These findings suggest that effective strategies to increase vaccination uptake for future COVID-19 and other emerging infectious diseases among community-dwelling people with SUD are needed.

MEM-based pangenome indexing for k-mer queries.

Pangenomes are growing in number and size, thanks to the prevalence of high-quality long-read assemblies. However, current methods for studying sequence composition and conservation within pangenomes have limitations. Methods based on graph pangenomes require a computationally expensive multiple-alignment step, which can leave out some variation. Indexes based on k-mers and de Bruijn graphs are limited to answering questions at a specific substring length k. We present Maximal Exact Match Ordered (MEMO), a pangenome indexing method based on maximal exact matches (MEMs) between sequences. A single MEMO index can handle arbitrary-length queries over pangenomic windows. MEMO enables both queries that test k-mer presence/absence (membership queries) and that count the number of genomes containing k-mers in a window (conservation queries). MEMO's index for a pangenome of 89 human autosomal haplotypes fits in 2.04 GB, 8.8× smaller than a comparable KMC3 index and 11.4× smaller than a PanKmer index. MEMO indexes can be made smaller by sacrificing some counting resolution, with our decile-resolution HPRC index reaching 0.67 GB. MEMO can conduct a conservation query for 31-mers over the human leukocyte antigen locus in 13.89 seconds, 2.5x faster than other approaches. MEMO's small index size, lack of k-mer length dependence, and efficient queries make it a flexible tool for studying and visualizing substring conservation in pangenomes.

Identification of homelessness using health administrative data in Ontario, Canada following a national coding mandate: a validation study.

OBJECTIVES: Conducting longitudinal health research about people experiencing homelessness poses unique challenges. Identification through administrative data permits large, cost-effective studies; however, case validity in Ontario is unknown after a 2018 Canada-wide policy change mandating homelessness coding in hospital databases. We validated case definitions for identifying homelessness using Ontario health administrative databases after introduction of this coding mandate. STUDY DESIGN AND SETTING: We assessed 42 case definitions in a representative sample of people experiencing homelessness in Toronto (n = 640) from whom longitudinal housing history (ranging from 2018 to 2022) was obtained, and a randomly selected sample of presumably housed people (n = 128,000) in Toronto. We evaluated sensitivity, specificity, positive and negative predictive values, and positive likelihood ratios to select an optimal definition, and compared the resulting true positives against false positives and false negatives to identify potential causes of misclassification. RESULTS: The optimal case definition included any homelessness indicator during a hospital-based encounter within 180 days of a period of homelessness (sensitivity = 52.9%; specificity = 99.5%). For periods of homelessness with ≥1 hospital-based healthcare encounter, the optimal case definition had greatly improved sensitivity (75.1%) while retaining excellent specificity (98.5%). Review of false positives suggested that homeless status is sometimes erroneously carried forward in healthcare databases after an individual transitioned out of homelessness. CONCLUSION: Case definitions to identify homelessness using Ontario health administrative data exhibit moderate to good sensitivity and excellent specificity. Sensitivity has more than doubled since the implementation of a national coding mandate. Mandatory collection and reporting of homelessness information within administrative data present invaluable opportunities for advancing research on the health and healthcare needs of people experiencing homelessness.

Disparities in diabetes processes of care among people experiencing homelessness: An opportunity for intervention.

AIMS: To compare processes of diabetes care by homeless status. METHODS: A population-based propensity matched cohort study was conducted in Ontario, Canada. People with diabetes were identified in administrative healthcare data between April 2006 and March 2019. Those with a documented history of homelessness were matched to non-homeless controls. Data on processes of care measures included glucose monitoring tests, screening for microvascular complications, and physician follow-up. Differences in processes of care were compared by homeless status using proportions, risk ratios, and rate ratios. RESULTS: Of the 1,076,437 people with diabetes, 5219 matched pairs were identified. Homelessness was associated with fewer tests for glycated hemoglobin (RR = 0.63; 95 %CI: 0.60-0.67), LDL cholesterol (RR = 0.80; 95 %CI: 0.78-0.82), serum creatinine (RR = 0.94; 95 %CI: 0.92-0.97), urine protein quantification (RR = 0.62; 95 %CI: 0.59-0.66), and eye examinations (RR = 0.74; 95 %CI: 0.71-0.77). People with a history of homelessness were less likely to use primary care for diabetes management (RR = 0.62; 95 %CI: 0.59-0.66) or specialist care (RR = 0.87; 95 %CI: 0.83-0.91) compared to non-homeless controls. CONCLUSIONS: Disparities in diabetes care are evident for people with a history of homelessness and contribute to excess morbidity in this population. These data provide an impetus for investment in tailored interventions to improve healthcare equity and prevent long-term complications.

The role of housing stability in predicting social capital: Exploring social support and psychological integration as mediators for individuals with histories of homelessness and vulnerable housing.

Social capital is a collective asset important for individual and population well-being. Individuals who experience homelessness may face barriers in accessing social capital due to health challenges, small social networks, and social exclusion. Data from a 4-year longitudinal study was used to determine if housing stability predicted greater social capital and if this relationship was mediated by social support and psychological integration for a sample of 855 homeless and vulnerably housed participants living in three Canadian cities. Findings showed that housing stability was not associated with trust and linking social capital. However, higher levels of social support and psychological integration had a mediating effect on the association between housing stability and trust and linking social capital. These findings highlight the importance of social support and psychological integration as means of promoting social capital for people who experience homelessness and vulnerable housing. Social interventions for housed individuals with histories of homelessness may be an avenue to foster greater social capital by building relationships with neighbors and connections to community resources and activities.

Service restrictions from emergency shelters among people experiencing homelessness: Uncovering pathways into unsheltered homelessness and institutional circuitry.

Service restrictions refer to temporary or permanent bans of individuals from a program or an organization's services, and are widely used in emergency shelter systems. Limited research exists on how service restrictions unfold and their impacts on people experiencing homelessness. This qualitative study used in-depth interviews with timeline mapping to examine the antecedents and consequences of service restrictions from emergency shelters among people experiencing homelessness in two cities in Ontario, Canada. A total of 49 people experiencing homelessness who had been restricted from an emergency shelter program in the past year were recruited and included in the study analysis. A pragmatic and integrative approach was used for data analysis that involved the development of meta-matrices to identify prominent and divergent perspectives and experiences with regard to service restriction antecedents and consequences. Study findings underscored that service restrictions were often the result of violence and aggression, primarily between service users. There were regional differences in other service restriction reasons, including substance use and possession. Service restrictions affected the shelter status of almost all participants, with many subsequently experiencing unsheltered homelessness, and cycling through institutional health, social, and criminal justice services (i.e., institutional circuitry). Other health and social consequences included substance use relapses and hospitalizations; cold-related injuries due to post-restriction unsheltered homelessness; suicidality; food insecurity; diminished contact with support network and connections; and intense feelings of anger, fear, and hopelessness. Overall, the study findings advance our understanding of the role of homeless services in pathways into unsheltered homelessness and institutional circuitry, which raise critical questions about how to mitigate the harms associated with service restrictions, while concurrently facilitating safety and upholding the rights of people experiencing homelessness and emergency shelter staff.

Trends in emergency department visits during cold weather seasons among patients experiencing homelessness in Ontario, Canada: a retrospective population-based cohort study.

PURPOSE: Recent anecdotal reports suggest increasing numbers of people experiencing homelessness are visiting emergency departments (EDs) during cold weather seasons due to inadequate shelter availability. We examined monthly ED visits among patients experiencing homelessness to determine whether there has been a significant increase in such visits in 2022/2023 compared to prior years. METHODS: We used linked health administrative data to identify cohorts experiencing homelessness in Ontario between October and March of the 2018/2019 to 2022/2023 years. We analyzed the monthly rate of non-urgent ED visits as a proxy measure of visits plausibly attributable to avoidance of cold exposure, examining rates among patients experiencing homelessness compared to housed patients. We excluded visits for overdose or COVID-19. We assessed level and significance of change in the 2022/2023 year as compared to previous cold weather seasons using Poisson regression. RESULTS: We identified a total of 21,588 non-urgent ED visits across the observation period among patients experiencing homelessness in Ontario. Non-urgent ED visits increased 27% (RR 1.24 [95% CI 1.14-1.34]) in 2022/2023 compared to previous cold weather seasons. In Toronto, such visits increased by 70% (RR 1.68 [95% CI 1.57-1.80]). Among housed patients, non-urgent ED visits did not change significantly during this time period. CONCLUSION: Rates of ED visits plausibly attributable to avoidance of cold exposure by individuals experiencing homelessness increased significantly in Ontario in 2022/2023, most notably in Toronto. This increase in ED visits may be related to inadequate access to emergency shelter beds and warming services in the community.

RéSUMé: OBJECTIFS: Des rapports anecdotiques récents suggèrent qu'un nombre croissant de personnes en situation d'itinérance visitent les services d'urgence (SU) pendant les saisons froides en raison de la disponibilité insuffisante d'hébergement d'urgence. Nous avons examiné les visites mensuelles aux urgences chez les personnes en situation d'itinérance afin de déterminer s'il y a eu une augmentation significative de ces visites en 2022-2023 par rapport aux années précédentes. MéTHODES: Nous avons utilisé des données administratives de santé liées pour identifier les cohortes de personnes en situation d'itinérance en Ontario entre octobre et mars des années 2018/2019 à 2022/2023. Nous avons analysé le taux mensuel de visites aux urgences non urgentes comme mesure approximative des visites vraisemblablement attribuables à l'évitement de l'exposition au froid, en examinant les taux chez les personnes en situation d'itinérance par rapport aux patients logés. Nous avons exclu les visites pour surdose ou COVID-19. Nous avons évalué le niveau et l'importance du changement dans l'année 2022/2023 par rapport aux saisons froides précédentes en utilisant la régression de Poisson. RéSULTATS: Nous avons recensé un total de 21 588 visites non urgentes aux urgences au cours de la période d'observation chez des personnes en situation d'itinérance en Ontario. Les visites aux urgences non urgentes ont augmenté de 27 % (RR 1,24 [IC à 95 % 1,14-1,34]) en 2022­2023 par rapport aux saisons froides précédentes. À Toronto, ces visites ont augmenté de 70 % (RR 1,68 [IC à 95 % 1,57-1,80]). Parmi les patients logés, les visites aux urgences non urgentes n'ont pas changé de façon significative pendant cette période. CONCLUSIONS: Les taux de visites aux urgences attribuables vraisemblablement à l'évitement de l'exposition au froid par les personnes en situation d'itinérance ont augmenté considérablement en Ontario en 2022­2023, surtout à Toronto. Cette augmentation du nombre de visites aux urgences peut être liée à un accès inadéquat aux lits des refuges d'urgence et aux services de réchauffement dans la collectivité.

Enhancing detection of SARS-CoV-2 re-infections using longitudinal sero-monitoring: demonstration of a methodology in a cohort of people experiencing homelessness in Toronto, Canada.

BACKGROUND: Accurate estimation of SARS-CoV-2 re-infection is crucial to understanding the connection between infection burden and adverse outcomes. However, relying solely on PCR testing results in underreporting. We present a novel approach that includes longitudinal serologic data, and compared it against testing alone among people experiencing homelessness. METHODS: We recruited 736 individuals experiencing homelessness in Toronto, Canada, between June and September 2021. Participants completed surveys and provided saliva and blood serology samples every three months over 12 months of follow-up. Re-infections were defined as: positive PCR or rapid antigen test (RAT) results > 90 days after initial infection; new serologic evidence of infection among individuals with previous infection who sero-reverted; or increases in anti-nucleocapsid in seropositive individuals whose levels had begun to decrease. RESULTS: Among 381 participants at risk, we detected 37 re-infections through PCR/RAT and 98 re-infections through longitudinal serology. The comprehensive method identified 37.4 re-infection events per 100 person-years, more than four-fold more than the rate detected through PCR/RAT alone (9.0 events/100 person-years). Almost all test-confirmed re-infections (85%) were also detectable by longitudinal serology. CONCLUSIONS: Longitudinal serology significantly enhances the detection of SARS-CoV-2 re-infections. Our findings underscore the importance and value of combining data sources for effective research and public health surveillance.

Opioid-related overdose deaths among people experiencing homelessness, 2017 to 2021: A population-based analysis using coroner and health administrative data from Ontario, Canada.

AIMS: To measure the change in proportion of opioid-related overdose deaths attributed to people experiencing homelessness and to compare the opioid-related fatalities between individuals experiencing homelessness and not experiencing homelessness at time of death. DESIGN, SETTING AND PARTICIPANTS: Population-based, time-trend analysis using coroner and health administrative databases from Ontario, Canada from 1 July 2017 and 30 June 2021. MEASUREMENTS: Quarterly proportion of opioid-related overdose deaths attributed to people experiencing homelessness. We also obtained socio-demographic and health characteristics of decedents, health-care encounters preceding death, substances directly contributing to death and circumstances surrounding deaths. FINDINGS: A total of 6644 individuals (median age = 40 years, interquartile range = 31-51; 74.1% male) experienced an accidental opioid-related overdose death, among whom 884 (13.3%) were identified as experiencing homelessness at the time of death. The quarterly proportion of opioid-related overdose deaths attributed to people experiencing homelessness increased from 7.2% (26/359) in July-September 2017 to 16.8% (97/578) by April-June 2021 (trend test P < 0.01). Compared with housed decedents, those experiencing homelessness were younger (61.3 versus 53.1% aged 25-44), had higher prevalence of mental health or substance use disorders (77.1 versus 67.1%) and more often visited hospitals (32.1 versus 24.5%) and emergency departments (82.6 versus 68.5%) in the year prior to death. Fentanyl and its analogues more often directly contributed to death among people experiencing homelessness (94.0 versus 81.4%), as did stimulants (67.4 versus 51.6%); in contrast, methadone was less often present (7.8 versus 12.4%). Individuals experiencing homelessness were more often in the presence of a bystander during the acute toxicity event that led to death (55.8 versus 49.7%); and where another individual was present, more often had a resuscitation attempted (61.7 versus 55.1%) or naloxone administered (41.2 versus 28.9%). CONCLUSIONS: People experiencing homelessness account for an increasing proportion of fatal opioid-related overdoses in Ontario, Canada, reaching nearly one in six such deaths in 2021.

Results of posterior spinal fusion after failed anterior vertebral body tethering.

PURPOSE: In patients with adolescent idiopathic scoliosis (AIS) undergoing anterior vertebral tethering (AVBT), some will subsequently require posterior spinal fusion (PSF). Limited data exist on clinical and radiographic outcomes of fusion after tether failure. METHODS: 490 patients who underwent AVBT were retrospectively analyzed. Twenty patients (4.1%) subsequently underwent conversion to PSF. A control group of patients with primary PSF (no previous AVBT) was matched for comparison. Data were compared using paired t-tests and Fisher Exact Tests. RESULTS: There was a significant increase in estimated blood loss (EBL) (p = 0.002), percent estimated blood volume (%EBV) (p = 0.013), operative time (p = 0.002), and increased amount of fluoroscopy (mGy) (p = 0.04) as well as number of levels fused (p = 0.02) in the AVBT conversion group compared to primary fusion. However, no difference was found in implant density (p = 0.37), blood transfusions (p = 0.11), or intraoperative neuromonitoring events (p > 0.99). Both groups attained similar thoracic and lumbar percent correction (major coronal curve angle) from pre-op to the latest follow-up (thoracic p = 0.507, lumbar p = 0.952). CONCLUSION: A subset of patients with AVBT will require conversion to PSF. Although technically more challenging, revision surgery can be safely performed with similar clinical and radiographic outcomes to primary PSF.

Social Determinants of Health in Pediatric Ophthalmology Patients: Availability of Data in the Electronic Health Record and Association With Clinic Attendance.

Purpose: To characterize the availability of social determinants of health data in the electronic health record of pediatric ophthalmology patients and to examine the association of social determinants of health with attendance at scheduled operating room and clinic visits. Methods: This was a retrospective cohort study of pediatric ophthalmology patients seen at The Hospital for Sick Children between June 1, 2018, and May 23, 2022. Data were collected on demographics, diagnosis, and management-plan. The χ2 tests and multivariable regression were used to examine associations between social determinants of health and attendance at scheduled operating room and clinic visits. Results: The cohort consisted of 26,102 study subjects with 31,288 unique eye-related diagnoses representing 57 unique ICD-10 codes. Availability of data in the electronic health record ranged from 100% for sex, age and postal code to 0.1% for ethnic group. Female sex (P = 0.004) and urbanicity (P = 0.05) were associated with higher operating room visit cancellations. Female sex (P = 0.002), age group 0-13 (P ≤ 0.001), low-medium neighborhood income quintile (P ≤ 0.001), residence of Northern Ontario (P ≤ 0.001), and urbanicity (P ≤ 0.001) were associated with higher clinic visit cancellations and no-shows. Conclusions: At a major tertiary-care hospital in Canada, key social determinant data such as ethnicity are not consistently available in the electronic health record of pediatric ophthalmology patients. Female sex, younger age, and living in a rural area or neighborhood with low-medium income quintile may be predictors of missed visits and require further study. Translational Relevance: This study highlights a need for improved documentation of social determinants of health variables in electronic health records.

Hospital Care for Patients Uninsured due to Immigration Status during the COVID-19 Pandemic in Toronto: Lessons from Front-Line Knowledge Translation.

Before the COVID-19 pandemic, patients in Ontario who were uninsured due to immigration status faced barriers to hospital care that resulted in preventable illness and death. In March 2020, the Ontario Ministry of Health issued a memo indicating that it would pay for medically necessary hospital services for uninsured patients (Ontario Ministry of Health 2020). Front-line providers and research workers associated with the Health Network for Uninsured Clients (HNUC) set out to ensure that hospitals in Toronto implemented the ministry's memo. In this paper, we demonstrate a model of front-line worker-led knowledge translation informed by real-time data and anchored in clearly articulated values and goals. On April 1, 2023, the Ontario Ministry of Health cancelled this uninsured coverage (Ontario Ministry of Health 2023). Healthcare provider associations, grassroots groups and coalitions - including the HNUC - are mobilizing to see this uninsured coverage reinstated.

The complete sequence of a human Y chromosome.

The human Y chromosome has been notoriously difficult to sequence and assemble because of its complex repeat structure that includes long palindromes, tandem repeats and segmental duplications1-3. As a result, more than half of the Y chromosome is missing from the GRCh38 reference sequence and it remains the last human chromosome to be finished4,5. Here, the Telomere-to-Telomere (T2T) consortium presents the complete 62,460,029-base-pair sequence of a human Y chromosome from the HG002 genome (T2T-Y) that corrects multiple errors in GRCh38-Y and adds over 30 million base pairs of sequence to the reference, showing the complete ampliconic structures of gene families TSPY, DAZ and RBMY; 41 additional protein-coding genes, mostly from the TSPY family; and an alternating pattern of human satellite 1 and 3 blocks in the heterochromatic Yq12 region. We have combined T2T-Y with a previous assembly of the CHM13 genome4 and mapped available population variation, clinical variants and functional genomics data to produce a complete and comprehensive reference sequence for all 24 human chromosomes.