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Learning technologies and globalization : pedagogical frameworks and applications
Describes the evolutionary and global impact of the techno-social transformation on learning technologies in terms of emerging pedagogical frameworks and applications, and provides examples of such applications in higher education, K-12, and the workplace, across the globe.
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Mammographic Density and the Risk and Detection of Breast Cancer
The light appearance of epithelium and stroma in a mammogram (mammographic density) can hide the presence of a cancer. A careful study of this problem found that extensive mammographic density is an important risk factor for breast cancer.
Mammographic density can hide the presence of a cancer. A careful study of this problem found that extensive mammographic density is an important risk factor for breast cancer.
The radiographic appearance of the breast varies among women because of differences in tissue composition and differences in the radiographic attenuation properties of fat, stroma, and epithelium.
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Fat is radiographically lucent and appears dark on a mammogram. In contrast, epithelium and stroma are radiographically dense and look light, an appearance we refer to as mammographic density. In 1976, Wolfe described an association between a qualitative classification of mammographic densities and the risk of breast cancer,
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,
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and now substantial literature shows that more extensive density is associated with an increased risk of breast cancer. Women with dense tissue in 75% . . .
Journal Article
Trends in the incidence and outcomes of heart failure in Ontario, Canada: 1997 to 2007
Heart failure is a leading cause of admission to hospital, but whether the incidence of heart failure is increasing or decreasing is uncertain. We examined temporal trends in the incidence and outcomes of heart failure in Ontario, Canada.
Using population-based administrative databases of hospital discharge abstracts and physician health insurance claims, we identified 419 551 incident cases of heart failure in Ontario between Apr. 1, 1997, and Mar. 31, 2008. All patients were classified as either inpatients or outpatients based on the patient's location at the time of the initial diagnosis. We tracked subsequent outcomes through linked administrative databases.
The age- and sex-standardized incidence of heart failure decreased 32.7% from 454.7 per 100 000 people in 1997 to 306.1 per 100 000 people in 2007 (p < 0.001). A comparable decrease in incidence occurred in both inpatient and outpatient settings. The greatest relative decrease occurred in patients aged 85 and over. Over the study period, 1-year risk-adjusted mortality decreased from 17.7% in 1997 to 16.2% in 2007 (p = 0.02) for outpatients, with a nonsignificant decrease from 35.7% in 1997 to 33.8% in 2007 (p = 0.1) for inpatients.
The incidence of heart failure decreased substantially during the study period. Nevertheless, the prognosis for patients with heart failure remains poor and is associated with high mortality.
Journal Article
Real‐world outcomes of FOLFIRINOX vs gemcitabine and nab‐paclitaxel in advanced pancreatic cancer: A population‐based propensity score‐weighted analysis
Background In Ontario, FOLFIRINOX (FFX) and gemcitabine + nab‐paclitaxel (GnP) have been publicly funded for first‐line unresectable locally advanced pancreatic cancer (uLAPC) or metastatic pancreatic cancer (mPC) since April 2015. We examined the real‐world effectiveness and safety of FFX vs GnP for advanced pancreatic cancer, and in uLAPC and mPC. Methods Patients receiving first‐line FFX or GnP from April 2015 to March 2017 were identified in the New Drug Funding Program database. Baseline characteristics and outcomes were obtained through the Ontario Cancer Registry and other population‐based databases. Overall survival (OS) was assessed using Kaplan‐Meier and weighted Cox proportional hazard models, weighted by the inverse propensity score adjusting for baseline characteristics. Weighted odds ratio (OR) for hospitalization and emergency department visits (EDV) were estimated from weighted logistic regression models. Results For 1130 patients (632 FFX, 498 GnP), crude median OS was 9.6 and 6.1 months for FFX and GnP, respectively. Weighted OS was improved for FFX vs GnP (HR = 0.77, 0.70‐0.85). Less frequent EDV and hospitalization were observed in FFX (EDV: 67.8%; Hospitalization: 49.2%) than GnP (EDV: 77.7%; Hospitalization: 59.3%). More frequent febrile neutropenia‐related hospitalization was observed in FFX (5.8%) than GnP (3.3%). Risk of EDV and hospitalization were significantly lower for FFX vs GnP (EDV: OR = 0.68, P = .0001; Hospitalization: OR = 0.76, P = .002), whereas the risk of febrile neutropenia‐related hospitalization was significantly higher (OR = 2.12, P = .001). Outcomes for uLAPC and mPC were similar. Conclusion In the real world, FFX had longer OS, less frequent all‐cause EDV and all‐cause hospitalization, but more febrile neutropenia‐related hospitalization compared to GnP. In the real world, implementation of universal public funding of FOLFIRINOX for metastatic pancreatic cancer was associated with improved overall survival, less frequent all‐cause emergency department visits, less frequent all‐cause hospitalization, but increased febrile neutropenia‐related hospitalization compared to patients treated with gemcitabine + nab‐paclitaxel. Expanding funding to include unresectable locally advanced pancreatic cancer was associated with a similar trend in benefits, but with improved absolute survival.
Journal Article
Diabetics can be identified in an electronic medical record using laboratory tests and prescriptions
With the increasing use of electronic medical records (EMRs) comes the potential to efficiently evaluate and improve quality of care. We set out to determine if diabetics could be accurately identified using structured data contained within an EMR.
We used a 5% random sample of adult patients (969 patients) within a convenience sample of 17 primary care physicians using Practices Solutions EMR in Ontario. A reference standard of diabetes status was manually confirmed by reviewing each patient's record. Accuracy for identifying people with diabetes was assessed using various combinations of laboratory tests and prescriptions. EMR data was also compared with administrative data.
A rule of one elevated blood sugar or a prescription for an antidiabetic medication had a 83.1% sensitivity, 98.2% specificity, 80.0% positive predictive value (PPV) and 98.5% negative predictive value (NPV) compared with the reference standard of diabetes status.
We found that the use of structured data within an EMR could be used to identify patients with diabetes. Our results have positive implications for policy makers, researchers, and clinicians as they develop registries of diabetic patients to examine quality of care using EMR data.
Journal Article
Benzene-associated immunosuppression and chronic inflammation in humans: a systematic review
ObjectiveRecent evidence has accumulated that the immune system is intimately intertwined with cancer development. Two key characteristics of carcinogens in which the immune system plays a central role are chronic inflammation and immunosuppression. In this systematic review, we investigated the association of chronic inflammatory and immunosuppressive outcomes with benzene, a widely used industrial chemical. Benzene has been confirmed to cause acute myeloid leukaemia and suspected to cause non-Hodgkin lymphoma, two cancers of the blood-forming system that affect immune cells.MethodsWe systematically searched PubMed and Embase for all relevant studies using a combination of Medical Subject Headings (MeSH) and selected key words. The detailed review protocol, including search strategy, was registered with PROSPERO, the international prospective register of systematic reviews (#CRD42019138611).ResultsBased on all human studies selected in the final review, we report new evidence of a benzene-induced immunosuppressive effect on the adaptive immune system and activation of the innate immune system to cause inflammation. In particular, benzene significantly lowers the number of white blood cells, particularly lymphocytes such as CD4+ T-cells, B-cells and natural killer cells, and increases proinflammatory biomarkers at low levels of exposure.ConclusionTo the best of our knowledge, this is the first comprehensive review of benzene’s immunotoxicity in humans. Based on results obtained from this review, we propose two potential immunotoxic mechanisms of how benzene induces leukaemia/lymphoma: (1) cancer invasion caused by proinflammatory cytokine production, and (2) cancer promotion via impaired immunosurveillance. Further studies will be required to confirm the connection between benzene exposure and its effects on the immune system.
Journal Article
Determinants of variations in coronary revascularization practices
The ratio of percutaneous coronary interventions to coronary artery bypass graft surgeries (PCI:CABG ratio) varies considerably across hospitals. We conducted a comprehensive study to identify clinical and nonclinical factors associated with variations in the ratio across 17 cardiac centres in the province of Ontario.
In this retrospective cohort study, we selected a population-based sample of 8972 patients who underwent an index cardiac catheterization between April 2006 and March 2007 at any of 17 hospitals that perform invasive cardiac procedures in the province. We classified the hospitals into four groups by PCI:CABG ratio (low [< 2.0], low–medium [2.0–2.7], medium–high [2.8–3.2] and high [> 3.2]). We explored the relative contribution of patient, physician and hospital factors to variations in the likelihood of patients receiving PCI or CABG surgery within 90 days after the index catheterization.
The mean PCI:CABG ratio was 2.7 overall. We observed a threefold variation in the ratios across the four hospital ratio groups, from a mean of 1.6 in the lowest ratio group to a mean of 4.6 in the highest ratio group. Patients with single-vessel disease usually received PCI (88.4%–99.0%) and those with left main artery disease usually underwent CABG (80.8%–94.2%), regardless of the hospital's procedure ratio. Variation in the management of patients with non-emergent multivessel disease accounted for most of the variation in the ratios across hospitals. The mode of revascularization largely reflected the recommendation of the physician performing the diagnostic catheterization and was also influenced by the revascularization “culture” at the treating hospital.
The physician performing the diagnostic catheterization and the treating hospital were strong independent predictors of the mode of revascularization. Opportunities exist to improve transparency and consistency around the decision-making process for coronary revascularization, most notably among patients with non-emergent multivessel disease.
Journal Article
Predictors of normal coronary arteries at coronary angiography
Coronary angiograms are important in the diagnostic workup of patients with suspected coronary artery disease. However, little is known about the clinical predictors of normal angiograms and whether this rate varies across different cardiac centers in Ontario.
We conducted a study using the Cardiac Care Network Variations in Revascularization Practice in Ontario database of 2,718 patients undergoing an index cardiac catheterization for an indication of stable angina between April 2006 and March 2007 at one of 17 cardiac hospitals in Ontario. We determined predictors of normal coronary angiograms (0% coronary stenosis) and compared rates of patients with normal catheterizations across centers.
Overall, 41.9% of patients with stable angina had a normal catheterization. A multivariate model demonstrated female gender to be the strongest predictor of a normal angiogram (odds ratio 3.55, 95% CI 2.93-4.28). In addition, atypical ischemic symptoms or no symptoms, the absence of diabetes, hyperlipidemia, smoking history, peripheral vascular disease, and angiography performed at a nonteaching site were associated with higher rates of normal catheterization. The rate of normal angiograms studied varied from 18.4% to 76.9% across hospitals and was more common in community compared with academic settings (47.1% vs 35.4%, P < .001).
The absence of traditional cardiac risk factors, female gender, and lack of typical angina symptoms are all associated with a higher frequency of normal cardiac catheterizations. The wide variation in Ontario in the frequency of normal angiograms in patients with stable angina suggests that there are opportunities to improve patient case selection.
Journal Article
Are population‐based patient‐reported outcomes associated with overall survival in patients with advanced pancreatic cancer?
Background Advanced pancreatic cancer (APC) patients often have substantial symptom burden. In Ontario, patients routinely complete the Edmonton Symptom Assessment Scale (ESAS), which screens for nine symptoms (scale: 0‐10), in cancer clinics. We explored the association between baseline patient‐reported outcomes, via ESAS, and overall survival (OS). Methods Advanced pancreatic cancer patients with ESAS records prior to receiving publicly funded drugs from November 2008 to March 2016 were retrospectively identified from Cancer Care Ontario's administrative databases. We examined three composite ESAS scores: total symptom distress score (TSDS: 9 symptoms), physical symptom score (PHS: 6/9 symptoms), and psychological symptom score (PSS: 2/9 symptoms); Composite scores greater than defined thresholds (TSDS ≥36, PHS ≥24, PSS ≥8) were considered as high symptom burden. Crude OS was assessed using Kaplan‐Meier method. Hazard ratios (HRs) were assessed using multivariable Cox models. Analysis was repeated in a sub‐cohort with Eastern Cooperative Oncology Group (ECOG) status and metastasis. Results We identified 2199 APC patients (mean age 64 years, 55% male) with ESAS records prior to receiving chemotherapy. Crude median survival was 4.5 and 7.3 months for high and low TSDS, respectively. High TSDS was associated with lower OS (HR = 1.47, 95% CI: 1.33, 1.63). In the sub‐cohort (n = 393) with ECOG status and metastasis, high TSDS was also associated with lower OS (HR = 1.34, 95% CI: 1.04, 1.73). Similar trends were observed for PHS and PSS. Conclusions Higher burden of patient‐reported outcome was associated with reduced OS among APC patients. The effect was prominent after adjusting for ECOG status. In a cohort of advanced pancreatic cancer patients, we observed that higher burden of patient‐reported symptoms at baseline is associated with reduced overall survival. The association remained significant after accounting for performance status and type of treatment.
Journal Article
The effectiveness of rituximab and HIV on the survival of Ontario patients with diffuse large B‐cell lymphoma
Introduction For patients with diffuse large B‐cell lymphoma (DLBCL), standard‐care is rituximab administered with CHOP or CHOP‐like chemotherapy (R‐CHOP). However, the effectiveness and safety of R‐CHOP among DLBCL patients with human immunodeficiency virus (HIV) infection is less clear, as HIV+ patients were omitted from most clinical trials and population‐level data from unselected patients are limited. R‐CHOP was funded for HIV‐associated DLBCL patients with CD4 >50/mm3 in Ontario in February 2015. Methods Patients with a new diagnosis of DLBCL were identified from the Ontario Cancer Registry between April 2010 and March 2018. HIV diagnosis and chemotherapy regimen were ascertained using administrative databases at Ontario Health. The effect of rituximab and HIV on overall survival was assessed in the HIV+ subgroup (R‐CHOP vs CHOP) and in the R‐CHOP subgroup (HIV+ vs HIV−). Results Among HIV+ patients, receipt of R‐CHOP was associated with a fivefold improvement in overall survival (hazard ratio [HR] 0.29 (0.13‐0.66) compared with CHOP), after adjustment. Among patients who received R‐CHOP (n = 6106), older age, male sex, lower neighborhood income, and higher comorbidity were associated with worse overall survival, after adjustment (P < .001 for all), but HIV positivity was not prognostic (HR 1.12 (0.60‐2.10)). Within 1‐year after diagnosis, HIV+ patients receiving R‐CHOP had a similar proportion of patients who visited the emergency department (67% vs 66% P = .43) or admitted to hospital (58% vs 52%, P = .43) and as HIV− patients receiving R‐CHOP. Conclusion HIV status did not affect prognosis for patients with DLBCL receiving R‐CHOP in an unselected general population when rituximab was used according to funding criteria. R‐CHOP was safe and effective for DLBCL treatment, regardless of HIV status. The standard of care for patients with aggressive‐histology B‐cell lymphoma is rituximab in addition to a CHOP or CHOP‐like chemotherapy regimen. For HIV+ patients, there are less data available on the effectiveness of this treatment, but in 2015, policy changes in Ontario extended this treatment modality to this subgroup of patients. In the present study, we demonstrate that rituximab with CHOP is as safe and effective for HIV+ patients as it is for HIV− patients.
Journal Article