key: cord-0686657-srexftmg authors: Brown, Hilary K.; Saha, Sudipta; Chan, Timothy C.Y.; Cheung, Angela M.; Fralick, Michael; Ghassemi, Marzyeh; Herridge, Margaret; Kwan, Janice; Rawal, Shail; Rosella, Laura; Tang, Terence; Weinerman, Adina; Lunsky, Yona; Razak, Fahad; Verma, Amol A. title: Outcomes in patients with and without disability admitted to hospital with COVID-19: a retrospective cohort study date: 2022-01-31 journal: CMAJ DOI: 10.1503/cmaj.211277 sha: da5737f07e665235d26d792eec4cc27beeae3b33 doc_id: 686657 cord_uid: srexftmg BACKGROUND: Disability-related considerations have largely been absent from the COVID-19 response, despite evidence that people with disabilities are at elevated risk for acquiring COVID-19. We evaluated clinical outcomes in patients who were admitted to hospital with COVID-19 with a disability compared with patients without a disability. METHODS: We conducted a retrospective cohort study that included adults with COVID-19 who were admitted to hospital and discharged between Jan. 1, 2020, and Nov. 30, 2020, at 7 hospitals in Ontario, Canada. We compared in-hospital death, admission to the intensive care unit (ICU), hospital length of stay and unplanned 30-day readmission among patients with and without a physical disability, hearing or vision impairment, traumatic brain injury, or intellectual or developmental disability, overall and stratified by age (≤ 64 and ≥ 65 yr) using multivariable regression, controlling for sex, residence in a long-term care facility and comorbidity. RESULTS: Among 1279 admissions to hospital for COVID-19, 22.3% had a disability. We found that patients with a disability were more likely to die than those without a disability (28.1% v. 17.6%), had longer hospital stays (median 13.9 v. 7.8 d) and more readmissions (17.6% v. 7.9%), but had lower ICU admission rates (22.5% v. 28.3%). After adjustment, there were no statistically significant differences between those with and without disabilities for in-hospital death or admission to ICU. After adjustment, patients with a disability had longer hospital stays (rate ratio 1.36, 95% confidence interval [CI] 1.19–1.56) and greater risk of readmission (relative risk 1.77, 95% CI 1.14–2.75). In age-stratified analyses, we observed longer hospital stays among patients with a disability than in those without, in both younger and older subgroups; readmission risk was driven by younger patients with a disability. INTERPRETATION: Patients with a disability who were admitted to hospital with COVID-19 had longer stays and elevated readmission risk than those without disabilities. Disability-related needs should be addressed to support these patients in hospital and after discharge. We conducted a retrospective cohort study that included adults with COVID-19 who were admitted to hospital and discharged between Jan. 1, 2020, and Nov. 30, 2020, at 7 hospitals in Ontario, Canada. We compared in-hospital death, admission to the intensive care unit (ICU), hospital length of stay and unplanned 30-day readmission among patients with and without a physical disability, hearing or vision impairment, traumatic brain injury, or intellectual or developmental disability, overall and stratified by age (≤ 64 and ≥ 65 yr) using multivariable regression, controlling for sex, residence in a long-term care facility and comorbidity. Results: Among 1279 admissions to hospital for COVID- 19, 22 .3% had a disability. We found that patients with a disability were more likely to die than those without a disability (28.1% v. 17 .6%), had longer hospital stays (median 13.9 v. 7.8 d) and more readmissions (17.6% v. 7.9%), but had lower ICU admission rates (22. 5% v. 28.3%). After adjustment, there were no statistically significant differences between those with and without disabilities for in-hospital death or admission to ICU. After adjustment, patients with a disability had longer hospital stays (rate ratio 1.36, 95% confidence interval [CI] 1. 19-1.56 ) and greater risk of readmission (relative risk 1.77, 95% CI 1.14-2.75). In age-stratified analyses, we observed longer hospital stays among patients with a disability than in those without, in both younger and older subgroups; readmission risk was driven by younger patients with a disability. health rules. Once they acquire SARS-CoV-2 infection, people with disabilities may be at risk for severe outcomes because they have elevated rates of comorbidities. 10 Some disabilities (e.g., spinal cord injuries and neurologic disabilities) result in physiologic changes that increase vulnerability to respiratory diseases and may mask symptoms of acute respiratory disease, which may delay diagnosis. [11] [12] [13] There have also been reports of barriers to high-quality hospital care for patients with disabilities who have COVID-19, including communication issues caused by the use of masks and restricted access to support persons. [14] [15] [16] [17] Some studies have suggested that patients with disabilities and COVID-19 are at elevated risk for severe disease and death, with most evaluating intellectual or developmental disability. 13, [18] [19] [20] [21] [22] [23] [24] [25] [26] Yet, consideration of disability-related needs has largely been absent from the COVID-19 response, with vaccine eligibility driven primarily by age and medical comorbidity, limited accommodations made for patients with disabilities who are in hospital, and disability data often not being captured in surveillance programs. [14] [15] [16] [17] To inform equitable pandemic supports, there is a need for data on patients with a broad range of disabilities who have COVID-19. We sought to evaluate standard clinical outcomes in patients admitted to hospital with COVID-19 27 (i.e., inhospital death, intensive care unit [ICU] admission, hospital length of stay and unplanned 30-d readmission) for patients with and without a disability, overall and stratified by age. We hypothesized that patients with a disability would have worse outcomes because of a greater prevalence of comorbidities, 10 physiologic characteristics that increase morbidity risk [11] [12] [13] and barriers to high-quality hospital care. 14-17 We conducted a retrospective cohort study using data from 5 academic and 2 community-based teaching hospitals in Toronto and Mississauga, Ontario, Canada, that are part of GEMINI, a hospital research collaborative. 28 Data were collected from clinical and administrative information systems by GEMINI. 29 Key data elements have 98%-100% accuracy compared with medical record review done manually. 29 Data included demographics, diagnoses, vital signs, laboratory test results and use of hospital resources. We included adults 18 years of age or older with COVID-19 who were admitted to an inpatient medical service (e.g., general medicine or respirology) or medical-surgical ICU and discharged between Jan. 1 and Nov. 30, 2020 (at 3 of the hospitals, data were available only from Jan. 1 to July 31, 2020). We identified COVID-19 diagnoses using International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10-CA) codes U07.1 and U07.2, 27,30 with U07.1 having 98% sensitivity, 99% specificity and 92% positive predictive value for COVID-19 detection compared with results for polymerase chain reaction (PCR) tests. 31 We identified a disability using published algorithms to ascertain physical disability, 32 hearing and vision impairments, 33, 34 traumatic brain injury 35 and intellectual or developmental disability 36, 37 in administrative data (Table 1) . These algorithms include diagnoses associated with need for accommodations when accessing health care, 32 functional limitations 37, 38 and adverse health outcomes. 39 Other similar algorithms have shown a specificity of 100% and positive predictive value of 80% compared with data from disability service providers. 40 We considered dementia and psychiatric disorders as comorbidities rather than including them as part of the "disability" definition because both are strong risk factors for death from COVID-19 41, 42 and are common in some groups with disability. 43, 44 We considered disability to be present if 1 or more disability diagnoses were recorded in the index hospital admission or any previous admission to a general medicine service at 1 of the GEMINI hospitals after Apr. 1, 2010 (the beginning of the GEMINI database; before 2019, GEMINI collected data only on general medicine admissions). We chose outcomes that were standard clinical indicators of severe COVID-19 outcomes among patients admitted to hospital: in-hospital death, ICU admission, total length of hospital stay and unplanned readmission to a medical service or medical-surgical ICU at any GEMINI hospital within 30 days of discharge but excluding interfacility transfers. 27 We considered readmissions to be unplanned if they occurred through an emergency department. We measured age, sex, transfer from an acute care hospital, longterm care facility residence and comorbidity, which we ascertained through specific conditions (i.e., chronic obstructive pulmonary disease, coronary artery disease, dementia, diabetes mellitus, heart failure, hypertension and psychiatric disorders) using the Clinical Classification Software Refined (Agency for Healthcare Research and Quality) 45 and via the Charlson Comorbidity Index. 46 We used postal codes to ascertain neighbourhoodlevel income and visible minority quintiles (Postal Code OM Conversion File Plus, Statistics Canada; www150.statcan.gc.ca/n1/en/ catalogue /82F0086X). 47 49 ). We reported baseline characteristics, vital signs, laboratory test results and mortality prediction scores at admission of patients admitted to hospital with COVID-19 with and without a disability using descriptive statistics and compared them using standardized differences. 50 We modelled in-hospital death, ICU admission and unplanned 30-day readmission using modified Poisson regression, 51 which uses a robust error variance to estimate relative risks (RRs). We used negative binomial regression, which estimates rate ratios, to model length of hospital stay. Since age is a strong predictor of disability 6 and adverse COVID-19 outcomes, 3 we derived overall models and models in patients 64 years of age or younger and 65 years or older separately. We selected this age threshold because risk of death associated with COVID-19 is elevated in patients who are older than 65 years of age 3 and Ontario residents become eligible for Old Age Security pension and the Ontario Drug Benefit at this age. We created the following sequential models that were adjusted for confounders: age, sex and residence in long-term care; 1-4,7-10 model 1 variables and medical comorbidity, dementia and psychiatric disorders (although these are correlated with disability, 10,43,44 we wanted to isolate risk associated with disability from that associated with chronic illness broadly); model 2 variables and predicted mortality risk using mAPACHE scores; and model 3 variables and neighbourhood-level income and visible minority quintiles (for overall models only, because these could accommodate more variables). In additional analyses, we stratified overall models by sex; described overall outcomes by type of disability (physical only, hearing or vision only, traumatic brain injury, or intellectual or developmental only and multiple); re-ran overall models, including dementia, in our disability definition; and re-ran overall models while also controlling for the number of previous hospital admissions over the study period. We performed all analyses using R version 4.0.2 (https://www.R-project.org/). We obtained approval from the research ethics board at each participating site. Between Jan. 1 patients with a disability, 212 (74.4%) had a physical disability, 18 (6.3%) had a hearing or vision impairment, 24 (8.4%) had a traumatic brain injury or intellectual or developmental disability and 31 (10.9%) had multiple disabilities. We found that patients with a disability were older than those without a disability, were less likely to be male, and were more likely to be residents of long-term care facilities and have comorbidities ( Table 2) . Patients with disabilities also had higher baseline predicted risk of death (Appendix 1, Table S1 , available at www.cmaj.ca/lookup/ doi/10.1503/cmaj.211277/tab-related-content). In unadjusted analyses, we found that patients with disabilities were more likely to die in hospital than those without disabilities ( Figure 1 ). We found that admission rates to the ICU were lower in patients with disabilities than those without disabilities (22.5% v. 28.3%) but found no significant differences in rates after adjustment overall (RR 1.00, 95% CI 0.75-1. 33) We found no differences in these results after further adjustment for predicted risk of death at admission (Figure 3) . Patients with disabilities were more likely to have unplanned 30-day readmissions than those without disabilities (17.6% v. 7.9%; RR 2.03, 95% CI 1.32-3.12), with the risk remaining elevated after we adjusted for age, sex, long-term care facility residence, medical comorbidity, dementia and psychiatric disorders (RR 1.77, 95% CI 1.14-2.75). After stratification by age, we found that the risk of unplanned 30-day admissions was greater in patients with disabilities than those without disabilities who were 64 years of age or younger (RR 2.85, 95% CI 1.51-5.35) but not in those who were 65 years of age or older (RR 1.02, 95% CI 0.54-1.93). We found no differences in these results after further adjustment for predicted risk of death at admission (Figure 4) . In sex-stratified analyses, unplanned readmission risk was higher among males with disabilities than males without disabilities (RR 1.78, 95% CI 1.02-3.08), but this difference was not observed among females. Results for other outcomes were consistent when analyzing both males and females separately (Appendix 1, Table S2 and Table S3 ). Hospital stays were longer among both males and females with disabilities than those without disabilities (Appendix 1, Table S3 ). Outcomes by type of disability showed highest risks for poor outcomes among patients with traumatic brain injury or intellectual or developmental disabilities, or multiple disabilities (Appendix 1, Table S4 ). We found no changes after we included dementia in our disability definition (Appendix 1, Table S5 and Table S6 ) and after controlling for number of previous hospital admissions (Appendix 1, Figure 1 : Risk of death among patients with and without a disability who were admitted to hospital with COVID-19. We adjusted all models for hospital site as a fixed effect. Model 1 was further adjusted for age, sex and residence in a long-term care facility. Model 2 was further adjusted for medical comorbidity, dementia and psychiatric disorders. Model 3 was further adjusted for predicted risk of death at presentation to hospital. Model 4 was further adjusted for neighbourhood-level income and proportions of patients who identified as a visible minority. Note: CI = confidence interval, RR = relative risk. We found that patients with disabilities who were admitted to hospital with COVID-19 had longer hospital stays and an elevated risk of unplanned 30-day readmission than patients without disabilities. These risks were not explained by sociodemographic factors, comorbidities or illness severity at baseline, although patients with disabilities had a greater predicted risk of death. The greater risk of 30-day readmission for patients with disabilities was mainly driven by patients younger than 65 years of age. Although we found no significant differences in hospital deaths or ICU admission after adjustment, it should be noted that the confidence intervals are wide and do not preclude a meaningful increase in risk that might be detected in a larger sample. Our findings suggest disability-related needs should be included in plans for COVID-19 response, in particular to support patients in hospital and to plan postdischarge supports, incuding community supports, to reduce risk of readmission to hospital. Several population-based studies have evaluated COVID-19 mortality in people with disabilities. 13, [18] [19] [20] [21] [22] [23] [24] [25] [26] An ecological study conducted in the United States showed that counties with a higher prevalence of disability had higher mortality rates, 18 and a retrospective cohort study in England that used census and mortality data reported that people with disabilities made up 58% of deaths. 19 A 2020 retrospective study involving 576 patients with neurologic disabilities reported higher case-fatality rates, 13 as did studies in the United Kingdom 20-23 and US 24-26 that involved patients with intellectual or developmental disabilities. We found no elevated risk of death in patients with disabilities in our cohort after adjustment. This difference from previous studies could be due to our adjustment for a wider range of covariates. 18, [22] [23] [24] [25] [26] Most of these studies evaluated overall risk of death rather than in patients admitted to hospital. [18] [19] [20] [21] [22] [23] [24] [25] Our sample population of patients in hospital, which was dominated by older, less healthy people, had a higher baseline mortality risk, making it less likely to detect differences between patients with and without disabilities. A 2020 study conducted in the US showed that disparities in case-fatality rates were larger in young patients with disabilities compared with those without intellectual or developmental disabilities. 26 This is similar to our finding that disparities in unplanned readmission were more pronounced in younger patients. Our findings are also consistent with data obtained for other conditions (e.g., pneumonia) that showed that patients with disabilities were at elevated risk for poor outcomes. 52, 53 Our data show that disability, along with older age and medical comorbidities -also known risk factors for poor outcomes among patients with other acute conditions 54 -should be a priority target for support strategies for COVID-19. We expected worse COVID-19 outcomes in patients with disabil ities given higher rates of comorbidity, 10 physiologic changes related to some disabilities, 11, 13 and the correlation between age and disability. 5, 6 Longer hospital stays and higher risk of readmission among patients with disabilities may reflect slower recovery and increased vulnerability to recurrent illness because of physiologic differences. [11] [12] [13] Figure 2 : Risk of admission to the intensive care unit among patients with and without a disability who were admitted to hospital with COVID-19. We adjusted all models for hospital site as a fixed effect. Model 1 was further adjusted for age, sex and residence in a long-term care facility. Model 2 was further adjusted for medical comorbidity, dementia and psychiatric disorders. Model 3 was further adjusted for predicted risk of death at presentation to hospital. Model 4 was further adjusted for neighbourhood-level income and proportions of patients who identified as a visible minority. Note: CI = confidence interval, RR = relative risk. Studies should evaluate whether disparities reflect gaps in high-quality care for patients with disabilities. For example, communication failures contribute to patient harm, 55, 56 and pandemic conditions may have hindered communication more for patients with disabilities. Hospitals had restricted visitor policies that limited access for support persons who would ordinarily assist with communication. 15 Facemasks and face shields also impede communication and may have a greater impact on people with disabilities. 15 Pandemic restrictions have also affected access to outpatient clinical, interprofessional, personal care, meal and medication services for people with disabilities. 57, 58 These disruptions have had a profound impact on the physical, mental and social well-being of people with disabilities, 59, 60 and may contribute to readmission risk. The differential impact of disability at younger ages is notable. In younger groups, persons without a disability have higher baseline functioning, which results in a greater detectable difference in risk for poor outcomes. 26 In older groups, differences between those with and without disabilities may be less pronounced because of greater comorbidity, frailty and physiologic changes related to aging at baseline. 26 Our findings underscore the importance of prioritizing people with disabilities for COVID-19 vaccination. Vaccination is critical for preventing COVID-19 infection, admission to hospital and adverse clinical outcomes among patients with disabilities admitted to hospital. People with disabilities continue to experience barriers to vaccination access. 61 Some groups of patients with disabilities, however, are at heightened risk for COVID-19 breakthrough infections and for adverse outcomes including hospital admission and death, even after being fully vaccinated. 62 Because our data were abstracted from 7 large urban or suburban hospitals, our findings may not be generalizable to other settings. However, our previous research 27, 28 showed that our cohort is similar to cohorts in studies conducted in the US and UK, 63, 64 and our data represent nearly 25% of contemporaneous COVID-19 hospital admissions in Ontario. 27 A strength of our study is that we were able to identify disability from 11 years of data rather than in the index hospital record only. 65 However, we were limited to a medical model of disability that relies on diagnoses rather than self-reported disability. We may have missed patients with undiagnosed disabilities or whose disabilities were not recorded for a hospital admission in a general medical service at one of the participating hospitals. However, any misclassification of patients with disabilities as not having a disability would likely result in underestimation of the risks, which means that the Figure 3 : Length of hospital stay among patients with and without a disability who were admitted to hospital with COVID-19. We adjusted all models for hospital site as a fixed effect. Model 1 was further adjusted for age, sex and residence in a long-term care facility. Model 2 was further adjusted for med ical comorbidity, dementia and psychiatric disorders. Model 3 was further adjusted for predicted risk of death at presentation to hospital. Model 4 was further adjusted for neighbourhood-level income and proportions of patients who identified as a visible minority. Note: CI = confidence interval , IQR = interquartile range. results reported herein are conservative. On the other hand, disability-related diagnoses vary in their impact on each person. 65 This issue relates to the intersection of disability with chronic illness, some of which reflects aging. 43 However, we stratified models by age and adjusted for comorbidity. Our sample size was not sufficient to evaluate outcomes in patients with specific disabilities separately beyond descriptive analyses. We were also unable to include all covariates at once in the age-stratified multivariable models, given the smaller sample sizes available for these analyses. There may be a risk of type 1 error, given the number of comparisons. Although we adjusted for the most important predictors of poor outcomes for COVID-19, 66 we did not have data on obesity or smoking, which are more common in people with disabilities, 67 and income and ethnicity were measurable only at the neighbourhood level. We were able to capture readmissions only to GEMINI hospitals; however, more than 80% of readmissions in our region go to the original hospital of admission. 68 We may have missed some patients with COVID-19 who were admitted to hospital for nonmedical reasons and were not cared for by a medical service or in an ICU, but the number of patients is likely small. Finally, the COVID-19 pandemic and response continue to rapidly evolve; our data reflect experiences during the first 2 major waves of the pandemic in Ontario, but the nature of the observed disparities may change as the pandemic progresses. Our findings highlight the importance of a pandemic response that prioritizes the needs of patients with disabilities who have COVID-19, particularly when they are in hospital and after their hospital stay. For patients with sensory, intellectual or developmental disabilities especially, accommodations should be prioritized for those requiring support persons to assist with communication. Training for clinicians about the needs and rights of people with disabilities may also be useful. Higher unplanned readmission rates underscore the importance of a patient-oriented discharge process that helps patients plan how to manage at home with safe options for assistance with personal care. Our findings also show the need to include disability-related data in COVID-19 surveillance to track outcomes of COVID-19 prevention and intervention strategies. Future research should also evaluate the intersection of disability with gender, experiences of racism and other social determinants of health, which may further affect COVID-19 outcomes. Such efforts should be prioritized in the pandemic response to ensure equitable care for patients with disabilities who have COVID-19. We adjusted all models for hospital site as a fixed effect. Model 1 was further adjusted for age, sex and residence in a long-term care facility. 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