Association between infectious diseases consultation and mortality in hospitalized patients with Gram-negative bloodstream infection: a retrospective population-wide cohort study.

OBJECTIVES: Data supporting routine infectious diseases (ID) consultation in Gram-negative bloodstream infection (GN-BSI) are limited. We evaluated the association between ID consultation and mortality in patients with GN-BSI in a retrospective population-wide cohort study in Ontario using linked health administrative databases. METHODS: Hospitalized adult patients with GN-BSI between April 2017 and December 2021 were included. The primary outcome was time to all-cause mortality censored at 30 days, analyzed using a mixed effects Cox proportional hazards model with hospital as a random effect. ID consultation 1-10 days after the first positive blood culture was treated as a time-varying exposure. RESULTS: Of 30,159 patients with GN-BSI across 53 hospitals, 11,013 (36.5%) received ID consultation. Median prevalence of ID consultation for patients with GN-BSI across hospitals was 35.0% with wide variability (range 2.7-76.1%, interquartile range 19.6-41.1%). 1041 (9.5%) patients who received ID consultation died within 30 days, compared to 1797 (9.4%) patients without ID consultation. In the fully-adjusted multivariable model, ID consultation was associated with mortality benefit (adjusted HR 0.82, 95% CI 0.77-0.88, p < 0.0001; translating to absolute risk reduction of -3.8% or NNT of 27). Exploratory subgroup analyses of the primary outcome showed that ID consultation could have greater benefit in patients with high-risk features (nosocomial infection, polymicrobial or non-Enterobacterales infection, antimicrobial resistance, or non-urinary tract source). CONCLUSIONS: Early ID consultation was associated with reduced mortality in patients with GN-BSI. If resources permit, routine ID consultation for this patient population should be considered to improve patient outcomes.

Epidemiology and clinical relevance of persistent bacteraemia in patients with Gram-negative bloodstream infection: a retrospective cohort study.

OBJECTIVES: The risk factors and outcomes associated with persistent bacteraemia in Gram-negative bloodstream infection (GN-BSI) are not well described. We conducted a follow-on analysis of a retrospective population-wide cohort to characterize persistent bacteraemia in patients with GN-BSI. METHODS: We included all hospitalized patients >18 years old with GN-BSI between April 2017 and December 2021 in Ontario who received follow-up blood culture (FUBC) 2-5 days after the index positive blood culture. Persistent bacteraemia was defined as having a positive FUBC with the same Gram-negative organism as the index blood culture. We identified variables independently associated with persistent bacteraemia in a multivariable logistic regression model. We evaluated whether persistent bacteraemia was associated with increased odds of 30- and 90-day all-cause mortality using multivariable logistic regression models adjusted for potential confounders. RESULTS: In this study, 8807 patients were included; 600 (6.8%) had persistent bacteraemia. Having a permanent catheter, antimicrobial resistance, nosocomial infection, ICU admission, respiratory or skin and soft tissue source of infection, and infection by a non-fermenter or non-Enterobacterales/anaerobic organism were associated with increased odds of having persistent bacteraemia. The 30-day mortality was 17.2% versus 9.6% in those with and without persistent bacteraemia (aOR 1.65, 95% CI 1.29-2.11), while 90-day mortality was 25.5% versus 16.9%, respectively (aOR 1.53, 95% CI 1.24-1.89). Prevalence and odds of developing persistent bacteraemia varied widely depending on causative organism. CONCLUSIONS: Persistent bacteraemia is uncommon in GN-BSI but is associated with poorer outcomes. A validated risk stratification tool may be useful to identify patients with persistent bacteraemia.

Acute health care use among children during the first 2.5 years of the COVID-19 pandemic in Ontario, Canada: a population-based repeated cross-sectional study.

BACKGROUND: The effects of the decline in health care use at the start of the COVID-19 pandemic on the health of children are unclear. We sought to estimate changes in rates of severe and potentially preventable health outcomes among children during the pandemic. METHODS: We conducted a repeated cross-sectional study of children aged 0-17 years using linked population health administrative and disease registry data from January 2017 through August 2022 in Ontario, Canada. We compared observed rates of emergency department visits and hospital admissions during the pandemic to predicted rates based on the 3 years preceding the pandemic. We evaluated outcomes among children and neonates overall, among children with chronic health conditions and among children with specific diseases sensitive to delays in care. RESULTS: All acute care use for children decreased immediately at the onset of the pandemic, reaching its lowest rate in April 2020 for emergency department visits (adjusted relative rate [RR] 0.28, 95% confidence interval [CI] 0.28-0.29) and hospital admissions (adjusted RR 0.43, 95% CI 0.42-0.44). These decreases were sustained until September 2021 and May 2022, respectively. During the pandemic overall, rates of all-cause mortality, admissions for ambulatory care-sensitive conditions, newborn readmissions or emergency department visits or hospital admissions among children with chronic health conditions did not exceed predicted rates. However, after declining significantly between March and May 2020, new presentations of diabetes mellitus increased significantly during most of 2021 (peak adjusted RR 1.49, 95% CI 1.28-1.74 in July 2021) and much of 2022. Among these children, presentations for diabetic ketoacidosis were significantly higher than expected during the pandemic overall (adjusted RR 1.14, 95% CI 1.00-1.30). We observed similar time trends for new presentations of cancer, but we observed no excess presentations of severe cancer overall (adjusted RR 0.91, 95% CI 0.62-1.34). INTERPRETATION: In the first 30 months of the pandemic, disruptions to care were associated with important delays in new diagnoses of diabetes but not with other acute presentations of select preventable conditions or with mortality. Mitigation strategies in future pandemics or other health system disruptions should include education campaigns around important symptoms in children that require medical attention.

Maternal Health Outcomes After Pregnancy-Associated Stroke: A Population-Based Study With 19 Years of Follow-Up.

BACKGROUND: Pregnancy-associated stroke carries high short-term morbidity and mortality, but data on subsequent maternal outcomes are limited. We evaluated long-term maternal health outcomes after pregnancy-associated stroke. METHODS: In this retrospective cohort study, we used administrative data to identify pregnant adults aged ≤49 years with stroke between 2002-2020 in Ontario, Canada and 2 comparison groups: (1) non-pregnant female patients with stroke and (2) pregnant patients without stroke. Patients who survived the index admission were followed until 2021. After propensity score matching, we used Cox regression with a robust variance estimator to compare pregnant patients with stroke and the 2 comparison groups for the composite outcome of death and all-cause non-pregnancy readmission. Where proportional hazard assumption was not met, we reported time-varying hazard ratios (HR) with 95% CIs by modeling the log-hazard ratio as a function of time using restricted cubic splines. RESULTS: We identified 217 pregnant patients with stroke, 7604 non-pregnant patients with stroke, and 1 496 256 pregnant patients without stroke. Of the 202 pregnant patients with stroke who survived the index stroke admission, 41.6% (6.8 per 100 person-years) subsequently died or were readmitted during follow-up. Median follow-up times were 5 years (pregnancy-associated stroke), 3 years (non-pregnant stroke), and 8 years (pregnant without stroke). Pregnant patients with stroke had a lower hazard of death and all-cause readmission compared with non-pregnant patients with stroke at 1-year follow-up (HR, 0.64 [95% CI, 0.44-0.94]), but this association did not persist during longer-term follow-up. Conversely, pregnant patients with stroke had higher hazard of death and readmission compared with pregnant patients without stroke at 1-year follow-up (HR, 5.70 [95% CI, 3.04-10.66]), and this association persisted for a decade. CONCLUSIONS: Stroke during pregnancy is associated with long-term health consequences. It is essential to transition care postpartum to primary or specialty care to optimize vascular health.

Prevalence and Mortality Associated with Bloodstream Organisms: a Population-Wide Retrospective Cohort Study.

Bloodstream infections (BSIs) represent a substantial mortality risk, yet most studies are limited to select pathogens or populations. The aim of this study was to describe the population-wide prevalence of BSIs and examine the associated mortality risk for the responsible microorganisms. We conducted a population-wide retrospective cohort study of BSIs in Ontario in 2017. Blood culture data was collected from almost all microbiology laboratories in Ontario and linked to data sets of patient characteristics. For each organism, we determined the prevalence and crude mortality risk, and using logistic regression models, the adjusted odds of 30-day mortality was calculated relative to patients with negative blood cultures and matched patients without blood culture testing. From 531,065 blood cultures, we identified 22,935 positive BSI episodes in 19,326 patients, for an incidence of 150 per 100,000 population. The most frequently isolated organisms were Escherichia coli, Staphylococcus aureus, coagulase-negative staphylococci, Klebsiella species, and Enterococcus species with 40.2, 22.4, 12.1, 11.1, and 7.1 episodes per 100,000 population respectively. BSI episodes were associated with 17.0% mortality at 30 days. Compared to patients with negative cultures, the adjusted 30-day mortality risk for positive BSIs was 1.47 (95% confidence interval (CI), 1.41 to 1.54) and compared to matched patients without blood culture testing was 2.62 (95% CI, 2.52 to 2.73). Clostridium species were associated with the highest adjusted odds of mortality compared to that of negative cultures (adjusted odds ratio, 5.81; 95% CI, 4.00 to 8.44). Among high incidence pathogens, Staphylococcus aureus had the highest odds ratio of mortality (adjusted odds ratio, 2.14; 95% CI, 1.94 to 2.36). BSIs are associated with increased mortality risk, varying across organisms.

Antibiotic Prescribing Choices and Their Comparative C. Difficile Infection Risks: A Longitudinal Case-Cohort Study.

BACKGROUND: Antibiotic use is the strongest modifiable risk factor for the development of Clostridioides difficile infection, but prescribers lack quantitative information on comparative risks of specific antibiotic courses. Our objective was to estimate risks of C. difficile infection associated with receipt of specific antibiotic courses. METHODS: We conducted a longitudinal case-cohort analysis representing over 90% of Ontario nursing home residents, between 2012 and 2017. Our primary exposure was days of antibiotic receipt in the prior 90 days. Adjustment covariates included: age, sex, prior emergency department or acute care stay, Charlson comorbidity index, prior C. difficile infection, acid suppressant use, device use, and functional status. We examined incident C. difficile infection, including cases identified within the nursing home, and those identified during subsequent hospital admissions. Adjusted and unadjusted regression models were used to measure risk associated with 5- to 14-day courses of 18 different antibiotics. RESULTS: We identified 1708 cases of C. difficile infection (1.27 per 100 000 resident-days). Longer antibiotic duration was associated with increased risk: 10- and 14-day courses incurred 12% (adjusted relative risk [ARR] = 1.12, 95% confidence interval [CI]: 1.09, 1.14) and 27% (ARR = 1.27, 95% CI: 1.21,1.30) more risk compared to 7-day courses. Among 7-day courses with similar indications: moxifloxacin resulted in 121% more risk than amoxicillin (ARR = 2.21, 95% CI: 1.67, 3.08), ciprofloxacin engendered 89% more risk than nitrofurantoin (ARR = 1.89, 95% CI: 1.45, 2.68), and clindamycin resulted in 112% (ARR = 2.12, 95% CI: 1.32, 3.78) more risk than cloxacillin. CONCLUSIONS: C. difficile infection risk increases with antibiotic duration, and there are wide disparities in risks associated with antibiotic courses used for similar indications.

The Benefits and Harms of Antibiotic Prophylaxis for Urinary Tract Infection in Older Adults.

BACKGROUND: The role of antibiotics in preventing urinary tract infection (UTI) in older adults is unknown. We sought to quantify the benefits and risks of antibiotic prophylaxis among older adults. METHODS: We conducted a matched cohort study comparing older adults (≥66 years) receiving antibiotic prophylaxis, defined as antibiotic treatment for ≥30 days starting within 30 days of a positive culture, with patients with positive urine cultures who received antibiotic treatment but did not receive prophylaxis. We matched each prophylaxis recipient to 10 nonrecipients based on organism, number of positive cultures, and propensity score. Outcomes included (1) emergency department (ED) visit or hospitalization for UTI, sepsis, or bloodstream infection within 1 year; (2) acquisition of antibiotic resistance in urinary tract pathogens; and (3) antibiotic-related complications. RESULTS: Overall, 4.7% (151/3190) of UTI prophylaxis patients and 3.6% (n = 1092/30 542) of controls required an ED visit or hospitalization for UTI, sepsis, or bloodstream infection (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.12-1.57). Acquisition of antibiotic resistance to any urinary antibiotic (HR, 1.31; 95% CI, 1.18-1.44) and to the specific prophylaxis agent (HR, 2.01; 95% CI, 1.80-2.24) was higher in patients receiving prophylaxis. While the overall risk of antibiotic-related complications was similar between groups (HR, 1.08; 95% CI, .94-1.22), the risk of Clostridioidesdifficile and general medication adverse events was higher in prophylaxis recipients (HR [95% CI], 1.56 [1.05-2.23] and 1.62 [1.11-2.29], respectively). CONCLUSIONS: Among older adults with UTI, the harms of long-term antibiotic prophylaxis may outweigh their benefits.

Medical Immunosuppression and Outcomes in Cutaneous Melanoma: A Population-Based Cohort Study.

BACKGROUND: Melanoma and the immune system are intimately related. However, the association of immunosuppressive medications (ISMs) with survival in melanoma is not well understood. The study evaluated this at a population level. METHODS: A cohort of patients with a diagnosis of invasive cutaneous melanoma (2007-2015) was identified from the Ontario Cancer Registry and linked to identify demographics, stage at diagnosis, prescription of immunosuppressive medications (both before and after diagnosis), and outcomes. The demographics of patients with and without prescriptions for ISM were compared. Patients eligible for Ontario's Drug Benefit Plan were included to ensure accurate prescription data. The primary outcome was overall survival. Cox Proportional Hazards Regression models identified factors associated with mortality, including use of ISM as a time-varying covariate. RESULTS: Of the 4954 patients with a diagnosis of cutaneous melanoma, 1601 had a prescription for ISM. The median age of the patients was 74 years. Overall, 58.4% of the patients were men (60.5% of those without ISM and 54% of those using ISM; p < 0.001). The use of oral immunosuppression was associated with an increased hazard of death (hazard ratio, 5.84; 95% confidence interval, 5.11-6.67; p < 0.0001) when control was used for age, disease stage at diagnosis, anatomic site, comorbidity, and treatment. Other factors associated with death were increasing age, male sex, increased disease stage, truncal location of primary melanoma, and inadequate treatment. In sensitivity analysis with steroid-only ISM use excluded, survival did not differ significantly (p = 0.355). CONCLUSIONS: The use of immunosuppressive steroids for melanoma is associated with worse overall survival. Use of steroids should be limited when possible.

Maternal cardiovascular disease after twin pregnancies complicated by hypertensive disorders of pregnancy: a population-based cohort study.

BACKGROUND: People whose singleton pregnancy is affected by hypertensive disorders of pregnancy (HDP) are at risk of future cardiovascular disease. It is unclear, however, whether this association can be extrapolated to twin pregnancies. We aimed to compare the association between HDP and future cardiovascular disease after twin and singleton pregnancies. METHODS: We conducted a population-based retrospective cohort study that included nulliparous people in Ontario, Canada, 1992-2017. We compared the future risk of cardiovascular disease among pregnant people from the following 4 groups: those who delivered a singleton without HDP (referent) and with HDP, and those who delivered twins either with or without HDP. RESULTS: The populations of the 4 groups were as follows: 1 431 651 pregnant people in the singleton birth without HDP group; 98 631 singleton birth with HDP; 21 046 twin birth without HDP; and 4283 twin birth with HDP. The median duration of follow-up was 13 (interquartile range 7-20) years. The incidence rate of cardiovascular disease was lowest among those with a singleton or twin birth without HDP (0.72 and 0.74 per 1000 person-years, respectively). Compared with people with a singleton birth without HDP, the risk of cardiovascular disease was highest among those with a singleton birth and HDP (1.47 per 1000 person-years; adjusted hazard ratio [HR] 1.81 [95% confidence interval (CI) 1.72-1.90]), followed by people with a twin pregnancy and HDP (1.07 per 1000 person-years; adjusted HR 1.36 [95% CI 1.04-1.77]). The risk of the primary outcome after a twin pregnancy with HDP was lower than that after a singleton pregnancy with HDP (adjusted HR 0.74 [95% CI 0.57-0.97]), when compared directly. INTERPRETATION: In a twin pregnancy, HDP are weaker risk factors for postpartum cardiovascular disease than in a singleton pregnancy.

The Urine-culturing Cascade: Variation in Nursing Home Urine Culturing and Association With Antibiotic Use and Clostridiodes difficile Infection.

BACKGROUND: Rates of antibiotic use vary widely across nursing homes and cannot be explained by resident characteristics. Antibiotic prescribing for a presumed urinary tract infection is often preceded by inappropriate urine culturing. We examined nursing home urine-culturing practices and their association with antibiotic use. METHODS: We conducted a longitudinal, multilevel, retrospective cohort study based on quarterly nursing home assessments between April 2014 and January 2017 in 591 nursing homes and covering >90% of nursing home residents in Ontario, Canada. Nursing home urine culturing was measured as the proportion of residents with a urine culture in the prior 14 days. Outcomes included receipt of any systemic antibiotic and any urinary antibiotic (eg, nitrofurantoin, trimethoprim/sulfonamides, ciprofloxacin) in the 30 days after the assessment and Clostridiodes difficile infection in the 90 days after the assessment. Adjusted Poisson regression models accounted for 14 resident covariates. RESULTS: A total of 131 218 residents in 591 nursing homes were included; 7.9% of resident assessments had a urine culture in the prior 14 days; this proportion was highly variable across the 591 nursing homes (10th percentile = 3.4%, 90th percentile = 14.3%). Before and after adjusting for 14 resident characteristics, nursing home urine culturing predicted total antibiotic use (adjusted risk ratio [RR] per doubling of urine culturing, 1.21; 95% confidence interval [CI], 1.18-1.23), urinary antibiotic use (RR, 1.33; 95% CI, 1.28-1.38), and C. difficile infection (incidence rate ratio, 1.18; 95% CI, 1.07-1.31). CONCLUSIONS: Nursing homes have highly divergent urine culturing rates; this variability is associated with higher antibiotic use and rates of C. difficile infection.

Implementation of a Physician Incentive Program for 18-Month Developmental Screening in Ontario, Canada.

OBJECTIVES: To evaluate factors associated with uptake of a financial incentive for developmental screening at an enhanced 18-month well-child visit (EWCV) in Ontario, Canada. STUDY DESIGN: Population-based cohort study using linked administrative data of children (17-24 months of age) eligible for EWCV between 2009 and 2017. Logistic regression modeled associations of EWCV receipt by provider and patient characteristics. RESULTS: Of 910 976 eligible children, 54.2% received EWCV (annually, 39.2%-61.2%). The odds of assessment were lower for socially vulnerable children, namely, those from the lowest vs highest neighborhood income quintile (aOR, 0.84; 95% CI, 0.83-0.85), those born to refugee vs nonimmigrant mothers (aOR, 0.90; 95% CI, 0.88-0.93), and to teenaged mothers (aOR, 0.70; 95% CI, 0.69-0.71)). Children were more likely to have had developmental screening if cared for by a pediatrician vs family physician (aOR, 1.28; 95% CI, 1.13-1.44), recently trained physician (aOR, 1.38; 95% CI, 1.29-1.48 for ≤5 years in practice vs ≥21 years) and less likely if the physician was male (aOR, 0.64; 95% CI, 0.61-0.66). For physicians eligible for a pay-for-performance immunization bonus, there was a positive association with screening. CONCLUSIONS: In the context of a universal healthcare system and a specific financial incentive, uptake of the developmental assessment increased over time but remains moderate. The implementation of similar interventions or incentives needs to account for physician factors and focus on socially vulnerable children to be effective.

Primary care of mothers and infants by the same or different physicians: a population-based cohort study.

BACKGROUND: Different primary care delivery models exist for mothers and their infants. We examined whether primary care system performance measures differed when mother-infant dyads received primary care from the same or different providers. METHODS: We conducted a population-based cohort study using Ontario health administrative data from 2004 to 2016. We included primiparous women and their singleton term infants and classified the primary care practitioners who provided the majority of care to the infant and the mother as concordant (same family physician for both; reference group), discordant (a different family physician for each) or pediatrician (pediatrician for the child, family physician for the mother). The primary outcome was nonobstetric maternal hospital admissions between 42 days and 2 years after delivery. RESULTS: Among 481 721 mother-child pairs, 239 033 (49.6%) received concordant care, 114 006 (23.7%) received discordant care, and 128 682 (26.7%) received pediatrician care. Mothers in the pediatrician group were older and had greater comorbidity. Relative to concordant care, maternal nonobstetric hospital admissions occurred similarly under discordant care (adjusted odds ratio [OR] 1.00, 95% confidence interval [CI] 0.96-1.04) and in the pediatrician group (adjusted OR 0.99, 95% CI 0.95-1.02). Maternal deaths were similar under discordant care (adjusted OR 1.00, 95% CI 0.62-1.63) but lower in the pediatrician group (adjusted OR 0.55, 95% CI 0.34-0.89). Maternal primary care visits were lower in both the discordant group (adjusted relative risk [RR] 0.68, 95% CI 0.68-0.69) and the pediatrician group (adjusted RR 0.75, 95% CI 0.75-0.76). Healthy children were more likely to miss the enhanced 18-month well-baby visit under discordant care (adjusted OR 1.06, 95% CI 1.03-1.09) but less likely to miss this visit under pediatrician care (adjusted OR 0.47, 95% CI 0.46-0.49). INTERPRETATION: Concordant care provided to a new mother and her infant by the same family physician was not associated with better primary care health system performance. The reason that pediatric primary care is associated with better maternal and child outcomes remains to be determined.

Sex Differences in Care Need and Survival in Patients Admitted to Nursing Home Poststroke.

BACKGROUND: Women are more likely to be admitted to nursing home after stroke than men. Differences in patient characteristics and outcomes by sex after institutionalization are less understood. We examined sex differences in the characteristics and care needs of patients admitted to nursing home following stroke and their subsequent survival. METHODS: We identified patients with stroke newly admitted to nursing home between April 2011 and March 2016 in Ontario, Canada, with follow-up until March 2018 using linked administrative data. We calculated prevalence ratios and 95% confidence intervals (CIs) for the primary outcomes of dependence for activities of daily living, cognitive impairment, frailty, health instability, and symptoms of depression or pain, comparing women to men. The secondary outcome was all-cause mortality. RESULTS: Among 4831 patients, 60.9% were women. Compared to men, women were older (median age [interquartile range, IQR]: 84 [78, 89] vs. 80 [71, 86]), more likely to be frail (prevalence ratio 1.14, 95% CI [1.08, 1.19]), have unstable health (1.45 [1.28, 1.66]), and experience symptoms of depression (1.25 [1.11, 1.40]) or pain (1.21 [1.13, 1.30]), and less likely to have aggressive behaviors (0.87 [0.80, 0.94]). Overall median survival was 2.9 years. In a propensity-score-matched cohort, women had lower mortality than men (hazard ratio 0.85, 95% CI [0.77, 0.94]), but in the age-stratified survival analysis, the survival advantage in women was limited to those aged 75 years and older. CONCLUSIONS: Despite lower subsequent mortality, women admitted to nursing home after stroke required more care than men. Pain and depression are two treatable symptoms that disproportionately affect women.

Increased Rate of Long-term Mortality Among Burn Survivors: A Population-based Matched Cohort Study.

OBJECTIVE: To estimate long-term mortality following major burn injury compared with matched controls. SUMMARY BACKGROUND DATA: The effect of sustaining a major burn injury on long-term life expectancy is poorly understood. METHODS: Using health administrative data, all adults who survived to discharge after major burn injury between 2003 and 2013 were matched to between 1 and 5 uninjured controls on age, sex, and the extent of both physical and psychological comorbidity. To account for socioeconomic factors such as residential instability and material deprivation, we also matched on marginalization index. The primary outcome was 5-year all-cause mortality, and all patients were followed until death or March 31, 2014. Cumulative mortality estimates were estimated using the Kaplan-Meier method. Cox proportional hazards modeling was used to estimate the association of burn injury with mortality. RESULTS: In total, 1965 burn survivors of mean age 44 (standard deviation 17) years with median total body surface area burn of 15% [interquartile range (IQR) 5-15] were matched to 8671 controls and followed for a median 5 (IQR 2.5-8) years. Five-year mortality was significantly greater among burn survivors (11 vs 4%, P < 0.001). The hazard ratio was greatest during the first year (4.15, 95% CI 3.17-5.42), and declined each year thereafter, reaching 1.65 (95% CI 1.02-2.67) in the fifth year after discharge. Burn survivors had increased mortality related to trauma (mortality rate ratio, MRR 9.8, 95% CI 5-19) and mental illness (MRR 9.1, 95% CI 4-23). CONCLUSIONS: Burn survivors have a significantly higher rate of long-term mortality than matched controls, particularly related to trauma and mental illness. Burn follow-up should be focused on injury prevention, mental healthcare, and detection and treatment of new disease.

Association between Physician Intensity of Antibiotic Prescribing and the Prescription of Benzodiazepines, Opioids and Proton-Pump Inhibitors to Nursing Home Residents: a Population-Based Observational Study.

BACKGROUND: Prescribing patterns for episodic medications, such as antibiotics, might make useful surrogate measures of a physician's overall prescribing practice because use is common, and variation exists across prescribers. However, the extent to which a physician's current antibiotic prescribing practices are associated with the rate of prescription of other potentially harmful medications remains unknown. OBJECTIVE: To examine the association between a physician's rate of antibiotic prescribing and their prescribing rate of benzodiazepines, opioids and proton-pump inhibitors in older adults. DESIGN: Population-based cohort study in nursing homes in Ontario, Canada, which provides comprehensive clinical, behavioural and functional information on all patients. PARTICIPANTS: 1926 physicians who provided care among 128,979 physician-patient pairs in 2015. MAIN MEASURES: Likelihood of prescribing a benzodiazepine, opioid or proton-pump inhibitor between low-, average- and high-intensity antibiotic prescribers, adjusted for patient characteristics. KEY RESULTS: Compared with average-intensity antibiotic prescribers, high-intensity prescribers had an increased likelihood of prescribing a benzodiazepine (odds ratio 1.21 [95% CI, 1.11-1.32]), an opioid (odds ratio 1.28 [95% CI, 1.17-1.39]) or a proton-pump inhibitor (odds ratio 1.38 [95% CI, 1.27-1.51]]. High-intensity antibiotic prescribers were more likely to be high prescribers of all three medications (odds ratio 6.24 [95% CI, 2.90-13.39]) and also more likely to initiate all three medications, compared with average-intensity prescribers. CONCLUSIONS: The intensity of a physician's episodic antibiotic prescribing was significantly associated with the likelihood of new and continued prescribing of opioids, benzodiazepines and proton-pump inhibitors in nursing homes. Patterns of episodic prescribing may be a useful mechanism to target physician-level interventions to optimize general prescribing behaviors, instead of prescribing behaviors for single medications.

Rates over time and regional variation of radical minimally invasive surgery for cervical cancer: A population based study.

OBJECTIVE: Determine rates of radical minimally invasive surgery (MIS) for cervix cancer in Ontario, and whether these rates varied over time and by region. Assess whether changes in the use of MIS impacted length of hospital stay and readmissions. METHODS: Retrospective population-based cohort study of women undergoing radical surgery for cervical cancer between 2002 and 2015. Radical MIS versus laparotomy were compared. Trends in rate of MIS over time, length of hospital stay, and readmission within 30 days were determined. Multivariate logistic regression was used to determine factors associated with MIS approach. RESULTS: 805 women underwent radical abdominal surgery versus 538 radical minimally invasive surgery. Radical MIS increased over the study period, from 17.7% in 2002 to 61.5% in 2015. The most significant predictor of MIS approach was hospital site, with a 14-fold difference in sites with highest and lowest uptake of MIS. Mean length of hospital stay was significantly shorter after radical MIS compared to radical abdominal surgery (1.1 v. 4.2 days). Hospital readmission within 30 days was reduced over the study period for MIS but remained stable following abdominal surgery. CONCLUSIONS: Although rates of radical MIS increased in Ontario over the time period studied, this seems to have been driven by a few high volume centres. Cervical cancer is rare and it takes time to develop the skills to carry out the procedure effectively. Abandonment of minimally invasive radical hysterectomy may have a significant impact on surgical training and subsequent proficiency in the skills unique to this procedure.

Antipsychotic Drug Dispensing in Older Adults With Parkinsonism.

BACKGROUND: Antipsychotic drugs are commonly used to treat psychosis in patients with Parkinson disease; however, individuals with parkinsonism are at risk for serious adverse effects with antipsychotic use. The choice of antipsychotic is critical. OBJECTIVE: To examine the frequency and pattern of antipsychotic prescribing to patients with Parkinson disease and parkinsonism over time. METHODS: Individuals with parkinsonism aged 66 or older in Ontario were studied in a retrospective cohort study from 2005-2013 and followed for prevalent and/or incident antipsychotic drug dispensing. RESULTS: In 2005, 15% of 22,837 individuals with prevalent parkinsonism were dispensed an antipsychotic drug. By 2013, the proportion was 11% of 34,262 individuals. Primary care physicians represented the vast majority of prescribers. Of individuals receiving antipsychotics in 2013, 20% were dispensed a typical antipsychotic drug. Among individuals with incident parkinsonism, living in a nursing home, older age, male sex, a greater number of comorbidities, and a prior diagnosis of dementia were significantly associated with an increased rate of receiving an antipsychotic during follow-up. Among those who received an antipsychotic, factors associated with typical antipsychotic exposure were absence of a prior diagnosis of dementia, higher Charlson comorbidity index, more concurrent medications, more recent year of first parkinsonism diagnosis and not having seen a neurologist, psychiatrist, or geriatrician. CONCLUSION: A substantial proportion of individuals with parkinsonism are exposed to antipsychotic drugs, including typical antipsychotics. Given the risks of these drugs to individuals with parkinsonism, education of prescribers, particularly primary care physicians, is needed.

Relevance of frailty to mortality associated with the use of antipsychotics among community-residing older adults with impaired cognition.

PURPOSE: To examine the association between new antipsychotic use and mortality over 6 months among community-based older adults with cognitive impairment, and variation in risk by frailty and sex. METHODS: We conducted a retrospective cohort study of older (aged 66+) home care clients in Ontario, Canada, using linked administrative health and clinical databases. Included were clients with dementia and/or significant cognitive impairment assessed during April 2008 to March 2013. Frailty was defined using a validated 72-item index. Exposed were those newly dispensed an antipsychotic in the 6 months post cohort entry, with no such claims in the year prior to drug index date. Two-stage matching defined unexposed clients and their index date (matching on age, sex, frailty, assessment year, and propensity score). Outcome was time to death following index date. Cause-specific hazards models were used, and number needed to harm at 6 months was estimated from cumulative incidence function curves. RESULTS: Among 4955 matched exposed-unexposed pairs, new antipsychotic users showed a significantly increased hazard of mortality at 1, 3, and 6 months relative to unexposed, with the highest risk observed in the first month (hazard ratio [HR] = 2.08 [95% CI, 1.79-2.43]). At 1 month, risk was significantly higher for robust (HR = 3.72 [95% CI, 2.45-5.66]) vs frail (HR = 1.74 [95% CI, 1.40-2.17], P = .002) clients. The number needed to harm was 22.7 and did not vary by frailty but was lower for men (14.9) than for women (35.0). CONCLUSIONS: Risk of antipsychotic-associated mortality was highest in the first month following exposure, varied significantly by client frailty, and was greater among men than among women.

Variation in the health outcomes associated with frailty among home care clients: relevance of caregiver distress and client sex.

BACKGROUND: The identification of contextual factors that modify associations between client frailty and their health and service use outcomes is essential for informed home health care and policy planning. Our objective was to examine variation in the associations between frailty and select 1-year health outcomes by caregiver distress and client sex among community-residing older care recipients. METHODS: We conducted a retrospective cohort study using linked population-based clinical and health administrative databases for all long-stay home care clients (n = 234,552) aged 66+ years assessed during April 2010-2013 in Ontario, Canada. Frailty was assessed using a previously validated 72-item frailty index (FI). Presence of caregiver distress was derived from clinical assessment items administered by trained home care assessors. Multivariable log-binomial regression models were used to examine variations in the associations between frailty and outcomes of interest (mortality, nursing home [NH] placement, all-cause and prolonged hospitalization) by caregiver distress, with further model stratification by client sex. RESULTS: Frailty prevalence varied little by sex (19.3% women, 19.9% men) despite significant sex-differences in clients' sociodemographic and health characteristics. In both sexes, frailty was significantly associated with all outcomes, particularly NH placement (RR = 3.84, 95%CI 3.75-3.93) and death (RR = 2.32, 95%CI 2.27-2.37), though risk ratios were greater for women. Caregiver distress was more common with increasing frailty and for male clients, and a significant independent predictor of NH placement and prolonged hospitalization in both sexes. The association between frailty and NH placement (but not other outcomes) varied by caregiver distress for both men and women (p < 0.001 interaction terms), showing a greater magnitude of association among clients without (vs. with) a distressed caregiver. CONCLUSIONS: As caregiver distress varies by client sex, represents a key driver of NH placement (even among relatively robust clients), and modifies the impact of other risk factors such as frailty, it should be routinely assessed. Further, sex-differences should be considered when developing and evaluating community-based services for older adults and their caregivers.

The prevalence and health consequences of frailty in a population-based older home care cohort: a comparison of different measures.

BACKGROUND: Evaluating different approaches to identifying frail home care clients at heightened risk for adverse health outcomes is an important but understudied area. Our objectives were to determine the prevalence and correlates of frailty (as operationally defined by three measures) in a home care cohort, the agreement between these measures, and their predictive validity for several outcomes assessed over one year. METHODS: We conducted a retrospective cohort study with linked population-based administrative and clinical (Resident Assessment Instrument [RAI]) data for all long-stay home care clients (aged 66+) assessed between April 2010-2013 in Ontario, Canada (n = 234,552). We examined two versions of a frailty index (FI), a full and modified FI, and the CHESS scale, compared their baseline characteristics and their predictive accuracy (by calculating the area under the ROC curve [AUC]) for death, long-term care (LTC) admission, and hospitalization endpoints in models adjusted for age, sex and comorbidity. RESULTS: Frailty prevalence varied by measure (19.5, 24.4 and 44.1 %, for full FI, modified FI and CHESS, respectively) and was similar among female and male clients. All three measures were associated with a significantly increased risk of death, LTC admission and hospitalization endpoints in adjusted analyses but their addition to base models resulted in modest improvement for most AUC estimates. There were significant differences between measures in predictive accuracy, with the full FI demonstrating a higher AUC for LTC admission and CHESS a higher AUC for hospitalization - although none of the measures performed well for the hospitalization endpoints. CONCLUSIONS: The different approaches to detecting vulnerability resulted in different estimates of frailty prevalence among home care clients in Ontario. Although all three measures were significant predictors of the health outcomes examined, the gains in predictive accuracy were often modest with the exception of the full FI in predicting LTC admission. Our findings provide some support for the clinical utility of a comprehensive FI measure and also illustrate that it is feasible to derive such a measure at the population level using routinely collected data. This may facilitate further research on frailty in this setting, including the development and evaluation of interventions for frailty.