Measuring waning protection from seasonal influenza vaccination during nine influenza seasons, Ontario, Canada, 2010/11 to 2018/19.

BackgroundWaning immunity from seasonal influenza vaccination can cause suboptimal protection during peak influenza activity. However, vaccine effectiveness studies assessing waning immunity using vaccinated and unvaccinated individuals are subject to biases.AimWe examined the association between time since vaccination and laboratory-confirmed influenza to assess the change in influenza vaccine protection over time.MethodsUsing linked laboratory and health administrative databases in Ontario, Canada, we identified community-dwelling individuals aged ≥ 6 months who received an influenza vaccine before being tested for influenza by RT-PCR during the 2010/11 to 2018/19 influenza seasons. We estimated the adjusted odds ratio (aOR) for laboratory-confirmed influenza by time since vaccination (categorised into intervals) and for every 28 days.ResultsThere were 53,065 individuals who were vaccinated before testing for influenza, with 10,264 (19%) influenza-positive cases. The odds of influenza increased from 1.05 (95% CI: 0.91-1.22) at 42-69 days after vaccination and peaked at 1.27 (95% CI: 1.04-1.55) at 126-153 days when compared with the reference interval (14-41 days). This corresponded to 1.09-times increased odds of influenza every 28 days (aOR = 1.09; 95% CI: 1.04-1.15). Individuals aged 18-64 years showed the greatest decline in protection against influenza A(H1N1) (aORper 28 days = 1.26; 95% CI: 0.97-1.64), whereas for individuals aged ≥ 65 years, it was against influenza A(H3N2) (aORper 28 days = 1.20; 95% CI: 1.08-1.33). We did not observe evidence of waning vaccine protection for individuals aged < 18 years.ConclusionsInfluenza vaccine protection wanes during an influenza season. Understanding the optimal timing of vaccination could ensure robust protection during seasonal influenza activity.

Sickle cell disease in Ontario, Canada: an epidemiologic profile based on health administrative data.

BACKGROUND: The number of patients with sickle cell disease in Ontario, Canada, is unknown. In the absence of a formal registry, we performed a study to determine an approximate census via analysis of health administrative databases. METHODS: We identified Ontario patients with a diagnosis of sickle cell disease through queries of the Discharge Abstract Database, National Ambulatory Care Reporting System and Newborn Screening Ontario database. The period of inquiry was Apr. 1, 2007, through Mar. 31, 2017. We identified repeat interactions by the same patient by cross-referencing provincial health insurance plan numbers. RESULTS: We documented health care system interactions for 3418 unique patients (1912 [55.9%] female, median age at the time of identification 24 yr). Over the 10-year study period, patients visited the emergency department a median of 2 (interquartile range [IQR] 1-7) times and an average of 6.69 (standard deviation [SD] 26.71) times, and were admitted to hospital a median of 1 (IQR 1-5) time and an average of 4.38 (SD 8.53) times for treatment related to sickle cell disease. A total of 229 patients (6.7%) died during the study period, with an average age at death of 55 years. Even without accounting for the effects of immigration, the rate of natural increase slowed slightly over the study period owing to a decrease in the annual number of affected births. INTERPRETATION: The estimated prevalence of patients with sickle cell disease in Ontario in 2007/08-2016/17 was 1 in 4200, and affected patients' need for hospital-based care was substantial, although highly variable. Similar queries of health administrative databases may be feasible in other Canadian provinces.

Evaluating the Impact of Statin Use on Influenza Vaccine Effectiveness and Influenza Infection in Older Adults.

BACKGROUND: Older adults are recommended to receive influenza vaccination annually, and many use statins. Statins have immunomodulatory properties that might modify influenza vaccine effectiveness (VE) and alter influenza infection risk. METHODS: Using the test-negative design and linked laboratory and health administrative databases in Ontario, Canada, we estimated VE against laboratory-confirmed influenza among community-dwelling statin users and nonusers aged ≥66 years during the 2010-2011 to 2018-2019 influenza seasons. We also estimated the odds ratio for influenza infection comparing statin users and nonusers by vaccination status. RESULTS: Among persons tested for influenza across the 9 seasons, 54 243 had continuous statin exposure before testing and 48 469 were deemed unexposed. The VE against laboratory-confirmed influenza was similar between statin users and nonusers (17% [95% confidence interval, 13%-20%] and 17% [13%-21%] respectively; test for interaction, P = .87). In both vaccinated and unvaccinated persons, statin users had higher odds of laboratory-confirmed influenza than nonusers (odds ratios for vaccinated and unvaccinated persons 1.15 [95% confidence interval, 1.10-1.21] and 1.15 [1.10-1.20], respectively). These findings were consistent by mean daily dose and statin type. VE did not differ between users and nonusers of other cardiovascular drugs, except for ß-blockers. We did not observe that vaccinated and unvaccinated users of these drugs had increased odds of influenza, except for unvaccinated ß-blocker users. CONCLUSIONS: Influenza VE did not differ between statin users and nonusers. Statin use was associated with increased odds of laboratory-confirmed influenza in vaccinated and unvaccinated persons, but these associations might be affected by residual confounding.

Trends and correlates of concurrent opioid and benzodiazepine and/or gabapentinoid use among Ontario nursing home residents.

BACKGROUND: A concern with long-term opioid use is the increased risk arising when opioids are used concurrently with drugs that can potentiate their associated adverse effects. The drugs most often encountered are benzodiazepines (BZDs) and gabapentinoids. Our study objectives were to examine trends in the concurrent use of opioids and BZDs, or gabapentinoids, in a Canadian nursing home population over an 11-year period, and current resident-level correlates of this concurrent use. METHODS: We conducted a population-based, repeated cross-sectional study among Ontario nursing home residents (>65 years) dispensed opioids between April 2009 and February 2020. For the last study year, we examined cross-sectional associations between resident characteristics and concurrent use of opioids with BZDs or gabapentinoids. Linked data on nursing home residents from clinical and health administrative databases was used. The yearly proportions of residents who were dispensed an opioid concurrently with a BZD or gabapentinoid were plotted with percent change derived from log-binomial regression models. Separate modified Poisson regression models estimated resident-level correlates of concurrent use of opioids with BZDs or gabapentinoids. RESULTS: Over the study period, among residents dispensed an opioid there was a 53.2% relative decrease (30.7% to 14.4%) in concurrent BZD and a 505.4% relative increase (4.4% to 26.6%) in concurrent gabapentinoid use. In adjusted models, increasing age and worsening cognition were inversely associated with the concurrent use of both classes, but most other significantly related covariates were unique to each drug class (e.g., sex and anxiety disorders for BZD, pain severity and presence of pain-related conditions for gabapentinoids). CONCLUSIONS: Co-administration of BZDs or gabapentinoids in Ontario nursing home residents dispensed opioids remains common, but the pattern of co-use has changed over time. Observed covariates of concurrent use in 2019/20 suggest distinct but overlapping resident populations requiring consideration of the relative risks versus benefits of this co-use and monitoring for potential harm.

Patterns of diabetes testing for older adults without diabetes in Ontario's nursing homes: A population-based study.

BACKGROUND: Asymptomatic diabetes testing may be of limited value for older nursing home residents, but most diabetes guidelines lack upper-age cutoffs for screening cessation. We evaluated patterns of glycated hemoglobin (HbA1c) and serum blood glucose (SBG) testing among older residents without diabetes in Ontario, Canada. METHODS: This population-based retrospective cohort study used provincial health administrative data from ICES to identify older nursing home residents in Ontario without diabetes between January 1, 2015 and December 31, 2018. We examined HbA1c and glucose testing rates overall, by age, sex, and near end-of-life. The number of tests needed to identify one case of diabetes (using HbA1c thresholds of 6.5% and 8.0%) were also calculated. RESULTS: Among 102,923 older nursing home residents (70.3% women; average age 85.6 ± SD 7.7 years), 46.1% of residents received ≥1 HbA1c test over an average follow-up period of 2.15 (± SD 1.49) years, and 18.2% of these tested residents received ≥4 HbA1c tests. The crude HbA1c testing rate was 52.6 tests/100 person-years (95% CI 52.3-52.9). Testing rates among residents aged ≥80 years was 50.7 HbA1c tests/100 person-years (95% CI 50.4-51.0), and 47.8 tests/100 person-years (95% CI 46.5-49.0) among residents near end-of-life. The number of tests to identify a case of diabetes (HbA1c ≥ 6.5%) was 44, while the number of tests to identify a case of actionable diabetes (HbA1c ≥ 8%) was 310. Less than 1% of residents with an HbA1c test met criteria for actionable diabetes. CONCLUSIONS: Nursing home residents without diabetes receive frequent diabetes testing, with high testing rates even in residents over 80 years old and residents near end-of-life. The high number of tests needed to identify a case of actionable diabetes highlights the urgent need to re-evaluate diabetes testing practices in nursing homes.

Association of Influenza Vaccination With SARS-CoV-2 Infection and Associated Hospitalization and Mortality Among Patients Aged 66 Years or Older.

Importance: Vaccine effectiveness studies have rarely implemented strategies to reduce the healthy vaccinee bias arising from differences in health care-seeking behavior between vaccinated and unvaccinated individuals. Although previous observational studies suggest that influenza vaccination is associated with a reduced risk of SARS-CoV-2-associated outcomes, the healthy vaccinee bias may have led to overestimating the vaccination effect. Objective: To estimate the association between influenza vaccination and SARS-CoV-2-associated outcomes. Design, Setting, and Participants: This cohort study was conducted over 2 consecutive influenza vaccination campaigns (2019-2020 and 2020-2021), owing to the substantial COVID-19 burden and the greater validity of influenza vaccination data in the studied age group. The study population included community-dwelling adults aged 66 years or older in Ontario, Canada. Exposure: Influenza vaccination for a given season. Main Outcomes and Measures: The outcomes of interest included SARS-CoV-2 infection, SARS-CoV-2-associated hospitalization, SARS-CoV-2-associated death, and a composite of SARS-CoV-2-associated hospitalization or death. Cox proportional hazards models were used to measure the association between influenza vaccination and SARS-CoV-2-associated outcomes, censoring individuals who moved into long-term care, received COVID-19 vaccines, or died before the observation period end date. Primary care periodic health examinations (PHEs) were explored as a negative tracer exposure (ie, no association expected with SARS-CoV-2 outcomes) and as an effect modifier of the association between influenza vaccination and SARS-CoV-2 outcomes. Results: Of 2 922 449 individuals aged 66 years or older (54.2% female) living in Ontario, 2 279 805 were included in the study. Among these, 1 234 647 (54.2%) were female and 1 045 158 (45.8%) were male; their mean (SD) age was 75.08 (7.21) years. Those who had received influenza vaccination exhibited a lower incidence of SARS-CoV-2 infection than unvaccinated individuals for the 2019-2020 cohort (adjusted hazards ratio [aHR], 0.78; 95% CI, 0.73-0.84) and the 2020-2021 cohort (aHR, 0.76; 95% CI, 0.74-0.78). This association was also observed for SARS-CoV-2-associated hospitalization or death (2019-2020: aHR, 0.83; 95% CI, 0.74-0.92; 2020-2021: aHR, 0.66; 95% CI, 0.63-0.70). Similarly, undergoing a PHE was also associated with a lower incidence of SARS-CoV-2 infection (aHR, 0.85; 95% CI, 0.78-0.91) and SARS-CoV-2-associated hospitalization or death (aHR, 0.80; 95% CI, 0.70-0.90), and modified the association between influenza vaccination and SARS-CoV-2 infection for vaccinated individuals who underwent PHE (aHR, 0.62; 95% CI, 0.52-0.74) and for vaccinated individuals who did not undergo PHE (aHR, 0.81; 95% CI, 0.76-0.87), and also SARS-CoV-2-associated hospitalization or death in vaccinated individuals who underwent PHE (aHR, 0.66; 95% CI, 0.49-0.88) and vaccinated individuals who did not undergo PHE (aHR, 0.85, 95% CI, 0.76-0.95). Conclusions and Relevance: The findings of this cohort study suggest that undergoing a PHE may at least partially modify the association between influenza vaccination and SARS-CoV-2-associated outcomes in individuals aged 66 years or older, providing evidence of the healthy vaccinee bias that may affect vaccine effectiveness studies.

Correlates of Opioid Use Among Ontario Long-Term Care Residents and Variation by Pain Frequency and Intensity: A Cross-sectional Analysis.

BACKGROUND: Chronic non-cancer pain is common among older residents of long-term care (LTC) homes and often poorly recognized and treated. With heightened concerns regarding opioid prescribing in recent years, it is important to examine the current prevalence of opioid use and its association with resident characteristics to help identify those potentially at risk of medication harms as well as suboptimal pain management. OBJECTIVES: The aims were to estimate the prevalence and correlates of opioid use among non-palliative LTC residents and explore variation in opioid prevalence and correlates across strata defined by pain frequency and intensity. METHODS: We conducted a population-based cross-sectional study of all older (aged > 65 years) LTC residents (excluding those with cancer or receiving palliative care) in Ontario, Canada during 2018-2019. Health administrative databases were linked with standardized clinical assessment data to ascertain residents' health and pain characteristics and their opioid and other medication use. Modified Poisson regression models estimated unadjusted and adjusted associations between residents' characteristics and opioid use, overall and across strata capturing pain frequency and intensity. RESULTS: Among 75,020 eligible residents (mean age 85.1 years; 70% female), the prevalence of opioid use was 18.5% and pain was 29.4%. Opioid use ranged from 12.2% for residents with no current pain to 55.7% for those with severe pain. In adjusted models, residents newly admitted to LTC (adjusted risk ratio [aRR] = 0.60, 95% confidence interval [CI] 0.57-0.62) and with moderate to severe cognitive impairment (aRR = 0.69, 95% CI 0.66-0.72) or dementia (aRR = 0.76, 95% CI 0.74-0.79) were significantly less likely to receive an opioid, whereas residents with select conditions (e.g., arthritis, aRR = 1.37, 95% CI 1.32-1.41) and concurrently using gabapentinoids (aRR = 1.80, 95% CI 1.74-1.86), benzodiazepines (aRR = 1.33, 95% CI 1.28-1.38), or antidepressants (aRR = 1.31, 95% CI 1.27-1.35) were significantly more likely to receive an opioid. The associations observed for residents newly admitted, with dementia, and concurrently using gabapentinoids, benzodiazepines, or antidepressants were largely consistent across all pain strata. CONCLUSIONS: Our findings describe resident sub-groups at potentially higher risk of adverse health outcomes in relation to both opioid use and non-use. LTC clinical and policy changes informed by research are required to ensure the appropriate recognition and management of non-cancer pain in this setting.

Rates of health services use among residents of retirement homes in Ontario: a population-based cohort study.

BACKGROUND: Because there are no standardized reporting systems specific to residents of retirement homes in North America, little is known about the health of this distinct population of older adults. We evaluated rates of health services use by residents of retirement homes relative to those of residents of long-term care homes and other populations of older adults. METHODS: We conducted a retrospective cohort study using population health administrative data from 2018 on adults 65 years or older in Ontario. We matched the postal codes of individuals to those of licensed retirement homes to identify residents of retirement homes. Outcomes included rates of hospital-based care and physician visits. RESULTS: We identified 54 733 residents of 757 retirement homes (mean age 86.7 years, 69.0% female) and 2 354 385 residents of other settings. Compared to residents of long-term care homes, residents of retirement homes had significantly higher rates per 1000 person months of emergency department visits (10.62 v. 4.48, adjusted relative rate [RR] 2.61, 95% confidence interval [CI] 2.55 to 2.67), hospital admissions (5.42 v. 2.08, adjusted RR 2.77, 95% CI 2.71 to 2.82), alternate level of care (ALC) days (6.01 v. 2.96, adjusted RR 1.51, 95% CI 1.48 to 1.54), and specialist physician visits (6.27 v. 3.21, adjusted RR 1.64, 95% CI 1.61 to 1.68), but a significantly lower rate of primary care visits (16.71 v. 108.47, adjusted RR 0.13, 95% CI 0.13 to 0.14). INTERPRETATION: Residents of retirement homes are a distinct population with higher rates of hospital-based care. Our findings can help to inform policy debates about the need for more coordinated primary and supportive health care in privately operated congregate care homes.

Behavioral Nudges to Improve Audit and Feedback Report Opening Among Antibiotic Prescribers: A Randomized Controlled Trial.

Background: Peer comparison audit and feedback has demonstrated effectiveness in improving antibiotic prescribing practices, but only a minority of prescribers view their reports. We rigorously tested 3 behavioral nudging techniques delivered by email to improve report opening. Methods: We conducted a pragmatic randomized controlled trial among Ontario long-term care prescribers enrolled in an ongoing peer comparison audit and feedback program which includes data on their antibiotic prescribing patterns. Physicians were randomized to 1 of 8 possible sequences of intervention/control allocation to 3 different behavioral email nudges: a social peer comparison nudge (January 2020), a maintenance of professional certification incentive nudge (October 2020), and a prior participation nudge (January 2021). The primary outcome was feedback report opening; the primary analysis pooled the effects of all 3 nudging interventions. Results: The trial included 421 physicians caring for >28 000 residents at 450 facilities. In the pooled analysis, physicians opened only 29.6% of intervention and 23.9% of control reports (odds ratio [OR], 1.51 [95% confidence interval {CI}, 1.10-2.07], P = .011); this difference remained significant after accounting for physician characteristics and clustering (adjusted OR [aOR], 1.74 [95% CI, 1.24-2.45], P = .0014). Of individual nudging techniques, the prior participation nudge was associated with a significant increase in report opening (OR, 1.62 [95% CI, 1.06-2.47], P = .026; aOR, 2.16 [95% CI, 1.33-3.50], P = .0018). In the pooled analysis, nudges were also associated with accessing more report pages (aOR, 1.28 [95% CI, 1.14-1.43], P < .001). Conclusions: Enhanced nudging strategies modestly improved report opening, but more work is needed to optimize physician engagement with audit and feedback. Clinical Trials Registration: NCT04187742.

Hospitalizations During the COVID-19 Pandemic Among Recently Homeless Individuals: a Retrospective Population-Based Matched Cohort Study.

BACKGROUND: Hospitalizations fell precipitously among the general population during the COVID-19 pandemic. It remains unclear whether individuals experiencing homelessness experienced similar reductions. OBJECTIVE: To examine how overall and cause-specific hospitalizations changed among individuals with a recent history of homelessness (IRHH) and their housed counterparts during the first wave of the COVID-19 pandemic, using corresponding weeks in 2019 as a historical control. DESIGN: Population-based cohort study conducted in Ontario, Canada, between September 30, 2018, and September 26, 2020. PARTICIPANTS: In total, 38,617 IRHH, 15,022,368 housed individuals, and 186,858 low-income housed individuals matched on age, sex, rurality, and comorbidity burden. MAIN MEASURES: Primary outcomes included medical-surgical, non-elective (overall and cause-specific), elective surgical, and psychiatric hospital admissions. KEY RESULTS: Average rates of medical-surgical (rate ratio: 3.8, 95% CI: 3.7-3.8), non-elective (10.3, 95% CI: 10.1-10.4), and psychiatric admissions (128.1, 95% CI: 126.1-130.1) between January and September 2020 were substantially higher among IRHH compared to housed individuals. During the peak period (March 17 to June 16, 2020), rates of medical-surgical (0.47, 95% CI: 0.47-0.47), non-elective (0.80, 95% CI: 0.79-0.80), and psychiatric admissions (0.86, 95% CI: 0.84-0.88) were significantly lower among housed individuals relative to equivalent weeks in 2019. No significant changes were observed among IRHH. During the re-opening period (June 17-September 26, 2020), rates of non-elective hospitalizations for liver disease (1.41, 95% CI: 1.23-1.69), kidney disease (1.29, 95% CI: 1.14-1.47), and trauma (1.19, 95% CI: 1.07-1.32) increased substantially among IRHH but not housed individuals. Distinct hospitalization patterns were observed among IRHH even in comparison with more medically and socially vulnerable matched housed individuals. CONCLUSIONS: Persistence in overall hospital admissions and increases in non-elective hospitalizations for liver disease, kidney disease, and trauma indicate that the COVID-19 pandemic presented unique challenges for recently homeless individuals. Health systems must better address the needs of this population during public health crises.

Greater Opioid Use Among Nursing Home Residents in Ontario, Canada During the First 2 Waves of the COVID-19 Pandemic.

OBJECTIVES: To examine the association between the COVID-19 pandemic and opioid use among nursing home residents followed up to March 2021, and possible variation by dementia and frailty status. DESIGN: Population-based cohort study with an interrupted time series analysis. SETTING AND PARTICIPANTS: Linked health administrative databases for residents of all nursing homes (n = 630) in Ontario, Canada were examined. Residents were divided into consecutive weekly cohorts (first observation week was March 5 to 11, 2017 and last was March 21 to March 27, 2021). METHODS: The weekly proportion of residents dispensed an opioid was examined overall and by strata defined by the presence of dementia and frailty. Autoregressive Integrated Moving Average models with step and ramp intervention functions tested for immediate level and slope changes in weekly opioid use after the onset of the pandemic (March 1, 2020) and were fit on prepandemic data for projected trends. RESULTS: The average weekly cohort ranged from 76,834 residents (prepandemic) to 69,359 (pandemic period), with a consistent distribution by sex (69% female) and age (54% age 85 + years). There was a statistically significant increased slope change in the weekly proportion of residents dispensed opioids (parameter estimate (ß) = 0.035; standard error (SE) = 0.005, P < .001). Although significant for all 4 strata, the increased slope change was more pronounced among nonfrail residents (ß = 0.038; SE = 0.008, P < .001) and those without dementia (ß = 0.044; SE = 0.008, P < .001). The absolute difference in observed vs predicted opioid use in the last week of the pandemic period ranged from 1.25% (frail residents) to 2.28% (residents without dementia). CONCLUSIONS AND IMPLICATIONS: Among Ontario nursing home residents, there was a statistically significant increase in opioid dispensations following the onset of the pandemic that persisted up to 1 year later. Investigations of the reasons for increased use, potential for long-term use and associated health consequences for residents are warranted.

Drug Overdoses During the COVID-19 Pandemic Among Recently Homeless Individuals.

AIMS: To examine how weekly rates of emergency department (ED) visits for drug overdoses changed among individuals with a recent history of homelessness (IRHH) and their housed counterparts during the pre-pandemic, peak, and re-opening periods of the first wave of the COVID-19 pandemic, using corresponding weeks in 2019 as a historical control. DESIGN: Population-based retrospective cohort study conducted between September 30, 2018 and September 26, 2020. SETTING: Ontario, Canada. PARTICIPANTS: A total of 38 617 IRHH, 15 022 369 housed individuals, and 186 858 low-income housed individuals matched on age, sex, rurality, and comorbidity burden. MEASUREMENTS: ED visits for drug overdoses of accidental and undetermined intent. FINDINGS: Average rates of ED visits for drug overdoses between January and September 2020 were higher among IRHH compared with housed individuals (rate ratio [RR], 148.0; 95% CI, 142.7-153.5) and matched housed individuals (RR, 22.3; 95% CI, 20.7-24.0). ED visits for drug overdoses decreased across all groups by ~20% during the peak period (March 17 to June 16, 2020) compared with corresponding weeks in 2019. During the re-opening period (June 17 to September 26, 2020), rates of ED visits for drug overdoses were significantly higher among IRHH (RR, 1.56; 95% CI, 1.44-1.69), matched housed individuals (RR, 1.25; 95% CI, 1.08-1.46), and housed individuals relative to equivalent weeks in 2019 (RR, 1.07; 95% CI, 1.02-1.11). The relative increase in drug overdose ED visits among IRHH was larger compared with both matched housed individuals (P = 0.01 for interaction between group and year) and housed individuals (P < 0.001) during this period. CONCLUSIONS: Recently homeless individuals in Ontario, Canada experienced disproportionate increases in ED visits for drug overdoses during the re-opening period of the COVID-19 pandemic compared with housed people.

Comparison of Medication Prescribing Before and After the COVID-19 Pandemic Among Nursing Home Residents in Ontario, Canada.

Importance: COVID-19 has had devastating effects on the health and well-being of older adult residents and health care professionals in nursing homes. Uncertainty about the associated consequences of these adverse effects on the use of medications common to this care setting remains. Objective: To examine the association between the COVID-19 pandemic and prescription medication changes among nursing home residents. Design, Setting, and Participants: This population-based cohort study with an interrupted time-series analysis used linked health administrative data bases for residents of all nursing homes (N = 630) in Ontario, Canada. During the observation period, residents were divided into consecutive weekly cohorts. The first observation week was March 5 to 11, 2017; the last observation week was September 20 to 26, 2020. Exposures: Onset of the COVID-19 pandemic on March 1, 2020. Main Outcomes and Measures: Weekly proportion of residents dispensed antipsychotics, benzodiazepines, antidepressants, anticonvulsants, opioids, antibiotics, angiotensin receptor blockers (ARBs), and angiotensin-converting enzyme (ACE) inhibitors. Autoregressive integrated moving average models with step and ramp intervention functions tested for level and slope changes in weekly medication use after the onset of the pandemic and were fit on prepandemic data for projected trends. Results: Across study years, the annual cohort size ranged from 75 850 to 76 549 residents (mean [SD] age, 83.4 [10.8] years; mean proportion of women, 68.9%). A significant increased slope change in the weekly proportion of residents who were dispensed antipsychotics (parameter estimate [ß] = 0.051; standard error [SE] = 0.010; P < .001), benzodiazepines (ß = 0.026; SE = 0.003; P < .001), antidepressants (ß = 0.046; SE = 0.013; P < .001), trazodone hydrochloride (ß = 0.033; SE = 0.010; P < .001), anticonvulsants (ß = 0.014; SE = 0.006; P = .03), and opioids (ß = 0.038; SE = 0.007; P < .001) was observed. The absolute difference in observed vs estimated use in the last week of the pandemic period ranged from 0.48% (for anticonvulsants) to 1.52% (for antipsychotics). No significant level or slope changes were found for antibiotics, ARBs, or ACE inhibitors. Conclusions and Relevance: In this population-based cohort study, statistically significant increases in the use of antipsychotics, benzodiazepines, antidepressants, anticonvulsants, and opioids followed the onset of the COVID-19 pandemic, although absolute differences were small. There were no significant changes for antibiotics, ARBs, or ACE inhibitors. Studies are needed to monitor whether changes in pharmacotherapy persist, regress, or accelerate during the course of the pandemic and how these changes affect resident-level outcomes.

Preterm birth and stillbirth rates during the COVID-19 pandemic: a population-based cohort study.

BACKGROUND: Conflicting reports have emerged for rates of preterm births and stillbirths during the COVID-19 pandemic. Most of these reports did not account for natural variation in these rates. We aimed to evaluate variations in preterm birth and stillbirth rates before and during the COVID-19 pandemic in Ontario, Canada. METHODS: We conducted a retrospective cohort study using linked population health administrative databases of pregnant people giving birth in any hospital in Ontario between July 2002 and December 2020. We calculated preterm birth and stillbirth rates. We assessed preterm birth at 22-28, 29-32 and 33-36 weeks' gestation, and stillbirths at term and preterm gestation. We used Laney control P' charts for the 18-year study period (6-mo observation periods) and interrupted time-series analyses for monthly rates for the most recent 4 years. RESULTS: We evaluated 2 465 387 pregnancies, including 13 781 that resulted in stillbirth. The mean preterm birth rate for our cohort was 7.96% (range 7.32%-8.59%). From January to December 2020, we determined that the preterm birth rate in Ontario was 7.87%, with no special cause variation. The mean stillbirth rate for the cohort was 0.56% (range 0.48%-0.70%). From January to December 2020, the stillbirth rate was 0.53%, with no special cause variation. We did not find any special cause variation for preterm birth or stillbirth subgroups. We found no changes in slope or gap between prepandemic and pandemic periods using interrupted time-series analyses. INTERPRETATION: In Ontario, Canada, we found no special cause variation (unusual change) in preterm birth or stillbirth rates, overall or by subgroups, during the first 12 months of the COVID-19 pandemic compared with the previous 17.5 years.

Health services utilization prior to amyotrophic lateral sclerosis diagnosis: A province-wide study of individuals treated with riluzole in Ontario, Canada.

INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) symptoms mimic those of other conditions and often require multiple physician and healthcare contacts for investigation and accurate diagnosis. We examined the type and frequency of healthcare service utilization prior to ALS diagnosis and tracheostomy-free survival by sex and rurality among individuals treated with riluzole in Ontario, Canada. METHODS: This population-based cohort study used administrative databases to identify patients aged 18+ y diagnosed with ALS and started on riluzole between April 2002-March 2018. Using Poisson regression, rate ratios of healthcare utilization and atypical diagnostic tests and unnecessary therapeutic interventions 5 y prior to ALS diagnosis were compared by sex and rurality. Tracheostomy-free survival after diagnosis was compared between groups using Kaplan-Meier estimators and proportional hazards models. RESULTS: A total of 1071 patients with ALS were identified with a mean age of 70 y; 563 (52.6%) were men and 134 (12.5%) were rural residents. The number of physician visits increased in the 18 mo prior to ALS diagnosis. We observed modest sex differences in healthcare utilization. Rural patients had lower neurologist visit rates (rate ratio [RR], 0.78; 95% confidence interval [CI], 0.70-0.87) and were significantly more likely to receive an atypical diagnostic test or unnecessary therapeutic intervention (RR, 1.80; 95% CI, 1.04-3.10). Tracheostomy-free survival did not differ by sex (log-rank P-value = .78) or rurality (log-rank P-value = .84). DISCUSSION: Given disparities observed in healthcare of rural ALS patients, policy strategies are needed to ensure all patients have timely access to care along the pathway from symptom onset to ALS diagnosis, to enable access to new therapeutics and clinical trials.

Impact of Dementia on Patterns of Home Care After Inpatient Rehabilitation Discharge for Older Adults After Hip Fractures.

OBJECTIVE: To describe differences in home care use in the 30 days after discharge from inpatient rehabilitation after a hip fracture among older adults with dementia compared with those without dementia. DESIGN: Retrospective cohort study of individually linked health administrative data. SETTING: Community-dwelling older adults after discharge from inpatient rehabilitation facilities in Ontario, Canada. PARTICIPANTS: A total of 17,263 older adults (N=17,263), of whom 2489 had dementia (14.4%), who were treated for hip fracture in acute care and then admitted to inpatient rehabilitation facilities between January 1, 2011 and March 31, 2017. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The proportion receiving home care services and number of visits (physiotherapy, occupational therapy, nursing, personal/homemaking) in the 30 days after discharge were compared by dementia status with multivariate models, stratified by sex. RESULTS: Compared with those without dementia, adults with dementia were older, had lower functional scores, and were more likely to receive home care services in the 30 days after discharge from inpatient rehabilitation (87.0% vs 79.0%, P<.001), including personal/homemaking services (66.1% vs 46.4%, P<.001) and occupational therapy (45.3% vs 37.4, P<.001) but not physiotherapy (55.8% vs 56.2%, P=.677) or nursing (19.6% vs 18.7%, P=.268). After adjustment, older adults with dementia were more likely to receive home care in both men (odds ratio [OR] =2.01; 95% confidence interval [CI], 1.57-2.57) and women (OR=1.50; 95% CI, 1.30-1.74) as well as more services (rate ratio men=1.60; 95% CI, 1.44-1.79; rate ratio women=1.50; 95% CI, 1.41-1.60). CONCLUSIONS: Among older adults discharged from inpatient rehabilitation, older adults with dementia received home care services more often than older adults without dementia. However, irrespective of sex and dementia status, almost half of this population (44%) did not receive physiotherapy. We recommend that, resources permitting, all older adults receive physiotherapy to facilitate recovery.

Trends in Anticoagulant Use at Nursing Home Admission and Variation by Frailty and Chronic Kidney Disease Among Older Adults with Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) is relatively common among nursing home residents, and decisions regarding anticoagulant therapy in this setting may be complicated by resident frailty and other factors. OBJECTIVES: The aim of this study was to examine trends and correlates of oral anticoagulant use among newly admitted nursing home residents with AF following the approval of direct-acting oral anticoagulants (DOACs). METHODS: We conducted a retrospective cohort study of all adults aged > 65 years with AF who were newly admitted to nursing homes in Ontario, Canada, between 2011 and 2018 (N = 36,466). Health administrative databases were linked with comprehensive clinical assessment data captured shortly after admission, to ascertain resident characteristics. Trends in prevalence of anticoagulant use (any, warfarin, DOAC) at admission were captured with prescription claims and examined by frailty and chronic kidney disease (CKD). Log-binomial regression models estimated crude percentage changes in use over time and modified Poisson regression models assessed factors associated with anticoagulant use and type. RESULTS: The prevalence of anticoagulant use at admission increased from 41.1% in 2011/2012 to 58.0% in 2017/2018 (percentage increase = 41.1%, p < 0.001). Warfarin use declined (- 67.7%, p < 0.001), while DOAC use increased. Anticoagulant use was less likely among residents with a prior hospitalization for hemorrhagic stroke (adjusted risk ratio [aRR] 0.65, 95% confidence interval [CI] 0.60-0.70) or gastrointestinal bleed (aRR 0.80, 95% CI 0.78-0.83), liver disease (aRR 0.78, 95% CI 0.69-0.89), severe cognitive impairment (aRR 0.89, 95% CI 0.85-0.94), and non-steroidal anti-inflammatory drug (aRR 0.76, 95% CI 0.71-0.81) or antiplatelet (aRR 0.25, 95% CI 0.23-0.27) use, but more likely for those with a prior hospitalization for ischemic stroke or thromboembolism (aRR 1.30, 95% CI 1.27-1.33). CKD was associated with a reduced likelihood of DOAC versus warfarin use in both the early (aRR 0.62, 95% CI 0.54-0.71) and later years (aRR 0.79, 95% CI 0.76-0.83) of our study period. Frail residents were significantly less likely to receive an anticoagulant at admission, although this association was modest (aRR 0.95, 95% CI 0.92-0.98). Frailty was not associated with anticoagulant type. CONCLUSIONS: While the proportion of residents with AF receiving oral anticoagulants at admission increased following the approval of DOACs, over 40% remained untreated. Among those treated, use of a DOAC increased, while warfarin use declined. The impact of these recent treatment patterns on the balance between benefit and harm among residents warrant further investigation.

Population-Wide Peer Comparison Audit and Feedback to Reduce Antibiotic Initiation and Duration in Long-Term Care Facilities with Embedded Randomized Controlled Trial.

BACKGROUND: Antibiotic overprescribing in long-term care settings is driven by prescriber preferences and is associated with preventable harms for residents. We aimed to determine whether peer comparison audit and feedback reporting for physicians reduces antibiotic overprescribing among residents. METHODS: We employed a province wide, difference-in-differences study of antibiotic prescribing audit and feedback, with an embedded pragmatic randomized controlled trial (RCT) across all long-term care facilities in Ontario, Canada, in 2019. The study year included 1238 physicians caring for 96 185 residents. In total, 895 (72%) physicians received no feedback; 343 (28%) were enrolled to receive audit and feedback and randomized 1:1 to static or dynamic reports. The primary outcomes were proportion of residents initiated on an antibiotic and proportion of antibiotics prolonged beyond 7 days per quarter. RESULTS: Among all residents, between the first quarter of 2018 and last quarter of 2019, there were temporal declines in antibiotic initiation (28.4% to 21.3%) and prolonged duration (34.4% to 29.0%). Difference-in-differences analysis confirmed that feedback was associated with a greater decline in prolonged antibiotics (adjusted difference -2.65%, 95% confidence interval [CI]: -4.93 to -.28%, P = .026), but there was no significant difference in antibiotic initiation. The reduction in antibiotic durations was associated with 335 912 fewer days of treatment. The embedded RCT detected no differences in outcomes between the dynamic and static reports. CONCLUSIONS: Peer comparison audit and feedback is a pragmatic intervention that can generate small relative reductions in the use of antibiotics for prolonged durations that translate to large reductions in antibiotic days of treatment across populations. Clinical Trials Registration. NCT03807466.

Potential diabetes overtreatment and risk of adverse events among older adults in Ontario: a population-based study.

AIMS/HYPOTHESIS: More than 25% of older adults (age ≥75 years) have diabetes and may be at risk of adverse events related to treatment. The aim of this study was to assess the prevalence of intensive glycaemic control in this group, potential overtreatment among older adults and the impact of overtreatment on the risk of serious events. METHODS: We conducted a retrospective, population-based cohort study of community-dwelling older adults in Ontario using administrative data. Participants were ≥75 years of age with diagnosed diabetes treated with at least one anti-hyperglycaemic agent between 2014 and 2015. Individuals were categorised as having intensive or conservative glycaemic control (HbA1c <53 mmol/mol [<7%] or 54-69 mmol/mol [7.1-8.5%], respectively), and as undergoing treatment with high-risk (i.e. insulin, sulfonylureas) or low-risk (other) agents. We measured the composite risk of emergency department visits, hospitalisations, or death within 30 days of reaching intensive glycaemic control with high-risk agents. RESULTS: Among 108,620 older adults with diagnosed diabetes in Ontario, the mean (± SD) age was 80.6 (±4.5) years, 49.7% were female, and mean (± SD) diabetes duration was 13.7 (±6.3) years. Overall, 61% of individuals were treated to intensive glycaemic control and 21.6% were treated to intensive control using high-risk agents. Using inverse probability treatment weighting with propensity scores, intensive control with high-risk agents was associated with nearly 50% increased risk of the composite outcome compared with conservative glycaemic control with low-risk agents (RR 1.49, 95% CI 1.08, 2.05). CONCLUSIONS/INTERPRETATION: Our findings underscore the need to re-evaluate glycaemic targets in older adults and to reconsider the use of anti-hyperglycaemic medications that may lead to hypoglycaemia, especially in setting of intensive glycaemic control.