Household food insecurity and health service use for mental and substance use disorders among children and adolescents in Ontario, Canada.

BACKGROUND: Food insecurity is a serious public health problem and is linked to the mental health of children and adolescents; however, its relationship with mental health service use is unknown. We sought to estimate the association between household food insecurity and contact with health services for mental or substance use disorders among children and adolescents in Ontario, Canada. METHODS: We used health administrative data, linked to 5 waves of the Canadian Community Health Survey, to identify children and adolescents (aged 1-17 yr) who had a household response to the Household Food Security Survey Module. We identified contacts with outpatient and acute care services for mental or substance use disorders in the year before survey completion using administrative data. We estimated prevalence ratios for the association between household food insecurity and use of mental health services, adjusting for several confounding factors. RESULTS: The sample included 32 321 children and adolescents, of whom 5216 (16.1%) were living in food-insecure households. Of the total sample, 9.0% had an outpatient contact and 0.6% had an acute care contact for a mental or substance use disorder. Children and adolescents in food-insecure households had a 55% higher prevalence of outpatient contacts (95% confidence interval [CI] 41%-70%), and a 74% higher prevalence of acute care contacts (95% CI 24%-145%) for a mental or substance use disorder, although contacts for substance use disorders were uncommon. INTERPRETATION: Children and adolescents living in a food-insecure household have greater use of health services for mental or substance use disorders than those living in households without food insecurity. Focused efforts to support food-insecure families could improve child and adolescent mental health and reduce strain on the mental health system.

Epilepsy Surgery in Adult Stroke Survivors with New-Onset Drug-Resistant Epilepsy.

BACKGROUND: Despite its effectiveness, surgery for drug-resistant epilepsy is underutilized. However, whether epilepsy surgery is also underutilized among patients with stroke-related drug-resistant epilepsy is unclear. Therefore, our objectives were to estimate the rates of epilepsy surgery assessment and receipt among patients with stroke-related drug-resistant epilepsy and to identify factors associated with these outcomes. METHODS: We used linked health administrative databases to conduct a population-based retrospective cohort study of adult Ontario, Canada residents discharged from an Ontario acute care institution following the treatment of a stroke between January 1, 1997, and December 31, 2020, without prior evidence of seizures. We excluded patients who did not subsequently develop drug-resistant epilepsy and those with other epilepsy risk factors. We estimated the rates of epilepsy surgery assessment and receipt by March 31, 2021. We planned to use Fine-Gray subdistribution hazard models to identify covariates independently associated with our outcomes, controlling for the competing risk of death. RESULTS: We identified 265,081 patients who survived until discharge following inpatient stroke treatment, 1,902 (0.7%) of whom subsequently developed drug-resistant epilepsy (805 women; mean age: 67.0 ± 13.1 years). Fewer than six (≤0.3%) of these patients were assessed for or received epilepsy surgery before the end of follow-up (≤55.5 per 100,000 person-years). Given that few outcomes were identified, we could not proceed with the multivariable analyses. CONCLUSIONS: Patients with stroke-related drug-resistant epilepsy are infrequently considered for epilepsy surgery that could reduce morbidity and mortality.

Quality of antibiotic prescribing for pediatric community-acquired Pneumonia in outpatient care.

BACKGROUND: Antibiotics remain the primary treatment for community acquired pneumonia (CAP), however rising rates of antimicrobial resistance may jeopardize their future efficacy. With higher rates of disease reported in the youngest populations, effective treatment courses for pediatric pneumonia are of paramount importance. This study is the first to examine the quality of pediatric antibiotic use by agent, dose and duration. METHODS: A retrospective cohort study included all outpatient/primary care physician visits for pediatric CAP (aged < 19 years) between January 1 2014 to December 31 2018. Relevant practice guidelines were identified, and treatment recommendations extracted. Amoxicillin was the primary first-line agent for pediatric CAP. Categories of prescribing included: guideline adherent, effective but unnecessary (excess dose and/or duration), under treatment (insufficient dose and/or duration), and not recommended. Proportions of attributable-antibiotic use were examined by prescribing category, and then stratified by age and sex. RESULT(S): A total of 42,452 episodes of pediatric CAP were identified. Of those, 31,347 (76%) resulted in an antibiotic prescription. Amoxicillin accounted for 51% of all prescriptions. Overall, 27% of prescribing was fully guideline adherent, 19% effective but unnecessary, 10% under treatment, and 44% not recommended by agent. Excessive duration was the hallmark of effective but unnecessary prescribing (97%) Macrolides accounted for the majority on non-first line agent use, with only 32% of not recommended prescribing preceded by a previous course of antibiotics. CONCLUSION(S): This study is the first in Canada to examine prescribing quality for pediatric CAP by agent, dose and duration. Utilizing first-line agents, and shorter-course treatments are targets for stewardship.

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.

Trends in basal insulin prescribing in older adults with chronic kidney disease in Ontario, Canada: A population-based analysis from 2010 to 2020.

AIM: To examine trends in basal insulin prescribing in older adults with chronic kidney disease (CKD). MATERIALS AND METHODS: We conducted a population-based study of adults aged 66 years or older with treated diabetes from 1 January 2010 to 30 September 2020 in Ontario, Canada. We examined prevalent and incident prescriptions for human NPH, Levemir, glargine-100, Basaglar, glargine-300, and degludec insulin over 43 study intervals. We present trends in those with CKD, and in a subgroup, by estimated glomerular filtration rate (eGFR). To provide context for prescribing, we provide demographics, co-morbidities, and the healthcare utilization of included patients. RESULTS: In CKD, use of basal insulin was about 2-fold higher than in the general treated diabetes cohort. Prescriptions for NPH declined over time, while prescriptions for Levemir and glargine-100 increased until 2018 then decreased. Following drug formulary approval (September 2018), prescriptions for glargine-300 and degludec increased substantially. Incident prescriptions for basal insulin in CKD declined over time; however, in those with an eGFR of less than 30 ml/min/1.73m2 , rates remained stable. In recent years, rates of degludec and glargine-300 have rivalled glargine-100. CONCLUSIONS: In an era of new oral and injectable diabetes medications, the use of basal insulin has declined in older adults with CKD. However, in those with more advanced CKD, basal insulin, particularly newer analogues, remain a mainstay treatment.

Utility, Limitations and Opportunities for Using Linked Health Administrative Data to Study Homelessness in Ontario.

Homelessness is a significant social issue within Canada but is difficult to quantify at the population level. In this paper, we discuss the development and use of a case ascertainment algorithm that identifies people experiencing homelessness through health administrative data. We highlight the appropriateness of various uses of this method given its key strengths and limitations. Finally, we discuss plans to improve this methodology and broaden its use through the addition of linkable administrative data from non-health sectors, such as emergency shelters and social services organizations.

Concussion in adolescence and the risk of multiple sclerosis: A retrospective cohort study.

BACKGROUND: Physical trauma, specifically concussions sustained during adolescence, has been hypothesized to be a risk factor for multiple sclerosis (MS). OBJECTIVE: To examine the association between adolescent concussions and future MS diagnosis. METHODS: This retrospective study using linked administrative databases from Ontario, Canada, identified 97,965 adolescents (age 11-18 years) who sustained ⩾1 concussion and presented to an emergency department between 1992 and 2011. Cases were matched 1:3 with individuals who had not sustained a concussion based on age, sex, address, and index date. The primary outcome was MS diagnosis, using a validated MS diagnosis definition: ⩾1 hospitalization or ⩾5 physician billings within 2 years. RESULTS: A concussion during adolescence was associated with a significantly increased risk of MS (hazard ratio (HR) = 1.29, p = 0.03). Sex-specific analysis revealed that only males who sustained a concussion in adolescence had a raised risk of MS (HR = 1.41, p = 0.04). CONCLUSION: This study supports an association between concussions in adolescence and future MS diagnoses, highlighting the potentially serious long-term effects of concussions.

Survival and Health Care Use After Deep Brain Stimulation for Parkinson's Disease.

OBJECTIVES: To compare long-term survival of Parkinson's disease (PD) patients with deep brain stimulation (DBS) to matched controls, and examine whether DBS was associated with differences in injurious falls, long-term care, and home care. METHODS: Using administrative health data (Ontario, Canada), we examined DBS outcomes within a cohort of individuals diagnosed with PD between 1997 and 2012. Patients receiving DBS were matched with non-DBS controls by age, sex, PD diagnosis date, time with PD, and a propensity score. Survival between groups was compared using the log-rank test and marginal Cox proportional hazards regression. Cumulative incidence function curves and marginal subdistribution hazard models were used to assess effects of DBS on falls, long-term care admission, and home care use, with death as a competing risk. RESULTS: There were 260 DBS recipients matched with 551 controls. Patients undergoing DBS did not experience a significant survival advantage compared to controls (log-rank test p = 0.50; HR: 0.89, 95% CI: 0.65-1.22). Among patients <65 years of age, DBS recipients had a significantly reduced risk of death (HR: 0.49, 95% CI: 0.28-0.84). Patients receiving DBS were more likely than controls to receive care for falls (HR: 1.56, 95% CI: 1.19-2.05) and home care (HR: 1.59, 95% CI: 1.32-1.90), while long-term care admission was similar between groups. CONCLUSIONS: Receiving DBS may increase survival for younger PD patients who undergo DBS. Future studies should examine whether survival benefits may be attributed to effects on PD or the absence of comorbidities that influence mortality.

Incidence, predictors and patterns of care of patients with very severe hypertriglyceridemia in Ontario, Canada: a population-based cohort study.

BACKGROUND: The incidence of severe (S-HTG) and very severe hypertriglyceridemia (VS-HTG) among Canadians is unknown. This study aimed to determine the incidence, characteristics, predictors and care patterns for individuals with VS-HTG. METHODS: Using linked administrative healthcare databases, a population-based cohort study of Ontario adults was conducted to determine incidence of new onset S-HTG (serum triglycerides (TG) > 10-20 mmol/L) and VS-HTG (TG > 20 mmol/L) between 2010 and 2015. Socio-demographic and clinical characteristics of those with VS-HTG were compared to those who had no measured TG value > 3 mmol/L. Univariable and multivariable logistic regression were used to determine predictors for VS-HTG. Healthcare patterns were evaluated for 2 years following first incidence of TG > 20 mmol/L. RESULTS: Incidence of S-HTG and VS-HTG in Ontario was 0.16 and 0.027% among 10,766,770 adults ≥18 years and 0.25 and 0.041% among 7,040,865 adults with at least one measured TG, respectively. Predictors of VS-HTG included younger age [odds ratios (OR) 0.64/decade, 95% confidence intervals (CI) 0.62-0.66], male sex (OR 3.83; 95% CI 3.5-4.1), diabetes (OR 5.38; 95% CI 4.93-5.88), hypertension (OR 1.69; 95% CI 1.54-1.86), chronic liver disease (OR 1.71; 95% CI 1.48-1.97), alcohol abuse (OR 2.47; 95% CI 1.90-3.19), obesity (OR 1.49; 95% CI 1.13-1.98), and chronic kidney disease (OR 1.39; 95% CI 1.19-1.63). CONCLUSION: The 5-year incidence of S-HTG and VS-HTG in Canadian adults was 1 in 400 and 1 in 2500, respectively. Males, those with diabetes, obese individuals and those with alcohol abuse are at highest risk for VS-HTG and may benefit from increased surveillance.

Opioid Prescribing Practices for Women Undergoing Elective Gynecologic Surgery.

STUDY OBJECTIVE: To describe the opioid prescribing practices in opioid-naive women undergoing elective gynecologic surgery for benign indications and identify risk factors associated with increased perioperative opioid use. We also explored factors associated with new persistent opioid use in women with perioperative opioid use. DESIGN: Retrospective, population-based cohort study. SETTING: We used linked administrative data from a government-administered single-payer provincial healthcare system in Canada. This study was undertaken at ICES, a not-for-profit research institute in Ontario, Canada. PATIENTS: We followed opioid-naive adult women who underwent benign elective gynecologic surgery between 2013 and 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was perioperative opioid use defined as ≥1 opioid prescription from 30 days before to 14 days after surgery. New persistent opioid use after gynecologic surgery was defined as having filled 1 or more opioid prescriptions between 91 days and 180 days postoperatively. Multivariable log-linear regression analyses were employed to adjust for clinical and demographic data. Of the 132 506 patients included in our cohort, most (74.3%) underwent minor gynecologic procedures. Perioperative opioid use was documented in 27 763 (21.0%) patients, and there was a significant decreasing trend (p <.001) in the proportion of patients with perioperative opioid use from 21.8% in 2013 to 18.5% in 2018. Factors associated with increased perioperative opioid use included younger age; higher income quintile; urban dwellers; and diagnosis of infertility, endometriosis, or adnexal mass. Perioperative opioid use was an independent risk factor for persistent use (adjusted relative risk 1.40; 95% confidence interval, 1.13-1.72) and for every 65 patients prescribed opioids associated with gynecologic surgery, one developed new persistent opioid use. The highest risk factor for developing persistent use was filling a high-dose opioid prescription (adjusted relative risk5th quintileOME 2.33; 95% confidence interval, 1.83-2.96). CONCLUSION: One in 5 women who undergo a gynecologic procedure has a new exposure to opioids. For every 65 patients who fill an opioid prescription after their gynecologic surgery, one will experience prolonged opioid use.

Were Snowbirds Disproportionally Impacted by COVID-19? An Ontario Analysis.

Early in the first wave of the COVID-19 pandemic, many older adult Canadians who routinely spend the winter months in warmer regions (colloquially known as "snowbirds") returned to Canada. While numerous infections were attributed to travel-related exposure at that time, little is known about the impact of COVID-19 on returning snowbirds. This population-based analysis from Ontario suggests that snowbirds were not disproportionately impacted by the pandemic. However, as older adults, they remain at high risk of complications once infected. These findings underscore the need for continued caution in this older adult population.

Infective Endocarditis Hospitalizations and Antibiotic Prophylaxis Rates Before and After the 2007 American Heart Association Guideline Revision.

BACKGROUND: In 2007, the American Heart Association recommended antibiotic prophylaxis for the prevention of infective endocarditis (IE) for only the highest-risk patients. Whether this change affected the use of antibiotic prophylaxis and the incidence of IE is unclear. METHODS: IE-related hospitalizations were identified from 2002 to 2014 among all adults and those at high and moderate risk for IE, stratified by age. Prescriptions for antibiotic prophylaxis were obtained from the Ontario Drug Benefit database for adults ≥65 years of age. Outcomes were antibiotic prophylaxis prescription rates and incidence of IE-related hospitalization. Trends in patient and pathogen characteristics were analyzed. Time series analyses were performed with segmented regression and change-point analyses. RESULTS: Prescriptions for antibiotic prophylaxis decreased substantially in the moderate-risk cohort after the guideline revision (mean quarterly prescriptions, 30 680 versus 17 954 [level change, -6,481; P=0.0004] per 1 million population) with a minimal, yet significant, decrease followed by a slow increase in the high-risk group. There were 7551 IE-related hospitalizations among 6884 adults ≥18 years of age. Among adults ≥65 years of age, the mean IE rate increased from 872 to 1385 and 229 to 283 per 1 million population at risk per quarter in the high- and moderate-risk groups, respectively. Change-point analyses indicated that this increase occurred in the second half of 2010 in adults ≥65 years of age, 3 years after the American Heart Association guideline revision. Staphylococcus aureus and streptococcal species accounted for 30.3% and 26.4% of all IE, with a decrease in streptococcal infections over time. CONCLUSIONS: Antibiotic prophylaxis decreased significantly in the moderate-risk group with minimal change in the high-risk group after the American Heart Association guideline revision in 2007. However, IE-related hospitalizations increased among both high- and moderate-risk patients 3 years after the revision. Our study provides support for the cessation of antibiotic prophylaxis in the moderate-risk population.

First-Ever Ischemic Stroke and Incident Major Adverse Cardiovascular Events in 93 627 Older Women and Men.

Background and Purpose- Stroke risk is sex-specific, but little is known about sex differences of poststroke major adverse cardiovascular events (MACEs). Stroke-related brain damage causes autonomic dysfunction and inflammation, sometimes resulting in cardiac complications. Sex-specific cardiovascular susceptibility to stroke without the confounding effect of preexisting heart disease constitutes an unexplored field because previous studies focusing on sex differences in poststroke MACE have not excluded patients with known cardiovascular comorbidities. We therefore investigated sex-specific risks of incident MACE in a heart disease-free population-based cohort of patients with first-ever ischemic stroke and propensity-matched individuals without stroke. Methods- We included Ontario residents ≥66 years, without known cardiovascular comorbidities, with first-ever ischemic stroke between 2002 and 2012 and propensity-matched individuals without stroke. We investigated the 1-year risk of incident MACE (acute coronary syndrome, myocardial infarction, incident coronary artery disease, coronary revascularization procedures, incident heart failure, or cardiovascular death) separately for females and males. For estimating cause-specific adjusted hazard ratios, we adjusted Cox models for variables with weighted standardized differences >0.10 or those known to influence MACE risk. Results- We included 93 627 subjects without known cardiovascular comorbidities; 21 931 with first-ever ischemic stroke and 71 696 propensity-matched subjects without stroke. Groups were well-balanced on propensity-matching variables. There were 53 476 women (12 421 with and 41 055 without ischemic stroke) and 40 151 men (9510 with and 30 641 without ischemic stroke). First-ever ischemic stroke was associated with increased risk of incident MACE in both sexes. The risk was time-dependent, highest within 30 days (women: adjusted hazard ratio, 25.1 [95% CI, 19.3-32.6]; men: aHR, 23.4 [95% CI, 17.2-31.9]) and decreasing but remaining significant between 31 and 90 days (women: aHR, 4.8 [95% CI, 3.8-6.0]; men: aHR, 4.2 [95% CI, 3.3-5.4]), and 91 to 365 days (aHR, 2.1 [95% CI, 1.8-2.3]; men: aHR, 2.0 [95% CI, 1.7-2.3]). Conclusions- In this large population-based study, ischemic stroke was independently associated with increased risk of incident MACE in both sexes.

Factors associated with endocrine therapy adherence among post-menopausal women treated for early-stage breast cancer in Ontario, Canada.

PURPOSE: Adherence to adjuvant endocrine therapy among post-menopausal breast cancer patients is an important survivorship care issue. We explored factors associated with endocrine therapy adherence and survival in a large real-world population-based study. METHODS: We used health administrative databases to follow women (aged ≥ 66 years) who were diagnosed with breast cancer and started on adjuvant endocrine therapy from 2005 to 2010. Adherence was measured by medical possession ratio (MPR) and characterized as low (< 39% MPR), intermediate (40-79% MPR), or high (≥ 80% MPR) over a 5-year period. We investigated factors associated with adherence using a multinomial logistic regression model. Factors associated with all-cause mortality (5 years after starting endocrine therapy) were investigated using a multivariable Cox proportional hazards model. RESULTS: We identified 5692 eligible patients starting adjuvant endocrine therapy who had low, intermediate, and high adherence rates of 13% (n = 749), 13% (n = 733), and 74% (n = 4210), respectively. Lower rates of adherence were associated with increased age [low vs. high adherence: odds ratio (OR) 1.03, 95% CI 1.02-1.05 (per year); intermediate vs. high adherence: OR 1.02, 95% CI 1.01-1.04 (per year)]. High adherence was associated with previous use of adjuvant chemotherapy (low versus high adherence OR 0.42, 95% CI 0.30-0.59) and short-term follow-up with a medical oncologist within 4 months of starting endocrine therapy (low versus high adherence OR 0.83, 95% CI 0.69-0.99). Unadjusted analysis showed increased survival among patients with high endocrine therapy adherence. However, an independent association was no longer clearly detected after controlling for confounders. CONCLUSION: Interventions to improve adjuvant endocrine therapy adherence are warranted. Non-adherence may be a more significant issue among elderly patients. Short-term follow-up visit by a patient's medical oncologist after starting endocrine therapy may help to improve compliance.

The association between climate, geography and respiratory syncitial virus hospitalizations among children in Ontario, Canada: a population-based study.

BACKGROUND: Respiratory syncytial virus (RSV) infection is a major cause of hospitalization in young children in Canada, despite routine immunoprophylaxis in those with medical risk factors. We aimed to determine if cold temperatures are associated with RSV hospitalization. METHODS: We conducted a population-based nested case-control study of children in Ontario, Canada, using health administrative data. We compared children hospitalized for RSV between September 1, 2011 and August 31, 2012 to age and sex matched controls. We used multivariable logistic regression to identify associations between minimum daily temperature and RSV hospitalizations with adjustment for sociodemographic and environmental factors. RESULTS: We identified 1670 children with RSV hospitalizations during the study period and 6680 matched controls. Warmer temperatures (OR = 0.94, 95%CI: 0.93, 0.95) were associated with lower odds of RSV hospitalization. Southern ecozone (OR = 1.6, 95%CI: 1.2, 2.1), increased ozone concentration (OR = 1.03, 95%CI: 1.01, 1.06) and living in a lower income neighbourhood (OR = 1.3, 95%CI: 1.1, 1.5) significantly increased the odds of RSV hospitalization, as did living in a household with a larger number of siblings in a sub-cohort of children (OR = 1.34, 95%CI: 1.26, 1.41). CONCLUSIONS: In Ontario, the likelihood of having an RSV hospitalization is associated with colder temperature exposures and socioeconomic factors.

Disparities in Deep Brain Stimulation Use for Parkinson's Disease in Ontario, Canada.

OBJECTIVE: To examine whether sociodemographic characteristics and health care utilization are associated with receiving deep brain stimulation (DBS) surgery for Parkinson's disease (PD) in Ontario, Canada. METHODS: Using health administrative data, we identified a cohort of individuals aged 40 years or older diagnosed with incident PD between 1995 and 2009. A case-control study was used to examine whether select factors were associated with DBS for PD. Patients were classified as cases if they underwent DBS surgery at any point 1-year after cohort entry until December 31, 2016. Conditional logistic regression modeling was used to estimate the adjusted odds of DBS surgery for sociodemographic and health care utilization indicators. RESULTS: A total of 46,237 individuals with PD were identified, with 543 (1.2%) receiving DBS surgery. Individuals residing in northern Ontario were more likely than southern patients to receive DBS surgery [adjusted odds ratio (AOR) = 2.23, 95% confidence interval (CI) = 1.15-4.34]; however, regional variations were not observed after accounting for medication use among older adults (AOR = 1.04, 95% CI = 0.26-4.21). Patients living in neighborhoods with the highest concentration of visible minorities were less likely to receive DBS surgery compared to patients living in predominantly white neighborhoods (AOR = 0.27, 95% CI = 0.16-0.46). Regular neurologist care and use of multiple PD medications were positively associated with DBS surgery. CONCLUSIONS: Variations in use of DBS may reflect differences in access to care, specialist referral pathways, health-seeking behavior, or need for DBS. Future studies are needed to understand drivers of potential disparities in DBS use.

Risks of preoperative anemia in women undergoing elective hysterectomy and myomectomy.

BACKGROUND: Hysterectomy is one of the most common surgeries performed worldwide. Identification of modifiable risk factors for complications or readmissions could lead to targeted interventions to improve patient care and reduce health care costs. Preoperative anemia has been identified as a risk factor for adverse postoperative outcomes following noncardiac surgery. However, studies have not focused on young and healthy surgical populations, such as women undergoing gynecologic surgery for benign indications. OBJECTIVE: The purpose of this study was to evaluate whether preoperative anemia in women undergoing elective hysterectomy or myomectomy for benign indications was associated with increased 30 day postoperative morbidity and mortality. STUDY DESIGN: In this retrospective, population-based cohort study, we followed up adult women (≥18 years of age) who underwent elective hysterectomy or myomectomy (laparoscopic/laparotomy) between the years 2013 and 2015 for benign indications in Ontario, Canada. We used linked administrative data from a government-administered, single-payer provincial health care system using Canadian Classification of Health Interventions intervention codes, International Classification of Diseases, 10th revision, diagnostic codes, physician billing codes, and laboratory data from both community and hospital laboratories across the province. Our exposure of interest was preoperative anemia, defined as a hemoglobin value <12 g/dL on the complete blood count measured closest to the date of surgery. Our primary outcome was the composite of 30 day postoperative morbidity and mortality. Secondary outcomes were 5 individual components of the primary outcome: death, transfusion, surgical site infection, venothromboembolism, and return to the hospital within 30 days. To adjust for confounding, we generated a propensity score using a multiple logistic regression model in which the presence of anemia was regressed on all baseline characteristics. We matched anemic to nonanemic patients on the logit of the propensity score. Using an unadjusted log-binomial model estimated using generalized estimating equations to account for the matched pairs, we calculated the relative risk, 95% confidence intervals, and P values to evaluate the effect of anemia on outcomes. RESULTS: Of the 16,218 women in the cohort, 3664 (22.6%) had anemia. After propensity matching, standardized differences in all baseline characteristics (n = 3261 per group) were <0.10. In the matched cohort, the primary outcome (death, complications, or readmission) occurred in 41.2% of anemic patients and 36.2% of nonanemic patients (relative risk, 1.14, 95% confidence interval, 1.07-1.21, P < .0001; absolute risk reduction, 5.03%, 95% confidence interval, 2.70-7.36; (number needed to harm = 20). The risk of transfusion was significantly higher in anemic patients (relative risk, 3.25, 95% confidence interval, 2.67-3.95, P < .0001; absolute risk reduction, 8.34%, 95% confidence interval, 7.06-9.63; number needed to harm = 12). There was no difference in other secondary outcomes. In a subgroup analysis (women >55 years vs ≤55, n = 736), older women were at increased risk of the primary outcome (relative risk, 1.40, 95% confidence interval, 1.12-1.76, P = .004), transfusion (relative risk, 4.20, 95% confidence interval, 1.65-10.72, P = .003), surgical site infection (relative risk, 1.35, 95% confidence interval, 1.01-1.81, P = .04), and return to the hospital (relative risk, 2.36, 95% confidence interval, 1.54-3.62, P < .0001). CONCLUSION: Preoperative anemia in women undergoing elective hysterectomy/myomectomy was common and is an independent risk factor for 30 day postoperative adverse outcomes, especially in older women.

The influence of prenatal mental health service use on the incidence of childhood asthma: a population-based cohort study.

OBJECTIVES: We aimed to determine whether maternal mental health service use during pregnancy, a potential proxy measure of prenatal maternal stress, is associated with the development of asthma in a large population-based sample of children. We hypothesized that children born to mothers with mental health service use during pregnancy would have a higher incidence of childhood asthma. STUDY DESIGN: Health administrative data from Ontario, Canada (population >13 million) was used to identify pairs of mothers linked with their children born between April 1, 2001 to March 31, 2002. Descriptive statistics were used to compare the cumulative incidence of asthma by age 12 years in children whose mothers did or did not have prenatal mental health service use. Multivariable logistic regression was used to estimate the association between prenatal maternal mental health service use and childhood asthma incidence, after adjusting for the child's sex, residency (rural vs. urban), socioeconomic status, comorbid health conditions, low birthweight, and maternal history of asthma. RESULTS: In a population-based sample of 122,333 children, those born to mothers with mental health service use during pregnancy had increased odds of developing asthma (odds ratio: 1.16, 95% confidence intervals: 1.12, 1.20, p < 0.001). CONCLUSIONS: Prenatal maternal mental health service use is an independent risk factor for the development of asthma in childhood. This supports growing evidence for the importance of in utero exposure to maternal stress factors in asthma pathogenesis. This study highlights a potential strategy for the primary prevention of childhood asthma, namely improved recognition and management of mental health issues and stress in pregnant mothers.

Post-mastectomy radiation in node-positive breast cancer in Ontario.

More recent guidelines are more supportive for post-mastectomy radiation in all node-positive breast cancer patients. We examined the rate and predictors of post-mastectomy radiation receipt in Ontario Canada from 2010 to 2014. Of 6535 node-positive post-mastectomy patients, 73.9% received radiation. The rate was 68.7% (2903/4227) among women with 1-3 positive nodes. Radiation was less likely to be administered to women who were older, had high levels of comorbidity, or presented with early stages of breast cancer. Regional practice variation was reassuringly modest.

Association between known or strongly suspected malignant hyperthermia susceptibility and postoperative outcomes: an observational population-based study.

PURPOSE: Whether current standards of care management for malignant hyperthermia (MH)-susceptible patients result in acceptable postoperative clinical outcomes at a population level is not known. Our objective was to determine if patients with susceptibility to MH experienced similar outcomes as patients without MH susceptibility after surgery under general anesthesia. METHODS: This was a retrospective, population-based cohort study from 1 April 2009 until 31 March 2016 in the Canadian province of Ontario. Participants were adults who underwent common in- or outpatient surgeries under general anesthesia. The exposure studied was either known or strongly suspected MH susceptibility as determined by usage of a specific physician billing code. The primary outcome was a composite of all-cause death, hospital readmission, or major postoperative complications, all within 30 postoperative days. Separate analyses were employed, based on whether a patient had in- or outpatient surgery. Inverse probability of exposure weighting based on the propensity score was used to estimate adjusted exposure effects. RESULTS: The cohort included 957,876 patients (583,254 in- and 374,622 outpatients). There were 2,900 (0.3%) patients with a known or strong suspicion of MH susceptibility. For inpatients, the primary outcome occurred in 146,192 (25.1%) of the non-MH-susceptible group and in 337 (20.1%) of the MH-susceptible group (unadjusted risk difference [RD], -5.0%; 95% confidence interval [CI], -6.9 to -3.1%; P < 0.001). In outpatients, the primary outcome occurred in 9,146 (2.4%) of the non-MH-susceptible group and in 32 (2.6%) of the MH-susceptible group (RD, 0.2%; 95% CI, -0.7 to 1.1%; P = 0.72). After adjustment, MH susceptibility was not associated with the primary outcome in either the inpatients (adjusted risk difference [aRD], 1.2%; 95% CI, -1.3 to 3.6%; P = 0.35) or outpatients (aRD, -0.1%; 95% CI -1.0 to 0.9%; P = 0.90). CONCLUSIONS: Among adults in Ontario who underwent common surgeries under general anesthesia from 2009 to 2016, known or strongly suspected MH was not associated with a higher risk of adverse postoperative outcomes. These findings support the current standard of care management for MH-susceptible patients.

RéSUMé: OBJECTIF: Nous ignorons si les normes actuelles de gestion des soins de patients susceptibles d'hyperthermie maligne (HM) aboutissent à des résultats cliniques postopératoires acceptables à l'échelle d'une population. Notre objectif a été de déterminer si des patients présentant une susceptibilité à l'HM présentaient une évolution comparable à celle des patients non connus susceptibles après chirurgie sous anesthésie générale. MéTHODES: Il s'agissait d'une étude de cohorte rétrospective, basée sur une population de la province canadienne de l'Ontario allant du 1er avril 2009 au 31 mars 2016. Les participants étaient des adultes, hospitalisés ou ambulatoires, ayant subi des interventions sous anesthésie générale. L'exposition étudiée était une susceptibilité à l'HM connue ou fortement suspectée, déterminée par l'utilisation d'un code de facturation spécifique des médecins. Le critère d'évaluation principal était un critère composite incluant les décès toutes causes confondues, les réadmissions hospitalières ou les complications postopératoires majeures qui étaient survenus dans un délai de 30 jours postopératoires. Des analyses séparées ont été utilisées, selon que les patients avaient été hospitalisés ou opérés en chirurgie d'un jour. La probabilité inverse de la pondération de l'exposition basée sur le score pour la propension a servi à estimer les effets ajustés de l'exposition. RéSULTATS: La cohorte a inclus 957 876 patients (583 254 patients hospitalisés et 374 622 patients ambulatoires). Parmi eux, 2 900 patients (0,3 %) avaient une susceptibilité à l'HM connue ou fortement suspectée. Pour les patients hospitalisés, le critère d'évaluation principal est survenu chez 146 192 (25,1 %) des patients du groupe non susceptible d'HM et chez 337 (20,1 %) patients du groupe susceptible d'HM (différence de risques [DR] non ajustée : −5,0 %; intervalle de confiance [IC] à 95 % : −6,9 % à −3,1 %; P < 0,001). Pour les patients ambulatoires, le critère d'évaluation principal est survenu chez 9 146 (2,4 %) des patients du groupe non susceptible d'HM et chez 32 (2,6 %) patients du groupe susceptible d'HM (différence de risques [DR] non ajustée : 0,2 %; IC à 95 % : −0,7 % à 1,1 %; P = 0,72). Après ajustement, la susceptibilité à l'HM ne s'est pas avérée associée au critère d'évaluation principal dans le groupe de patients hospitalisés (différence de risques ajustée [DRa], 1,2 %; IC à 95 % : −1,3 % à 3,6 %; P = 0,35) ou dans le groupe de patients ambulatoires (DRa : −0,1 %; IC à 95 % : −1,0 % à 0,9 %; P = 0,90). CONCLUSIONS: Parmi les adultes de la province de l'Ontario ayant subi des interventions chirurgicales usuelles sous anesthésie générale entre 2009 et 2016, l'HM connue ou fortement suspectée n'a pas été associée à un plus grand risque d'évolution postopératoire défavorable. Ces constatations sont en faveur du maintien des normes des soins actuels pour la gestion des patients susceptibles d'HM.