Health Administrative Databases In Ontario Research Articles

Association between quality domains and health care spending across physician networks.

One of the more fundamental health policy questions is the relationship between health care quality and spending. A better understanding of these relationships is needed to inform health systems interventions aimed at increasing quality and efficiency of care. We measured 65 validated quality indicators (QI) across Ontario physician networks. QIs were aggregated into domains representing six dimensions of care: screening and prevention, evidence-based medications, hospital-community transitions (7-day post-discharge visit with a primary care physician; 30-day post-discharge visit with a primary care physician and specialist), potentially avoidable hospitalizations and emergency department (ED) visits, potentially avoidable readmissions and unplanned returns to the ED, and poor cancer end of life care. Each domain rate was computed as a weighted average of QI rates, weighting by network population at risk. We also measured overall and sector-specific per capita healthcare network spending. We evaluated the associations between domain rates, and between domain rates and spending using weighted correlations, weighting by network population at risk, using an ecological design. All indicators were measured using Ontario health administrative databases. Large variations were seen in timely hospital-community transitions and potentially avoidable hospitalizations. Networks with timely hospital-community transitions had lower rates of avoidable admissions and readmissions (r = -0.89, -0.58, respectively). Higher physician spending, especially outpatient primary care spending, was associated with lower rates of avoidable hospitalizations (r = -0.83) and higher rates of timely hospital-community transitions (r = 0.81) and moderately associated with lower readmission rates (r = -0.46). Investment in effective primary care services may help reduce burden on the acute care sector and associated expenditures.

Mortality risk associated with psychological distress and major depression: A population-based cohort study

BackgroundFew studies have examined the impact of psychological distress on mortality. We aimed to estimate mortality rates of psychological distress and major depressive disorder (MDD) compared to a referent group with no MDD or psychological distress. MethodsOur study population (N = 10 181) consisted of respondents from the Canadian Community Health Survey Cycle 1.2 linked to Ontario health administrative databases followed for up to 11 years. We used Cox proportional hazards models to assess overall, sex-specific, as well as short-term (within two years of follow-up) and long-term (follow-up ≥ two years) mortality among those with DSM-criteria MDD and psychological distress independent of MDD adjusted for socio-demographic, lifestyle and clinical factors. ResultsIndividuals with psychological distress (n = 666) had a similar mortality rate as those with MDD (n = 428) and significantly greater adjusted hazards of death than the referent group (hazard ratio = 1.57, 95% CI = 1.14–2.15). The risk of death was greatest in the short-term among those with MDD, however, we observed a persistent 1.6-fold increased risk in both the short- and long-term among those with psychological distress compared to the referent. Women with MDD had the greatest mortality rate and died a median of 15 years earlier than women in the referent group. LimitationsPsychological distress and MDD were ascertained at baseline with small number of deaths in the early follow-up period. Survey variables were prone to self-report bias with a possibility of residual confounding. ConclusionsFocused longitudinal research and targeted management strategies for those with psychological distress and women with MDD are warranted.

Thiazide Diuretic Dose and Risk of Kidney Stones in Older Adults: A Retrospective Cohort Study.

Background:Thiazide diuretics are commonly prescribed to prevent kidney stones. However, it is unclear whether higher doses confer greater benefit.Objective:To determine whether lower doses of thiazide diuretics confer a similar protective effect against kidney stone events as higher doses.Design:Population-based cohort study.Setting:Linked health administrative databases in Ontario, Canada.Patients:Older adults newly prescribed a thiazide diuretic between 2003 and 2014 were separated into 2 groups based on daily dose: low dose (⩽12.5 mg hydrochlorothiazide/chlorthalidone, or ⩽1.25 mg indapamide) or high dose.Measurements:The primary outcome was time to a kidney stone event, using diagnosis and procedure codes. A secondary outcome was kidney stone surgery.Methods:An association between thiazide diuretic dose and a kidney stone event was estimated using Cox proportional hazards regression.Results:A total of 536 of 105 239 patients (0.51%) experienced a kidney stone event. We did not detect a difference in kidney stone risk in the high-dose relative to the low-dose group (adjusted hazard ratio, 1.10; 95% confidence interval, 0.93-1.31). Results were similar when analysis was restricted to the more specific outcome of kidney stone surgery. Neither a history of prior kidney stones nor the type of thiazide diuretic modified the effect of diuretic dose on outcome.Limitations:Patients were >65 years old and we were unable to adjust for some potential confounders such as dietary factors.Conclusions:Lower dose thiazide diuretics appear to confer a similar protective effect as higher dose thiazides against the development of kidney stones.

Is there seasonality in hospitalizations for major depressive disorder in Canada?

Abstract Background Canada, a temperate country with four defined seasons incurs an annual productivity loss of over $30 billion on major depressive disorder (MDD); however it remains unknown whether inpatient hospitalization for MDD exhibits seasonal variations. Objective Our study objective was to determine if there are seasonal variations in hospitalization rates for MDD in Canada. Methods We used time series analysis to determine monthly rates of hospitalizations for MDD from 2006 – 2013, on data from population level health-administrative databases in Ontario, Canada. We also stratified analysis by gender and three age groups: 18 to 39, 40 to 65 and those over 65. We compared demographic and comorbidity profiles of patients admitted in April, August and December to elucidate if patient characteristics differed by season of admission. Results We identified a total of 130,336 admissions for MDD for 95,439 unique patients. Baseline characteristics of the patients were similar across seasons. We did not detect significant seasonality of hospitalizations for MDD across any of the gender or age subgroups. Discussion Our results question the popularly held belief that hospitalizations for MDD vary with seasons. These findings highlight the need for uniform hospital resource allocation for MDD throughout the year in Canada.

The risk of mycobacterial infections associated with inhaled corticosteroid use.

Inhaled corticosteroid (ICS) use is associated with an increased risk of pneumonia. This study was performed to determine if ICS use is associated with an increased risk of nontuberculous mycobacterial pulmonary disease (NTM-PD) or tuberculosis (TB).We conducted a population-based nested case-control study using linked laboratory and health administrative databases in Ontario, Canada, including adults aged ≥66 years with treated obstructive lung disease (i.e. asthma, chronic obstructive pulmonary disease (COPD) or asthma-COPD overlap syndrome) between 2001 and 2013. We estimated odds ratios comparing ICS use with nonuse among NTM-PD and TB cases and controls using conditional logistic regression.Among 417 494 older adults with treated obstructive lung disease, we identified 2966 cases of NTM-PD and 327 cases of TB. Current ICS use was associated with NTM-PD compared with nonuse (adjusted OR (aOR) 1.86, 95% CI 1.60-2.15) and was statistically significant for fluticasone (aOR 2.09, 95% CI 1.80-2.43), but not for budesonide (aOR 1.19, 95% CI 0.97-1.45). There was a strong dose-response relationship between incident NTM-PD and cumulative ICS dose over 1 year. There was no significant association between current ICS use and TB (aOR 1.43, 95% CI 0.95-2.16).This study suggests that ICS use is associated with an increased risk of NTM-PD, but not TB.

Outcomes associated with a pediatric clinical diabetes network in Ontario: a population-based time-trend analysis.

The Network of Ontario Pediatric Diabetes Programs was implemented in 2001. The objective of this study was to determine whether implementation of the network was associated with a decrease in the risk of acute diabetes-related complications and a reduction in the socioeconomic and geographic disparities in these outcomes. We conducted a population-based time trend analysis of children (< 18 yr) with diabetes using health administrative databases in Ontario from 1996 to 2011. We determined the relation between network implementation and diabetes-related emergency department visits and hospital admissions using linear mixed-effects models with a Poisson link function. Data for 13 806 children with established diabetes were analyzed. After the network was implemented, there was a significant decrease in the rate per 100 children of emergency department visits (17.0 in 2001 v. 10.00 in 2011, p < 0.001) and hospital admissions (8.8 v. 5.0, p < 0.001). The decrease was most significant for those in the lowest socioeconomic quintile and in urban areas. After network implementation, children in the lowest socioeconomic quintile remained at higher risk than those in the highest socioeconomic quintile for emergency department visits (adjusted rate ratio [RRafter] 1.77 [95% confidence interval (CI) 1.55 to 2.03]) and hospital admissions (RRafter 2.11 [95% CI 1.77 to 2.52]). However, the yearly decrease in rates of emergency department visits and hospital admissions for the lowest compared to the highest socioeconomic quintile shifted toward a decreasing disparity after network implementation (p < 0.05). Before the network was implemented, geographic location was not associated with outcomes. After implementation, the risk of emergency department visits among patients from urban areas was significantly lower than that among patients from rural areas. The establishment of a pediatric diabetes network was associated with better health outcomes, particularly for patients of lower socioeconomic status. Further work is needed to address the health care needs of those in rural areas.

Association of the Timing of Pregnancy With Survival in Women With Breast Cancer

ImportanceIncreasing numbers of women experience pregnancy around the time of, or after, a diagnosis of breast cancer. Understanding the effect of pregnancy on survival in women with breast cancer will help in the counseling and treatment of these women.ObjectiveTo compare the overall survival of women diagnosed with breast cancer during pregnancy or in the postpartum period with that of women who had breast cancer but did not become pregnant.Design, Setting, and ParticipantsThis population-based, retrospective cohort study linked health administrative databases in Ontario, Canada, comprising 7553 women aged 20 to 45 years at the time of diagnosis with invasive breast cancer, from January 1, 2003, to December 31, 2014.ExposuresAny pregnancy in the period from 5 years before, until 5 years after, the index date of the diagnosis of breast cancer. Women were classified into the following 4 exposure groups: no pregnancy (the referent), pregnancy before breast cancer, pregnancy-associated breast cancer, and pregnancy following breast cancer.Main Outcomes and MeasuresFive-year actuarial survival rates for all exposure groups, age-adjusted and multivariable hazard ratios [HRs] of pregnancy for overall survival for all exposure groups, and time-dependent hazard ratios for women with pregnancy following breast cancer.ResultsAmong the 7553 women in the study (mean age at diagnosis, 39.1 years; median, 40 years; range, 20-44 years) the 5-year actuarial survival rate was 87.5% (95% CI, 86.5%-88.4%) for women with no pregnancy, 85.3% (95% CI, 82.8%-87.8%) for women with pregnancy before breast cancer (age-adjusted hazard ratio, 1.03; 95% CI, 0.85-1.27; P = .73), and 82.1% (95% CI, 78.3%-85.9%) for women with pregnancy-associated breast cancer (age-adjusted hazard ratio, 1.18; 95% CI, 0.91-1.53; P = .20). The 5-year actuarial survival rate was 96.7% (95% CI, 94.1%-99.3%) for women who had pregnancy 6 months or more after diagnosis of breast cancer, vs 87.5% (95% CI, 86.5%-88.4%) for women with no pregnancy) (age-adjusted HR, 0.22; 95% CI, 0.10-0.49; P < .001).Conclusions and RelevancePregnancy did not adversely affect survival in women with breast cancer. For breast cancer survivors who wish to conceive, the risk of death is lowest if pregnancy occurs 6 months or more after diagnosis.

Is there seasonality in hospitalizations for Major Depressive Disorder in Canada?

Abstract Background Canada, a temperate country with four defined seasons incurs an annual productivity loss of over $30 billion on major depressive disorder (MDD); however it remains unknown whether inpatient hospitalization for MDD exhibits seasonal variations. Objective Our study objective was to determine if there are seasonal variations in hospitalization rates for MDD in Canada. Methods We used time series analysis to determine monthly rates of hospitalizations for MDD from 2006 – 2013, on data from population level health-administrative databases in Ontario, Canada. We also stratified analysis by gender and three age groups: 18 to 39, 40 to 65 and those over 65. We compared demographic and comorbidity profiles of patients admitted in April, August and December to elucidate if patient characteristics differed by season of admission. Results We identified a total of 130,336 admissions for MDD for 95,439 unique patients. Baseline characteristics of the patients were similar across seasons. We did not detect significant seasonality of hospitalizations for MDD across any of the gender or age subgroups. Discussion Our results question the popularly held belief that hospitalizations for MDD vary with seasons. These findings highlight the need for uniform hospital resource allocation for MDD throughout the year in Canada.

Validation of Carotid Artery Revascularization Coding in Ontario Health Administrative Databases.

The positive predictive value (PPV) of carotid endarterectomy (CEA) and carotid artery stenting (CAS) procedure and post-operative complication coding were assessed in Ontario health administrative databases. Between 1 April 2002 and 31 March 2014, a random sample of 428 patients were identified using Canadian Classification of Health Intervention (CCI) procedure codes and Ontario Health Insurance Plan (OHIP) billing codes from administrative data. A blinded chart review was conducted at two high-volume vascular centers to assess the level of agreement between the administrative records and the corresponding patients' hospital charts. PPV was calculated with 95% confidence intervals (CIs) to estimate the validity of CEA and CAS coding, utilizing hospital charts as the gold standard. Sensitivity of CEA and CAS coding were also assessed by linking two independent databases of 540 CEA-treated patients (Ontario Stroke Registry) and 140 CAS-treated patients (single-center CAS database) to administrative records. PPV for CEA ranged from 99% to 100% and sensitivity ranged from 81.5% to 89.6% using CCI and OHIP codes. A CCI code with a PPV of 87% (95% CI, 78.8-92.9) and sensitivity of 92.9% (95% CI, 87.4-96.1) in identifying CAS was also identified. PPV for post-admission complication diagnosis coding was 71.4% (95% CI, 53.7-85.4) for stroke/transient ischemic attack, and 82.4% (95% CI, 56.6-96.2) for myocardial infarction. Our analysis demonstrated that the codes used in administrative databases accurately identify CEA and CAS-treated patients. Researchers can confidently use administrative data to conduct population-based studies of CEA and CAS.

The influence of cholinesterase inhibitor therapy for dementia on risk of cardiac pacemaker insertion: a retrospective, population-based, health administrative databases study in Ontario, Canada.

BackgroundCholinesterase inhibitors are used to treat the symptoms of dementia and can theoretically cause bradycardia. Previous studies suggest that patients taking these medications have an increased risk of undergoing pacemaker insertion. Since these drugs have a marginal impact on patient outcomes, it might be preferable to change drug treatment rather than implant a pacemaker. This population-based study determined the association of people with dementia exposed to cholinesterase inhibitor medication and pacemaker insertion.MethodsWe used data from the Ontario health administrative databases from January 1, 1993 to June 30, 2012. We included all community-dwelling seniors who had a code for dementia and were exposed to cholinesterase inhibitors (donezepil, galantamine, and rivastigmine) and/or drugs used to treat co-morbidities of hypertension, diabetes, depression and hypothyroidism. We controlled for exposure to anti-arrhythmic drugs. Observation started at first exposure to any medication and continued until the earliest of pacemaker insertion, death, or end of study.Results2,353,909 people were included with 96,000 (4.1%) undergoing pacemaker insertion during the observation period. Case–control analysis showed that pacemaker patients were less likely to be coded with dementia (unadjusted OR 0.42 [95%CI 0.41-0.42]) or exposed to cholinesterase inhibitors (unadjusted OR 0.39 [95%CI 0.37-0.41]). That Cohort analysis showed patients with dementia taking cholinesterase inhibitors had a decreased risk of pacemaker insertion (unadj-HR 0.58 [0.55-0.61]). Adjustment for patient age, sex, and other medications did not notably change results, as did restricting the analysis to incident users.ConclusionsPatients taking cholinesterase inhibitors rarely undergo, and have a significantly reduced risk of, cardiac pacemaker insertion.

Clinician Perspectives on Preparing for and Conducting Family Meetings (S773)

T13 and T18 over a 20-year period; 2) To evaluate the association between interventions and survival. Methods. Using linked Ontario health administrative databases that capture all hospitalizations in the single-payer healthcare system, we created a retrospective cohort of children born between April 1, 1991 and March 31, 2012 with a diagnosis code for T13 or T18 on a discharge record. Demographic data and procedure codes were extracted from hospitalization discharges through March 31, 2013. Survival times were calculated from listed birth and death dates; patients without death dates were censored at the most recent hospital discharge date. Results. The trisomy 13 cohort included 195 individuals; 161 (82.6%) died during follow-up. Of the 268 children with trisomy 18, 232 (86.6%) died. Median ages at death were 7 days and 5.5 days, respectively; the oldest children in the cohorts were 17 years in trisomy 13 and 15 years in trisomy 18. 80 children with trisomy 13 and 100 children with trisomy 18 received a total of 2141 procedures. Interventions per year increased over time from 10 in 1991 to 58 in 2012. Details about specific procedure types and association with survival will be forthcoming. Conclusions. Children with T13 and T18 in Ontario are receiving increasing numbers of interventions over time. Implications. Interventional outcomes will help guide family and clinician decision-making for care of children with T13 and T18.

Obstructive sleep apnea and the prevalence and incidence of cancer.

A link between obstructive sleep apnea and cancer development or progression has been suggested, possibly through chronic hypoxemia, but supporting evidence is limited. We examined the association between the severity of obstructive sleep apnea and prevalent and incident cancer, controlling for known risk factors for cancer development. We included all adults referred with possible obstructive sleep apnea who underwent a first diagnostic sleep study at a single large academic hospital between 1994 and 2010. We linked patient data with data from Ontario health administrative databases from 1991 to 2013. Cancer diagnosis was derived from the Ontario Cancer Registry. We assessed the cross-sectional association between obstructive sleep apnea and prevalent cancer at the time of the sleep study (baseline) using logistic regression analysis. Cox regression models were used to investigate the association between obstructive sleep apnea and incident cancer among patients free of cancer at baseline. Of 10 149 patients who underwent a sleep study, 520 (5.1%) had a cancer diagnosis at baseline. Over a median follow-up of 7.8 years, 627 (6.5%) of the 9629 patients who were free of cancer at baseline had incident cancer. In multivariable regression models, the severity of sleep apnea was not significantly associated with either prevalent or incident cancer after adjustment for age, sex, body mass index and smoking status at baseline (apnea-hypopnea index > 30 v. < 5: adjusted odds ratio [OR] 0.96, 95% confidence interval [CI] 0.71-1.30, for prevalent cancer, and adjusted hazard ratio [HR] 1.02, 95% CI 0.80-1.31, for incident cancer; sleep time spent with oxygen saturation < 90%, per 10-minute increase: adjusted OR 1.01, 95% CI 1.00-1.03, for prevalent cancer, and adjusted HR 1.00, 95% CI 0.99-1.02, for incident cancer). In a large cohort, the severity of obstructive sleep apnea was not independently associated with either prevalent or incident cancer. Additional studies are needed to elucidate whether there is an independent association with specific types of cancer.

Cost-effectiveness of first-line treatments for patients with KRAS wild-type metastatic colorectal cancer.

Combinations of chemotherapy regimens and monoclonal antibodies have been demonstrated to improve clinical outcomes in patients with metastatic colorectal cancer (mcrc). Although these combination treatment strategies are safe and effective in first-line treatment for mcrc, little is known about their economic consequences and resource allocation implications. In the present study, we evaluated the cost-effectiveness of bevacizumab plus folfiri, cetuximab plus folfiri, and panitumumab plus folfiri for patients with KRAS wild-type mcrc. A Markov model simulated the lifetime patient outcomes and costs of each first-line treatment strategy and subsequent lines of treatment from the perspective of the health care payer in Ontario. The model was parameterized using data from the Ontario Cancer Registry, Ontario health administrative databases, and published randomized control trials. Patient outcomes were measured in quality-adjusted life years (qalys), and costs were measured in monetary terms. Costs and outcomes were both discounted at 5% and expressed in 2012 Canadian dollars. For mcrc patients with KRAS wild-type disease, the treatment strategy of bevacizumab plus folfiri was found to dominate the other two first-line treatment strategies. Sensitivity analyses revealed that the incremental cost-effectiveness ratio values were sensitive to the effectiveness of treatment, the costs of bevacizumab and cetuximab, and health utility values. Evidence from Ontario showed that bevacizumab plus folfiri is the cost-effective first-line treatment strategy for patients with KRAS wild-type mcrc. The panitumumab plus folfiri and cetuximab plus folfiri options were both dominated, but the cetuximab plus folfiri strategy must be further investigated given that, in the sensitivity analyses, the cost-effectiveness of that strategy was found to be superior to that of bevacizumab plus folfiri under certain ranges of parameter values.

Estimating Influenza Vaccine Effectiveness in Community-Dwelling Elderly Patients Using the Instrumental Variable Analysis Method

Estimates of influenza vaccine effectiveness in elderly individuals are largely from observational studies, which are susceptible to bias. Instrumental variable (IV) methods control for overt and hidden biases in observational studies. We used linked health administrative databases in Ontario to examine the association between influenza vaccination and all-cause mortality among community-dwelling individuals older than 65 years for 9 influenza seasons (2000-2001 to 2008-2009). We examined the composite of hospitalization for pneumonia and influenza and all-cause mortality as a secondary outcome. We used logistic regression modeling and IV analysis to remove the effect of selection bias. We included 12621806 person-influenza seasons of observation. Logistic regression produced adjusted odds ratios of 0.67 (95% CI, 0.62-0.72) for all-cause mortality during influenza seasons and 0.85 (0.83-0.86) during post-influenza seasons when influenza is not circulating, suggesting the presence of bias. In contrast, IV analysis yielded adjusted odds ratios of 0.94 (95% CI, 0.84-1.03) during influenza seasons and 1.13 (1.07-1.19) during post-influenza seasons. For the composite of hospitalization for pneumonia and influenza and death, logistic regression produced adjusted odds ratios of 0.74 (95% CI, 0.70-0.78) during influenza seasons and 0.88 (0.87-0.90) during post-influenza seasons, whereas IV analysis produced adjusted odds ratios of 0.86 (95% CI, 0.79-0.92) and 1.02 (0.97-1.06), respectively. Influenza vaccination is associated with reductions in the composite of hospitalizations for pneumonia and influenza and all-cause mortality during the influenza season but not mortality alone. Compared with standard modeling, IV analysis appears to produce less-biased estimates of vaccine effectiveness.

Low income children with Inflammatory Bowel Disease have higher surgical and hospitalization rates in a Universal Health Care System

Canada's single-payer health system provides all residents of Ontario, Canada's largest province, with publicly-funded healthcare. Nonetheless, previous studies have demonstrated income-based disparities in health services utilization and outcomes in children with chronic diseases. To test whether there are important differences in healthcare utilization and outcomes based on household income in children with IBD. The Ontario Crohn's and Colitis Cohort uses a validated algorithm to identify all children <18 years diagnosed 1994-2004 with IBD within Ontario's health administrative databases. Children were followed until 2008. Patients were grouped into census-based mean neighborhood income quintiles groupings: the lowest two income quintiles (n= 944) and highest two income quintiles (n= 1286). Multivariable models tested the association between income group and physician and emergency department (ED) visits, hospitalizations, or surgery. Logistic, linear or Cox proportional hazard regression models were used. Covariates were determined a priori (sex, diagnosis age) or included if they changed the estimate of the income group variable by ≥10% (incidence date, rurality at birth and at diagnosis). 2230 IBD patients were included (age at diagnosis 14.4±3.9y, follow-up 8.4±3.2y [range 3-14y]). Care providers (adult/pediatric gastroenterologists, surgeons) were similar between groups. Lower income children were more likely to be hospitalized or visit the ED and had more physician IBD-related visits (see Table). Lower income children with Crohn's (not UC) were more likely to undergo surgery within 3y of diagnosis. IBD-RELATED HEALTH SERVICES UTILIZATION BY NEIGHBORHOOD INCOME QUINTILE GROUP. IBD-RELATED HEALTH SERVICES UTILIZATION BY NEIGHBORHOOD INCOME QUINTILE GROUP. In the context of higher overall physician visits in low income children with IBD, higher surgical rates in those with Crohn's disease, and higher hospitalization rates in all children with IBD are likely due to factors other than access to healthcare services. Further work should delineate whether there are potentially modifiable risk factors associated with these worse health outcomes in children of lower income families.